/*
- * This file implements the perfmon subsystem which is used
+ * This file implements the perfmon-2 subsystem which is used
* to program the IA-64 Performance Monitoring Unit (PMU).
*
- * Originally Written by Ganesh Venkitachalam, IBM Corp.
- * Copyright (C) 1999 Ganesh Venkitachalam <venkitac@us.ibm.com>
+ * The initial version of perfmon.c was written by
+ * Ganesh Venkitachalam, IBM Corp.
*
- * Modifications by Stephane Eranian, Hewlett-Packard Co.
- * Modifications by David Mosberger-Tang, Hewlett-Packard Co.
+ * Then it was modified for perfmon-1.x by Stephane Eranian and
+ * David Mosberger, Hewlett Packard Co.
+ *
+ * Version Perfmon-2.x is a rewrite of perfmon-1.x
+ * by Stephane Eranian, Hewlett Packard Co.
*
* Copyright (C) 1999-2003 Hewlett Packard Co
* Stephane Eranian <eranian@hpl.hp.com>
* David Mosberger-Tang <davidm@hpl.hp.com>
+ *
+ * More information about perfmon available at:
+ * http://www.hpl.hp.com/research/linux/perfmon
*/
#include <linux/config.h>
#include <linux/vmalloc.h>
#include <linux/mm.h>
#include <linux/sysctl.h>
-#include <linux/smp.h>
+#include <linux/list.h>
+#include <linux/file.h>
+#include <linux/poll.h>
+#include <linux/vfs.h>
+#include <linux/pagemap.h>
+#include <linux/mount.h>
+#include <linux/version.h>
#include <asm/bitops.h>
#include <asm/errno.h>
#include <asm/signal.h>
#include <asm/system.h>
#include <asm/uaccess.h>
-#include <asm/delay.h> /* for ia64_get_itc() */
+#include <asm/delay.h>
#ifdef CONFIG_PERFMON
-
/*
- * For PMUs which rely on the debug registers for some features, you must
- * you must enable the following flag to activate the support for
- * accessing the registers via the perfmonctl() interface.
+ * perfmon context state
*/
-#if defined(CONFIG_ITANIUM) || defined(CONFIG_MCKINLEY)
-#define PFM_PMU_USES_DBR 1
-#endif
+#define PFM_CTX_UNLOADED 1 /* context is not loaded onto any task */
+#define PFM_CTX_LOADED 2 /* context is loaded onto a task */
+#define PFM_CTX_MASKED 3 /* context is loaded but monitoring is masked due to overflow */
+#define PFM_CTX_ZOMBIE 4 /* owner of the context is closing it */
+#define PFM_CTX_TERMINATED 5 /* the task the context was loaded onto is gone */
-/*
- * perfmon context states
- */
-#define PFM_CTX_DISABLED 0
-#define PFM_CTX_ENABLED 1
+#define CTX_LOADED(c) (c)->ctx_state = PFM_CTX_LOADED
+#define CTX_UNLOADED(c) (c)->ctx_state = PFM_CTX_UNLOADED
+#define CTX_ZOMBIE(c) (c)->ctx_state = PFM_CTX_ZOMBIE
+#define CTX_DESTROYED(c) (c)->ctx_state = PFM_CTX_DESTROYED
+#define CTX_MASKED(c) (c)->ctx_state = PFM_CTX_MASKED
+#define CTX_TERMINATED(c) (c)->ctx_state = PFM_CTX_TERMINATED
+
+#define CTX_IS_UNLOADED(c) ((c)->ctx_state == PFM_CTX_UNLOADED)
+#define CTX_IS_LOADED(c) ((c)->ctx_state == PFM_CTX_LOADED)
+#define CTX_IS_ZOMBIE(c) ((c)->ctx_state == PFM_CTX_ZOMBIE)
+#define CTX_IS_MASKED(c) ((c)->ctx_state == PFM_CTX_MASKED)
+#define CTX_IS_TERMINATED(c) ((c)->ctx_state == PFM_CTX_TERMINATED)
+#define CTX_IS_DEAD(c) ((c)->ctx_state == PFM_CTX_TERMINATED || (c)->ctx_state == PFM_CTX_ZOMBIE)
+
+#define PFM_INVALID_ACTIVATION (~0UL)
-/*
- * Reset register flags
- */
-#define PFM_PMD_LONG_RESET 1
-#define PFM_PMD_SHORT_RESET 2
/*
- * Misc macros and definitions
+ * depth of message queue
*/
-#define PMU_FIRST_COUNTER 4
-#define PMU_MAX_PMCS 256
-#define PMU_MAX_PMDS 256
+#define PFM_MAX_MSGS 32
+#define PFM_CTXQ_EMPTY(g) ((g)->ctx_msgq_head == (g)->ctx_msgq_tail)
/*
* type of a PMU register (bitmask).
* bitmask structure:
* bit0 : register implemented
- * bit1 : end marker
+ * bit1 : end marker
* bit2-3 : reserved
- * bit4-7 : register type
+ * bit4 : pmc has pmc.pm
+ * bit5 : pmc controls a counter (has pmc.oi), pmd is used as counter
+ * bit6-7 : register type
* bit8-31: reserved
*/
+#define PFM_REG_NOTIMPL 0x0 /* not implemented at all */
#define PFM_REG_IMPL 0x1 /* register implemented */
#define PFM_REG_END 0x2 /* end marker */
#define PFM_REG_MONITOR (0x1<<4|PFM_REG_IMPL) /* a PMC with a pmc.pm field only */
-#define PFM_REG_COUNTING (0x2<<4|PFM_REG_IMPL) /* a PMC with a pmc.pm AND pmc.oi, a PMD used as a counter */
-#define PFM_REG_CONTROL (0x3<<4|PFM_REG_IMPL) /* PMU control register */
-#define PFM_REG_CONFIG (0x4<<4|PFM_REG_IMPL) /* refine configuration */
-#define PFM_REG_BUFFER (0x5<<4|PFM_REG_IMPL) /* PMD used as buffer */
+#define PFM_REG_COUNTING (0x2<<4|PFM_REG_MONITOR|PFM_REG_IMPL) /* a monitor + pmc.oi+ PMD used as a counter */
+#define PFM_REG_CONTROL (0x4<<4|PFM_REG_IMPL) /* PMU control register */
+#define PFM_REG_CONFIG (0x8<<4|PFM_REG_IMPL) /* configuration register */
+#define PFM_REG_BUFFER (0xc<<4|PFM_REG_IMPL) /* PMD used as buffer */
#define PMC_IS_LAST(i) (pmu_conf.pmc_desc[i].type & PFM_REG_END)
#define PMD_IS_LAST(i) (pmu_conf.pmd_desc[i].type & PFM_REG_END)
-#define PFM_IS_DISABLED() pmu_conf.disabled
+#define PFM_IS_DISABLED() (pmu_conf.enabled == 0)
-#define PMC_OVFL_NOTIFY(ctx, i) ((ctx)->ctx_soft_pmds[i].flags & PFM_REGFL_OVFL_NOTIFY)
-#define PFM_FL_INHERIT_MASK (PFM_FL_INHERIT_NONE|PFM_FL_INHERIT_ONCE|PFM_FL_INHERIT_ALL)
+#define PMC_OVFL_NOTIFY(ctx, i) ((ctx)->ctx_pmds[i].flags & PFM_REGFL_OVFL_NOTIFY)
-/* i assume unsigned */
+/* i assumed unsigned */
#define PMC_IS_IMPL(i) (i< PMU_MAX_PMCS && (pmu_conf.pmc_desc[i].type & PFM_REG_IMPL))
#define PMD_IS_IMPL(i) (i< PMU_MAX_PMDS && (pmu_conf.pmd_desc[i].type & PFM_REG_IMPL))
-/* XXX: these three assume that register i is implemented */
-#define PMD_IS_COUNTING(i) (pmu_conf.pmd_desc[i].type == PFM_REG_COUNTING)
-#define PMC_IS_COUNTING(i) (pmu_conf.pmc_desc[i].type == PFM_REG_COUNTING)
-#define PMC_IS_MONITOR(i) (pmu_conf.pmc_desc[i].type == PFM_REG_MONITOR)
+/* XXX: these assume that register i is implemented */
+#define PMD_IS_COUNTING(i) ((pmu_conf.pmd_desc[i].type & PFM_REG_COUNTING) == PFM_REG_COUNTING)
+#define PMC_IS_COUNTING(i) ((pmu_conf.pmc_desc[i].type & PFM_REG_COUNTING) == PFM_REG_COUNTING)
+#define PMC_IS_MONITOR(i) ((pmu_conf.pmc_desc[i].type & PFM_REG_MONITOR) == PFM_REG_MONITOR)
#define PMC_DFL_VAL(i) pmu_conf.pmc_desc[i].default_value
#define PMC_RSVD_MASK(i) pmu_conf.pmc_desc[i].reserved_mask
#define PMD_PMD_DEP(i) pmu_conf.pmd_desc[i].dep_pmd[0]
#define PMC_PMD_DEP(i) pmu_conf.pmc_desc[i].dep_pmd[0]
-/* k assume unsigned */
-#define IBR_IS_IMPL(k) (k<pmu_conf.num_ibrs)
-#define DBR_IS_IMPL(k) (k<pmu_conf.num_dbrs)
+/* k assumed unsigned (up to 64 registers) */
+#define IBR_IS_IMPL(k) (k< IA64_NUM_DBG_REGS)
+#define DBR_IS_IMPL(k) (k< IA64_NUM_DBG_REGS)
-#define CTX_IS_ENABLED(c) ((c)->ctx_flags.state == PFM_CTX_ENABLED)
#define CTX_OVFL_NOBLOCK(c) ((c)->ctx_fl_block == 0)
-#define CTX_INHERIT_MODE(c) ((c)->ctx_fl_inherit)
-#define CTX_HAS_SMPL(c) ((c)->ctx_psb != NULL)
+#define CTX_HAS_SMPL(c) ((c)->ctx_fl_is_sampling)
+#define PFM_CTX_TASK(h) (h)->ctx_task
+
/* XXX: does not support more than 64 PMDs */
#define CTX_USED_PMD(ctx, mask) (ctx)->ctx_used_pmds[0] |= (mask)
#define CTX_IS_USED_PMD(ctx, c) (((ctx)->ctx_used_pmds[0] & (1UL << (c))) != 0UL)
+#define CTX_USED_MONITOR(ctx, mask) (ctx)->ctx_used_monitors[0] |= (mask)
#define CTX_USED_IBR(ctx,n) (ctx)->ctx_used_ibrs[(n)>>6] |= 1UL<< ((n) % 64)
#define CTX_USED_DBR(ctx,n) (ctx)->ctx_used_dbrs[(n)>>6] |= 1UL<< ((n) % 64)
#define CTX_USES_DBREGS(ctx) (((pfm_context_t *)(ctx))->ctx_fl_using_dbreg==1)
+#define PFM_CODE_RR 0 /* requesting code range restriction */
+#define PFM_DATA_RR 1 /* requestion data range restriction */
+
+#define PFM_CPUINFO_CLEAR(v) pfm_get_cpu_var(pfm_syst_info) &= ~(v)
+#define PFM_CPUINFO_SET(v) pfm_get_cpu_var(pfm_syst_info) |= (v)
+#define PFM_CPUINFO_GET() pfm_get_cpu_var(pfm_syst_info)
+
+/*
+ * context protection macros
+ * in SMP:
+ * - we need to protect against CPU concurrency (spin_lock)
+ * - we need to protect against PMU overflow interrupts (local_irq_disable)
+ * in UP:
+ * - we need to protect against PMU overflow interrupts (local_irq_disable)
+ *
+ * spin_lock_irqsave()/spin_lock_irqrestore():
+ * in SMP: local_irq_disable + spin_lock
+ * in UP : local_irq_disable
+ *
+ * spin_lock()/spin_lock():
+ * in UP : removed automatically
+ * in SMP: protect against context accesses from other CPU. interrupts
+ * are not masked. This is useful for the PMU interrupt handler
+ * because we know we will not get PMU concurrency in that code.
+ */
+#define PROTECT_CTX(c, f) \
+ do { \
+ DPRINT(("spinlock_irq_save ctx %p by [%d]\n", c, current->pid)); \
+ spin_lock_irqsave(&(c)->ctx_lock, f); \
+ DPRINT(("spinlocked ctx %p by [%d]\n", c, current->pid)); \
+ } while(0)
+
+#define UNPROTECT_CTX(c, f) \
+ do { \
+ DPRINT(("spinlock_irq_restore ctx %p by [%d]\n", c, current->pid)); \
+ spin_unlock_irqrestore(&(c)->ctx_lock, f); \
+ } while(0)
+
+#define PROTECT_CTX_NOPRINT(c, f) \
+ do { \
+ spin_lock_irqsave(&(c)->ctx_lock, f); \
+ } while(0)
+
+
+#define UNPROTECT_CTX_NOPRINT(c, f) \
+ do { \
+ spin_unlock_irqrestore(&(c)->ctx_lock, f); \
+ } while(0)
+
+
+#define PROTECT_CTX_NOIRQ(c) \
+ do { \
+ spin_lock(&(c)->ctx_lock); \
+ } while(0)
+
+#define UNPROTECT_CTX_NOIRQ(c) \
+ do { \
+ spin_unlock(&(c)->ctx_lock); \
+ } while(0)
+
+
+#ifdef CONFIG_SMP
-#define LOCK_CTX(ctx) spin_lock(&(ctx)->ctx_lock)
-#define UNLOCK_CTX(ctx) spin_unlock(&(ctx)->ctx_lock)
+#define GET_ACTIVATION() pfm_get_cpu_var(pmu_activation_number)
+#define INC_ACTIVATION() pfm_get_cpu_var(pmu_activation_number)++
+#define SET_ACTIVATION(c) (c)->ctx_last_activation = GET_ACTIVATION()
-#define SET_PMU_OWNER(t) do { pmu_owners[smp_processor_id()].owner = (t); } while(0)
-#define PMU_OWNER() pmu_owners[smp_processor_id()].owner
+#else /* !CONFIG_SMP */
+#define SET_ACTIVATION(t) do {} while(0)
+#define GET_ACTIVATION(t) do {} while(0)
+#define INC_ACTIVATION(t) do {} while(0)
+#endif /* CONFIG_SMP */
-#define LOCK_PFS() spin_lock(&pfm_sessions.pfs_lock)
-#define UNLOCK_PFS() spin_unlock(&pfm_sessions.pfs_lock)
+#define SET_PMU_OWNER(t, c) do { pfm_get_cpu_var(pmu_owner) = (t); pfm_get_cpu_var(pmu_ctx) = (c); } while(0)
+#define GET_PMU_OWNER() pfm_get_cpu_var(pmu_owner)
+#define GET_PMU_CTX() pfm_get_cpu_var(pmu_ctx)
+
+#define LOCK_PFS() spin_lock(&pfm_sessions.pfs_lock)
+#define UNLOCK_PFS() spin_unlock(&pfm_sessions.pfs_lock)
#define PFM_REG_RETFLAG_SET(flags, val) do { flags &= ~PFM_REG_RETFL_MASK; flags |= (val); } while(0)
-#define PFM_CPUINFO_CLEAR(v) __get_cpu_var(pfm_syst_info) &= ~(v)
-#define PFM_CPUINFO_SET(v) __get_cpu_var(pfm_syst_info) |= (v)
+#ifdef CONFIG_SMP
+#define PFM_CPU_ONLINE_MAP cpu_online_map
+#define cpu_is_online(i) (PFM_CPU_ONLINE_MAP & (1UL << i))
+#else
+#define PFM_CPU_ONLINE_MAP 1UL
+#define cpu_is_online(i) (i==0)
+#endif
+
+/*
+ * cmp0 must be the value of pmc0
+ */
+#define PMC0_HAS_OVFL(cmp0) (cmp0 & ~0x1UL)
/*
* debugging
*/
-#define DBprintk(a) \
+#define DPRINT(a) \
do { \
- if (pfm_sysctl.debug >0) { printk("%s.%d: CPU%d ", __FUNCTION__, __LINE__, smp_processor_id()); printk a; } \
+ if (unlikely(pfm_sysctl.debug >0)) { printk("%s.%d: CPU%d [%d] ", __FUNCTION__, __LINE__, smp_processor_id(), current->pid); printk a; } \
} while (0)
-#define DBprintk_ovfl(a) \
+#define DPRINT_ovfl(a) \
do { \
- if (pfm_sysctl.debug > 0 && pfm_sysctl.debug_ovfl >0) { printk("%s.%d: CPU%d ", __FUNCTION__, __LINE__, smp_processor_id()); printk a; } \
+ if (unlikely(pfm_sysctl.debug > 0 && pfm_sysctl.debug_ovfl >0)) { printk("%s.%d: CPU%d [%d] ", __FUNCTION__, __LINE__, smp_processor_id(), current->pid); printk a; } \
} while (0)
-
-
-
-/*
+/*
* Architected PMC structure
*/
typedef struct {
} pfm_monitor_t;
/*
- * There is one such data structure per perfmon context. It is used to describe the
- * sampling buffer. It is to be shared among siblings whereas the pfm_context
- * is not.
- * Therefore we maintain a refcnt which is incremented on fork().
- * This buffer is private to the kernel only the actual sampling buffer
- * including its header are exposed to the user. This construct allows us to
- * export the buffer read-write, if needed, without worrying about security
- * problems.
- */
-typedef struct _pfm_smpl_buffer_desc {
- spinlock_t psb_lock; /* protection lock */
- unsigned long psb_refcnt; /* how many users for the buffer */
- int psb_flags; /* bitvector of flags (not yet used) */
-
- void *psb_addr; /* points to location of first entry */
- unsigned long psb_entries; /* maximum number of entries */
- unsigned long psb_size; /* aligned size of buffer */
- unsigned long psb_index; /* next free entry slot XXX: must use the one in buffer */
- unsigned long psb_entry_size; /* size of each entry including entry header */
-
- perfmon_smpl_hdr_t *psb_hdr; /* points to sampling buffer header */
-
- struct _pfm_smpl_buffer_desc *psb_next; /* next psb, used for rvfreeing of psb_hdr */
-
-} pfm_smpl_buffer_desc_t;
-
-/*
- * psb_flags
- */
-#define PSB_HAS_VMA 0x1 /* a virtual mapping for the buffer exists */
-
-#define LOCK_PSB(p) spin_lock(&(p)->psb_lock)
-#define UNLOCK_PSB(p) spin_unlock(&(p)->psb_lock)
-
-/*
* 64-bit software counter structure
*/
typedef struct {
- u64 val; /* virtual 64bit counter value */
- u64 lval; /* last value */
- u64 long_reset; /* reset value on sampling overflow */
- u64 short_reset;/* reset value on overflow */
- u64 reset_pmds[4]; /* which other pmds to reset when this counter overflows */
- u64 seed; /* seed for random-number generator */
- u64 mask; /* mask for random-number generator */
- unsigned int flags; /* notify/do not notify */
+ unsigned long val; /* virtual 64bit counter value */
+ unsigned long lval; /* last reset value */
+ unsigned long long_reset; /* reset value on sampling overflow */
+ unsigned long short_reset; /* reset value on overflow */
+ unsigned long reset_pmds[4]; /* which other pmds to reset when this counter overflows */
+ unsigned long smpl_pmds[4]; /* which pmds are accessed when counter overflow */
+ unsigned long seed; /* seed for random-number generator */
+ unsigned long mask; /* mask for random-number generator */
+ unsigned int flags; /* notify/do not notify */
+ unsigned int reserved; /* for future use */
+ unsigned long eventid; /* overflow event identifier */
} pfm_counter_t;
/*
- * perfmon context. One per process, is cloned on fork() depending on
- * inheritance flags
+ * context flags
*/
typedef struct {
- unsigned int state:1; /* 0=disabled, 1=enabled */
- unsigned int inherit:2; /* inherit mode */
unsigned int block:1; /* when 1, task will blocked on user notifications */
unsigned int system:1; /* do system wide monitoring */
- unsigned int frozen:1; /* pmu must be kept frozen on ctxsw in */
- unsigned int protected:1; /* allow access to creator of context only */
unsigned int using_dbreg:1; /* using range restrictions (debug registers) */
+ unsigned int is_sampling:1; /* true if using a custom format */
unsigned int excl_idle:1; /* exclude idle task in system wide session */
- unsigned int unsecure:1; /* sp = 0 for non self-monitored task */
- unsigned int trap_reason:2; /* reason for going into pfm_block_ovfl_reset() */
- unsigned int reserved:20;
+ unsigned int unsecure:1; /* exclude idle task in system wide session */
+ unsigned int going_zombie:1; /* context is zombie (MASKED+blocking) */
+ unsigned int trap_reason:2; /* reason for going into pfm_handle_work() */
+ unsigned int no_msg:1; /* no message sent on overflow */
+ unsigned int reserved:22;
} pfm_context_flags_t;
#define PFM_TRAP_REASON_NONE 0x0 /* default value */
-#define PFM_TRAP_REASON_BLOCKSIG 0x1 /* we need to block on overflow and signal user */
-#define PFM_TRAP_REASON_SIG 0x2 /* we simply need to signal user */
-#define PFM_TRAP_REASON_RESET 0x3 /* we need to reset PMDs */
+#define PFM_TRAP_REASON_BLOCK 0x1 /* we need to block on overflow */
+#define PFM_TRAP_REASON_RESET 0x2 /* we need to reset PMDs */
+
/*
* perfmon context: encapsulates all the state of a monitoring session
- * XXX: probably need to change layout
*/
+
typedef struct pfm_context {
- pfm_smpl_buffer_desc_t *ctx_psb; /* sampling buffer, if any */
- unsigned long ctx_smpl_vaddr; /* user level virtual address of smpl buffer */
+ spinlock_t ctx_lock; /* context protection */
- spinlock_t ctx_lock;
- pfm_context_flags_t ctx_flags; /* block/noblock */
+ pfm_context_flags_t ctx_flags; /* bitmask of flags (block reason incl.) */
+ unsigned int ctx_state; /* state: active/inactive (no bitfield) */
- struct task_struct *ctx_notify_task; /* who to notify on overflow */
- struct task_struct *ctx_owner; /* pid of creator (debug) */
+ struct task_struct *ctx_task; /* task to which context is attached */
unsigned long ctx_ovfl_regs[4]; /* which registers overflowed (notification) */
- unsigned long ctx_smpl_regs[4]; /* which registers to record on overflow */
struct semaphore ctx_restart_sem; /* use for blocking notification mode */
- unsigned long ctx_used_pmds[4]; /* bitmask of PMD used */
- unsigned long ctx_reload_pmds[4]; /* bitmask of PMD to reload on ctxsw */
+ unsigned long ctx_used_pmds[4]; /* bitmask of PMD used */
+ unsigned long ctx_all_pmds[4]; /* bitmask of all accessible PMDs */
+ unsigned long ctx_reload_pmds[4]; /* bitmask of force reload PMD on ctxsw in */
+
+ unsigned long ctx_all_pmcs[4]; /* bitmask of all accessible PMCs */
+ unsigned long ctx_reload_pmcs[4]; /* bitmask of force reload PMC on ctxsw in */
+ unsigned long ctx_used_monitors[4]; /* bitmask of monitor PMC being used */
+
+ unsigned long ctx_pmcs[IA64_NUM_PMC_REGS]; /* saved copies of PMC values */
+
+ unsigned int ctx_used_ibrs[1]; /* bitmask of used IBR (speedup ctxsw in) */
+ unsigned int ctx_used_dbrs[1]; /* bitmask of used DBR (speedup ctxsw in) */
+ unsigned long ctx_dbrs[IA64_NUM_DBG_REGS]; /* DBR values (cache) when not loaded */
+ unsigned long ctx_ibrs[IA64_NUM_DBG_REGS]; /* IBR values (cache) when not loaded */
+
+ pfm_counter_t ctx_pmds[IA64_NUM_PMD_REGS]; /* software state for PMDS */
- unsigned long ctx_used_pmcs[4]; /* bitmask PMC used by context */
- unsigned long ctx_reload_pmcs[4]; /* bitmask of PMC to reload on ctxsw */
+ u64 ctx_saved_psr; /* copy of psr used for ctxsw */
- unsigned long ctx_used_ibrs[4]; /* bitmask of used IBR (speedup ctxsw) */
- unsigned long ctx_used_dbrs[4]; /* bitmask of used DBR (speedup ctxsw) */
+ unsigned long ctx_last_activation; /* context last activation number for last_cpu */
+ unsigned int ctx_last_cpu; /* CPU id of current or last CPU used (SMP only) */
+ unsigned int ctx_cpu; /* cpu to which perfmon is applied (system wide) */
- pfm_counter_t ctx_soft_pmds[IA64_NUM_PMD_REGS]; /* XXX: size should be dynamic */
+ int ctx_fd; /* file descriptor used my this context */
- u64 ctx_saved_psr; /* copy of psr used for lazy ctxsw */
- unsigned long ctx_saved_cpus_allowed; /* copy of the task cpus_allowed (system wide) */
- unsigned int ctx_cpu; /* CPU used by system wide session */
+ pfm_buffer_fmt_t *ctx_buf_fmt; /* buffer format callbacks */
+ void *ctx_smpl_hdr; /* points to sampling buffer header kernel vaddr */
+ unsigned long ctx_smpl_size; /* size of sampling buffer */
+ void *ctx_smpl_vaddr; /* user level virtual address of smpl buffer */
- atomic_t ctx_last_cpu; /* CPU id of current or last CPU used */
+ wait_queue_head_t ctx_msgq_wait;
+ pfm_msg_t ctx_msgq[PFM_MAX_MSGS];
+ int ctx_msgq_head;
+ int ctx_msgq_tail;
+ struct fasync_struct *ctx_async_queue;
+
+ wait_queue_head_t ctx_zombieq; /* termination cleanup wait queue */
} pfm_context_t;
-#define ctx_fl_inherit ctx_flags.inherit
+/*
+ * magic number used to verify that structure is really
+ * a perfmon context
+ */
+#define PFM_IS_FILE(f) ((f)->f_op == &pfm_file_ops)
+
+#define PFM_GET_CTX(t) ((pfm_context_t *)(t)->thread.pfm_context)
+
+#ifdef CONFIG_SMP
+#define SET_LAST_CPU(ctx, v) (ctx)->ctx_last_cpu = (v)
+#define GET_LAST_CPU(ctx) (ctx)->ctx_last_cpu
+#else
+#define SET_LAST_CPU(ctx, v) do {} while(0)
+#define GET_LAST_CPU(ctx) do {} while(0)
+#endif
+
+
#define ctx_fl_block ctx_flags.block
#define ctx_fl_system ctx_flags.system
-#define ctx_fl_frozen ctx_flags.frozen
-#define ctx_fl_protected ctx_flags.protected
#define ctx_fl_using_dbreg ctx_flags.using_dbreg
+#define ctx_fl_is_sampling ctx_flags.is_sampling
#define ctx_fl_excl_idle ctx_flags.excl_idle
-#define ctx_fl_trap_reason ctx_flags.trap_reason
#define ctx_fl_unsecure ctx_flags.unsecure
+#define ctx_fl_going_zombie ctx_flags.going_zombie
+#define ctx_fl_trap_reason ctx_flags.trap_reason
+#define ctx_fl_no_msg ctx_flags.no_msg
+
+#define PFM_SET_WORK_PENDING(t, v) do { (t)->thread.pfm_needs_checking = v; } while(0);
+#define PFM_GET_WORK_PENDING(t) (t)->thread.pfm_needs_checking
/*
* global information about all sessions
typedef struct {
spinlock_t pfs_lock; /* lock the structure */
- unsigned int pfs_task_sessions; /* number of per task sessions */
+ unsigned int pfs_task_sessions; /* number of per task sessions */
unsigned int pfs_sys_sessions; /* number of per system wide sessions */
unsigned int pfs_sys_use_dbregs; /* incremented when a system wide session uses debug regs */
unsigned int pfs_ptrace_use_dbregs; /* incremented when a process uses debug regs */
/*
* information about a PMC or PMD.
- * dep_pmd[]: a bitmask of dependent PMD registers
+ * dep_pmd[]: a bitmask of dependent PMD registers
* dep_pmc[]: a bitmask of dependent PMC registers
*/
typedef struct {
int pm_pos;
unsigned long default_value; /* power-on default value */
unsigned long reserved_mask; /* bitmask of reserved bits */
- int (*read_check)(struct task_struct *task, unsigned int cnum, unsigned long *val, struct pt_regs *regs);
- int (*write_check)(struct task_struct *task, unsigned int cnum, unsigned long *val, struct pt_regs *regs);
+ int (*read_check)(struct task_struct *task, pfm_context_t *ctx, unsigned int cnum, unsigned long *val, struct pt_regs *regs);
+ int (*write_check)(struct task_struct *task, pfm_context_t *ctx, unsigned int cnum, unsigned long *val, struct pt_regs *regs);
unsigned long dep_pmd[4];
unsigned long dep_pmc[4];
} pfm_reg_desc_t;
* a description of the PMU main characteristics.
*/
typedef struct {
- unsigned int disabled; /* indicates if perfmon is working properly */
- unsigned long ovfl_val; /* overflow value for generic counters */
- unsigned long impl_pmcs[4]; /* bitmask of implemented PMCS */
- unsigned long impl_pmds[4]; /* bitmask of implemented PMDS */
- unsigned int num_pmcs; /* number of implemented PMCS */
- unsigned int num_pmds; /* number of implemented PMDS */
- unsigned int num_ibrs; /* number of implemented IBRS */
- unsigned int num_dbrs; /* number of implemented DBRS */
- unsigned int num_counters; /* number of PMD/PMC counters */
+ unsigned long ovfl_val; /* overflow value for counters */
+
pfm_reg_desc_t *pmc_desc; /* detailed PMC register dependencies descriptions */
pfm_reg_desc_t *pmd_desc; /* detailed PMD register dependencies descriptions */
+
+ unsigned int num_pmcs; /* number of PMCS: computed at init time */
+ unsigned int num_pmds; /* number of PMDS: computed at init time */
+ unsigned long impl_pmcs[4]; /* bitmask of implemented PMCS */
+ unsigned long impl_pmds[4]; /* bitmask of implemented PMDS */
+
+ char *pmu_name; /* PMU family name */
+ unsigned int enabled; /* indicates if perfmon initialized properly */
+ unsigned int pmu_family; /* cpuid family pattern used to identify pmu */
+
+ unsigned int num_ibrs; /* number of IBRS: computed at init time */
+ unsigned int num_dbrs; /* number of DBRS: computed at init time */
+ unsigned int num_counters; /* PMC/PMD counting pairs : computed at init time */
+
+ unsigned int use_rr_dbregs:1; /* set if debug registers used for range restriction */
} pmu_config_t;
/*
- * structure used to pass argument to/from remote CPU
- * using IPI to check and possibly save the PMU context on SMP systems.
- *
- * not used in UP kernels
+ * debug register related type definitions
*/
typedef struct {
- struct task_struct *task; /* which task we are interested in */
- int retval; /* return value of the call: 0=you can proceed, 1=need to wait for completion */
-} pfm_smp_ipi_arg_t;
+ unsigned long ibr_mask:56;
+ unsigned long ibr_plm:4;
+ unsigned long ibr_ig:3;
+ unsigned long ibr_x:1;
+} ibr_mask_reg_t;
+
+typedef struct {
+ unsigned long dbr_mask:56;
+ unsigned long dbr_plm:4;
+ unsigned long dbr_ig:2;
+ unsigned long dbr_w:1;
+ unsigned long dbr_r:1;
+} dbr_mask_reg_t;
+
+typedef union {
+ unsigned long val;
+ ibr_mask_reg_t ibr;
+ dbr_mask_reg_t dbr;
+} dbreg_t;
+
/*
* perfmon command descriptions
*/
typedef struct {
- int (*cmd_func)(struct task_struct *task, pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs);
+ int (*cmd_func)(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs);
+ char *cmd_name;
int cmd_flags;
unsigned int cmd_narg;
size_t cmd_argsize;
+ int (*cmd_getsize)(void *arg, size_t *sz);
} pfm_cmd_desc_t;
-#define PFM_CMD_PID 0x1 /* command requires pid argument */
-#define PFM_CMD_ARG_READ 0x2 /* command must read argument(s) */
-#define PFM_CMD_ARG_RW 0x4 /* command must read/write argument(s) */
-#define PFM_CMD_CTX 0x8 /* command needs a perfmon context */
-#define PFM_CMD_NOCHK 0x10 /* command does not need to check task's state */
+#define PFM_CMD_FD 0x01 /* command requires a file descriptor */
+#define PFM_CMD_ARG_READ 0x02 /* command must read argument(s) */
+#define PFM_CMD_ARG_RW 0x04 /* command must read/write argument(s) */
+#define PFM_CMD_STOP 0x08 /* command does not work on zombie context */
-#define PFM_CMD_IDX(cmd) (cmd)
-#define PFM_CMD_IS_VALID(cmd) ((PFM_CMD_IDX(cmd) >= 0) \
- && (PFM_CMD_IDX(cmd) < (int) PFM_CMD_COUNT) \
- && pfm_cmd_tab[PFM_CMD_IDX(cmd)].cmd_func != NULL)
+#define PFM_CMD_IDX(cmd) (cmd)
+#define PFM_CMD_IS_VALID(cmd) ((PFM_CMD_IDX(cmd) >= 0) && (PFM_CMD_IDX(cmd) < PFM_CMD_COUNT) \
+ && pfm_cmd_tab[PFM_CMD_IDX(cmd)].cmd_func != NULL)
-#define PFM_CMD_USE_PID(cmd) ((pfm_cmd_tab[PFM_CMD_IDX(cmd)].cmd_flags & PFM_CMD_PID) != 0)
-#define PFM_CMD_READ_ARG(cmd) ((pfm_cmd_tab[PFM_CMD_IDX(cmd)].cmd_flags & PFM_CMD_ARG_READ) != 0)
-#define PFM_CMD_RW_ARG(cmd) ((pfm_cmd_tab[PFM_CMD_IDX(cmd)].cmd_flags & PFM_CMD_ARG_RW) != 0)
-#define PFM_CMD_USE_CTX(cmd) ((pfm_cmd_tab[PFM_CMD_IDX(cmd)].cmd_flags & PFM_CMD_CTX) != 0)
-#define PFM_CMD_CHK(cmd) ((pfm_cmd_tab[PFM_CMD_IDX(cmd)].cmd_flags & PFM_CMD_NOCHK) == 0)
+#define PFM_CMD_NAME(cmd) pfm_cmd_tab[PFM_CMD_IDX(cmd)].cmd_name
+#define PFM_CMD_READ_ARG(cmd) (pfm_cmd_tab[PFM_CMD_IDX(cmd)].cmd_flags & PFM_CMD_ARG_READ)
+#define PFM_CMD_RW_ARG(cmd) (pfm_cmd_tab[PFM_CMD_IDX(cmd)].cmd_flags & PFM_CMD_ARG_RW)
+#define PFM_CMD_USE_FD(cmd) (pfm_cmd_tab[PFM_CMD_IDX(cmd)].cmd_flags & PFM_CMD_FD)
+#define PFM_CMD_STOPPED(cmd) (pfm_cmd_tab[PFM_CMD_IDX(cmd)].cmd_flags & PFM_CMD_STOP)
#define PFM_CMD_ARG_MANY -1 /* cannot be zero */
#define PFM_CMD_NARG(cmd) (pfm_cmd_tab[PFM_CMD_IDX(cmd)].cmd_narg)
#define PFM_CMD_ARG_SIZE(cmd) (pfm_cmd_tab[PFM_CMD_IDX(cmd)].cmd_argsize)
+#define PFM_CMD_GETSIZE(cmd) (pfm_cmd_tab[PFM_CMD_IDX(cmd)].cmd_getsize)
typedef struct {
int debug; /* turn on/off debugging via syslog */
int debug_ovfl; /* turn on/off debug printk in overflow handler */
int fastctxsw; /* turn on/off fast (unsecure) ctxsw */
+ int debug_pfm_read;
} pfm_sysctl_t;
typedef struct {
- unsigned long pfm_spurious_ovfl_intr_count; /* keep track of spurious ovfl interrupts */
- unsigned long pfm_ovfl_intr_count; /* keep track of ovfl interrupts */
- unsigned long pfm_recorded_samples_count;
- unsigned long pfm_full_smpl_buffer_count; /* how many times the sampling buffer was full */
+ unsigned long pfm_spurious_ovfl_intr_count; /* keep track of spurious ovfl interrupts */
+ unsigned long pfm_ovfl_intr_count; /* keep track of ovfl interrupts */
+ unsigned long pfm_ovfl_intr_cycles; /* cycles spent processing ovfl interrupts */
+ unsigned long pfm_ovfl_intr_cycles_min; /* min cycles spent processing ovfl interrupts */
+ unsigned long pfm_ovfl_intr_cycles_max; /* max cycles spent processing ovfl interrupts */
+ unsigned long pfm_sysupdt_count;
+ unsigned long pfm_sysupdt_cycles;
+ unsigned long pfm_smpl_handler_calls;
+ unsigned long pfm_smpl_handler_cycles;
char pad[SMP_CACHE_BYTES] ____cacheline_aligned;
} pfm_stats_t;
/*
* perfmon internal variables
*/
-static pfm_session_t pfm_sessions; /* global sessions information */
-static struct proc_dir_entry *perfmon_dir; /* for debug only */
-static pfm_stats_t pfm_stats[NR_CPUS];
-static pfm_intr_handler_desc_t *pfm_alternate_intr_handler;
+static pfm_stats_t pfm_stats[NR_CPUS];
+static pfm_session_t pfm_sessions; /* global sessions information */
-DEFINE_PER_CPU(unsigned long, pfm_syst_info);
+static struct proc_dir_entry *perfmon_dir;
+static pfm_uuid_t pfm_null_uuid = {0,};
+
+static spinlock_t pfm_smpl_fmt_lock;
+static pfm_buffer_fmt_t *pfm_buffer_fmt_list;
+#define LOCK_BUF_FMT_LIST() spin_lock(&pfm_smpl_fmt_lock)
+#define UNLOCK_BUF_FMT_LIST() spin_unlock(&pfm_smpl_fmt_lock)
/* sysctl() controls */
static pfm_sysctl_t pfm_sysctl;
+int pfm_debug_var;
static ctl_table pfm_ctl_table[]={
{1, "debug", &pfm_sysctl.debug, sizeof(int), 0666, NULL, &proc_dointvec, NULL,},
static void pfm_vm_close(struct vm_area_struct * area);
static struct vm_operations_struct pfm_vm_ops={
- .close = pfm_vm_close
+ close: pfm_vm_close
};
/*
- * keep track of task owning the PMU per CPU.
+ * Linux 2.5 vs. 2.4 helper macros and definitions
+ *
+ * if not at least 2.5.69, then assume 2.4.x.
*/
-static struct {
- struct task_struct *owner;
- char pad[SMP_CACHE_BYTES] ____cacheline_aligned;
-} pmu_owners[NR_CPUS];
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,69)
+
+#define PFM_COMPILED_FOR_2_4 1
+
+#include <linux/wrapper.h>
+
+#define pfm_get_cpu_var(v) local_cpu_data->v
+#define pfm_get_cpu_data(a,b) cpu_data((b))->a
+typedef void pfm_irq_handler_t;
+#define PFM_IRQ_HANDLER_RET(v)
+
+#define DEFINE_PER_CPU(a,b)
+
+static inline int
+pfm_wait_task_inactive(struct task_struct *task)
+{
+#ifdef CONFIG_SMP
+ /* Make sure the child gets off its CPU.. */
+ for (;;) {
+ task_lock(task);
+ if (!task_has_cpu(task)) break;
+ task_unlock(task);
+ do {
+ if (task->state != TASK_STOPPED)
+ return -ESRCH;
+ barrier();
+ cpu_relax();
+ } while (task_has_cpu(task));
+ }
+ task_unlock(task);
+#endif
+ return 0;
+}
+
+static inline void
+pfm_put_task(struct task_struct *task)
+{
+ if (task != current) free_task_struct(task);
+}
+
+static inline void
+pfm_set_task_notify(struct task_struct *task)
+{
+}
+
+static inline void
+pfm_clear_task_notify(void)
+{
+}
+
+static inline void
+pfm_reserve_page(unsigned long a)
+{
+ unsigned long page;
+
+ page = ia64_tpa(a);
+ mem_map_reserve(virt_to_page(__va(page)));
+}
+
+static inline void
+pfm_unreserve_page(unsigned long a)
+{
+ unsigned long page;
+
+ page = ia64_tpa(a);
+ mem_map_unreserve(virt_to_page(__va(page)));
+}
+
+static inline int
+pfm_remap_page_range(struct vm_area_struct *vma, unsigned long from, unsigned long phys_addr, unsigned long size, pgprot_t prot)
+{
+ return remap_page_range(from, phys_addr, size, prot);
+}
+
+static inline unsigned long
+pfm_protect_ctx_ctxsw(pfm_context_t *x)
+{
+ unsigned long f;
+ spin_lock(&(x)->ctx_lock);
+ return f;
+}
+
+static inline unsigned long
+pfm_unprotect_ctx_ctxsw(pfm_context_t *x, unsigned long f)
+{
+ spin_unlock(&(x)->ctx_lock);
+}
+
+#else /* 2.5.69 or higher */
+
+#define pfm_wait_task_inactive(t) wait_task_inactive(t)
+#define pfm_get_cpu_var(v) __get_cpu_var(v)
+#define pfm_get_cpu_data(a,b) per_cpu(a, b)
+typedef irqreturn_t pfm_irq_handler_t;
+#define PFM_IRQ_HANDLER_RET(v) do { \
+ put_cpu_no_resched(); \
+ return IRQ_HANDLED; \
+ } while(0);
+
+static inline void
+pfm_put_task(struct task_struct *task)
+{
+ if (task != current) put_task_struct(task);
+}
+
+static inline void
+pfm_set_task_notify(struct task_struct *task)
+{
+ struct thread_info *info;
+
+ info = (struct thread_info *) ((char *) task + IA64_TASK_SIZE);
+ set_bit(TIF_NOTIFY_RESUME, &info->flags);
+}
+
+static inline void
+pfm_clear_task_notify(void)
+{
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+}
+
+static inline void
+pfm_reserve_page(unsigned long a)
+{
+ SetPageReserved(vmalloc_to_page((void *)a));
+}
+static inline void
+pfm_unreserve_page(unsigned long a)
+{
+ ClearPageReserved(vmalloc_to_page((void*)a));
+}
+
+static inline int
+pfm_remap_page_range(struct vm_area_struct *vma, unsigned long from, unsigned long phys_addr, unsigned long size, pgprot_t prot)
+{
+ return remap_page_range(vma, from, phys_addr, size, prot);
+}
+
+static inline unsigned long
+pfm_protect_ctx_ctxsw(pfm_context_t *x)
+{
+ spin_lock_irq(&(x)->ctx_lock);
+ return 0UL;
+}
+
+static inline unsigned long
+pfm_unprotect_ctx_ctxsw(pfm_context_t *x, unsigned long f)
+{
+ spin_unlock(&(x)->ctx_lock);
+}
+
+#endif /* 2.5 vs. 2.4 */
+
+DEFINE_PER_CPU(unsigned long, pfm_syst_info);
+DEFINE_PER_CPU(struct task_struct *, pmu_owner);
+DEFINE_PER_CPU(pfm_context_t *, pmu_ctx);
+DEFINE_PER_CPU(unsigned long, pmu_activation_number);
+/* forward declaration */
+static struct file_operations pfm_file_ops;
/*
* forward declarations
*/
-static void pfm_reset_pmu(struct task_struct *);
+#ifndef CONFIG_SMP
static void pfm_lazy_save_regs (struct task_struct *ta);
+#endif
#if defined(CONFIG_ITANIUM)
#include "perfmon_itanium.h"
#include "perfmon_generic.h"
#endif
+static int pfm_end_notify_user(pfm_context_t *ctx);
+
static inline void
pfm_clear_psr_pp(void)
{
ia64_srlz_d();
}
+/*
+ * PMD[i] must be a counter. no check is made
+ */
static inline unsigned long
pfm_read_soft_counter(pfm_context_t *ctx, int i)
{
- return ctx->ctx_soft_pmds[i].val + (ia64_get_pmd(i) & pmu_conf.ovfl_val);
+ return ctx->ctx_pmds[i].val + (ia64_get_pmd(i) & pmu_conf.ovfl_val);
}
+/*
+ * PMD[i] must be a counter. no check is made
+ */
static inline void
pfm_write_soft_counter(pfm_context_t *ctx, int i, unsigned long val)
{
- ctx->ctx_soft_pmds[i].val = val & ~pmu_conf.ovfl_val;
+ ctx->ctx_pmds[i].val = val & ~pmu_conf.ovfl_val;
/*
* writing to unimplemented part is ignore, so we do not need to
* mask off top part
ia64_set_pmd(i, val & pmu_conf.ovfl_val);
}
-/*
- * Generates a unique (per CPU) timestamp
- */
-static inline unsigned long
-pfm_get_stamp(void)
+static pfm_msg_t *
+pfm_get_new_msg(pfm_context_t *ctx)
+{
+ int idx, next;
+
+ next = (ctx->ctx_msgq_tail+1) % PFM_MAX_MSGS;
+
+ DPRINT(("ctx_fd=%p head=%d tail=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail));
+ if (next == ctx->ctx_msgq_head) return NULL;
+
+ idx = ctx->ctx_msgq_tail;
+ ctx->ctx_msgq_tail = next;
+
+ DPRINT(("ctx=%p head=%d tail=%d msg=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail, idx));
+
+ return ctx->ctx_msgq+idx;
+}
+
+static pfm_msg_t *
+pfm_get_next_msg(pfm_context_t *ctx)
{
+ pfm_msg_t *msg;
+
+ DPRINT(("ctx=%p head=%d tail=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail));
+
+ if (PFM_CTXQ_EMPTY(ctx)) return NULL;
+
+ /*
+ * get oldest message
+ */
+ msg = ctx->ctx_msgq+ctx->ctx_msgq_head;
+
/*
- * XXX: must find something more efficient
+ * and move forward
*/
- return ia64_get_itc();
+ ctx->ctx_msgq_head = (ctx->ctx_msgq_head+1) % PFM_MAX_MSGS;
+
+ DPRINT(("ctx=%p head=%d tail=%d type=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail, msg->pfm_gen_msg.msg_type));
+
+ return msg;
+}
+
+static void
+pfm_reset_msgq(pfm_context_t *ctx)
+{
+ ctx->ctx_msgq_head = ctx->ctx_msgq_tail = 0;
+ DPRINT(("ctx=%p msgq reset\n", ctx));
}
+
/* Here we want the physical address of the memory.
* This is used when initializing the contents of the
* area and marking the pages as reserved.
pfm_kvirt_to_pa(unsigned long adr)
{
__u64 pa = ia64_tpa(adr);
- //DBprintk(("kv2pa(%lx-->%lx)\n", adr, pa));
return pa;
}
pfm_rvmalloc(unsigned long size)
{
void *mem;
- unsigned long adr;
+ unsigned long addr;
- size=PAGE_ALIGN(size);
- mem=vmalloc(size);
+ size = PAGE_ALIGN(size);
+ mem = vmalloc(size);
if (mem) {
//printk("perfmon: CPU%d pfm_rvmalloc(%ld)=%p\n", smp_processor_id(), size, mem);
- memset(mem, 0, size); /* Clear the ram out, no junk to the user */
- adr=(unsigned long) mem;
+ memset(mem, 0, size);
+ addr = (unsigned long)mem;
while (size > 0) {
- SetPageReserved(vmalloc_to_page((void *)adr));
- adr+=PAGE_SIZE;
+ pfm_reserve_page(addr);
+ addr+=PAGE_SIZE;
size-=PAGE_SIZE;
}
}
static void
pfm_rvfree(void *mem, unsigned long size)
{
- unsigned long adr;
+ unsigned long addr;
if (mem) {
- adr=(unsigned long) mem;
+ DPRINT(("freeing physical buffer @%p size=%lu\n", mem, size));
+ addr = (unsigned long) mem;
while ((long) size > 0) {
- ClearPageReserved(vmalloc_to_page((void*)adr));
- adr+=PAGE_SIZE;
+ pfm_unreserve_page(addr);
+ addr+=PAGE_SIZE;
size-=PAGE_SIZE;
}
vfree(mem);
return;
}
-/*
- * This function gets called from mm/mmap.c:exit_mmap() only when there is a sampling buffer
- * attached to the context AND the current task has a mapping for it, i.e., it is the original
- * creator of the context.
- *
- * This function is used to remember the fact that the vma describing the sampling buffer
- * has now been removed. It can only be called when no other tasks share the same mm context.
- *
- */
-static void
-pfm_vm_close(struct vm_area_struct *vma)
+static pfm_context_t *
+pfm_context_alloc(void)
{
- pfm_smpl_buffer_desc_t *psb = (pfm_smpl_buffer_desc_t *)vma->vm_private_data;
+ pfm_context_t *ctx;
- if (psb == NULL) {
- printk(KERN_DEBUG "perfmon: psb is null in [%d]\n", current->pid);
- return;
+ /* allocate context descriptor */
+ ctx = kmalloc(sizeof(pfm_context_t), GFP_KERNEL);
+ if (ctx) {
+ memset(ctx, 0, sizeof(pfm_context_t));
+ DPRINT(("alloc ctx @%p\n", ctx));
}
- /*
- * Add PSB to list of buffers to free on release_thread() when no more users
- *
- * This call is safe because, once the count is zero is cannot be modified anymore.
- * This is not because there is no more user of the mm context, that the sampling
- * buffer is not being used anymore outside of this task. In fact, it can still
- * be accessed from within the kernel by another task (such as the monitored task).
- *
- * Therefore, we only move the psb into the list of buffers to free when we know
- * nobody else is using it.
- * The linked list if independent of the perfmon context, because in the case of
- * multi-threaded processes, the last thread may not have been involved with
- * monitoring however it will be the one removing the vma and it should therefore
- * also remove the sampling buffer. This buffer cannot be removed until the vma
- * is removed.
- *
- * This function cannot remove the buffer from here, because exit_mmap() must first
- * complete. Given that there is no other vma related callback in the generic code,
- * we have created our own with the linked list of sampling buffers to free. The list
- * is part of the thread structure. In release_thread() we check if the list is
- * empty. If not we call into perfmon to free the buffer and psb. That is the only
- * way to ensure a safe deallocation of the sampling buffer which works when
- * the buffer is shared between distinct processes or with multi-threaded programs.
- *
- * We need to lock the psb because the refcnt test and flag manipulation must
- * looked like an atomic operation vis a vis pfm_context_exit()
- */
- LOCK_PSB(psb);
-
- if (psb->psb_refcnt == 0) {
-
- psb->psb_next = current->thread.pfm_smpl_buf_list;
- current->thread.pfm_smpl_buf_list = psb;
+ return ctx;
+}
- DBprintk(("[%d] add smpl @%p size %lu to smpl_buf_list psb_flags=0x%x\n",
- current->pid, psb->psb_hdr, psb->psb_size, psb->psb_flags));
+static void
+pfm_context_free(pfm_context_t *ctx)
+{
+ if (ctx) {
+ DPRINT(("free ctx @%p\n", ctx));
+ kfree(ctx);
}
- DBprintk(("[%d] clearing psb_flags=0x%x smpl @%p size %lu\n",
- current->pid, psb->psb_flags, psb->psb_hdr, psb->psb_size));
- /*
- * decrement the number vma for the buffer
- */
- psb->psb_flags &= ~PSB_HAS_VMA;
-
- UNLOCK_PSB(psb);
}
-/*
- * This function is called from pfm_destroy_context() and also from pfm_inherit()
- * to explicitly remove the sampling buffer mapping from the user level address space.
- */
-static int
-pfm_remove_smpl_mapping(struct task_struct *task)
+static void
+pfm_mask_monitoring(struct task_struct *task)
{
- pfm_context_t *ctx = task->thread.pfm_context;
- pfm_smpl_buffer_desc_t *psb;
- int r;
+ pfm_context_t *ctx = PFM_GET_CTX(task);
+ struct thread_struct *th = &task->thread;
+ unsigned long mask, val;
+ int i;
+
+ DPRINT(("[%d] masking monitoring for [%d]\n", current->pid, task->pid));
/*
- * some sanity checks first
+ * monitoring can only be masked as a result of a valid
+ * counter overflow. In UP, it means that the PMU still
+ * has an owner. Note that the owner can be different
+ * from the current task. However the PMU state belongs
+ * to the owner.
+ * In SMP, a valid overflow only happens when task is
+ * current. Therefore if we come here, we know that
+ * the PMU state belongs to the current task, therefore
+ * we can access the live registers.
+ *
+ * So in both cases, the live register contains the owner's
+ * state. We can ONLY touch the PMU registers and NOT the PSR.
+ *
+ * As a consequence to this call, the thread->pmds[] array
+ * contains stale information which must be ignored
+ * when context is reloaded AND monitoring is active (see
+ * pfm_restart).
*/
- if (ctx == NULL || task->mm == NULL || ctx->ctx_smpl_vaddr == 0 || ctx->ctx_psb == NULL) {
- printk(KERN_DEBUG "perfmon: invalid context mm=%p\n", task->mm);
- return -1;
+ mask = ctx->ctx_used_pmds[0];
+ for (i = 0; mask; i++, mask>>=1) {
+ /* skip non used pmds */
+ if ((mask & 0x1) == 0) continue;
+ val = ia64_get_pmd(i);
+
+ if (PMD_IS_COUNTING(i)) {
+ /*
+ * we rebuild the full 64 bit value of the counter
+ */
+ ctx->ctx_pmds[i].val += (val & pmu_conf.ovfl_val);
+ } else {
+ ctx->ctx_pmds[i].val = val;
+ }
+ DPRINT(("pmd[%d]=0x%lx hw_pmd=0x%lx\n",
+ i,
+ ctx->ctx_pmds[i].val,
+ val & pmu_conf.ovfl_val));
+ }
+ /*
+ * mask monitoring by setting the privilege level to 0
+ * we cannot use psr.pp/psr.up for this, it is controlled by
+ * the user
+ *
+ * if task is current, modify actual registers, otherwise modify
+ * thread save state, i.e., what will be restored in pfm_load_regs()
+ */
+ mask = ctx->ctx_used_monitors[0] >> PMU_FIRST_COUNTER;
+ for(i= PMU_FIRST_COUNTER; mask; i++, mask>>=1) {
+ if ((mask & 0x1) == 0UL) continue;
+ ia64_set_pmc(i, th->pmcs[i] & ~0xfUL);
+ th->pmcs[i] &= ~0xfUL;
+ }
+ /*
+ * make all of this visible
+ */
+ ia64_srlz_d();
+}
+
+/*
+ * must always be done with task == current
+ *
+ * context must be in MASKED state when calling
+ */
+static void
+pfm_restore_monitoring(struct task_struct *task)
+{
+ pfm_context_t *ctx = PFM_GET_CTX(task);
+ struct thread_struct *th = &task->thread;
+ unsigned long mask;
+ unsigned long psr, val;
+ int i;
+
+ if (task != current) {
+ printk(KERN_ERR "perfmon.%d: invalid task[%d] current[%d]\n", __LINE__, task->pid, current->pid);
+ return;
+ }
+ if (CTX_IS_MASKED(ctx) == 0) {
+ printk(KERN_ERR "perfmon.%d: task[%d] current[%d] invalid state=%d\n", __LINE__,
+ task->pid, current->pid, ctx->ctx_state);
+ return;
+ }
+ psr = pfm_get_psr();
+ /*
+ * monitoring is masked via the PMC.
+ * As we restore their value, we do not want each counter to
+ * restart right away. We stop monitoring using the PSR,
+ * restore the PMC (and PMD) and then re-establish the psr
+ * as it was. Note that there can be no pending overflow at
+ * this point, because monitoring was MASKED.
+ *
+ * system-wide session are pinned and self-monitoring
+ */
+ if (ctx->ctx_fl_system && (PFM_CPUINFO_GET() & PFM_CPUINFO_DCR_PP)) {
+ /* disable dcr pp */
+ ia64_set_dcr(ia64_get_dcr() & ~IA64_DCR_PP);
+ pfm_clear_psr_pp();
+ } else {
+ pfm_clear_psr_up();
+ }
+ /*
+ * first, we restore the PMD
+ */
+ mask = ctx->ctx_used_pmds[0];
+ for (i = 0; mask; i++, mask>>=1) {
+ /* skip non used pmds */
+ if ((mask & 0x1) == 0) continue;
+
+ if (PMD_IS_COUNTING(i)) {
+ /*
+ * we split the 64bit value according to
+ * counter width
+ */
+ val = ctx->ctx_pmds[i].val & pmu_conf.ovfl_val;
+ ctx->ctx_pmds[i].val &= ~pmu_conf.ovfl_val;
+ } else {
+ val = ctx->ctx_pmds[i].val;
+ }
+ ia64_set_pmd(i, val);
+
+ DPRINT(("pmd[%d]=0x%lx hw_pmd=0x%lx\n",
+ i,
+ ctx->ctx_pmds[i].val,
+ val));
+ }
+ /*
+ * restore the PMCs
+ */
+ mask = ctx->ctx_used_monitors[0] >> PMU_FIRST_COUNTER;
+ for(i= PMU_FIRST_COUNTER; mask; i++, mask>>=1) {
+ if ((mask & 0x1) == 0UL) continue;
+ th->pmcs[i] = ctx->ctx_pmcs[i];
+ ia64_set_pmc(i, th->pmcs[i]);
+ DPRINT(("[%d] pmc[%d]=0x%lx\n", task->pid, i, th->pmcs[i]));
+ }
+ ia64_srlz_d();
+
+ /*
+ * now restore PSR
+ */
+ if (ctx->ctx_fl_system && (PFM_CPUINFO_GET() & PFM_CPUINFO_DCR_PP)) {
+ /* enable dcr pp */
+ ia64_set_dcr(ia64_get_dcr() | IA64_DCR_PP);
+ ia64_srlz_i();
+ }
+ pfm_set_psr_l(psr);
+}
+
+static inline void
+pfm_save_pmds(unsigned long *pmds, unsigned long mask)
+{
+ int i;
+
+ ia64_srlz_d();
+
+ for (i=0; mask; i++, mask>>=1) {
+ if (mask & 0x1) pmds[i] = ia64_get_pmd(i);
+ }
+}
+
+/*
+ * reload from thread state (used for ctxw only)
+ */
+static inline void
+pfm_restore_pmds(unsigned long *pmds, unsigned long mask)
+{
+ int i;
+ unsigned long val, ovfl_val = pmu_conf.ovfl_val;
+
+ DPRINT(("mask=0x%lx\n", mask));
+ for (i=0; mask; i++, mask>>=1) {
+ if ((mask & 0x1) == 0) continue;
+ val = PMD_IS_COUNTING(i) ? pmds[i] & ovfl_val : pmds[i];
+ ia64_set_pmd(i, val);
+ DPRINT(("pmd[%d]=0x%lx\n", i, val));
+ }
+ ia64_srlz_d();
+}
+
+/*
+ * propagate PMD from context to thread-state
+ */
+static inline void
+pfm_copy_pmds(struct task_struct *task, pfm_context_t *ctx)
+{
+ struct thread_struct *thread = &task->thread;
+ unsigned long ovfl_val = pmu_conf.ovfl_val;
+ unsigned long mask = ctx->ctx_all_pmds[0];
+ unsigned long val;
+ int i;
+
+ DPRINT(("mask=0x%lx\n", mask));
+
+ for (i=0; mask; i++, mask>>=1) {
+
+ val = ctx->ctx_pmds[i].val;
+
+ /*
+ * We break up the 64 bit value into 2 pieces
+ * the lower bits go to the machine state in the
+ * thread (will be reloaded on ctxsw in).
+ * The upper part stays in the soft-counter.
+ */
+ if (PMD_IS_COUNTING(i)) {
+ ctx->ctx_pmds[i].val = val & ~ovfl_val;
+ val &= ovfl_val;
+ }
+ thread->pmds[i] = val;
+
+ DPRINT(("pmd[%d]=0x%lx soft_val=0x%lx\n",
+ i,
+ thread->pmds[i],
+ ctx->ctx_pmds[i].val));
+ }
+}
+
+/*
+ * propagate PMC from context to thread-state
+ */
+static inline void
+pfm_copy_pmcs(struct task_struct *task, pfm_context_t *ctx)
+{
+ struct thread_struct *thread = &task->thread;
+ unsigned long mask = ctx->ctx_all_pmcs[0];
+ int i;
+
+ DPRINT(("mask=0x%lx\n", mask));
+
+ for (i=0; mask; i++, mask>>=1) {
+ /* masking 0 with ovfl_val yields 0 */
+ thread->pmcs[i] = ctx->ctx_pmcs[i];
+ DPRINT(("pmc[%d]=0x%lx\n", i, thread->pmcs[i]));
+ }
+}
+
+
+
+static inline void
+pfm_restore_pmcs(unsigned long *pmcs, unsigned long mask)
+{
+ int i;
+
+ DPRINT(("mask=0x%lx\n", mask));
+ for (i=0; mask; i++, mask>>=1) {
+ if ((mask & 0x1) == 0) continue;
+ ia64_set_pmc(i, pmcs[i]);
+ DPRINT(("pmc[%d]=0x%lx\n", i, pmcs[i]));
+ }
+ ia64_srlz_d();
+}
+
+static inline void
+pfm_restore_ibrs(unsigned long *ibrs, unsigned int nibrs)
+{
+ int i;
+
+ for (i=0; i < nibrs; i++) {
+ ia64_set_ibr(i, ibrs[i]);
+ }
+ ia64_srlz_i();
+}
+
+static inline void
+pfm_restore_dbrs(unsigned long *dbrs, unsigned int ndbrs)
+{
+ int i;
+
+ for (i=0; i < ndbrs; i++) {
+ ia64_set_dbr(i, dbrs[i]);
+ }
+ ia64_srlz_d();
+}
+
+static inline int
+pfm_uuid_cmp(pfm_uuid_t a, pfm_uuid_t b)
+{
+ return memcmp(a, b, sizeof(pfm_uuid_t));
+}
+
+static inline int
+pfm_buf_fmt_exit(pfm_buffer_fmt_t *fmt, struct task_struct *task, void *buf, struct pt_regs *regs)
+{
+ int ret = 0;
+ if (fmt->fmt_exit) ret = (*fmt->fmt_exit)(task, buf, regs);
+ return ret;
+}
+
+static inline int
+pfm_buf_fmt_getsize(pfm_buffer_fmt_t *fmt, struct task_struct *task, unsigned int flags, int cpu, void *arg, unsigned long *size)
+{
+ int ret = 0;
+ if (fmt->fmt_getsize) ret = (*fmt->fmt_getsize)(task, flags, cpu, arg, size);
+ return ret;
+}
+
+
+static inline int
+pfm_buf_fmt_validate(pfm_buffer_fmt_t *fmt, struct task_struct *task, unsigned int flags,
+ int cpu, void *arg)
+{
+ int ret = 0;
+ if (fmt->fmt_validate) ret = (*fmt->fmt_validate)(task, flags, cpu, arg);
+ return ret;
+}
+
+static inline int
+pfm_buf_fmt_init(pfm_buffer_fmt_t *fmt, struct task_struct *task, void *buf, unsigned int flags,
+ int cpu, void *arg)
+{
+ int ret = 0;
+ if (fmt->fmt_init) ret = (*fmt->fmt_init)(task, buf, flags, cpu, arg);
+ return ret;
+}
+
+static inline int
+pfm_buf_fmt_restart(pfm_buffer_fmt_t *fmt, struct task_struct *task, pfm_ovfl_ctrl_t *ctrl, void *buf, struct pt_regs *regs)
+{
+ int ret = 0;
+ if (fmt->fmt_restart) ret = (*fmt->fmt_restart)(task, ctrl, buf, regs);
+ return ret;
+}
+
+static inline int
+pfm_buf_fmt_restart_active(pfm_buffer_fmt_t *fmt, struct task_struct *task, pfm_ovfl_ctrl_t *ctrl, void *buf, struct pt_regs *regs)
+{
+ int ret = 0;
+ if (fmt->fmt_restart_active) ret = (*fmt->fmt_restart_active)(task, ctrl, buf, regs);
+ return ret;
+}
+
+
+
+int
+pfm_register_buffer_fmt(pfm_buffer_fmt_t *fmt)
+{
+ pfm_buffer_fmt_t *p;
+ int ret = 0;
+
+ /* some sanity checks */
+ if (fmt == NULL || fmt->fmt_name == NULL) return -EINVAL;
+
+ /* we need at least a handler */
+ if (fmt->fmt_handler == NULL) return -EINVAL;
+
+ /*
+ * XXX: need check validity of fmt_arg_size
+ */
+
+ LOCK_BUF_FMT_LIST();
+ p = pfm_buffer_fmt_list;
+
+
+ while (p) {
+ if (pfm_uuid_cmp(fmt->fmt_uuid, p->fmt_uuid) == 0) break;
+ p = p->fmt_next;
}
- psb = ctx->ctx_psb;
- down_write(&task->mm->mmap_sem);
+ if (p) {
+ printk(KERN_ERR "perfmon: duplicate sampling format: %s\n", fmt->fmt_name);
+ ret = -EBUSY;
+ } else {
+ fmt->fmt_prev = NULL;
+ fmt->fmt_next = pfm_buffer_fmt_list;
+ pfm_buffer_fmt_list = fmt;
+ printk(KERN_ERR "perfmon: added sampling format %s\n", fmt->fmt_name);
+ }
+ UNLOCK_BUF_FMT_LIST();
+
+ return ret;
+}
+
+int
+pfm_unregister_buffer_fmt(pfm_uuid_t uuid)
+{
+ pfm_buffer_fmt_t *p;
+ int ret = 0;
+
+ LOCK_BUF_FMT_LIST();
+ p = pfm_buffer_fmt_list;
+ while (p) {
+ if (memcmp(uuid, p->fmt_uuid, sizeof(pfm_uuid_t)) == 0) break;
+ p = p->fmt_next;
+ }
+ if (p) {
+ if (p->fmt_prev)
+ p->fmt_prev->fmt_next = p->fmt_next;
+ else
+ pfm_buffer_fmt_list = p->fmt_next;
+
+ if (p->fmt_next)
+ p->fmt_next->fmt_prev = p->fmt_prev;
+
+ printk(KERN_ERR "perfmon: removed sampling format: %s\n", p->fmt_name);
+ p->fmt_next = p->fmt_prev = NULL;
+ } else {
+ printk(KERN_ERR "perfmon: cannot unregister format, not found\n");
+ ret = -EINVAL;
+ }
+ UNLOCK_BUF_FMT_LIST();
+
+ return ret;
+
+}
+
+/*
+ * find a buffer format based on its uuid
+ */
+static pfm_buffer_fmt_t *
+pfm_find_buffer_fmt(pfm_uuid_t uuid, int nolock)
+{
+ pfm_buffer_fmt_t *p;
+
+ LOCK_BUF_FMT_LIST();
+ for (p = pfm_buffer_fmt_list; p ; p = p->fmt_next) {
+ if (pfm_uuid_cmp(uuid, p->fmt_uuid) == 0) break;
+ }
+
+ UNLOCK_BUF_FMT_LIST();
+
+ return p;
+}
+
+static int
+pfm_reserve_session(struct task_struct *task, int is_syswide, unsigned int cpu)
+{
+ /*
+ * validy checks on cpu_mask have been done upstream
+ */
+ LOCK_PFS();
+
+ DPRINT(("in sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n",
+ pfm_sessions.pfs_sys_sessions,
+ pfm_sessions.pfs_task_sessions,
+ pfm_sessions.pfs_sys_use_dbregs,
+ is_syswide,
+ cpu));
+
+ if (is_syswide) {
+ /*
+ * cannot mix system wide and per-task sessions
+ */
+ if (pfm_sessions.pfs_task_sessions > 0UL) {
+ DPRINT(("system wide not possible, %u conflicting task_sessions\n",
+ pfm_sessions.pfs_task_sessions));
+ goto abort;
+ }
+
+ if (pfm_sessions.pfs_sys_session[cpu]) goto error_conflict;
+
+ DPRINT(("reserving system wide session on CPU%u currently on CPU%u\n", cpu, smp_processor_id()));
+
+ pfm_sessions.pfs_sys_session[cpu] = task;
+
+ pfm_sessions.pfs_sys_sessions++ ;
+
+ } else {
+ if (pfm_sessions.pfs_sys_sessions) goto abort;
+ pfm_sessions.pfs_task_sessions++;
+ }
+
+ DPRINT(("out sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n",
+ pfm_sessions.pfs_sys_sessions,
+ pfm_sessions.pfs_task_sessions,
+ pfm_sessions.pfs_sys_use_dbregs,
+ is_syswide,
+ cpu));
+
+ UNLOCK_PFS();
+
+ return 0;
+
+error_conflict:
+ DPRINT(("system wide not possible, conflicting session [%d] on CPU%d\n",
+ pfm_sessions.pfs_sys_session[cpu]->pid,
+ smp_processor_id()));
+abort:
+ UNLOCK_PFS();
+
+ return -EBUSY;
+
+}
+
+static int
+pfm_unreserve_session(pfm_context_t *ctx, int is_syswide, unsigned int cpu)
+{
+
+ /*
+ * validy checks on cpu_mask have been done upstream
+ */
+ LOCK_PFS();
+
+ DPRINT(("in sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n",
+ pfm_sessions.pfs_sys_sessions,
+ pfm_sessions.pfs_task_sessions,
+ pfm_sessions.pfs_sys_use_dbregs,
+ is_syswide,
+ cpu));
+
+
+ if (is_syswide) {
+ pfm_sessions.pfs_sys_session[cpu] = NULL;
+ /*
+ * would not work with perfmon+more than one bit in cpu_mask
+ */
+ if (ctx && ctx->ctx_fl_using_dbreg) {
+ if (pfm_sessions.pfs_sys_use_dbregs == 0) {
+ printk(KERN_ERR "perfmon: invalid release for ctx %p sys_use_dbregs=0\n", ctx);
+ } else {
+ pfm_sessions.pfs_sys_use_dbregs--;
+ }
+ }
+ pfm_sessions.pfs_sys_sessions--;
+ } else {
+ pfm_sessions.pfs_task_sessions--;
+ }
+ DPRINT(("out sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n",
+ pfm_sessions.pfs_sys_sessions,
+ pfm_sessions.pfs_task_sessions,
+ pfm_sessions.pfs_sys_use_dbregs,
+ is_syswide,
+ cpu));
+
+ UNLOCK_PFS();
+
+ return 0;
+}
+
+/*
+ * removes virtual mapping of the sampling buffer.
+ * IMPORTANT: cannot be called with interrupts disable, e.g. inside
+ * a PROTECT_CTX() section.
+ */
+static int
+pfm_remove_smpl_mapping(struct task_struct *task, void *vaddr, unsigned long size)
+{
+ int r;
+
+ /* sanity checks */
+ if (task->mm == NULL || size == 0UL || vaddr == NULL) {
+ printk(KERN_ERR "perfmon: pfm_remove_smpl_mapping [%d] invalid context mm=%p\n", task->pid, task->mm);
+ return -EINVAL;
+ }
+
+ DPRINT(("smpl_vaddr=%p size=%lu\n", vaddr, size));
+
+ /*
+ * does the actual unmapping
+ */
+ down_write(&task->mm->mmap_sem);
+
+ DPRINT(("down_write done smpl_vaddr=%p size=%lu\n", vaddr, size));
+
+ r = do_munmap(task->mm, (unsigned long)vaddr, size);
+
+ up_write(&task->mm->mmap_sem);
+ if (r !=0) {
+ printk(KERN_ERR "perfmon: [%d] unable to unmap sampling buffer @%p size=%lu\n", task->pid, vaddr, size);
+ }
+
+ DPRINT(("do_unmap(%p, %lu)=%d\n", vaddr, size, r));
+
+ return 0;
+}
+
+/*
+ * free actual physical storage used by sampling buffer
+ */
+#if 0
+static int
+pfm_free_smpl_buffer(pfm_context_t *ctx)
+{
+ pfm_buffer_fmt_t *fmt;
+
+ if (ctx->ctx_smpl_hdr == NULL) goto invalid_free;
+
+ /*
+ * we won't use the buffer format anymore
+ */
+ fmt = ctx->ctx_buf_fmt;
+
+ DPRINT(("sampling buffer @%p size %lu vaddr=%p\n",
+ ctx->ctx_smpl_hdr,
+ ctx->ctx_smpl_size,
+ ctx->ctx_smpl_vaddr));
+
+ pfm_buf_fmt_exit(fmt, current, NULL, NULL);
+
+ /*
+ * free the buffer
+ */
+ pfm_rvfree(ctx->ctx_smpl_hdr, ctx->ctx_smpl_size);
+
+ ctx->ctx_smpl_hdr = NULL;
+ ctx->ctx_smpl_size = 0UL;
+
+ return 0;
+
+invalid_free:
+ printk(KERN_ERR "perfmon: pfm_free_smpl_buffer [%d] no buffer\n", current->pid);
+ return -EINVAL;
+}
+#endif
+
+static inline void
+pfm_exit_smpl_buffer(pfm_buffer_fmt_t *fmt)
+{
+ if (fmt == NULL) return;
+
+ pfm_buf_fmt_exit(fmt, current, NULL, NULL);
+
+}
+
+/*
+ * pfmfs should _never_ be mounted by userland - too much of security hassle,
+ * no real gain from having the whole whorehouse mounted. So we don't need
+ * any operations on the root directory. However, we need a non-trivial
+ * d_name - pfm: will go nicely and kill the special-casing in procfs.
+ */
+static struct vfsmount *pfmfs_mnt;
+#define PFMFS_MAGIC 0xa0b4d889
+
+#ifdef PFM_COMPILED_FOR_2_4
+
+static int
+pfmfs_statfs(struct super_block *sb, struct statfs *buf)
+{
+ buf->f_type = PFMFS_MAGIC;
+ buf->f_bsize = 1024;
+ buf->f_namelen = 255;
+ return 0;
+}
+
+static struct super_operations pfmfs_ops = {
+ statfs: pfmfs_statfs,
+};
+
+static struct super_block *
+pfmfs_read_super(struct super_block *sb, void *data, int silent)
+{
+ struct inode *root = new_inode(sb);
+ if (!root)
+ return NULL;
+ root->i_mode = S_IFDIR | S_IRUSR | S_IWUSR;
+ root->i_uid = root->i_gid = 0;
+ root->i_atime = root->i_mtime = root->i_ctime = CURRENT_TIME;
+ sb->s_blocksize = 1024;
+ sb->s_blocksize_bits = 10;
+ sb->s_magic = PFMFS_MAGIC;
+ sb->s_op = &pfmfs_ops;
+ sb->s_root = d_alloc(NULL, &(const struct qstr) { "pfm:", 4, 0 });
+ if (!sb->s_root) {
+ iput(root);
+ return NULL;
+ }
+ sb->s_root->d_sb = sb;
+ sb->s_root->d_parent = sb->s_root;
+ d_instantiate(sb->s_root, root);
+ return sb;
+}
+
+//static DECLARE_FSTYPE(pfm_fs_type, "pfmfs", pfmfs_read_super, FS_NOMOUNT);
+static struct file_system_type pfm_fs_type = {
+ name: "pfmfs",
+ read_super: pfmfs_read_super,
+ fs_flags: FS_NOMOUNT,
+};
+
+#else /* ! COMPILED_FOR_2_4 */
+
+static struct super_block *
+pfmfs_get_sb(struct file_system_type *fs_type, int flags, char *dev_name, void *data)
+{
+ return get_sb_pseudo(fs_type, "pfm:", NULL, PFMFS_MAGIC);
+}
+
+static struct file_system_type pfm_fs_type = {
+ .name = "pfmfs",
+ .get_sb = pfmfs_get_sb,
+ .kill_sb = kill_anon_super,
+};
+#endif /* COMPILED_FOR_2_4 */
+
+static int __init
+init_pfm_fs(void)
+{
+ int err = register_filesystem(&pfm_fs_type);
+ if (!err) {
+ pfmfs_mnt = kern_mount(&pfm_fs_type);
+ err = PTR_ERR(pfmfs_mnt);
+ if (IS_ERR(pfmfs_mnt))
+ unregister_filesystem(&pfm_fs_type);
+ else
+ err = 0;
+ }
+ return err;
+}
+
+static void __exit
+exit_pfm_fs(void)
+{
+ unregister_filesystem(&pfm_fs_type);
+ mntput(pfmfs_mnt);
+}
+
+static loff_t
+pfm_lseek(struct file *file, loff_t offset, int whence)
+{
+ DPRINT(("pfm_lseek called\n"));
+ return -ESPIPE;
+}
+
+static ssize_t
+pfm_do_read(struct file *filp, char *buf, size_t size, loff_t *ppos)
+{
+ pfm_context_t *ctx;
+ pfm_msg_t *msg;
+ ssize_t ret;
+ unsigned long flags;
+ DECLARE_WAITQUEUE(wait, current);
+ if (PFM_IS_FILE(filp) == 0) {
+ printk(KERN_ERR "perfmon: pfm_poll: bad magic [%d]\n", current->pid);
+ return -EINVAL;
+ }
+
+ ctx = (pfm_context_t *)filp->private_data;
+ if (ctx == NULL) {
+ printk(KERN_ERR "perfmon: pfm_read: NULL ctx [%d]\n", current->pid);
+ return -EINVAL;
+ }
+
+ /*
+ * check even when there is no message
+ */
+ if (size < sizeof(pfm_msg_t)) {
+ DPRINT(("message is too small ctx=%p (>=%ld)\n", ctx, sizeof(pfm_msg_t)));
+ return -EINVAL;
+ }
+ /*
+ * seeks are not allowed on message queues
+ */
+ if (ppos != &filp->f_pos) return -ESPIPE;
+
+ PROTECT_CTX(ctx, flags);
+
+ /*
+ * put ourselves on the wait queue
+ */
+ add_wait_queue(&ctx->ctx_msgq_wait, &wait);
+
+
+ for(;;) {
+ /*
+ * check wait queue
+ */
+
+ set_current_state(TASK_INTERRUPTIBLE);
+
+ DPRINT(("head=%d tail=%d\n", ctx->ctx_msgq_head, ctx->ctx_msgq_tail));
+
+ ret = 0;
+ if(PFM_CTXQ_EMPTY(ctx) == 0) break;
+
+ UNPROTECT_CTX(ctx, flags);
+
+ /*
+ * check non-blocking read
+ */
+ ret = -EAGAIN;
+ if(filp->f_flags & O_NONBLOCK) break;
+
+ /*
+ * check pending signals
+ */
+ if(signal_pending(current)) {
+ ret = -EINTR;
+ break;
+ }
+ /*
+ * no message, so wait
+ */
+ schedule();
+
+ PROTECT_CTX(ctx, flags);
+ }
+ DPRINT(("[%d] back to running ret=%ld\n", current->pid, ret));
+ set_current_state(TASK_RUNNING);
+ remove_wait_queue(&ctx->ctx_msgq_wait, &wait);
+
+ if (ret < 0) goto abort;
+
+ ret = -EINVAL;
+ msg = pfm_get_next_msg(ctx);
+ if (msg == NULL) {
+ printk(KERN_ERR "perfmon: pfm_read no msg for ctx=%p [%d]\n", ctx, current->pid);
+ goto abort_locked;
+ }
+
+ DPRINT(("[%d] fd=%d type=%d\n", current->pid, msg->pfm_gen_msg.msg_ctx_fd, msg->pfm_gen_msg.msg_type));
+
+ ret = -EFAULT;
+ if(copy_to_user(buf, msg, sizeof(pfm_msg_t)) == 0) ret = sizeof(pfm_msg_t);
+
+abort_locked:
+ UNPROTECT_CTX(ctx, flags);
+abort:
+ return ret;
+}
+
+static ssize_t
+pfm_read(struct file *filp, char *buf, size_t size, loff_t *ppos)
+{
+ int oldvar, ret;
+
+ oldvar = pfm_debug_var;
+ pfm_debug_var = pfm_sysctl.debug_pfm_read;
+ ret = pfm_do_read(filp, buf, size, ppos);
+ pfm_debug_var = oldvar;
+ return ret;
+}
+
+static ssize_t
+pfm_write(struct file *file, const char *ubuf,
+ size_t size, loff_t *ppos)
+{
+ DPRINT(("pfm_write called\n"));
+ return -EINVAL;
+}
+
+static unsigned int
+pfm_poll(struct file *filp, poll_table * wait)
+{
+ pfm_context_t *ctx;
+ unsigned long flags;
+ unsigned int mask = 0;
+
+ if (PFM_IS_FILE(filp) == 0) {
+ printk(KERN_ERR "perfmon: pfm_poll: bad magic [%d]\n", current->pid);
+ return 0;
+ }
+
+ ctx = (pfm_context_t *)filp->private_data;
+ if (ctx == NULL) {
+ printk(KERN_ERR "perfmon: pfm_poll: NULL ctx [%d]\n", current->pid);
+ return 0;
+ }
+
+
+ DPRINT(("pfm_poll ctx_fd=%d before poll_wait\n", ctx->ctx_fd));
+
+ poll_wait(filp, &ctx->ctx_msgq_wait, wait);
- r = do_munmap(task->mm, ctx->ctx_smpl_vaddr, psb->psb_size);
+ PROTECT_CTX(ctx, flags);
- up_write(&task->mm->mmap_sem);
- if (r !=0) {
- printk(KERN_DEBUG "perfmon: pid %d unable to unmap sampling buffer "
- "@0x%lx size=%ld\n", task->pid, ctx->ctx_smpl_vaddr, psb->psb_size);
- }
+ if (PFM_CTXQ_EMPTY(ctx) == 0)
+ mask = POLLIN | POLLRDNORM;
- DBprintk(("[%d] do_unmap(0x%lx, %ld)=%d refcnt=%lu psb_flags=0x%x\n",
- task->pid, ctx->ctx_smpl_vaddr, psb->psb_size, r, psb->psb_refcnt, psb->psb_flags));
+ UNPROTECT_CTX(ctx, flags);
- return 0;
+ DPRINT(("pfm_poll ctx_fd=%d mask=0x%x\n", ctx->ctx_fd, mask));
+
+ return mask;
}
-static pfm_context_t *
-pfm_context_alloc(void)
+static int
+pfm_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
+{
+ DPRINT(("pfm_ioctl called\n"));
+ return -EINVAL;
+}
+
+/*
+ * context is locked when coming here
+ */
+static inline int
+pfm_do_fasync(int fd, struct file *filp, pfm_context_t *ctx, int on)
+{
+ int ret;
+
+ ret = fasync_helper (fd, filp, on, &ctx->ctx_async_queue);
+
+ DPRINT(("pfm_fasync called by [%d] on ctx_fd=%d on=%d async_queue=%p ret=%d\n",
+ current->pid,
+ fd,
+ on,
+ ctx->ctx_async_queue, ret));
+
+ return ret;
+}
+
+static int
+pfm_fasync(int fd, struct file *filp, int on)
{
pfm_context_t *ctx;
+ unsigned long flags;
+ int ret;
- /* allocate context descriptor */
- ctx = kmalloc(sizeof(pfm_context_t), GFP_KERNEL);
- if (ctx) memset(ctx, 0, sizeof(pfm_context_t));
-
- return ctx;
+ if (PFM_IS_FILE(filp) == 0) {
+ printk(KERN_ERR "perfmon: pfm_fasync bad magic [%d]\n", current->pid);
+ return -EBADF;
+ }
+
+ ctx = (pfm_context_t *)filp->private_data;
+ if (ctx == NULL) {
+ printk(KERN_ERR "perfmon: pfm_fasync NULL ctx [%d]\n", current->pid);
+ return -EBADF;
+ }
+
+
+ PROTECT_CTX(ctx, flags);
+
+ ret = pfm_do_fasync(fd, filp, ctx, on);
+
+ DPRINT(("pfm_fasync called by [%d] on ctx_fd=%d on=%d async_queue=%p ret=%d\n",
+ current->pid,
+ fd,
+ on,
+ ctx->ctx_async_queue, ret));
+
+ UNPROTECT_CTX(ctx, flags);
+
+ return ret;
}
+#ifdef CONFIG_SMP
+/*
+ * this function is exclusively called from pfm_close().
+ * The context is not protected at that time, nor are interrupts
+ * on the remote CPU. That's necessary to avoid deadlocks.
+ */
static void
-pfm_context_free(pfm_context_t *ctx)
+pfm_syswide_force_stop(void *info)
+{
+ pfm_context_t *ctx = (pfm_context_t *)info;
+ struct pt_regs *regs = ia64_task_regs(current);
+ struct task_struct *owner;
+
+ if (ctx->ctx_cpu != smp_processor_id()) {
+ printk(KERN_ERR "perfmon: pfm_syswide_force_stop for CPU%d but on CPU%d\n",
+ ctx->ctx_cpu,
+ smp_processor_id());
+ return;
+ }
+ owner = GET_PMU_OWNER();
+ if (owner != ctx->ctx_task) {
+ printk(KERN_ERR "perfmon: pfm_syswide_force_stop CPU%d unexpected owner [%d] instead of [%d]\n",
+ smp_processor_id(),
+ owner->pid, ctx->ctx_task->pid);
+ return;
+ }
+ if (GET_PMU_CTX() != ctx) {
+ printk(KERN_ERR "perfmon: pfm_syswide_force_stop CPU%d unexpected ctx %p instead of %p\n",
+ smp_processor_id(),
+ GET_PMU_CTX(), ctx);
+ return;
+ }
+
+ DPRINT(("[%d] on CPU%d forcing system wide stop for [%d]\n", current->pid, smp_processor_id(), ctx->ctx_task->pid));
+ /*
+ * Update local PMU
+ */
+ ia64_set_dcr(ia64_get_dcr() & ~IA64_DCR_PP);
+ ia64_srlz_i();
+ /*
+ * update local cpuinfo
+ */
+ PFM_CPUINFO_CLEAR(PFM_CPUINFO_DCR_PP);
+ PFM_CPUINFO_CLEAR(PFM_CPUINFO_SYST_WIDE);
+ PFM_CPUINFO_CLEAR(PFM_CPUINFO_EXCL_IDLE);
+
+ pfm_clear_psr_pp();
+
+ /*
+ * also stop monitoring in the local interrupted task
+ */
+ ia64_psr(regs)->pp = 0;
+
+ SET_PMU_OWNER(NULL, NULL);
+}
+
+static void
+pfm_syswide_cleanup_other_cpu(pfm_context_t *ctx)
{
- if (ctx) kfree(ctx);
+ int ret;
+
+ DPRINT(("[%d] calling CPU%d for cleanup\n", current->pid, ctx->ctx_cpu));
+ ret = smp_call_function_single(ctx->ctx_cpu, pfm_syswide_force_stop, ctx, 0, 1);
+ DPRINT(("[%d] called CPU%d for cleanup ret=%d\n", current->pid, ctx->ctx_cpu, ret));
}
+#endif /* CONFIG_SMP */
+/*
+ * called either on explicit close() or from exit_files().
+ *
+ * IMPORTANT: we get called ONLY when the refcnt on the file gets to zero (fput()),i.e,
+ * last task to access the file. Nobody else can access the file at this point.
+ *
+ * When called from exit_files(), the VMA has been freed because exit_mm()
+ * is executed before exit_files().
+ *
+ * When called from exit_files(), the current task is not yet ZOMBIE but we will
+ * flush the PMU state to the context. This means * that when we see the context
+ * state as TERMINATED we are guranteed to have the latest PMU state available,
+ * even if the task itself is in the middle of being ctxsw out.
+ */
+static int pfm_context_unload(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs);
static int
-pfm_remap_buffer(struct vm_area_struct *vma, unsigned long buf, unsigned long addr, unsigned long size)
+pfm_close(struct inode *inode, struct file *filp)
{
- unsigned long page;
+ pfm_context_t *ctx;
+ struct task_struct *task;
+ struct pt_regs *regs;
+ DECLARE_WAITQUEUE(wait, current);
+ unsigned long flags;
+ unsigned long smpl_buf_size = 0UL;
+ void *smpl_buf_vaddr = NULL;
+ void *smpl_buf_addr = NULL;
+ int free_possible = 1;
+
+ { u64 psr = pfm_get_psr();
+ BUG_ON((psr & IA64_PSR_I) == 0UL);
+ }
- DBprintk(("CPU%d buf=0x%lx addr=0x%lx size=%ld\n", smp_processor_id(), buf, addr, size));
+ DPRINT(("pfm_close called private=%p\n", filp->private_data));
- while (size > 0) {
- page = pfm_kvirt_to_pa(buf);
+ if (!inode) {
+ printk(KERN_ERR "pfm_close: NULL inode\n");
+ return 0;
+ }
- if (remap_page_range(vma, addr, page, PAGE_SIZE, PAGE_READONLY)) return -ENOMEM;
+ if (PFM_IS_FILE(filp) == 0) {
+ printk(KERN_ERR "perfmon: pfm_close: bad magic [%d]\n", current->pid);
+ return -EBADF;
+ }
- addr += PAGE_SIZE;
- buf += PAGE_SIZE;
- size -= PAGE_SIZE;
+ ctx = (pfm_context_t *)filp->private_data;
+ if (ctx == NULL) {
+ printk(KERN_ERR "perfmon: pfm_close: NULL ctx [%d]\n", current->pid);
+ return -EBADF;
+ }
+
+ PROTECT_CTX(ctx, flags);
+
+ /*
+ * remove our file from the async queue, if we use it
+ */
+ if (filp->f_flags & FASYNC) {
+ DPRINT(("[%d] before async_queue=%p\n", current->pid, ctx->ctx_async_queue));
+ pfm_do_fasync (-1, filp, ctx, 0);
+ DPRINT(("[%d] after async_queue=%p\n", current->pid, ctx->ctx_async_queue));
+ }
+
+ task = PFM_CTX_TASK(ctx);
+
+ DPRINT(("[%d] ctx_state=%d\n", current->pid, ctx->ctx_state));
+
+ if (CTX_IS_UNLOADED(ctx) || CTX_IS_TERMINATED(ctx)) {
+ goto doit;
+ }
+
+ regs = ia64_task_regs(task);
+
+ /*
+ * context still loaded/masked and self monitoring,
+ * we stop/unload and we destroy right here
+ *
+ * We always go here for system-wide sessions
+ */
+ if (task == current) {
+#ifdef CONFIG_SMP
+ /*
+ * the task IS the owner but it migrated to another CPU: that's bad
+ * but we must handle this cleanly. Unfortunately, the kernel does
+ * not provide a mechanism to block migration (while the context is loaded).
+ *
+ * We need to release the resource on the ORIGINAL cpu.
+ */
+ if (ctx->ctx_fl_system && ctx->ctx_cpu != smp_processor_id()) {
+
+ DPRINT(("[%d] should be running on CPU%d\n", current->pid, ctx->ctx_cpu));
+
+ UNPROTECT_CTX(ctx, flags);
+
+ pfm_syswide_cleanup_other_cpu(ctx);
+
+ PROTECT_CTX(ctx, flags);
+
+ /*
+ * short circuit pfm_context_unload();
+ */
+ task->thread.pfm_context = NULL;
+ ctx->ctx_task = NULL;
+
+ CTX_UNLOADED(ctx);
+
+ pfm_unreserve_session(ctx, 1 , ctx->ctx_cpu);
+ } else
+#endif /* CONFIG_SMP */
+ {
+
+ DPRINT(("forcing unload on [%d]\n", current->pid));
+ /*
+ * stop and unload, returning with state UNLOADED
+ * and session unreserved.
+ */
+ pfm_context_unload(ctx, NULL, 0, regs);
+
+ CTX_TERMINATED(ctx);
+
+ DPRINT(("[%d] ctx_state=%d\n", current->pid, ctx->ctx_state));
+ }
+ goto doit;
+ }
+
+ /*
+ * The task is currently blocked or will block after an overflow.
+ * we must force it to wakeup to get out of the
+ * MASKED state and transition to the unloaded state by itself
+ */
+ if (CTX_IS_MASKED(ctx) && CTX_OVFL_NOBLOCK(ctx) == 0) {
+
+ /*
+ * set a "partial" zombie state to be checked
+ * upon return from down() in pfm_handle_work().
+ *
+ * We cannot use the ZOMBIE state, because it is checked
+ * by pfm_load_regs() which is called upon wakeup from down().
+ * In such cas, it would free the context and then we would
+ * return to pfm_handle_work() which would access the
+ * stale context. Instead, we set a flag invisible to pfm_load_regs()
+ * but visible to pfm_handle_work().
+ *
+ * For some window of time, we have a zombie context with
+ * ctx_state = MASKED and not ZOMBIE
+ */
+ ctx->ctx_fl_going_zombie = 1;
+
+ /*
+ * force task to wake up from MASKED state
+ */
+ up(&ctx->ctx_restart_sem);
+
+ DPRINT(("waking up ctx_state=%d for [%d]\n", ctx->ctx_state, current->pid));
+
+ /*
+ * put ourself to sleep waiting for the other
+ * task to report completion
+ *
+ * the context is protected by mutex, therefore there
+ * is no risk of being notified of completion before
+ * begin actually on the waitq.
+ */
+ set_current_state(TASK_INTERRUPTIBLE);
+ add_wait_queue(&ctx->ctx_zombieq, &wait);
+
+ UNPROTECT_CTX(ctx, flags);
+
+ /*
+ * XXX: check for signals :
+ * - ok of explicit close
+ * - not ok when coming from exit_files()
+ */
+ schedule();
+
+ DPRINT(("woken up ctx_state=%d for [%d]\n", ctx->ctx_state, current->pid));
+
+ PROTECT_CTX(ctx, flags);
+
+ remove_wait_queue(&ctx->ctx_zombieq, &wait);
+ set_current_state(TASK_RUNNING);
+
+ /*
+ * context is terminated at this point
+ */
+ DPRINT(("after zombie wakeup ctx_state=%d for [%d]\n", ctx->ctx_state, current->pid));
+ }
+ else {
+#ifdef CONFIG_SMP
+ /*
+ * switch context to zombie state
+ */
+ CTX_ZOMBIE(ctx);
+
+ DPRINT(("zombie ctx for [%d]\n", task->pid));
+ /*
+ * cannot free the context on the spot. deferred until
+ * the task notices the ZOMBIE state
+ */
+ free_possible = 0;
+#else
+ pfm_context_unload(ctx, NULL, 0, regs);
+#endif
+ }
+
+doit: /* cannot assume task is defined from now on */
+ /*
+ * the context is still attached to a task (possibly current)
+ * we cannot destroy it right now
+ */
+ /*
+ * remove virtual mapping, if any. will be NULL when
+ * called from exit_files().
+ */
+ if (ctx->ctx_smpl_vaddr) {
+ smpl_buf_vaddr = ctx->ctx_smpl_vaddr;
+ smpl_buf_size = ctx->ctx_smpl_size;
+ ctx->ctx_smpl_vaddr = NULL;
+ }
+
+ /*
+ * we must fre the sampling buffer right here because
+ * we cannot rely on it being cleaned up later by the
+ * monitored task. It is not possible to free vmalloc'ed
+ * memory in pfm_load_regs(). Instead, we remove the buffer
+ * now. should there be subsequent PMU overflow originally
+ * meant for sampling, the will be converted to spurious
+ * and that's fine because the monitoring tools is gone anyway.
+ */
+ if (ctx->ctx_smpl_hdr) {
+ smpl_buf_addr = ctx->ctx_smpl_hdr;
+ smpl_buf_size = ctx->ctx_smpl_size;
+ /* no more sampling */
+ ctx->ctx_smpl_hdr = NULL;
}
+
+
+ DPRINT(("[%d] ctx_state=%d free_possible=%d vaddr=%p addr=%p size=%lu\n",
+ current->pid,
+ ctx->ctx_state,
+ free_possible,
+ smpl_buf_vaddr,
+ smpl_buf_addr,
+ smpl_buf_size));
+
+ if (smpl_buf_addr) pfm_exit_smpl_buffer(ctx->ctx_buf_fmt);
+
+ /*
+ * UNLOADED and TERMINATED mean that the session has already been
+ * unreserved.
+ */
+ if (CTX_IS_ZOMBIE(ctx)) {
+ pfm_unreserve_session(ctx, ctx->ctx_fl_system , ctx->ctx_cpu);
+ }
+
+ /*
+ * disconnect file descriptor from context must be done
+ * before we unlock.
+ */
+ filp->private_data = NULL;
+
+ /*
+ * if we free on the spot, the context is now completely unreacheable
+ * from the callers side. The monitored task side is also cut, so we
+ * can freely cut.
+ *
+ * If we have a deferred free, only the caller side is disconnected.
+ */
+ UNPROTECT_CTX(ctx, flags);
+
+ /*
+ * if there was a mapping, then we systematically remove it
+ * at this point. Cannot be done inside critical section
+ * because some VM function reenables interrupts.
+ *
+ * All memory free operations (especially for vmalloc'ed memory)
+ * MUST be done with interrupts ENABLED.
+ */
+ if (smpl_buf_vaddr) pfm_remove_smpl_mapping(current, smpl_buf_vaddr, smpl_buf_size);
+ if (smpl_buf_addr) pfm_rvfree(smpl_buf_addr, smpl_buf_size);
+
+ /*
+ * return the memory used by the context
+ */
+ if (free_possible) pfm_context_free(ctx);
+
return 0;
}
+static int
+pfm_no_open(struct inode *irrelevant, struct file *dontcare)
+{
+ DPRINT(("pfm_no_open called\n"));
+ return -ENXIO;
+}
+
+static struct file_operations pfm_file_ops = {
+ .llseek = pfm_lseek,
+ .read = pfm_read,
+ .write = pfm_write,
+ .poll = pfm_poll,
+ .ioctl = pfm_ioctl,
+ .open = pfm_no_open, /* special open code to disallow open via /proc */
+ .fasync = pfm_fasync,
+ .release = pfm_close
+};
+
+static int
+pfmfs_delete_dentry(struct dentry *dentry)
+{
+ return 1;
+}
+static struct dentry_operations pfmfs_dentry_operations = {
+ d_delete: pfmfs_delete_dentry,
+};
+
+
+static int
+pfm_alloc_fd(struct file **cfile)
+{
+ int fd, ret = 0;
+ struct file *file = NULL;
+ struct inode * inode;
+ char name[32];
+ struct qstr this;
+
+ fd = get_unused_fd();
+ if (fd < 0) return -ENFILE;
+
+ ret = -ENFILE;
+
+ file = get_empty_filp();
+ if (!file) goto out;
+
+ /*
+ * allocate a new inode
+ */
+ inode = new_inode(pfmfs_mnt->mnt_sb);
+ if (!inode) goto out;
+
+ DPRINT(("new inode ino=%ld @%p\n", inode->i_ino, inode));
+
+ inode->i_sb = pfmfs_mnt->mnt_sb;
+ inode->i_mode = S_IFCHR|S_IRUGO;
+ inode->i_sock = 0;
+ inode->i_uid = current->fsuid;
+ inode->i_gid = current->fsgid;
+
+ sprintf(name, "[%lu]", inode->i_ino);
+ this.name = name;
+ this.len = strlen(name);
+ this.hash = inode->i_ino;
+
+ ret = -ENOMEM;
+
+ /*
+ * allocate a new dcache entry
+ */
+ file->f_dentry = d_alloc(pfmfs_mnt->mnt_sb->s_root, &this);
+ if (!file->f_dentry) goto out;
+
+ file->f_dentry->d_op = &pfmfs_dentry_operations;
+
+ d_add(file->f_dentry, inode);
+ file->f_vfsmnt = mntget(pfmfs_mnt);
+
+ file->f_op = &pfm_file_ops;
+ file->f_mode = FMODE_READ;
+ file->f_flags = O_RDONLY;
+ file->f_pos = 0;
+
+ /*
+ * may have to delay until context is attached?
+ */
+ fd_install(fd, file);
+
+ /*
+ * the file structure we will use
+ */
+ *cfile = file;
+
+ return fd;
+out:
+ if (file) put_filp(file);
+ put_unused_fd(fd);
+ return ret;
+}
+
+static void
+pfm_free_fd(int fd, struct file *file)
+{
+ if (file) put_filp(file);
+ put_unused_fd(fd);
+}
+
/*
- * counts the number of PMDS to save per entry.
- * This code is generic enough to accommodate more than 64 PMDS when they become available
+ * This function gets called from mm/mmap.c:exit_mmap() only when there is a sampling buffer
+ * attached to the context AND the current task has a mapping for it, i.e., it is the original
+ * creator of the context.
+ *
+ * This function is used to remember the fact that the vma describing the sampling buffer
+ * has now been removed. It can only be called when no other tasks share the same mm context.
+ *
*/
-static unsigned long
-pfm_smpl_entry_size(unsigned long *which, unsigned long size)
+static void
+pfm_vm_close(struct vm_area_struct *vma)
+{
+ pfm_context_t *ctx = (pfm_context_t *)vma->vm_private_data;
+ unsigned long flags;
+
+ PROTECT_CTX(ctx, flags);
+ ctx->ctx_smpl_vaddr = NULL;
+ UNPROTECT_CTX(ctx, flags);
+ DPRINT(("[%d] clearing vaddr for ctx %p\n", current->pid, ctx));
+}
+
+static int
+pfm_remap_buffer(struct vm_area_struct *vma, unsigned long buf, unsigned long addr, unsigned long size)
{
- unsigned long i, res = 0;
+ unsigned long page;
+
+ DPRINT(("CPU%d buf=0x%lx addr=0x%lx size=%ld\n", smp_processor_id(), buf, addr, size));
- for (i=0; i < size; i++, which++) res += hweight64(*which);
+ while (size > 0) {
+ page = pfm_kvirt_to_pa(buf);
- DBprintk(("weight=%ld\n", res));
+ if (pfm_remap_page_range(vma, addr, page, PAGE_SIZE, PAGE_READONLY)) return -ENOMEM;
- return res;
+ addr += PAGE_SIZE;
+ buf += PAGE_SIZE;
+ size -= PAGE_SIZE;
+ }
+ return 0;
}
/*
- * Allocates the sampling buffer and remaps it into caller's address space
+ * allocate a sampling buffer and remaps it into the user address space of the task
*/
static int
-pfm_smpl_buffer_alloc(pfm_context_t *ctx, unsigned long *which_pmds, unsigned long entries,
- void **user_vaddr)
+pfm_smpl_buffer_alloc(struct task_struct *task, pfm_context_t *ctx, unsigned long rsize, void **user_vaddr)
{
- struct mm_struct *mm = current->mm;
+ struct mm_struct *mm = task->mm;
struct vm_area_struct *vma = NULL;
- unsigned long size, regcount;
+ unsigned long size;
void *smpl_buf;
- pfm_smpl_buffer_desc_t *psb;
-
- /* note that regcount might be 0, in this case only the header for each
- * entry will be recorded.
- */
- regcount = pfm_smpl_entry_size(which_pmds, 1);
-
- if ((sizeof(perfmon_smpl_hdr_t)+ entries*sizeof(perfmon_smpl_entry_t)) <= entries) {
- DBprintk(("requested entries %lu is too big\n", entries));
- return -EINVAL;
- }
/*
- * 1 buffer hdr and for each entry a header + regcount PMDs to save
+ * the fixed header + requested size and align to page boundary
*/
- size = PAGE_ALIGN( sizeof(perfmon_smpl_hdr_t)
- + entries * (sizeof(perfmon_smpl_entry_t) + regcount*sizeof(u64)));
+ size = PAGE_ALIGN(rsize);
- DBprintk(("sampling buffer size=%lu bytes\n", size));
+ DPRINT(("sampling buffer rsize=%lu size=%lu bytes\n", rsize, size));
/*
* check requested size to avoid Denial-of-service attacks
- * XXX: may have to refine this test
+ * XXX: may have to refine this test
* Check against address space limit.
*
- * if ((mm->total_vm << PAGE_SHIFT) + len> current->rlim[RLIMIT_AS].rlim_cur)
+ * if ((mm->total_vm << PAGE_SHIFT) + len> task->rlim[RLIMIT_AS].rlim_cur)
* return -ENOMEM;
*/
- if (size > current->rlim[RLIMIT_MEMLOCK].rlim_cur) return -EAGAIN;
+ if (size > task->rlim[RLIMIT_MEMLOCK].rlim_cur) return -EAGAIN;
/*
* We do the easy to undo allocations first.
*/
smpl_buf = pfm_rvmalloc(size);
if (smpl_buf == NULL) {
- DBprintk(("Can't allocate sampling buffer\n"));
+ DPRINT(("Can't allocate sampling buffer\n"));
return -ENOMEM;
}
- DBprintk(("smpl_buf @%p\n", smpl_buf));
-
- /* allocate sampling buffer descriptor now */
- psb = kmalloc(sizeof(*psb), GFP_KERNEL);
- if (psb == NULL) {
- DBprintk(("Can't allocate sampling buffer descriptor\n"));
- goto error_kmalloc;
- }
+ DPRINT(("[%d] smpl_buf @%p\n", current->pid, smpl_buf));
/* allocate vma */
vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
if (!vma) {
- DBprintk(("Cannot allocate vma\n"));
+ DPRINT(("Cannot allocate vma\n"));
goto error_kmem;
}
/*
* partially initialize the vma for the sampling buffer
*
* The VM_DONTCOPY flag is very important as it ensures that the mapping
- * will never be inherited for any child process (via fork()) which is always
+ * will never be inherited for any child process (via fork()) which is always
* what we want.
*/
vma->vm_mm = mm;
vma->vm_flags = VM_READ| VM_MAYREAD |VM_RESERVED|VM_DONTCOPY;
vma->vm_page_prot = PAGE_READONLY; /* XXX may need to change */
- vma->vm_ops = &pfm_vm_ops; /* necesarry to get the close() callback */
+ vma->vm_ops = &pfm_vm_ops;
vma->vm_pgoff = 0;
vma->vm_file = NULL;
- vma->vm_private_data = psb; /* information needed by the pfm_vm_close() function */
+ vma->vm_private_data = ctx; /* information needed by the pfm_vm_close() function */
/*
* Now we have everything we need and we can initialize
* and connect all the data structures
*/
- psb->psb_hdr = smpl_buf;
- psb->psb_addr = ((char *)smpl_buf)+sizeof(perfmon_smpl_hdr_t); /* first entry */
- psb->psb_size = size; /* aligned size */
- psb->psb_index = 0;
- psb->psb_entries = entries;
- psb->psb_refcnt = 1;
- psb->psb_flags = PSB_HAS_VMA;
-
- spin_lock_init(&psb->psb_lock);
-
- /*
- * XXX: will need to do cacheline alignment to avoid false sharing in SMP mode and
- * multitask monitoring.
- */
- psb->psb_entry_size = sizeof(perfmon_smpl_entry_t) + regcount*sizeof(u64);
-
- DBprintk(("psb @%p entry_size=%ld hdr=%p addr=%p refcnt=%lu psb_flags=0x%x\n",
- (void *)psb,psb->psb_entry_size, (void *)psb->psb_hdr,
- (void *)psb->psb_addr, psb->psb_refcnt, psb->psb_flags));
-
- /* initialize some of the fields of user visible buffer header */
- psb->psb_hdr->hdr_version = PFM_SMPL_VERSION;
- psb->psb_hdr->hdr_entry_size = psb->psb_entry_size;
- psb->psb_hdr->hdr_pmds[0] = which_pmds[0];
+ ctx->ctx_smpl_hdr = smpl_buf;
+ ctx->ctx_smpl_size = size; /* aligned size */
/*
* Let's do the difficult operations next.
* now we atomically find some area in the address space and
* remap the buffer in it.
*/
- down_write(¤t->mm->mmap_sem);
-
+ down_write(&task->mm->mmap_sem);
/* find some free area in address space, must have mmap sem held */
vma->vm_start = get_unmapped_area(NULL, 0, size, 0, MAP_PRIVATE|MAP_ANONYMOUS);
if (vma->vm_start == 0UL) {
- DBprintk(("Cannot find unmapped area for size %ld\n", size));
- up_write(¤t->mm->mmap_sem);
+ DPRINT(("Cannot find unmapped area for size %ld\n", size));
+ up_write(&task->mm->mmap_sem);
goto error;
}
vma->vm_end = vma->vm_start + size;
- DBprintk(("entries=%ld aligned size=%ld, unmapped @0x%lx\n", entries, size, vma->vm_start));
+ DPRINT(("aligned size=%ld, hdr=%p mapped @0x%lx\n", size, ctx->ctx_smpl_hdr, vma->vm_start));
- /* can only be applied to current, need to have the mm semaphore held when called */
+ /* can only be applied to current task, need to have the mm semaphore held when called */
if (pfm_remap_buffer(vma, (unsigned long)smpl_buf, vma->vm_start, size)) {
- DBprintk(("Can't remap buffer\n"));
- up_write(¤t->mm->mmap_sem);
+ DPRINT(("Can't remap buffer\n"));
+ up_write(&task->mm->mmap_sem);
goto error;
}
mm->total_vm += size >> PAGE_SHIFT;
- up_write(¤t->mm->mmap_sem);
-
- /* store which PMDS to record */
- ctx->ctx_smpl_regs[0] = which_pmds[0];
-
-
- /* link to perfmon context */
- ctx->ctx_psb = psb;
+ up_write(&task->mm->mmap_sem);
/*
- * keep track of user level virtual address
+ * keep track of user level virtual address
*/
- ctx->ctx_smpl_vaddr = *(unsigned long *)user_vaddr = vma->vm_start;
+ ctx->ctx_smpl_vaddr = (void *)vma->vm_start;
+ *(unsigned long *)user_vaddr = vma->vm_start;
return 0;
error:
kmem_cache_free(vm_area_cachep, vma);
error_kmem:
- kfree(psb);
-error_kmalloc:
pfm_rvfree(smpl_buf, size);
+
return -ENOMEM;
}
+/*
+ * XXX: do something better here
+ */
static int
-pfm_reserve_session(struct task_struct *task, int is_syswide, unsigned long cpu_mask)
+pfm_bad_permissions(struct task_struct *task)
{
- unsigned long m, undo_mask;
- unsigned int n, i;
-
- /*
- * validy checks on cpu_mask have been done upstream
- */
- LOCK_PFS();
-
- if (is_syswide) {
- /*
- * cannot mix system wide and per-task sessions
- */
- if (pfm_sessions.pfs_task_sessions > 0UL) {
- DBprintk(("system wide not possible, %u conflicting task_sessions\n",
- pfm_sessions.pfs_task_sessions));
- goto abort;
- }
+ /* stolen from bad_signal() */
+ return (current->session != task->session)
+ && (current->euid ^ task->suid) && (current->euid ^ task->uid)
+ && (current->uid ^ task->suid) && (current->uid ^ task->uid);
+}
- m = cpu_mask; undo_mask = 0UL; n = 0;
- DBprintk(("cpu_mask=0x%lx\n", cpu_mask));
- for(i=0; m; i++, m>>=1) {
+static int
+pfarg_is_sane(struct task_struct *task, pfarg_context_t *pfx)
+{
+ int ctx_flags;
- if ((m & 0x1) == 0UL) continue;
+ /* valid signal */
- if (pfm_sessions.pfs_sys_session[i]) goto undo;
+ ctx_flags = pfx->ctx_flags;
- DBprintk(("reserving CPU%d currently on CPU%d\n", i, smp_processor_id()));
+ if (ctx_flags & PFM_FL_SYSTEM_WIDE) {
- pfm_sessions.pfs_sys_session[i] = task;
- undo_mask |= 1UL << i;
- n++;
+ /*
+ * cannot block in this mode
+ */
+ if (ctx_flags & PFM_FL_NOTIFY_BLOCK) {
+ DPRINT(("cannot use blocking mode when in system wide monitoring\n"));
+ return -EINVAL;
}
- pfm_sessions.pfs_sys_sessions += n;
} else {
- if (pfm_sessions.pfs_sys_sessions) goto abort;
- pfm_sessions.pfs_task_sessions++;
- }
- DBprintk(("task_sessions=%u sys_session[%d]=%d",
- pfm_sessions.pfs_task_sessions,
- smp_processor_id(), pfm_sessions.pfs_sys_session[smp_processor_id()] ? 1 : 0));
- UNLOCK_PFS();
- return 0;
-undo:
- DBprintk(("system wide not possible, conflicting session [%d] on CPU%d\n",
- pfm_sessions.pfs_sys_session[i]->pid, i));
-
- for(i=0; undo_mask; i++, undo_mask >>=1) {
- pfm_sessions.pfs_sys_session[i] = NULL;
}
-abort:
- UNLOCK_PFS();
-
- return -EBUSY;
+ /* probably more to add here */
+ return 0;
}
static int
-pfm_unreserve_session(struct task_struct *task, int is_syswide, unsigned long cpu_mask)
+pfm_setup_buffer_fmt(struct task_struct *task, pfm_context_t *ctx, unsigned int ctx_flags,
+ unsigned int cpu, pfarg_context_t *arg)
{
- pfm_context_t *ctx;
- unsigned long m;
- unsigned int n, i;
+ pfm_buffer_fmt_t *fmt = NULL;
+ unsigned long size = 0UL;
+ void *uaddr = NULL;
+ void *fmt_arg = NULL;
+ int ret = 0;
+#define PFM_CTXARG_BUF_ARG(a) (pfm_buffer_fmt_t *)(a+1)
- ctx = task ? task->thread.pfm_context : NULL;
+ /* invoke and lock buffer format, if found */
+ fmt = pfm_find_buffer_fmt(arg->ctx_smpl_buf_id, 0);
+ if (fmt == NULL) {
+ DPRINT(("[%d] cannot find buffer format\n", task->pid));
+ return -EINVAL;
+ }
/*
- * validy checks on cpu_mask have been done upstream
+ * buffer argument MUST be contiguous to pfarg_context_t
*/
- LOCK_PFS();
+ if (fmt->fmt_arg_size) fmt_arg = PFM_CTXARG_BUF_ARG(arg);
- DBprintk(("[%d] sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu_mask=0x%lx\n",
- task->pid,
- pfm_sessions.pfs_sys_sessions,
- pfm_sessions.pfs_task_sessions,
- pfm_sessions.pfs_sys_use_dbregs,
- is_syswide,
- cpu_mask));
+ ret = pfm_buf_fmt_validate(fmt, task, ctx_flags, cpu, fmt_arg);
+ DPRINT(("[%d] after validate(0x%x,%d,%p)=%d\n", task->pid, ctx_flags, cpu, fmt_arg, ret));
- if (is_syswide) {
- m = cpu_mask; n = 0;
- for(i=0; m; i++, m>>=1) {
- if ((m & 0x1) == 0UL) continue;
- pfm_sessions.pfs_sys_session[i] = NULL;
- n++;
- }
- /*
- * would not work with perfmon+more than one bit in cpu_mask
+ if (ret) goto error;
+
+ /* link buffer format and context */
+ ctx->ctx_buf_fmt = fmt;
+
+ /*
+ * check if buffer format wants to use perfmon buffer allocation/mapping service
+ */
+ ret = pfm_buf_fmt_getsize(fmt, task, ctx_flags, cpu, fmt_arg, &size);
+ if (ret) goto error;
+
+ if (size) {
+ /*
+ * buffer is always remapped into the caller's address space
*/
- if (ctx && ctx->ctx_fl_using_dbreg) {
- if (pfm_sessions.pfs_sys_use_dbregs == 0) {
- printk(KERN_DEBUG "perfmon: invalid release for [%d] "
- "sys_use_dbregs=0\n", task->pid);
- } else {
- pfm_sessions.pfs_sys_use_dbregs--;
- }
- }
- pfm_sessions.pfs_sys_sessions -= n;
+ ret = pfm_smpl_buffer_alloc(current, ctx, size, &uaddr);
+ if (ret) goto error;
- DBprintk(("CPU%d sys_sessions=%u\n",
- smp_processor_id(), pfm_sessions.pfs_sys_sessions));
- } else {
- pfm_sessions.pfs_task_sessions--;
- DBprintk(("[%d] task_sessions=%u\n",
- task->pid, pfm_sessions.pfs_task_sessions));
+ /* keep track of user address of buffer */
+ arg->ctx_smpl_vaddr = uaddr;
}
+ ret = pfm_buf_fmt_init(fmt, task, ctx->ctx_smpl_hdr, ctx_flags, cpu, fmt_arg);
- UNLOCK_PFS();
-
- return 0;
+error:
+ return ret;
}
-/*
- * XXX: do something better here
- */
-static int
-pfm_bad_permissions(struct task_struct *task)
+static void
+pfm_reset_pmu_state(pfm_context_t *ctx)
{
- /* stolen from bad_signal() */
- return (current->session != task->session)
- && (current->euid ^ task->suid) && (current->euid ^ task->uid)
- && (current->uid ^ task->suid) && (current->uid ^ task->uid);
-}
+ int i;
+ /*
+ * install reset values for PMC.
+ */
+ for (i=1; PMC_IS_LAST(i) == 0; i++) {
+ if (PMC_IS_IMPL(i) == 0) continue;
+ ctx->ctx_pmcs[i] = PMC_DFL_VAL(i);
+ DPRINT(("pmc[%d]=0x%lx\n", i, ctx->ctx_pmcs[i]));
+ }
+ /*
+ * PMD registers are set to 0UL when the context in memset()
+ */
-static int
-pfx_is_sane(struct task_struct *task, pfarg_context_t *pfx)
-{
- unsigned long smpl_pmds = pfx->ctx_smpl_regs[0];
- int ctx_flags;
- int cpu;
+ /*
+ * On context switched restore, we must restore ALL pmc and ALL pmd even
+ * when they are not actively used by the task. In UP, the incoming process
+ * may otherwise pick up left over PMC, PMD state from the previous process.
+ * As opposed to PMD, stale PMC can cause harm to the incoming
+ * process because they may change what is being measured.
+ * Therefore, we must systematically reinstall the entire
+ * PMC state. In SMP, the same thing is possible on the
+ * same CPU but also on between 2 CPUs.
+ *
+ * The problem with PMD is information leaking especially
+ * to user level when psr.sp=0
+ *
+ * There is unfortunately no easy way to avoid this problem
+ * on either UP or SMP. This definitively slows down the
+ * pfm_load_regs() function.
+ */
- /* valid signal */
+ /*
+ * bitmask of all PMCs accessible to this context
+ *
+ * PMC0 is treated differently.
+ */
+ ctx->ctx_all_pmcs[0] = pmu_conf.impl_pmcs[0] & ~0x1;
- /* cannot send to process 1, 0 means do not notify */
- if (pfx->ctx_notify_pid == 1) {
- DBprintk(("invalid notify_pid %d\n", pfx->ctx_notify_pid));
- return -EINVAL;
- }
- ctx_flags = pfx->ctx_flags;
+ /*
+ * bitmask of all PMDs that are accesible to this context
+ */
+ ctx->ctx_all_pmds[0] = pmu_conf.impl_pmds[0];
- if ((ctx_flags & PFM_FL_INHERIT_MASK) == (PFM_FL_INHERIT_ONCE|PFM_FL_INHERIT_ALL)) {
- DBprintk(("invalid inherit mask 0x%x\n",ctx_flags & PFM_FL_INHERIT_MASK));
- return -EINVAL;
- }
+ DPRINT(("<%d> all_pmcs=0x%lx all_pmds=0x%lx\n", ctx->ctx_fd, ctx->ctx_all_pmcs[0],ctx->ctx_all_pmds[0]));
- if (ctx_flags & PFM_FL_SYSTEM_WIDE) {
- DBprintk(("cpu_mask=0x%lx\n", pfx->ctx_cpu_mask));
- /*
- * cannot block in this mode
- */
- if (ctx_flags & PFM_FL_NOTIFY_BLOCK) {
- DBprintk(("cannot use blocking mode when in system wide monitoring\n"));
- return -EINVAL;
- }
- /*
- * must only have one bit set in the CPU mask
- */
- if (hweight64(pfx->ctx_cpu_mask) != 1UL) {
- DBprintk(("invalid CPU mask specified\n"));
- return -EINVAL;
- }
- /*
- * and it must be a valid CPU
- */
- cpu = ffz(~pfx->ctx_cpu_mask);
-#ifdef CONFIG_SMP
- if (cpu_online(cpu) == 0) {
-#else
- if (cpu != 0) {
-#endif
- DBprintk(("CPU%d is not online\n", cpu));
- return -EINVAL;
- }
+ /*
+ * useful in case of re-enable after disable
+ */
+ ctx->ctx_used_ibrs[0] = 0UL;
+ ctx->ctx_used_dbrs[0] = 0UL;
+}
- /*
- * check for pre-existing pinning, if conflicting reject
- */
- if (task->cpus_allowed != ~0UL && (task->cpus_allowed & (1UL<<cpu)) == 0) {
- DBprintk(("[%d] pinned on 0x%lx, mask for CPU%d \n", task->pid,
- task->cpus_allowed, cpu));
- return -EINVAL;
- }
+static int
+pfm_ctx_getsize(void *arg, size_t *sz)
+{
+ pfarg_context_t *req = (pfarg_context_t *)arg;
+ pfm_buffer_fmt_t *fmt;
- } else {
- /*
- * must provide a target for the signal in blocking mode even when
- * no counter is configured with PFM_FL_REG_OVFL_NOTIFY
- */
- if ((ctx_flags & PFM_FL_NOTIFY_BLOCK) && pfx->ctx_notify_pid == 0) {
- DBprintk(("must have notify_pid when blocking for [%d]\n", task->pid));
- return -EINVAL;
- }
-#if 0
- if ((ctx_flags & PFM_FL_NOTIFY_BLOCK) && pfx->ctx_notify_pid == task->pid) {
- DBprintk(("cannot notify self when blocking for [%d]\n", task->pid));
- return -EINVAL;
- }
-#endif
- }
- /* verify validity of smpl_regs */
- if ((smpl_pmds & pmu_conf.impl_pmds[0]) != smpl_pmds) {
- DBprintk(("invalid smpl_regs 0x%lx\n", smpl_pmds));
+ *sz = 0;
+
+ if (!pfm_uuid_cmp(req->ctx_smpl_buf_id, pfm_null_uuid)) return 0;
+
+ /* no buffer locking here, will be called again */
+ fmt = pfm_find_buffer_fmt(req->ctx_smpl_buf_id, 1);
+ if (fmt == NULL) {
+ DPRINT(("cannot find buffer format\n"));
return -EINVAL;
}
- /* probably more to add here */
+ /* get just enough to copy in user parameters */
+ *sz = fmt->fmt_arg_size;
+ DPRINT(("arg_size=%lu\n", *sz));
return 0;
}
+
+
+/*
+ * cannot attach if :
+ * - kernel task
+ * - task not owned by caller
+ * - task incompatible with context mode
+ */
static int
-pfm_context_create(struct task_struct *task, pfm_context_t *ctx, void *req, int count,
- struct pt_regs *regs)
+pfm_task_incompatible(pfm_context_t *ctx, struct task_struct *task)
{
- pfarg_context_t tmp;
- void *uaddr = NULL;
- int ret;
- int ctx_flags;
- pid_t notify_pid;
+ /*
+ * no kernel task or task not owner by caller
+ */
+ if (task->mm == NULL) {
+ DPRINT(("[%d] task [%d] has not memory context (kernel thread)\n", current->pid, task->pid));
+ return -EPERM;
+ }
+ if (pfm_bad_permissions(task)) {
+ DPRINT(("[%d] no permission to attach to [%d]\n", current->pid, task->pid));
+ return -EPERM;
+ }
+ /*
+ * cannot block in self-monitoring mode
+ */
+ if (CTX_OVFL_NOBLOCK(ctx) == 0 && task == current) {
+ DPRINT(("cannot load a blocking context on self for [%d]\n", task->pid));
+ return -EINVAL;
+ }
+
+ if (task->state == TASK_ZOMBIE) {
+ DPRINT(("[%d] cannot attach to zombie task [%d]\n", current->pid, task->pid));
+ return -EBUSY;
+ }
- /* a context has already been defined */
- if (ctx) return -EBUSY;
+ /*
+ * always ok for self
+ */
+ if (task == current) return 0;
+ if (task->state != TASK_STOPPED) {
+ DPRINT(("[%d] cannot attach to non-stopped task [%d] state=%ld\n", current->pid, task->pid, task->state));
+ return -EBUSY;
+ }
/*
- * not yet supported
+ * make sure the task is off any CPU
*/
- if (task != current) return -EINVAL;
+ pfm_wait_task_inactive(task);
- if (__copy_from_user(&tmp, req, sizeof(tmp))) return -EFAULT;
+ /* more to come... */
- ret = pfx_is_sane(task, &tmp);
- if (ret < 0) return ret;
+ return 0;
+}
- ctx_flags = tmp.ctx_flags;
+static int
+pfm_get_task(pfm_context_t *ctx, pid_t pid, struct task_struct **task)
+{
+ struct task_struct *p = current;
+ int ret;
- ret = pfm_reserve_session(task, ctx_flags & PFM_FL_SYSTEM_WIDE, tmp.ctx_cpu_mask);
- if (ret) goto abort;
+ /* XXX: need to add more checks here */
+ if (pid < 2) return -EPERM;
- ret = -ENOMEM;
+ if (pid != current->pid) {
- ctx = pfm_context_alloc();
- if (!ctx) goto error;
+ read_lock(&tasklist_lock);
- /* record the creator (important for inheritance) */
- ctx->ctx_owner = current;
+ p = find_task_by_pid(pid);
- notify_pid = tmp.ctx_notify_pid;
+ /* make sure task cannot go away while we operate on it */
+ if (p) get_task_struct(p);
- spin_lock_init(&ctx->ctx_lock);
+ read_unlock(&tasklist_lock);
- if (notify_pid == current->pid) {
+ if (p == NULL) return -ESRCH;
+ }
- ctx->ctx_notify_task = current;
- task->thread.pfm_context = ctx;
+ ret = pfm_task_incompatible(ctx, p);
+ if (ret == 0) {
+ *task = p;
+ } else if (p != current) {
+ pfm_put_task(p);
+ }
+ return ret;
+}
- } else if (notify_pid!=0) {
- struct task_struct *notify_task;
- read_lock(&tasklist_lock);
- notify_task = find_task_by_pid(notify_pid);
+static int
+pfm_context_create(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ pfarg_context_t *req = (pfarg_context_t *)arg;
+ struct file *filp;
+ int ctx_flags;
+ int ret;
- if (notify_task) {
+ /* let's check the arguments first */
+ ret = pfarg_is_sane(current, req);
+ if (ret < 0) return ret;
- ret = -EPERM;
+ ctx_flags = req->ctx_flags;
- /*
- * check if we can send this task a signal
- */
- if (pfm_bad_permissions(notify_task)) {
- read_unlock(&tasklist_lock);
- goto buffer_error;
- }
+ ret = -ENOMEM;
- /*
- * make visible
- * must be done inside critical section
- *
- * if the initialization does not go through it is still
- * okay because child will do the scan for nothing which
- * won't hurt.
- */
- task->thread.pfm_context = ctx;
+ ctx = pfm_context_alloc();
+ if (!ctx) goto error;
- /*
- * will cause task to check on exit for monitored
- * processes that would notify it. see release_thread()
- * Note: the scan MUST be done in release thread, once the
- * task has been detached from the tasklist otherwise you are
- * exposed to race conditions.
- */
- atomic_add(1, &ctx->ctx_notify_task->thread.pfm_notifiers_check);
+ req->ctx_fd = ctx->ctx_fd = pfm_alloc_fd(&filp);
+ if (req->ctx_fd < 0) goto error_file;
- ctx->ctx_notify_task = notify_task;
- }
- read_unlock(&tasklist_lock);
- }
+ /*
+ * attach context to file
+ */
+ filp->private_data = ctx;
/*
- * notification process does not exist
+ * does the user want to sample?
*/
- if (notify_pid != 0 && ctx->ctx_notify_task == NULL) {
- ret = -EINVAL;
- goto buffer_error;
+ if (pfm_uuid_cmp(req->ctx_smpl_buf_id, pfm_null_uuid)) {
+ ret = pfm_setup_buffer_fmt(current, ctx, ctx_flags, 0, req);
+ if (ret) goto buffer_error;
}
- if (tmp.ctx_smpl_entries) {
- DBprintk(("sampling entries=%lu\n",tmp.ctx_smpl_entries));
-
- ret = pfm_smpl_buffer_alloc(ctx, tmp.ctx_smpl_regs,
- tmp.ctx_smpl_entries, &uaddr);
- if (ret<0) goto buffer_error;
+ /*
+ * init context protection lock
+ */
+ spin_lock_init(&ctx->ctx_lock);
- tmp.ctx_smpl_vaddr = uaddr;
- }
- /* initialization of context's flags */
- ctx->ctx_fl_inherit = ctx_flags & PFM_FL_INHERIT_MASK;
- ctx->ctx_fl_block = (ctx_flags & PFM_FL_NOTIFY_BLOCK) ? 1 : 0;
- ctx->ctx_fl_system = (ctx_flags & PFM_FL_SYSTEM_WIDE) ? 1: 0;
- ctx->ctx_fl_excl_idle = (ctx_flags & PFM_FL_EXCL_IDLE) ? 1: 0;
- ctx->ctx_fl_unsecure = (ctx_flags & PFM_FL_UNSECURE) ? 1: 0;
- ctx->ctx_fl_frozen = 0;
- ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_NONE;
+ /*
+ * context is unloaded
+ */
+ CTX_UNLOADED(ctx);
/*
- * setting this flag to 0 here means, that the creator or the task that the
- * context is being attached are granted access. Given that a context can only
- * be created for the calling process this, in effect only allows the creator
- * to access the context. See pfm_protect() for more.
+ * initialization of context's flags
+ */
+ ctx->ctx_fl_block = (ctx_flags & PFM_FL_NOTIFY_BLOCK) ? 1 : 0;
+ ctx->ctx_fl_system = (ctx_flags & PFM_FL_SYSTEM_WIDE) ? 1: 0;
+ ctx->ctx_fl_unsecure = (ctx_flags & PFM_FL_UNSECURE) ? 1: 0;
+ ctx->ctx_fl_is_sampling = ctx->ctx_buf_fmt ? 1 : 0; /* assume record() is defined */
+ ctx->ctx_fl_no_msg = (ctx_flags & PFM_FL_OVFL_NO_MSG) ? 1: 0;
+ /*
+ * will move to set properties
+ * ctx->ctx_fl_excl_idle = (ctx_flags & PFM_FL_EXCL_IDLE) ? 1: 0;
*/
- ctx->ctx_fl_protected = 0;
- /* for system wide mode only (only 1 bit set) */
- ctx->ctx_cpu = ffz(~tmp.ctx_cpu_mask);
-
- atomic_set(&ctx->ctx_last_cpu,-1); /* SMP only, means no CPU */
-
- sema_init(&ctx->ctx_restart_sem, 0); /* init this semaphore to locked */
-
- if (__copy_to_user(req, &tmp, sizeof(tmp))) {
- ret = -EFAULT;
- goto buffer_error;
- }
-
- DBprintk(("context=%p, pid=%d notify_task=%p\n",
- (void *)ctx, task->pid, ctx->ctx_notify_task));
+ /*
+ * init restart semaphore to locked
+ */
+ sema_init(&ctx->ctx_restart_sem, 0);
- DBprintk(("context=%p, pid=%d flags=0x%x inherit=%d block=%d system=%d excl_idle=%d unsecure=%d\n",
- (void *)ctx, task->pid, ctx_flags, ctx->ctx_fl_inherit,
- ctx->ctx_fl_block, ctx->ctx_fl_system,
- ctx->ctx_fl_excl_idle,
- ctx->ctx_fl_unsecure));
+ /*
+ * activation is used in SMP only
+ */
+ ctx->ctx_last_activation = PFM_INVALID_ACTIVATION;
+ SET_LAST_CPU(ctx, -1);
/*
- * when no notification is required, we can make this visible at the last moment
+ * initialize notification message queue
*/
- if (notify_pid == 0) task->thread.pfm_context = ctx;
+ ctx->ctx_msgq_head = ctx->ctx_msgq_tail = 0;
+ init_waitqueue_head(&ctx->ctx_msgq_wait);
+ init_waitqueue_head(&ctx->ctx_zombieq);
+
+ DPRINT(("ctx=%p flags=0x%x system=%d notify_block=%d excl_idle=%d unsecure=%d no_msg=%d ctx_fd=%d \n",
+ ctx,
+ ctx_flags,
+ ctx->ctx_fl_system,
+ ctx->ctx_fl_block,
+ ctx->ctx_fl_excl_idle,
+ ctx->ctx_fl_unsecure,
+ ctx->ctx_fl_no_msg,
+ ctx->ctx_fd));
+
/*
- * pin task to CPU and force reschedule on exit to ensure
- * that when back to user level the task runs on the designated
- * CPU.
+ * initialize soft PMU state
*/
- if (ctx->ctx_fl_system) {
- ctx->ctx_saved_cpus_allowed = task->cpus_allowed;
- set_cpus_allowed(task, tmp.ctx_cpu_mask);
- DBprintk(("[%d] rescheduled allowed=0x%lx\n", task->pid, task->cpus_allowed));
- }
+ pfm_reset_pmu_state(ctx);
return 0;
buffer_error:
+ pfm_free_fd(ctx->ctx_fd, filp);
+
+ if (ctx->ctx_buf_fmt) {
+ pfm_buf_fmt_exit(ctx->ctx_buf_fmt, current, NULL, regs);
+ }
+error_file:
pfm_context_free(ctx);
-error:
- pfm_unreserve_session(task, ctx_flags & PFM_FL_SYSTEM_WIDE , tmp.ctx_cpu_mask);
-abort:
- /* make sure we don't leave anything behind */
- task->thread.pfm_context = NULL;
+error:
return ret;
}
}
static void
+pfm_reset_regs_masked(pfm_context_t *ctx, unsigned long *ovfl_regs, int flag)
+{
+ unsigned long mask = ovfl_regs[0];
+ unsigned long reset_others = 0UL;
+ unsigned long val;
+ int i, is_long_reset = (flag == PFM_PMD_LONG_RESET);
+
+ DPRINT_ovfl(("ovfl_regs=0x%lx flag=%d\n", ovfl_regs[0], flag));
+
+ if (flag == PFM_PMD_NO_RESET) return;
+
+ /*
+ * now restore reset value on sampling overflowed counters
+ */
+ mask >>= PMU_FIRST_COUNTER;
+ for(i = PMU_FIRST_COUNTER; mask; i++, mask >>= 1) {
+ if (mask & 0x1) {
+ ctx->ctx_pmds[i].val = val = pfm_new_counter_value(ctx->ctx_pmds+ i, is_long_reset);
+ reset_others |= ctx->ctx_pmds[i].reset_pmds[0];
+
+ DPRINT_ovfl((" %s reset ctx_pmds[%d]=%lx\n",
+ is_long_reset ? "long" : "short", i, val));
+ }
+ }
+
+ /*
+ * Now take care of resetting the other registers
+ */
+ for(i = 0; reset_others; i++, reset_others >>= 1) {
+
+ if ((reset_others & 0x1) == 0) continue;
+
+ ctx->ctx_pmds[i].val = val = pfm_new_counter_value(ctx->ctx_pmds + i, is_long_reset);
+
+ DPRINT_ovfl(("%s reset_others pmd[%d]=%lx\n",
+ is_long_reset ? "long" : "short", i, val));
+ }
+}
+
+static void
pfm_reset_regs(pfm_context_t *ctx, unsigned long *ovfl_regs, int flag)
{
unsigned long mask = ovfl_regs[0];
unsigned long val;
int i, is_long_reset = (flag == PFM_PMD_LONG_RESET);
+ DPRINT_ovfl(("ovfl_regs=0x%lx flag=%d\n", ovfl_regs[0], flag));
+
+ if (flag == PFM_PMD_NO_RESET) return;
+
+ if (CTX_IS_MASKED(ctx)) {
+ pfm_reset_regs_masked(ctx, ovfl_regs, flag);
+ return;
+ }
+
/*
* now restore reset value on sampling overflowed counters
*/
mask >>= PMU_FIRST_COUNTER;
for(i = PMU_FIRST_COUNTER; mask; i++, mask >>= 1) {
if (mask & 0x1) {
- val = pfm_new_counter_value(ctx->ctx_soft_pmds + i, is_long_reset);
- reset_others |= ctx->ctx_soft_pmds[i].reset_pmds[0];
+ val = pfm_new_counter_value(ctx->ctx_pmds+ i, is_long_reset);
+ reset_others |= ctx->ctx_pmds[i].reset_pmds[0];
- DBprintk_ovfl(("[%d] %s reset soft_pmd[%d]=%lx\n", current->pid,
+ DPRINT_ovfl((" %s reset ctx_pmds[%d]=%lx\n",
is_long_reset ? "long" : "short", i, val));
- /* upper part is ignored on rval */
pfm_write_soft_counter(ctx, i, val);
}
}
if ((reset_others & 0x1) == 0) continue;
- val = pfm_new_counter_value(ctx->ctx_soft_pmds + i, is_long_reset);
+ val = pfm_new_counter_value(ctx->ctx_pmds + i, is_long_reset);
if (PMD_IS_COUNTING(i)) {
pfm_write_soft_counter(ctx, i, val);
} else {
ia64_set_pmd(i, val);
}
- DBprintk_ovfl(("[%d] %s reset_others pmd[%d]=%lx\n", current->pid,
+ DPRINT_ovfl(("%s reset_others pmd[%d]=%lx\n",
is_long_reset ? "long" : "short", i, val));
}
ia64_srlz_d();
}
static int
-pfm_write_pmcs(struct task_struct *task, pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+pfm_write_pmcs(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
{
- struct thread_struct *th = &task->thread;
- pfarg_reg_t tmp, *req = (pfarg_reg_t *)arg;
- unsigned long value, reset_pmds;
+ struct thread_struct *thread = NULL;
+ pfarg_reg_t *req = (pfarg_reg_t *)arg;
+ unsigned long value;
+ unsigned long smpl_pmds, reset_pmds;
unsigned int cnum, reg_flags, flags;
- int i;
+ int i, can_access_pmu = 0, is_loaded;
+ int is_monitor, is_counting;
int ret = -EINVAL;
+#define PFM_CHECK_PMC_PM(x, y, z) ((x)->ctx_fl_system ^ PMC_PM(y, z))
- /* we don't quite support this right now */
- if (task != current) return -EINVAL;
+ if (CTX_IS_DEAD(ctx)) return -EINVAL;
- if (!CTX_IS_ENABLED(ctx)) return -EINVAL;
+ is_loaded = CTX_IS_LOADED(ctx);
- /* XXX: ctx locking may be required here */
+ if (is_loaded) {
+ thread = &ctx->ctx_task->thread;
+ can_access_pmu = GET_PMU_OWNER() == ctx->ctx_task? 1 : 0;
+ /*
+ * In system wide and when the context is loaded, access can only happen
+ * when the caller is running on the CPU being monitored by the session.
+ * It does not have to be the owner (ctx_task) of the context per se.
+ */
+ if (ctx->ctx_fl_system && ctx->ctx_cpu != smp_processor_id()) {
+ DPRINT(("[%d] should be running on CPU%d\n", current->pid, ctx->ctx_cpu));
+ return -EBUSY;
+ }
+ }
for (i = 0; i < count; i++, req++) {
- if (__copy_from_user(&tmp, req, sizeof(tmp))) return -EFAULT;
-
- cnum = tmp.reg_num;
- reg_flags = tmp.reg_flags;
- value = tmp.reg_value;
- reset_pmds = tmp.reg_reset_pmds[0];
+ cnum = req->reg_num;
+ reg_flags = req->reg_flags;
+ value = req->reg_value;
+ smpl_pmds = req->reg_smpl_pmds[0];
+ reset_pmds = req->reg_reset_pmds[0];
flags = 0;
- /*
+ is_counting = PMC_IS_COUNTING(cnum);
+ is_monitor = PMC_IS_MONITOR(cnum);
+
+ /*
* we reject all non implemented PMC as well
* as attempts to modify PMC[0-3] which are used
* as status registers by the PMU
*/
if (!PMC_IS_IMPL(cnum) || cnum < 4) {
- DBprintk(("pmc[%u] is unimplemented or invalid\n", cnum));
+ DPRINT(("pmc%u is unimplemented or invalid\n", cnum));
goto error;
}
/*
- * A PMC used to configure monitors must be:
- * - system-wide session: privileged monitor
- * - per-task : user monitor
- * any other configuration is rejected.
+ * If the PMC is a monitor, then if the value is not the default:
+ * - system-wide session: PMCx.pm=1 (privileged monitor)
+ * - per-task : PMCx.pm=0 (user monitor)
*/
- if (PMC_IS_MONITOR(cnum) || PMC_IS_COUNTING(cnum)) {
- DBprintk(("pmc[%u].pm=%ld\n", cnum, PMC_PM(cnum, value)));
-
- if (ctx->ctx_fl_system ^ PMC_PM(cnum, value)) {
- DBprintk(("pmc_pm=%ld fl_system=%d\n", PMC_PM(cnum, value), ctx->ctx_fl_system));
- goto error;
- }
+ if ((is_monitor || is_counting) && value != PMC_DFL_VAL(i) && PFM_CHECK_PMC_PM(ctx, cnum, value)) {
+ DPRINT(("pmc%u pmc_pm=%ld fl_system=%d\n",
+ cnum,
+ PMC_PM(cnum, value),
+ ctx->ctx_fl_system));
+ goto error;
}
- if (PMC_IS_COUNTING(cnum)) {
+
+ if (is_counting) {
pfm_monitor_t *p = (pfm_monitor_t *)&value;
/*
* enforce generation of overflow interrupt. Necessary on all
p->pmc_oi = 1;
if (reg_flags & PFM_REGFL_OVFL_NOTIFY) {
- /*
- * must have a target for the signal
- */
- if (ctx->ctx_notify_task == NULL) {
- DBprintk(("cannot set ovfl_notify: no notify_task\n"));
- goto error;
- }
flags |= PFM_REGFL_OVFL_NOTIFY;
}
if (reg_flags & PFM_REGFL_RANDOM) flags |= PFM_REGFL_RANDOM;
+ /* verify validity of smpl_pmds */
+ if ((smpl_pmds & pmu_conf.impl_pmds[0]) != smpl_pmds) {
+ DPRINT(("invalid smpl_pmds 0x%lx for pmc%u\n", smpl_pmds, cnum));
+ goto error;
+ }
+
/* verify validity of reset_pmds */
if ((reset_pmds & pmu_conf.impl_pmds[0]) != reset_pmds) {
- DBprintk(("invalid reset_pmds 0x%lx for pmc%u\n", reset_pmds, cnum));
+ DPRINT(("invalid reset_pmds 0x%lx for pmc%u\n", reset_pmds, cnum));
goto error;
}
- } else if (reg_flags & (PFM_REGFL_OVFL_NOTIFY|PFM_REGFL_RANDOM)) {
- DBprintk(("cannot set ovfl_notify or random on pmc%u\n", cnum));
+ } else {
+ if (reg_flags & (PFM_REGFL_OVFL_NOTIFY|PFM_REGFL_RANDOM)) {
+ DPRINT(("cannot set ovfl_notify or random on pmc%u\n", cnum));
goto error;
+ }
+ /* eventid on non-counting monitors are ignored */
}
/*
* execute write checker, if any
*/
if (PMC_WR_FUNC(cnum)) {
- ret = PMC_WR_FUNC(cnum)(task, cnum, &value, regs);
+ ret = PMC_WR_FUNC(cnum)(ctx->ctx_task, ctx, cnum, &value, regs);
if (ret) goto error;
ret = -EINVAL;
}
/*
* no error on this register
*/
- PFM_REG_RETFLAG_SET(tmp.reg_flags, 0);
-
- /*
- * update register return value, abort all if problem during copy.
- * we only modify the reg_flags field. no check mode is fine because
- * access has been verified upfront in sys_perfmonctl().
- *
- * If this fails, then the software state is not modified
- */
- if (__put_user(tmp.reg_flags, &req->reg_flags)) return -EFAULT;
+ PFM_REG_RETFLAG_SET(req->reg_flags, 0);
/*
* Now we commit the changes to the software state
*/
- /*
- * full flag update each time a register is programmed
+ /*
+ * update overflow information
*/
- ctx->ctx_soft_pmds[cnum].flags = flags;
+ if (is_counting) {
+ /*
+ * full flag update each time a register is programmed
+ */
+ ctx->ctx_pmds[cnum].flags = flags;
- if (PMC_IS_COUNTING(cnum)) {
- ctx->ctx_soft_pmds[cnum].reset_pmds[0] = reset_pmds;
+ ctx->ctx_pmds[cnum].reset_pmds[0] = reset_pmds;
+ ctx->ctx_pmds[cnum].smpl_pmds[0] = smpl_pmds;
+ ctx->ctx_pmds[cnum].eventid = req->reg_smpl_eventid;
- /* mark all PMDS to be accessed as used */
+ /*
+ * Mark all PMDS to be accessed as used.
+ *
+ * We do not keep track of PMC because we have to
+ * systematically restore ALL of them.
+ *
+ * We do not update the used_monitors mask, because
+ * if we have not programmed them, then will be in
+ * a quiescent state, therefore we will not need to
+ * mask/restore then when context is MASKED.
+ */
CTX_USED_PMD(ctx, reset_pmds);
+ CTX_USED_PMD(ctx, smpl_pmds);
+ /*
+ * make sure we do not try to reset on
+ * restart because we have established new values
+ */
+ if (CTX_IS_MASKED(ctx)) ctx->ctx_ovfl_regs[0] &= ~1UL << cnum;
}
-
/*
* Needed in case the user does not initialize the equivalent
- * PMD. Clearing is done in reset_pmu() so there is no possible
- * leak here.
+ * PMD. Clearing is done indirectly via pfm_reset_pmu_state() so there is no
+ * possible leak here.
*/
CTX_USED_PMD(ctx, pmu_conf.pmc_desc[cnum].dep_pmd[0]);
- /*
- * keep copy the pmc, used for register reload
+ /*
+ * keep track of the monitor PMC that we are using.
+ * we save the value of the pmc in ctx_pmcs[] and if
+ * the monitoring is not stopped for the context we also
+ * place it in the saved state area so that it will be
+ * picked up later by the context switch code.
+ *
+ * The value in ctx_pmcs[] can only be changed in pfm_write_pmcs().
+ *
+ * The value in t->pmc[] may be modified on overflow, i.e., when
+ * monitoring needs to be stopped.
+ */
+ if (is_monitor) CTX_USED_MONITOR(ctx, 1UL << cnum);
+
+ /*
+ * update context state
*/
- th->pmc[cnum] = value;
+ ctx->ctx_pmcs[cnum] = value;
- ia64_set_pmc(cnum, value);
+ if (is_loaded) {
+ /*
+ * write thread state
+ */
+ if (ctx->ctx_fl_system == 0) thread->pmcs[cnum] = value;
- DBprintk(("[%d] pmc[%u]=0x%lx flags=0x%x used_pmds=0x%lx\n",
- task->pid, cnum, value,
- ctx->ctx_soft_pmds[cnum].flags,
- ctx->ctx_used_pmds[0]));
+ /*
+ * write hardware register if we can
+ */
+ if (can_access_pmu) {
+ ia64_set_pmc(cnum, value);
+ }
+#ifdef CONFIG_SMP
+ else {
+ /*
+ * per-task SMP only here
+ *
+ * we are guaranteed that the task is not running on the other CPU,
+ * we indicate that this PMD will need to be reloaded if the task
+ * is rescheduled on the CPU it ran last on.
+ */
+ ctx->ctx_reload_pmcs[0] |= 1UL << cnum;
+ }
+#endif
+ }
+ DPRINT(("pmc[%u]=0x%lx loaded=%d access_pmu=%d all_pmcs=0x%lx used_pmds=0x%lx eventid=%ld smpl_pmds=0x%lx reset_pmds=0x%lx reloads_pmcs=0x%lx used_monitors=0x%lx ovfl_regs=0x%lx\n",
+ cnum,
+ value,
+ is_loaded,
+ can_access_pmu,
+ ctx->ctx_all_pmcs[0],
+ ctx->ctx_used_pmds[0],
+ ctx->ctx_pmds[cnum].eventid,
+ smpl_pmds,
+ reset_pmds,
+ ctx->ctx_reload_pmcs[0],
+ ctx->ctx_used_monitors[0],
+ ctx->ctx_ovfl_regs[0]));
}
- return 0;
+ /*
+ * make sure the changes are visible
+ */
+ if (can_access_pmu) ia64_srlz_d();
+ return 0;
error:
- PFM_REG_RETFLAG_SET(tmp.reg_flags, PFM_REG_RETFL_EINVAL);
+ PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL);
- if (__put_user(tmp.reg_flags, &req->reg_flags)) ret = -EFAULT;
+ req->reg_flags = PFM_REG_RETFL_EINVAL;
- DBprintk(("[%d] pmc[%u]=0x%lx error %d\n", task->pid, cnum, value, ret));
+ DPRINT(("pmc[%u]=0x%lx error %d\n", cnum, value, ret));
return ret;
}
static int
-pfm_write_pmds(struct task_struct *task, pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+pfm_write_pmds(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
{
- pfarg_reg_t tmp, *req = (pfarg_reg_t *)arg;
+ struct thread_struct *thread = NULL;
+ pfarg_reg_t *req = (pfarg_reg_t *)arg;
unsigned long value, hw_value;
unsigned int cnum;
- int i;
+ int i, can_access_pmu = 0;
+ int is_counting, is_loaded;
int ret = -EINVAL;
- /* we don't quite support this right now */
- if (task != current) return -EINVAL;
-
- /*
- * Cannot do anything before PMU is enabled
- */
- if (!CTX_IS_ENABLED(ctx)) return -EINVAL;
- preempt_disable();
+ if (CTX_IS_DEAD(ctx)) return -EINVAL;
- /* XXX: ctx locking may be required here */
+ is_loaded = CTX_IS_LOADED(ctx);
+ /*
+ * on both UP and SMP, we can only write to the PMC when the task is
+ * the owner of the local PMU.
+ */
+ if (is_loaded) {
+ thread = &ctx->ctx_task->thread;
+ can_access_pmu = GET_PMU_OWNER() == ctx->ctx_task ? 1 : 0;
+ /*
+ * In system wide and when the context is loaded, access can only happen
+ * when the caller is running on the CPU being monitored by the session.
+ * It does not have to be the owner (ctx_task) of the context per se.
+ */
+ if (ctx->ctx_fl_system && ctx->ctx_cpu != smp_processor_id()) {
+ DPRINT(("[%d] should be running on CPU%d\n", current->pid, ctx->ctx_cpu));
+ return -EBUSY;
+ }
+ }
for (i = 0; i < count; i++, req++) {
- if (__copy_from_user(&tmp, req, sizeof(tmp))) return -EFAULT;
-
- cnum = tmp.reg_num;
- value = tmp.reg_value;
+ cnum = req->reg_num;
+ value = req->reg_value;
if (!PMD_IS_IMPL(cnum)) {
- DBprintk(("pmd[%u] is unimplemented or invalid\n", cnum));
+ DPRINT(("pmd[%u] is unimplemented or invalid\n", cnum));
goto abort_mission;
}
+ is_counting = PMD_IS_COUNTING(cnum);
/*
* execute write checker, if any
*/
if (PMD_WR_FUNC(cnum)) {
unsigned long v = value;
- ret = PMD_WR_FUNC(cnum)(task, cnum, &v, regs);
+
+ ret = PMD_WR_FUNC(cnum)(ctx->ctx_task, ctx, cnum, &v, regs);
if (ret) goto abort_mission;
+
value = v;
- ret = -EINVAL;
+ ret = -EINVAL;
}
- hw_value = value;
+
/*
* no error on this register
*/
- PFM_REG_RETFLAG_SET(tmp.reg_flags, 0);
-
- if (__put_user(tmp.reg_flags, &req->reg_flags)) return -EFAULT;
+ PFM_REG_RETFLAG_SET(req->reg_flags, 0);
/*
* now commit changes to software state
*/
+ hw_value = value;
- /* update virtualized (64bits) counter */
- if (PMD_IS_COUNTING(cnum)) {
- ctx->ctx_soft_pmds[cnum].lval = value;
- ctx->ctx_soft_pmds[cnum].val = value & ~pmu_conf.ovfl_val;
+ /*
+ * update virtualized (64bits) counter
+ */
+ if (is_counting) {
+ /*
+ * write context state
+ */
+ ctx->ctx_pmds[cnum].lval = value;
- hw_value = value & pmu_conf.ovfl_val;
+ /*
+ * when context is load we use the split value
+ */
+ if (is_loaded) {
+ hw_value = value & pmu_conf.ovfl_val;
+ value = value & ~pmu_conf.ovfl_val;
+ }
- ctx->ctx_soft_pmds[cnum].long_reset = tmp.reg_long_reset;
- ctx->ctx_soft_pmds[cnum].short_reset = tmp.reg_short_reset;
+ /*
+ * update sampling periods
+ */
+ ctx->ctx_pmds[cnum].long_reset = req->reg_long_reset;
+ ctx->ctx_pmds[cnum].short_reset = req->reg_short_reset;
- ctx->ctx_soft_pmds[cnum].seed = tmp.reg_random_seed;
- ctx->ctx_soft_pmds[cnum].mask = tmp.reg_random_mask;
+ /*
+ * update randomization parameters
+ */
+ ctx->ctx_pmds[cnum].seed = req->reg_random_seed;
+ ctx->ctx_pmds[cnum].mask = req->reg_random_mask;
}
- /* keep track of what we use */
- CTX_USED_PMD(ctx, pmu_conf.pmd_desc[(cnum)].dep_pmd[0]);
+ /*
+ * update context value
+ */
+ ctx->ctx_pmds[cnum].val = value;
+
+ /*
+ * Keep track of what we use
+ *
+ * We do not keep track of PMC because we have to
+ * systematically restore ALL of them.
+ */
+ CTX_USED_PMD(ctx, PMD_PMD_DEP(cnum));
- /* mark this register as used as well */
+ /*
+ * mark this PMD register used as well
+ */
CTX_USED_PMD(ctx, RDEP(cnum));
- /* writes to unimplemented part is ignored, so this is safe */
- ia64_set_pmd(cnum, hw_value);
+ /*
+ * make sure we do not try to reset on
+ * restart because we have established new values
+ */
+ if (is_counting && CTX_IS_MASKED(ctx)) {
+ ctx->ctx_ovfl_regs[0] &= ~1UL << cnum;
+ }
- /* to go away */
- ia64_srlz_d();
+ if (is_loaded) {
+ /*
+ * write thread state
+ */
+ if (ctx->ctx_fl_system == 0) thread->pmds[cnum] = hw_value;
+
+ /*
+ * write hardware register if we can
+ */
+ if (can_access_pmu) {
+ ia64_set_pmd(cnum, hw_value);
+ } else {
+#ifdef CONFIG_SMP
+ /*
+ * we are guaranteed that the task is not running on the other CPU,
+ * we indicate that this PMD will need to be reloaded if the task
+ * is rescheduled on the CPU it ran last on.
+ */
+ ctx->ctx_reload_pmds[0] |= 1UL << cnum;
+#endif
+ }
+ }
+
+ DPRINT(("pmd[%u]=0x%lx loaded=%d access_pmu=%d, hw_value=0x%lx ctx_pmd=0x%lx short_reset=0x%lx "
+ "long_reset=0x%lx notify=%c used_pmds=0x%lx reset_pmds=0x%lx reload_pmds=0x%lx all_pmds=0x%lx ovfl_regs=0x%lx\n",
+ cnum,
+ value,
+ is_loaded,
+ can_access_pmu,
+ hw_value,
+ ctx->ctx_pmds[cnum].val,
+ ctx->ctx_pmds[cnum].short_reset,
+ ctx->ctx_pmds[cnum].long_reset,
+ PMC_OVFL_NOTIFY(ctx, cnum) ? 'Y':'N',
+ ctx->ctx_used_pmds[0],
+ ctx->ctx_pmds[cnum].reset_pmds[0],
+ ctx->ctx_reload_pmds[0],
+ ctx->ctx_all_pmds[0],
+ ctx->ctx_ovfl_regs[0]));
+ }
+
+ /*
+ * make changes visible
+ */
+ if (can_access_pmu) ia64_srlz_d();
- DBprintk(("[%d] pmd[%u]: value=0x%lx hw_value=0x%lx soft_pmd=0x%lx short_reset=0x%lx "
- "long_reset=0x%lx hw_pmd=%lx notify=%c used_pmds=0x%lx reset_pmds=0x%lx\n",
- task->pid, cnum,
- value, hw_value,
- ctx->ctx_soft_pmds[cnum].val,
- ctx->ctx_soft_pmds[cnum].short_reset,
- ctx->ctx_soft_pmds[cnum].long_reset,
- ia64_get_pmd(cnum) & pmu_conf.ovfl_val,
- PMC_OVFL_NOTIFY(ctx, cnum) ? 'Y':'N',
- ctx->ctx_used_pmds[0],
- ctx->ctx_soft_pmds[cnum].reset_pmds[0]));
- }
- preempt_enable();
return 0;
abort_mission:
- preempt_enable();
-
/*
* for now, we have only one possibility for error
*/
- PFM_REG_RETFLAG_SET(tmp.reg_flags, PFM_REG_RETFL_EINVAL);
+ PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL);
/*
* we change the return value to EFAULT in case we cannot write register return code.
* The caller first must correct this error, then a resubmission of the request will
* eventually yield the EINVAL.
*/
- if (__put_user(tmp.reg_flags, &req->reg_flags)) ret = -EFAULT;
+ req->reg_flags = PFM_REG_RETFL_EINVAL;
- DBprintk(("[%d] pmc[%u]=0x%lx ret %d\n", task->pid, cnum, value, ret));
+ DPRINT(("pmd[%u]=0x%lx ret %d\n", cnum, value, ret));
return ret;
}
+/*
+ * By the way of PROTECT_CONTEXT(), interrupts are masked while we are in this function.
+ * Therefore we know, we do not have to worry about the PMU overflow interrupt. If an
+ * interrupt is delivered during the call, it will be kept pending until we leave, making
+ * it appears as if it had been generated at the UNPROTECT_CONTEXT(). At least we are
+ * guaranteed to return consistent data to the user, it may simply be old. It is not
+ * trivial to treat the overflow while inside the call because you may end up in
+ * some module sampling buffer code causing deadlocks.
+ */
static int
-pfm_read_pmds(struct task_struct *task, pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+pfm_read_pmds(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
{
- struct thread_struct *th = &task->thread;
- unsigned long val, lval;
+ struct thread_struct *thread = NULL;
+ unsigned long val = 0UL, lval ;
pfarg_reg_t *req = (pfarg_reg_t *)arg;
unsigned int cnum, reg_flags = 0;
- int i, ret = 0;
-
-#if __GNUC__ < 3
- int foo;
-#endif
+ int i, is_loaded, can_access_pmu = 0;
+ int ret = -EINVAL;
- if (!CTX_IS_ENABLED(ctx)) return -EINVAL;
+ if (CTX_IS_ZOMBIE(ctx)) return -EINVAL;
/*
- * XXX: MUST MAKE SURE WE DON"T HAVE ANY PENDING OVERFLOW BEFORE READING
- * This is required when the monitoring has been stoppped by user or kernel.
- * If it is still going on, then that's fine because we a re not guaranteed
- * to return an accurate value in this case.
+ * access is possible when loaded only for
+ * self-monitoring tasks or in UP mode
*/
+ is_loaded = CTX_IS_LOADED(ctx);
- /* XXX: ctx locking may be required here */
+ if (is_loaded) {
+ thread = &ctx->ctx_task->thread;
+ /*
+ * this can be true when not self-monitoring only in UP
+ */
+ can_access_pmu = GET_PMU_OWNER() == ctx->ctx_task? 1 : 0;
+
+ if (can_access_pmu) ia64_srlz_d();
+ /*
+ * In system wide and when the context is loaded, access can only happen
+ * when the caller is running on the CPU being monitored by the session.
+ * It does not have to be the owner (ctx_task) of the context per se.
+ */
+ if (ctx->ctx_fl_system && ctx->ctx_cpu != smp_processor_id()) {
+ DPRINT(("[%d] should be running on CPU%d\n", current->pid, ctx->ctx_cpu));
+ return -EBUSY;
+ }
+ }
+ DPRINT(("enter loaded=%d access_pmu=%d ctx_state=%d\n",
+ is_loaded,
+ can_access_pmu,
+ ctx->ctx_state));
- DBprintk(("ctx_last_cpu=%d for [%d]\n", atomic_read(&ctx->ctx_last_cpu), task->pid));
+ /*
+ * on both UP and SMP, we can only read the PMD from the hardware register when
+ * the task is the owner of the local PMU.
+ */
for (i = 0; i < count; i++, req++) {
- int me;
-#if __GNUC__ < 3
- foo = __get_user(cnum, &req->reg_num);
- if (foo) return -EFAULT;
- foo = __get_user(reg_flags, &req->reg_flags);
- if (foo) return -EFAULT;
-#else
- if (__get_user(cnum, &req->reg_num)) return -EFAULT;
- if (__get_user(reg_flags, &req->reg_flags)) return -EFAULT;
-#endif
- lval = 0UL;
- if (!PMD_IS_IMPL(cnum)) goto abort_mission;
+ lval = 0UL;
+ cnum = req->reg_num;
+ reg_flags = req->reg_flags;
+
+ if (!PMD_IS_IMPL(cnum)) goto error;
/*
* we can only read the register that we use. That includes
- * the one we explicitly initialize AND the one we want included
+ * the one we explicitely initialize AND the one we want included
* in the sampling buffer (smpl_regs).
*
* Having this restriction allows optimization in the ctxsw routine
* without compromising security (leaks)
*/
- if (!CTX_IS_USED_PMD(ctx, cnum)) goto abort_mission;
+ if (!CTX_IS_USED_PMD(ctx, cnum)) goto error;
/*
* If the task is not the current one, then we check if the
* PMU state is still in the local live register due to lazy ctxsw.
* If true, then we read directly from the registers.
*/
- me = get_cpu();
- if (atomic_read(&ctx->ctx_last_cpu) == me){
- ia64_srlz_d();
+ if (can_access_pmu){
val = ia64_get_pmd(cnum);
- DBprintk(("reading pmd[%u]=0x%lx from hw\n", cnum, val));
} else {
- val = th->pmd[cnum];
+ /*
+ * context has been saved
+ * if context is zombie, then task does not exist anymore.
+ * In this case, we use the full value saved in the context (pfm_flush_regs()).
+ */
+ val = CTX_IS_LOADED(ctx) ? thread->pmds[cnum] : 0UL;
}
-
if (PMD_IS_COUNTING(cnum)) {
/*
- * XXX: need to check for overflow
+ * XXX: need to check for overflow when loaded
*/
val &= pmu_conf.ovfl_val;
- val += ctx->ctx_soft_pmds[cnum].val;
+ val += ctx->ctx_pmds[cnum].val;
+
+ lval = ctx->ctx_pmds[cnum].lval;
+ }
+
+ /*
+ * execute read checker, if any
+ */
+ if (PMD_RD_FUNC(cnum)) {
+ unsigned long v = val;
+ ret = PMD_RD_FUNC(cnum)(ctx->ctx_task, ctx, cnum, &v, regs);
+ if (ret) goto error;
+ val = v;
+ ret = -EINVAL;
+ }
+
+ PFM_REG_RETFLAG_SET(reg_flags, 0);
+
+ DPRINT(("pmd[%u]=0x%lx loaded=%d access_pmu=%d ctx_state=%d\n",
+ cnum,
+ val,
+ is_loaded,
+ can_access_pmu,
+ ctx->ctx_state));
+
+ /*
+ * update register return value, abort all if problem during copy.
+ * we only modify the reg_flags field. no check mode is fine because
+ * access has been verified upfront in sys_perfmonctl().
+ */
+ req->reg_value = val;
+ req->reg_flags = reg_flags;
+ req->reg_last_reset_val = lval;
+ }
+
+ return 0;
+
+error:
+ PFM_REG_RETFLAG_SET(reg_flags, PFM_REG_RETFL_EINVAL);
+
+ req->reg_flags = PFM_REG_RETFL_EINVAL;
+
+ DPRINT(("error pmd[%u]=0x%lx\n", cnum, val));
+
+ return ret;
+}
+
+long
+pfm_mod_write_pmcs(struct task_struct *task, pfarg_reg_t *req, unsigned int nreq, struct pt_regs *regs)
+{
+ pfm_context_t *ctx;
+
+ if (task == NULL || req == NULL) return -EINVAL;
+
+ ctx = task->thread.pfm_context;
+
+ if (ctx == NULL) return -EINVAL;
+
+ /*
+ * for now limit to current task, which is enough when calling
+ * from overflow handler
+ */
+ if (task != current) return -EBUSY;
+
+ return pfm_write_pmcs(ctx, req, nreq, regs);
+}
+
+long
+pfm_mod_read_pmds(struct task_struct *task, pfarg_reg_t *req, unsigned int nreq, struct pt_regs *regs)
+{
+ pfm_context_t *ctx;
+
+ if (task == NULL || req == NULL) return -EINVAL;
+
+ //ctx = task->thread.pfm_context;
+ ctx = GET_PMU_CTX();
+
+ if (ctx == NULL) return -EINVAL;
+
+ /*
+ * for now limit to current task, which is enough when calling
+ * from overflow handler
+ */
+ if (task != current && ctx->ctx_fl_system == 0) return -EBUSY;
+
+ return pfm_read_pmds(ctx, req, nreq, regs);
+}
+
+long
+pfm_mod_fast_read_pmds(struct task_struct *task, unsigned long mask[4], unsigned long *addr, struct pt_regs *regs)
+{
+ pfm_context_t *ctx;
+ unsigned long m, val;
+ unsigned int j;
- lval = ctx->ctx_soft_pmds[cnum].lval;
- }
+ if (task == NULL || addr == NULL) return -EINVAL;
- /*
- * execute read checker, if any
- */
- if (PMD_RD_FUNC(cnum)) {
- unsigned long v = val;
- ret = PMD_RD_FUNC(cnum)(task, cnum, &v, regs);
- val = v;
- }
+ //ctx = task->thread.pfm_context;
+ ctx = GET_PMU_CTX();
- PFM_REG_RETFLAG_SET(reg_flags, ret);
+ if (ctx == NULL) return -EINVAL;
- put_cpu();
+ /*
+ * for now limit to current task, which is enough when calling
+ * from overflow handler
+ */
+ if (task != current && ctx->ctx_fl_system == 0) return -EBUSY;
- DBprintk(("read pmd[%u] ret=%d value=0x%lx pmc=0x%lx\n",
- cnum, ret, val, ia64_get_pmc(cnum)));
+ m = mask[0];
+ for (j=0; m; m >>=1, j++) {
- /*
- * update register return value, abort all if problem during copy.
- * we only modify the reg_flags field. no check mode is fine because
- * access has been verified upfront in sys_perfmonctl().
- */
- if (__put_user(cnum, &req->reg_num)) return -EFAULT;
- if (__put_user(val, &req->reg_value)) return -EFAULT;
- if (__put_user(reg_flags, &req->reg_flags)) return -EFAULT;
- if (__put_user(lval, &req->reg_last_reset_value)) return -EFAULT;
- }
+ if ((m & 0x1) == 0) continue;
- return 0;
+ if (!(PMD_IS_IMPL(j) && CTX_IS_USED_PMD(ctx, j)) ) return -EINVAL;
-abort_mission:
- PFM_REG_RETFLAG_SET(reg_flags, PFM_REG_RETFL_EINVAL);
- /*
- * XXX: if this fails, we stick with the original failure, flag not updated!
- */
- __put_user(reg_flags, &req->reg_flags);
+ if (PMD_IS_COUNTING(j)) {
+ val = pfm_read_soft_counter(ctx, j);
+ } else {
+ val = ia64_get_pmd(j);
+ }
- return -EINVAL;
+ *addr++ = val;
+
+ /* XXX: should call read checker routine? */
+ DPRINT(("single_read_pmd[%u]=0x%lx\n", j, val));
+ }
+ return 0;
}
-#ifdef PFM_PMU_USES_DBR
/*
* Only call this function when a process it trying to
* write the debug registers (reading is always allowed)
pfm_context_t *ctx = task->thread.pfm_context;
int ret = 0;
- DBprintk(("called for [%d]\n", task->pid));
+ if (pmu_conf.use_rr_dbregs == 0) return 0;
+
+ DPRINT(("called for [%d]\n", task->pid));
/*
* do it only once
else
pfm_sessions.pfs_ptrace_use_dbregs++;
- DBprintk(("ptrace_use_dbregs=%u sys_use_dbregs=%u by [%d] ret = %d\n",
- pfm_sessions.pfs_ptrace_use_dbregs,
- pfm_sessions.pfs_sys_use_dbregs,
+ DPRINT(("ptrace_use_dbregs=%u sys_use_dbregs=%u by [%d] ret = %d\n",
+ pfm_sessions.pfs_ptrace_use_dbregs,
+ pfm_sessions.pfs_sys_use_dbregs,
task->pid, ret));
UNLOCK_PFS();
{
int ret;
+ if (pmu_conf.use_rr_dbregs == 0) return 0;
+
LOCK_PFS();
if (pfm_sessions.pfs_ptrace_use_dbregs == 0) {
- printk(KERN_DEBUG "perfmon: invalid release for [%d] ptrace_use_dbregs=0\n",
- task->pid);
+ printk(KERN_ERR "perfmon: invalid release for [%d] ptrace_use_dbregs=0\n", task->pid);
ret = -1;
} else {
pfm_sessions.pfs_ptrace_use_dbregs--;
return ret;
}
-#else /* PFM_PMU_USES_DBR is true */
-/*
- * in case, the PMU does not use the debug registers, these two functions are nops.
- * The first function is called from arch/ia64/kernel/ptrace.c.
- * The second function is called from arch/ia64/kernel/process.c.
- */
-int
-pfm_use_debug_registers(struct task_struct *task)
-{
- return 0;
-}
-
-int
-pfm_release_debug_registers(struct task_struct *task)
-{
- return 0;
-}
-#endif /* PFM_PMU_USES_DBR */
static int
-pfm_restart(struct task_struct *task, pfm_context_t *ctx, void *arg, int count,
- struct pt_regs *regs)
+pfm_restart(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
{
- void *sem = &ctx->ctx_restart_sem;
+ struct task_struct *task;
+ pfm_buffer_fmt_t *fmt;
+ pfm_ovfl_ctrl_t rst_ctrl;
+ int is_loaded;
+ int ret = 0;
+
+ fmt = ctx->ctx_buf_fmt;
+ is_loaded = CTX_IS_LOADED(ctx);
+
+ if (is_loaded && CTX_HAS_SMPL(ctx) && fmt->fmt_restart_active) goto proceed;
+
+ /*
+ * restarting a terminated context is a nop
+ */
+ if (unlikely(CTX_IS_TERMINATED(ctx))) {
+ DPRINT(("context is terminated, nothing to do\n"));
+ return 0;
+ }
- /*
- * Cannot do anything before PMU is enabled
+
+ /*
+ * LOADED, UNLOADED, ZOMBIE
*/
- if (!CTX_IS_ENABLED(ctx)) return -EINVAL;
+ if (CTX_IS_MASKED(ctx) == 0) return -EBUSY;
+
+proceed:
+ /*
+ * In system wide and when the context is loaded, access can only happen
+ * when the caller is running on the CPU being monitored by the session.
+ * It does not have to be the owner (ctx_task) of the context per se.
+ */
+ if (ctx->ctx_fl_system && ctx->ctx_cpu != smp_processor_id()) {
+ DPRINT(("[%d] should be running on CPU%d\n", current->pid, ctx->ctx_cpu));
+ return -EBUSY;
+ }
+
+ task = PFM_CTX_TASK(ctx);
+
+ /* sanity check */
+ if (unlikely(task == NULL)) {
+ printk(KERN_ERR "perfmon: [%d] pfm_restart no task\n", current->pid);
+ return -EINVAL;
+ }
+ /*
+ * this test is always true in system wide mode
+ */
if (task == current) {
- DBprintk(("restarting self %d frozen=%d ovfl_regs=0x%lx\n",
- task->pid,
- ctx->ctx_fl_frozen,
+
+ fmt = ctx->ctx_buf_fmt;
+
+ DPRINT(("restarting self %d ovfl=0x%lx\n",
+ task->pid,
ctx->ctx_ovfl_regs[0]));
- preempt_disable();
- pfm_reset_regs(ctx, ctx->ctx_ovfl_regs, PFM_PMD_LONG_RESET);
+ if (CTX_HAS_SMPL(ctx)) {
- ctx->ctx_ovfl_regs[0] = 0UL;
+ prefetch(ctx->ctx_smpl_hdr);
- /*
- * We ignore block/don't block because we never block
- * for a self-monitoring process.
- */
- ctx->ctx_fl_frozen = 0;
+ rst_ctrl.stop_monitoring = 0;
+ rst_ctrl.reset_pmds = PFM_PMD_NO_RESET;
- if (CTX_HAS_SMPL(ctx)) {
- ctx->ctx_psb->psb_hdr->hdr_count = 0;
- ctx->ctx_psb->psb_index = 0;
+ if (is_loaded)
+ ret = pfm_buf_fmt_restart_active(fmt, task, &rst_ctrl, ctx->ctx_smpl_hdr, regs);
+ else
+ ret = pfm_buf_fmt_restart(fmt, task, &rst_ctrl, ctx->ctx_smpl_hdr, regs);
+
+
+ } else {
+ rst_ctrl.stop_monitoring = 0;
+ rst_ctrl.reset_pmds = PFM_PMD_LONG_RESET;
}
- /* simply unfreeze */
- pfm_unfreeze_pmu();
+ if (ret == 0) {
+ if (rst_ctrl.reset_pmds)
+ pfm_reset_regs(ctx, ctx->ctx_ovfl_regs, rst_ctrl.reset_pmds);
+
+ if (rst_ctrl.stop_monitoring == 0) {
+ DPRINT(("resuming monitoring for [%d]\n", task->pid));
- preempt_enable();
+ if (CTX_IS_MASKED(ctx)) pfm_restore_monitoring(task);
+ } else {
+ DPRINT(("keeping monitoring stopped for [%d]\n", task->pid));
+
+ // cannot use pfm_stop_monitoring(task, regs);
+ }
+ }
+ /*
+ * clear overflowed PMD mask to remove any stale information
+ */
+ ctx->ctx_ovfl_regs[0] = 0UL;
+
+ /*
+ * back to LOADED state
+ */
+ CTX_LOADED(ctx);
return 0;
- }
- /* restart on another task */
+ }
+ /* restart another task */
/*
* if blocking, then post the semaphore.
* if non-blocking, then we ensure that the task will go into
- * pfm_overflow_must_block() before returning to user mode.
- * We cannot explicitly reset another task, it MUST always
+ * pfm_handle_work() before returning to user mode.
+ * We cannot explicitely reset another task, it MUST always
* be done by the task itself. This works for system wide because
* the tool that is controlling the session is doing "self-monitoring".
*
*
*/
if (CTX_OVFL_NOBLOCK(ctx) == 0) {
- DBprintk(("unblocking %d \n", task->pid));
- up(sem);
+ DPRINT(("unblocking [%d] \n", task->pid));
+ up(&ctx->ctx_restart_sem);
} else {
- struct thread_info *info = (struct thread_info *) ((char *) task + IA64_TASK_SIZE);
- task->thread.pfm_ovfl_block_reset = 1;
+ DPRINT(("[%d] armed exit trap\n", task->pid));
+
ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_RESET;
- set_bit(TIF_NOTIFY_RESUME, &info->flags);
+
+
+ PFM_SET_WORK_PENDING(task, 1);
+
+ pfm_set_task_notify(task);
+
+ /*
+ * XXX: send reschedule if task runs on another CPU
+ */
}
-#if 0
+ return 0;
+}
+
+static int
+pfm_debug(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ unsigned int m = *(unsigned int *)arg;
+
+ pfm_sysctl.debug = m == 0 ? 0 : 1;
+
+ pfm_debug_var = pfm_sysctl.debug;
+
+ printk(KERN_ERR "perfmon debugging %s (timing reset)\n", pfm_sysctl.debug ? "on" : "off");
+
+
+ if (m==0) {
+ memset(pfm_stats, 0, sizeof(pfm_stats));
+ for(m=0; m < NR_CPUS; m++) pfm_stats[m].pfm_ovfl_intr_cycles_min = ~0UL;
+ }
+
+ return 0;
+}
+
+
+static int
+pfm_write_ibr_dbr(int mode, pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ struct thread_struct *thread = NULL;
+ pfarg_dbreg_t *req = (pfarg_dbreg_t *)arg;
+ dbreg_t dbreg;
+ unsigned int rnum;
+ int first_time;
+ int ret = 0;
+ int i, can_access_pmu = 0, is_loaded;
+
+ if (pmu_conf.use_rr_dbregs == 0) return -EINVAL;
+
+ if (CTX_IS_DEAD(ctx)) return -EINVAL;
+
+ is_loaded = CTX_IS_LOADED(ctx);
+ /*
+ * on both UP and SMP, we can only write to the PMC when the task is
+ * the owner of the local PMU.
+ */
+ if (is_loaded) {
+ thread = &ctx->ctx_task->thread;
+ can_access_pmu = GET_PMU_OWNER() == ctx->ctx_task ? 1 : 0;
+ /*
+ * In system wide and when the context is loaded, access can only happen
+ * when the caller is running on the CPU being monitored by the session.
+ * It does not have to be the owner (ctx_task) of the context per se.
+ */
+ if (ctx->ctx_fl_system && ctx->ctx_cpu != smp_processor_id()) {
+ DPRINT(("[%d] should be running on CPU%d\n", current->pid, ctx->ctx_cpu));
+ return -EBUSY;
+ }
+ }
+
/*
- * in case of non blocking mode, then it's just a matter of
- * of reseting the sampling buffer (if any) index. The PMU
- * is already active.
+ * we do not need to check for ipsr.db because we do clear ibr.x, dbr.r, and dbr.w
+ * ensuring that no real breakpoint can be installed via this call.
+ *
+ * IMPORTANT: regs can be NULL in this function
*/
+ first_time = ctx->ctx_fl_using_dbreg == 0;
+
/*
- * must reset the header count first
+ * don't bother if we are loaded and task is being debugged
*/
- if (CTX_HAS_SMPL(ctx)) {
- DBprintk(("resetting sampling indexes for %d \n", task->pid));
- ctx->ctx_psb->psb_hdr->hdr_count = 0;
- ctx->ctx_psb->psb_index = 0;
+ if (is_loaded && (thread->flags & IA64_THREAD_DBG_VALID) != 0) {
+ DPRINT(("debug registers already in use for [%d]\n", ctx->ctx_task->pid));
+ return -EBUSY;
}
-#endif
+
+ /*
+ * check for debug registers in system wide mode
+ *
+ * We make the reservation even when context is not loaded
+ * to make sure we get our slot. Note that the PFM_LOAD_CONTEXT
+ * may still fail if the task has DBG_VALID set.
+ */
+ LOCK_PFS();
+
+ if (first_time && ctx->ctx_fl_system) {
+ if (pfm_sessions.pfs_ptrace_use_dbregs)
+ ret = -EBUSY;
+ else
+ pfm_sessions.pfs_sys_use_dbregs++;
+ }
+
+ UNLOCK_PFS();
+
+ if (ret != 0) return ret;
+
+ /*
+ * mark ourself as user of the debug registers for
+ * perfmon purposes.
+ */
+ ctx->ctx_fl_using_dbreg = 1;
+
+ /*
+ * clear hardware registers to make sure we don't
+ * pick up stale state.
+ *
+ * for a system wide session, we do not use
+ * thread.dbr, thread.ibr because this process
+ * never leaves the current CPU and the state
+ * is shared by all processes running on it
+ */
+ if (first_time && can_access_pmu) {
+ DPRINT(("[%d] clearing ibrs, dbrs\n", ctx->ctx_task->pid));
+ for (i=0; i < pmu_conf.num_ibrs; i++) {
+ ia64_set_ibr(i, 0UL);
+ ia64_srlz_i();
+ }
+ ia64_srlz_i();
+ for (i=0; i < pmu_conf.num_dbrs; i++) {
+ ia64_set_dbr(i, 0UL);
+ ia64_srlz_d();
+ }
+ ia64_srlz_d();
+ }
+
+ /*
+ * Now install the values into the registers
+ */
+ for (i = 0; i < count; i++, req++) {
+
+ rnum = req->dbreg_num;
+ dbreg.val = req->dbreg_value;
+
+ ret = -EINVAL;
+
+ if ((mode == PFM_CODE_RR && !IBR_IS_IMPL(rnum)) || ((mode == PFM_DATA_RR) && !DBR_IS_IMPL(rnum))) {
+ DPRINT(("invalid register %u val=0x%lx mode=%d i=%d count=%d\n",
+ rnum, dbreg.val, mode, i, count));
+
+ goto abort_mission;
+ }
+
+ /*
+ * make sure we do not install enabled breakpoint
+ */
+ if (rnum & 0x1) {
+ if (mode == PFM_CODE_RR)
+ dbreg.ibr.ibr_x = 0;
+ else
+ dbreg.dbr.dbr_r = dbreg.dbr.dbr_w = 0;
+ }
+
+ PFM_REG_RETFLAG_SET(req->dbreg_flags, 0);
+
+ /*
+ * Debug registers, just like PMC, can only be modified
+ * by a kernel call. Moreover, perfmon() access to those
+ * registers are centralized in this routine. The hardware
+ * does not modify the value of these registers, therefore,
+ * if we save them as they are written, we can avoid having
+ * to save them on context switch out. This is made possible
+ * by the fact that when perfmon uses debug registers, ptrace()
+ * won't be able to modify them concurrently.
+ */
+ if (mode == PFM_CODE_RR) {
+ CTX_USED_IBR(ctx, rnum);
+
+ if (can_access_pmu) ia64_set_ibr(rnum, dbreg.val);
+
+ ctx->ctx_ibrs[rnum] = dbreg.val;
+
+ DPRINT(("write ibr%u=0x%lx used_ibrs=0x%x is_loaded=%d access_pmu=%d\n",
+ rnum, dbreg.val, ctx->ctx_used_ibrs[0], is_loaded, can_access_pmu));
+ } else {
+ CTX_USED_DBR(ctx, rnum);
+
+ if (can_access_pmu) ia64_set_dbr(rnum, dbreg.val);
+
+ ctx->ctx_dbrs[rnum] = dbreg.val;
+
+ DPRINT(("write dbr%u=0x%lx used_dbrs=0x%x is_loaded=%d access_pmu=%d\n",
+ rnum, dbreg.val, ctx->ctx_used_dbrs[0], is_loaded, can_access_pmu));
+ }
+ }
+
+ return 0;
+
+abort_mission:
+ /*
+ * in case it was our first attempt, we undo the global modifications
+ */
+ if (first_time) {
+ LOCK_PFS();
+ if (ctx->ctx_fl_system) {
+ pfm_sessions.pfs_sys_use_dbregs--;
+ }
+ UNLOCK_PFS();
+ ctx->ctx_fl_using_dbreg = 0;
+ }
+ /*
+ * install error return flag
+ */
+ PFM_REG_RETFLAG_SET(req->dbreg_flags, PFM_REG_RETFL_EINVAL);
+
+ return ret;
+}
+
+static int
+pfm_write_ibrs(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ return pfm_write_ibr_dbr(PFM_CODE_RR, ctx, arg, count, regs);
+}
+
+static int
+pfm_write_dbrs(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ return pfm_write_ibr_dbr(PFM_DATA_RR, ctx, arg, count, regs);
+}
+
+static int
+pfm_get_features(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ pfarg_features_t *req = (pfarg_features_t *)arg;
+
+ req->ft_version = PFM_VERSION;
return 0;
}
static int
-pfm_stop(struct task_struct *task, pfm_context_t *ctx, void *arg, int count,
- struct pt_regs *regs)
+pfm_stop(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
{
- /* we don't quite support this right now */
- if (task != current) return -EINVAL;
+ struct pt_regs *tregs;
- /*
- * Cannot do anything before PMU is enabled
- */
- if (!CTX_IS_ENABLED(ctx)) return -EINVAL;
- DBprintk(("[%d] fl_system=%d owner=%p current=%p\n",
- current->pid,
- ctx->ctx_fl_system, PMU_OWNER(),
- current));
+ if (CTX_IS_LOADED(ctx) == 0 && CTX_IS_MASKED(ctx) == 0) return -EINVAL;
+
+ /*
+ * In system wide and when the context is loaded, access can only happen
+ * when the caller is running on the CPU being monitored by the session.
+ * It does not have to be the owner (ctx_task) of the context per se.
+ */
+ if (ctx->ctx_fl_system && ctx->ctx_cpu != smp_processor_id()) {
+ DPRINT(("[%d] should be running on CPU%d\n", current->pid, ctx->ctx_cpu));
+ return -EBUSY;
+ }
- preempt_disable();
- /* simply stop monitoring but not the PMU */
+ /*
+ * in system mode, we need to update the PMU directly
+ * and the user level state of the caller, which may not
+ * necessarily be the creator of the context.
+ */
if (ctx->ctx_fl_system) {
-
- /* disable dcr pp */
+ /*
+ * Update local PMU first
+ *
+ * disable dcr pp
+ */
ia64_set_dcr(ia64_get_dcr() & ~IA64_DCR_PP);
-
- /* stop monitoring */
- pfm_clear_psr_pp();
-
ia64_srlz_i();
+ /*
+ * update local cpuinfo
+ */
PFM_CPUINFO_CLEAR(PFM_CPUINFO_DCR_PP);
+ /*
+ * stop monitoring, does srlz.i
+ */
+ pfm_clear_psr_pp();
+
+ /*
+ * stop monitoring in the caller
+ */
ia64_psr(regs)->pp = 0;
- } else {
+ return 0;
+ }
+ /*
+ * per-task mode
+ */
- /* stop monitoring */
+ if (ctx->ctx_task == current) {
+ /* stop monitoring at kernel level */
pfm_clear_psr_up();
- ia64_srlz_i();
+ /*
+ * stop monitoring at the user level
+ */
+ ia64_psr(regs)->up = 0;
+ } else {
+ tregs = ia64_task_regs(ctx->ctx_task);
+
+ /*
+ * stop monitoring at the user level
+ */
+ ia64_psr(tregs)->up = 0;
/*
- * clear user level psr.up
+ * monitoring disabled in kernel at next reschedule
*/
- ia64_psr(regs)->up = 0;
+ ctx->ctx_saved_psr &= ~IA64_PSR_UP;
+ printk("pfm_stop: current [%d] task=[%d]\n", current->pid, ctx->ctx_task->pid);
}
- preempt_enable();
return 0;
}
+
static int
-pfm_disable(struct task_struct *task, pfm_context_t *ctx, void *arg, int count,
- struct pt_regs *regs)
-{
- /* we don't quite support this right now */
- if (task != current) return -EINVAL;
+pfm_start(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ struct pt_regs *tregs;
- if (!CTX_IS_ENABLED(ctx)) return -EINVAL;
+ if (CTX_IS_LOADED(ctx) == 0) return -EINVAL;
- preempt_disable();
/*
- * stop monitoring, freeze PMU, and save state in context
- * this call will clear IA64_THREAD_PM_VALID for per-task sessions.
- */
- pfm_flush_regs(task);
-
- if (ctx->ctx_fl_system) {
- ia64_psr(regs)->pp = 0;
- } else {
- ia64_psr(regs)->up = 0;
+ * In system wide and when the context is loaded, access can only happen
+ * when the caller is running on the CPU being monitored by the session.
+ * It does not have to be the owner (ctx_task) of the context per se.
+ */
+ if (ctx->ctx_fl_system && ctx->ctx_cpu != smp_processor_id()) {
+ DPRINT(("[%d] should be running on CPU%d\n", current->pid, ctx->ctx_cpu));
+ return -EBUSY;
}
- /*
- * goes back to default behavior: no user level control
- * no need to change live psr.sp because useless at the kernel level
+
+ /*
+ * in system mode, we need to update the PMU directly
+ * and the user level state of the caller, which may not
+ * necessarily be the creator of the context.
*/
- ia64_psr(regs)->sp = 1;
+ if (ctx->ctx_fl_system) {
- DBprintk(("enabling psr.sp for [%d]\n", current->pid));
+ /*
+ * set user level psr.pp for the caller
+ */
+ ia64_psr(regs)->pp = 1;
- ctx->ctx_flags.state = PFM_CTX_DISABLED;
- preempt_enable();
+ /*
+ * now update the local PMU and cpuinfo
+ */
+ PFM_CPUINFO_SET(PFM_CPUINFO_DCR_PP);
- return 0;
-}
+ /*
+ * start monitoring at kernel level
+ */
+ pfm_set_psr_pp();
-static int
-pfm_context_destroy(struct task_struct *task, pfm_context_t *ctx, void *arg, int count,
- struct pt_regs *regs)
-{
- /* we don't quite support this right now */
- if (task != current) return -EINVAL;
+ /* enable dcr pp */
+ ia64_set_dcr(ia64_get_dcr()|IA64_DCR_PP);
+ ia64_srlz_i();
- /*
- * if context was never enabled, then there is not much
- * to do
- */
- if (!CTX_IS_ENABLED(ctx)) goto skipped_stop;
+ return 0;
+ }
/*
- * Disable context: stop monitoring, flush regs to software state (useless here),
- * and freeze PMU
- *
- * The IA64_THREAD_PM_VALID is cleared by pfm_flush_regs() called from pfm_disable()
+ * per-process mode
*/
- pfm_disable(task, ctx, arg, count, regs);
- if (ctx->ctx_fl_system) {
- ia64_psr(regs)->pp = 0;
- } else {
- ia64_psr(regs)->up = 0;
- }
+ if (ctx->ctx_task == current) {
-skipped_stop:
- /*
- * remove sampling buffer mapping, if any
- */
- if (ctx->ctx_smpl_vaddr) {
- pfm_remove_smpl_mapping(task);
- ctx->ctx_smpl_vaddr = 0UL;
- }
- /* now free context and related state */
- pfm_context_exit(task);
+ /* start monitoring at kernel level */
+ pfm_set_psr_up();
- return 0;
-}
+ /*
+ * activate monitoring at user level
+ */
+ ia64_psr(regs)->up = 1;
-/*
- * does nothing at the moment
- */
-static int
-pfm_context_unprotect(struct task_struct *task, pfm_context_t *ctx, void *arg, int count,
- struct pt_regs *regs)
-{
- return 0;
-}
+ } else {
+ tregs = ia64_task_regs(ctx->ctx_task);
-static int
-pfm_protect_context(struct task_struct *task, pfm_context_t *ctx, void *arg, int count,
- struct pt_regs *regs)
-{
- DBprintk(("context from [%d] is protected\n", task->pid));
- /*
- * from now on, only the creator of the context has access to it
- */
- ctx->ctx_fl_protected = 1;
+ /*
+ * start monitoring at the kernel level the next
+ * time the task is scheduled
+ */
+ ctx->ctx_saved_psr |= IA64_PSR_UP;
- /*
- * reinforce secure monitoring: cannot toggle psr.up
- */
- if (ctx->ctx_fl_unsecure == 0) ia64_psr(regs)->sp = 1;
+ /*
+ * activate monitoring at user level
+ */
+ ia64_psr(tregs)->up = 1;
+ }
return 0;
}
static int
-pfm_debug(struct task_struct *task, pfm_context_t *ctx, void *arg, int count,
- struct pt_regs *regs)
+pfm_get_pmc_reset(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
{
- unsigned int mode = *(unsigned int *)arg;
+ pfarg_reg_t *req = (pfarg_reg_t *)arg;
+ unsigned int cnum;
+ int i;
+ int ret = -EINVAL;
- pfm_sysctl.debug = mode == 0 ? 0 : 1;
+ for (i = 0; i < count; i++, req++) {
- printk(KERN_INFO "perfmon debugging %s\n", pfm_sysctl.debug ? "on" : "off");
+ cnum = req->reg_num;
- return 0;
-}
+ if (!PMC_IS_IMPL(cnum)) goto abort_mission;
-#ifdef PFM_PMU_USES_DBR
+ req->reg_value = PMC_DFL_VAL(cnum);
-typedef struct {
- unsigned long ibr_mask:56;
- unsigned long ibr_plm:4;
- unsigned long ibr_ig:3;
- unsigned long ibr_x:1;
-} ibr_mask_reg_t;
+ PFM_REG_RETFLAG_SET(req->reg_flags, 0);
-typedef struct {
- unsigned long dbr_mask:56;
- unsigned long dbr_plm:4;
- unsigned long dbr_ig:2;
- unsigned long dbr_w:1;
- unsigned long dbr_r:1;
-} dbr_mask_reg_t;
+ DPRINT(("pmc_reset_val pmc[%u]=0x%lx\n", cnum, req->reg_value));
+ }
+ return 0;
-typedef union {
- unsigned long val;
- ibr_mask_reg_t ibr;
- dbr_mask_reg_t dbr;
-} dbreg_t;
+abort_mission:
+ PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL);
+ return ret;
+}
static int
-pfm_write_ibr_dbr(int mode, struct task_struct *task, void *arg, int count, struct pt_regs *regs)
+pfm_context_load(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
{
- struct thread_struct *thread = &task->thread;
- pfm_context_t *ctx = task->thread.pfm_context;
- pfarg_dbreg_t tmp, *req = (pfarg_dbreg_t *)arg;
- dbreg_t dbreg;
- unsigned int rnum;
- int first_time;
- int i, ret = 0;
+ struct task_struct *task;
+ struct thread_struct *thread;
+ struct pfm_context_t *old;
+#ifndef CONFIG_SMP
+ struct task_struct *owner_task = NULL;
+#endif
+ pfarg_load_t *req = (pfarg_load_t *)arg;
+ unsigned long *pmcs_source, *pmds_source;
+ int the_cpu;
+ int ret = 0;
/*
- * we do not need to check for ipsr.db because we do clear ibr.x, dbr.r, and dbr.w
- * ensuring that no real breakpoint can be installed via this call.
+ * can only load from unloaded or terminated state
*/
+ if (CTX_IS_UNLOADED(ctx) == 0 && CTX_IS_TERMINATED(ctx) == 0) {
+ DPRINT(("[%d] cannot load to [%d], invalid ctx_state=%d\n",
+ current->pid,
+ req->load_pid,
+ ctx->ctx_state));
+ return -EINVAL;
+ }
- first_time = ctx->ctx_fl_using_dbreg == 0;
+ DPRINT(("load_pid [%d]\n", req->load_pid));
+
+ if (CTX_OVFL_NOBLOCK(ctx) == 0 && req->load_pid == current->pid) {
+ DPRINT(("cannot use blocking mode on self for [%d]\n", current->pid));
+ return -EINVAL;
+ }
+
+ ret = pfm_get_task(ctx, req->load_pid, &task);
+ if (ret) {
+ DPRINT(("load_pid [%d] get_task=%d\n", req->load_pid, ret));
+ return ret;
+ }
+
+ ret = -EINVAL;
/*
- * check for debug registers in system wide mode
- *
+ * system wide is self monitoring only
*/
- LOCK_PFS();
- if (ctx->ctx_fl_system && first_time) {
- if (pfm_sessions.pfs_ptrace_use_dbregs)
- ret = -EBUSY;
- else
- pfm_sessions.pfs_sys_use_dbregs++;
+ if (ctx->ctx_fl_system && task != current) {
+ DPRINT(("system wide is self monitoring only current=%d load_pid=%d\n",
+ current->pid,
+ req->load_pid));
+ goto error;
}
- UNLOCK_PFS();
- if (ret != 0) return ret;
+ thread = &task->thread;
- if (ctx->ctx_fl_system) {
- /* we mark ourselves as owner of the debug registers */
- ctx->ctx_fl_using_dbreg = 1;
- DBprintk(("system-wide setting fl_using_dbreg for [%d]\n", task->pid));
- } else if (first_time) {
- ret= -EBUSY;
- if ((thread->flags & IA64_THREAD_DBG_VALID) != 0) {
- DBprintk(("debug registers already in use for [%d]\n", task->pid));
- goto abort_mission;
- }
- /* we mark ourselves as owner of the debug registers */
- ctx->ctx_fl_using_dbreg = 1;
-
- DBprintk(("setting fl_using_dbreg for [%d]\n", task->pid));
- /*
- * Given debug registers cannot be used for both debugging
- * and performance monitoring at the same time, we reuse
- * the storage area to save and restore the registers on ctxsw.
- */
- memset(task->thread.dbr, 0, sizeof(task->thread.dbr));
- memset(task->thread.ibr, 0, sizeof(task->thread.ibr));
- }
+ ret = -EBUSY;
- if (first_time) {
- DBprintk(("[%d] clearing ibrs,dbrs\n", task->pid));
- /*
- * clear hardware registers to make sure we don't
- * pick up stale state.
- *
- * for a system wide session, we do not use
- * thread.dbr, thread.ibr because this process
- * never leaves the current CPU and the state
- * is shared by all processes running on it
- */
- for (i=0; i < (int) pmu_conf.num_ibrs; i++) {
- ia64_set_ibr(i, 0UL);
- }
- ia64_srlz_i();
- for (i=0; i < (int) pmu_conf.num_dbrs; i++) {
- ia64_set_dbr(i, 0UL);
- }
- ia64_srlz_d();
+ /*
+ * cannot load a context which is using range restrictions,
+ * into a task that is being debugged.
+ */
+ if (ctx->ctx_fl_using_dbreg && (thread->flags & IA64_THREAD_DBG_VALID)) {
+ DPRINT(("load_pid [%d] task is debugged, cannot load range restrictions\n", req->load_pid));
+ goto error;
}
- ret = -EFAULT;
+ /*
+ * SMP system-wide monitoring implies self-monitoring.
+ *
+ * The programming model expects the task to
+ * be pinned on a CPU throughout the session.
+ * Here we take note of the current CPU at the
+ * time the context is loaded. No call from
+ * another CPU will be allowed.
+ *
+ * The pinning via shed_setaffinity()
+ * must be done by the calling task prior
+ * to this call.
+ *
+ * systemwide: keep track of CPU this session is supposed to run on
+ */
+ the_cpu = ctx->ctx_cpu = smp_processor_id();
/*
- * Now install the values into the registers
+ * now reserve the session
*/
- for (i = 0; i < count; i++, req++) {
-
- if (__copy_from_user(&tmp, req, sizeof(tmp))) goto abort_mission;
-
- rnum = tmp.dbreg_num;
- dbreg.val = tmp.dbreg_value;
-
- ret = -EINVAL;
+ ret = pfm_reserve_session(current, ctx->ctx_fl_system, the_cpu);
+ if (ret) goto error;
- if ((mode == 0 && !IBR_IS_IMPL(rnum)) || ((mode == 1) && !DBR_IS_IMPL(rnum))) {
- DBprintk(("invalid register %u val=0x%lx mode=%d i=%d count=%d\n",
- rnum, dbreg.val, mode, i, count));
+ ret = -EBUSY;
+ /*
+ * task is necessarily stopped at this point.
+ *
+ * If the previous context was zombie, then it got removed in
+ * pfm_save_regs(). Therefore we should not see it here.
+ * If we see a context, then this is an active context
+ *
+ * XXX: needs to be atomic
+ */
+ DPRINT(("[%d] before cmpxchg() old_ctx=%p new_ctx=%p\n",
+ current->pid,
+ thread->pfm_context, ctx));
- goto abort_mission;
- }
+ old = ia64_cmpxchg("acq", &thread->pfm_context, NULL, ctx, sizeof(pfm_context_t *));
+ if (old != NULL) {
+ DPRINT(("load_pid [%d] already has a context\n", req->load_pid));
+ goto error_unres;
+ }
- /*
- * make sure we do not install enabled breakpoint
- */
- if (rnum & 0x1) {
- if (mode == 0)
- dbreg.ibr.ibr_x = 0;
- else
- dbreg.dbr.dbr_r = dbreg.dbr.dbr_w = 0;
- }
+ pfm_reset_msgq(ctx);
- /*
- * clear return flags and copy back to user
- *
- * XXX: fix once EAGAIN is implemented
- */
- ret = -EFAULT;
+ CTX_LOADED(ctx);
- PFM_REG_RETFLAG_SET(tmp.dbreg_flags, 0);
+ /*
+ * link context to task
+ */
+ ctx->ctx_task = task;
- if (__copy_to_user(req, &tmp, sizeof(tmp))) goto abort_mission;
+ if (ctx->ctx_fl_system) {
/*
- * Debug registers, just like PMC, can only be modified
- * by a kernel call. Moreover, perfmon() access to those
- * registers are centralized in this routine. The hardware
- * does not modify the value of these registers, therefore,
- * if we save them as they are written, we can avoid having
- * to save them on context switch out. This is made possible
- * by the fact that when perfmon uses debug registers, ptrace()
- * won't be able to modify them concurrently.
+ * we load as stopped
*/
- if (mode == 0) {
- CTX_USED_IBR(ctx, rnum);
+ PFM_CPUINFO_SET(PFM_CPUINFO_SYST_WIDE);
+ PFM_CPUINFO_CLEAR(PFM_CPUINFO_DCR_PP);
- ia64_set_ibr(rnum, dbreg.val);
- ia64_srlz_i();
+ if (ctx->ctx_fl_excl_idle) PFM_CPUINFO_SET(PFM_CPUINFO_EXCL_IDLE);
+ } else {
+ thread->flags |= IA64_THREAD_PM_VALID;
+ }
- thread->ibr[rnum] = dbreg.val;
+ /*
+ * propagate into thread-state
+ */
+ pfm_copy_pmds(task, ctx);
+ pfm_copy_pmcs(task, ctx);
- DBprintk(("write ibr%u=0x%lx used_ibrs=0x%lx\n", rnum, dbreg.val, ctx->ctx_used_ibrs[0]));
- } else {
- CTX_USED_DBR(ctx, rnum);
+ pmcs_source = thread->pmcs;
+ pmds_source = thread->pmds;
- ia64_set_dbr(rnum, dbreg.val);
- ia64_srlz_d();
+ /*
+ * always the case for system-wide
+ */
+ if (task == current) {
- thread->dbr[rnum] = dbreg.val;
+ if (ctx->ctx_fl_system == 0) {
- DBprintk(("write dbr%u=0x%lx used_dbrs=0x%lx\n", rnum, dbreg.val, ctx->ctx_used_dbrs[0]));
+ /* allow user level control */
+ ia64_psr(regs)->sp = 0;
+ DPRINT(("clearing psr.sp for [%d]\n", task->pid));
+
+ SET_LAST_CPU(ctx, smp_processor_id());
+ INC_ACTIVATION();
+ SET_ACTIVATION(ctx);
+#ifndef CONFIG_SMP
+ /*
+ * push the other task out, if any
+ */
+ owner_task = GET_PMU_OWNER();
+ if (owner_task) pfm_lazy_save_regs(owner_task);
+#endif
}
- }
+ /*
+ * load all PMD from ctx to PMU (as opposed to thread state)
+ * restore all PMC from ctx to PMU
+ */
+ pfm_restore_pmds(pmds_source, ctx->ctx_all_pmds[0]);
+ pfm_restore_pmcs(pmcs_source, ctx->ctx_all_pmcs[0]);
- return 0;
+ ctx->ctx_reload_pmcs[0] = 0UL;
+ ctx->ctx_reload_pmds[0] = 0UL;
-abort_mission:
- /*
- * in case it was our first attempt, we undo the global modifications
- */
- if (first_time) {
- LOCK_PFS();
- if (ctx->ctx_fl_system) {
- pfm_sessions.pfs_sys_use_dbregs--;
+ /*
+ * guaranteed safe by earlier check against DBG_VALID
+ */
+ if (ctx->ctx_fl_using_dbreg) {
+ pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf.num_ibrs);
+ pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf.num_dbrs);
}
- UNLOCK_PFS();
- ctx->ctx_fl_using_dbreg = 0;
- }
- /*
- * install error return flag
- */
- if (ret != -EFAULT) {
/*
- * XXX: for now we can only come here on EINVAL
+ * set new ownership
*/
- PFM_REG_RETFLAG_SET(tmp.dbreg_flags, PFM_REG_RETFL_EINVAL);
- if (__put_user(tmp.dbreg_flags, &req->dbreg_flags)) ret = -EFAULT;
- }
- return ret;
-}
+ SET_PMU_OWNER(task, ctx);
-static int
-pfm_write_ibrs(struct task_struct *task, pfm_context_t *ctx, void *arg, int count,
- struct pt_regs *regs)
-{
- /* we don't quite support this right now */
- if (task != current) return -EINVAL;
+ DPRINT(("context loaded on PMU for [%d]\n", task->pid));
+ } else {
+ /*
+ * when not current, task MUST be stopped, so this is safe
+ */
+ regs = ia64_task_regs(task);
- if (!CTX_IS_ENABLED(ctx)) return -EINVAL;
+ /* force a full reload */
+ ctx->ctx_last_activation = PFM_INVALID_ACTIVATION;
+ SET_LAST_CPU(ctx, -1);
- return pfm_write_ibr_dbr(0, task, arg, count, regs);
-}
+ /* initial saved psr (stopped) */
+ ctx->ctx_saved_psr = pfm_get_psr() & ~(IA64_PSR_PP|IA64_PSR_UP);
+ ia64_psr(regs)->up = ia64_psr(regs)->pp = 0;
-static int
-pfm_write_dbrs(struct task_struct *task, pfm_context_t *ctx, void *arg, int count,
- struct pt_regs *regs)
-{
- /* we don't quite support this right now */
- if (task != current) return -EINVAL;
+ if (ctx->ctx_fl_unsecure) {
+ ia64_psr(regs)->sp = 0;
+ DPRINT(("context unsecured for [%d]\n", task->pid));
+ }
+ }
+
+ ret = 0;
- if (!CTX_IS_ENABLED(ctx)) return -EINVAL;
+error_unres:
+ if (ret) pfm_unreserve_session(ctx, ctx->ctx_fl_system, the_cpu);
+error:
+ /*
+ * release task, there is now a link with the context
+ */
+ if (ctx->ctx_fl_system == 0 && task != current) pfm_put_task(task);
- return pfm_write_ibr_dbr(1, task, arg, count, regs);
+ return ret;
}
-#endif /* PFM_PMU_USES_DBR */
+/*
+ * in this function, we do not need to increase the use count
+ * for the task via get_task_struct(), because we hold the
+ * context lock. If the task were to disappear while having
+ * a context attached, it would go through pfm_exit_thread()
+ * which also grabs the context lock and would therefore be blocked
+ * until we are here.
+ */
+static void pfm_flush_pmds(struct task_struct *, pfm_context_t *ctx);
static int
-pfm_get_features(struct task_struct *task, pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+pfm_context_unload(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
{
- pfarg_features_t tmp;
-
- memset(&tmp, 0, sizeof(tmp));
-
- tmp.ft_version = PFM_VERSION;
- tmp.ft_smpl_version = PFM_SMPL_VERSION;
-
- if (__copy_to_user(arg, &tmp, sizeof(tmp))) return -EFAULT;
-
- return 0;
-}
+ struct task_struct *task = ctx->ctx_task;
+ struct pt_regs *tregs;
-static int
-pfm_start(struct task_struct *task, pfm_context_t *ctx, void *arg, int count,
- struct pt_regs *regs)
-{
- /* we don't quite support this right now */
- if (task != current) return -EINVAL;
+ DPRINT(("ctx_state=%d task [%d]\n", ctx->ctx_state, task ? task->pid : -1));
- /*
- * Cannot do anything before PMU is enabled
+ /*
+ * unload only when necessary
*/
- if (!CTX_IS_ENABLED(ctx)) return -EINVAL;
-
- DBprintk(("[%d] fl_system=%d owner=%p current=%p\n",
- current->pid,
- ctx->ctx_fl_system, PMU_OWNER(),
- current));
+ if (CTX_IS_TERMINATED(ctx) || CTX_IS_UNLOADED(ctx)) {
+ DPRINT(("[%d] ctx_state=%d, nothing to do\n", current->pid, ctx->ctx_state));
+ return 0;
+ }
- if (PMU_OWNER() != task) {
- printk(KERN_DEBUG "perfmon: pfm_start task [%d] not pmu owner\n", task->pid);
- return -EINVAL;
+ /*
+ * In system wide and when the context is loaded, access can only happen
+ * when the caller is running on the CPU being monitored by the session.
+ * It does not have to be the owner (ctx_task) of the context per se.
+ */
+ if (ctx->ctx_fl_system && ctx->ctx_cpu != smp_processor_id()) {
+ DPRINT(("[%d] should be running on CPU%d\n", current->pid, ctx->ctx_cpu));
+ return -EBUSY;
}
- preempt_disable();
- if (ctx->ctx_fl_system) {
-
- PFM_CPUINFO_SET(PFM_CPUINFO_DCR_PP);
+ /*
+ * clear psr and dcr bits
+ */
+ pfm_stop(ctx, NULL, 0, regs);
- /* set user level psr.pp */
- ia64_psr(regs)->pp = 1;
+ CTX_UNLOADED(ctx);
- /* start monitoring at kernel level */
- pfm_set_psr_pp();
+ /*
+ * in system mode, we need to update the PMU directly
+ * and the user level state of the caller, which may not
+ * necessarily be the creator of the context.
+ */
+ if (ctx->ctx_fl_system) {
- /* enable dcr pp */
- ia64_set_dcr(ia64_get_dcr()|IA64_DCR_PP);
+ /*
+ * Update cpuinfo
+ *
+ * local PMU is taken care of in pfm_stop()
+ */
+ PFM_CPUINFO_CLEAR(PFM_CPUINFO_SYST_WIDE);
+ PFM_CPUINFO_CLEAR(PFM_CPUINFO_EXCL_IDLE);
- ia64_srlz_i();
+ /*
+ * save PMDs in context
+ * release ownership
+ */
+ pfm_flush_pmds(current, ctx);
- } else {
- if ((task->thread.flags & IA64_THREAD_PM_VALID) == 0) {
- preempt_enable();
- printk(KERN_DEBUG "perfmon: pfm_start task flag not set for [%d]\n",
- task->pid);
- return -EINVAL;
- }
- /* set user level psr.up */
- ia64_psr(regs)->up = 1;
+ /*
+ * at this point we are done with the PMU
+ * so we can unreserve the resource.
+ */
+ pfm_unreserve_session(ctx, 1 , ctx->ctx_cpu);
- /* start monitoring at kernel level */
- pfm_set_psr_up();
+ /*
+ * disconnect context from task
+ */
+ task->thread.pfm_context = NULL;
+ /*
+ * disconnect task from context
+ */
+ ctx->ctx_task = NULL;
- ia64_srlz_i();
+ /*
+ * There is nothing more to cleanup here.
+ */
+ return 0;
}
- preempt_enable();
- return 0;
-}
+ /*
+ * per-task mode
+ */
+ tregs = task == current ? regs : ia64_task_regs(task);
-static int
-pfm_enable(struct task_struct *task, pfm_context_t *ctx, void *arg, int count,
- struct pt_regs *regs)
-{
- int me;
+ if (task == current || ctx->ctx_fl_unsecure) {
+ /*
+ * cancel user level control
+ */
+ ia64_psr(regs)->sp = 1;
+ DPRINT(("setting psr.sp for [%d]\n", task->pid));
- /* we don't quite support this right now */
- if (task != current) return -EINVAL;
+ }
+ /*
+ * save PMDs to context
+ * release ownership
+ */
+ pfm_flush_pmds(task, ctx);
- me = get_cpu(); /* make sure we're not migrated or preempted */
+ /*
+ * at this point we are done with the PMU
+ * so we can unreserve the resource.
+ */
+ pfm_unreserve_session(ctx, 0 , ctx->ctx_cpu);
- if (ctx->ctx_fl_system == 0 && PMU_OWNER() && PMU_OWNER() != current)
- pfm_lazy_save_regs(PMU_OWNER());
+ /*
+ * reset activation counter and psr
+ */
+ ctx->ctx_last_activation = PFM_INVALID_ACTIVATION;
+ SET_LAST_CPU(ctx, -1);
- /* reset all registers to stable quiet state */
- pfm_reset_pmu(task);
+ /*
+ * PMU state will not be restored
+ */
+ task->thread.flags &= ~IA64_THREAD_PM_VALID;
- /* make sure nothing starts */
- if (ctx->ctx_fl_system) {
- ia64_psr(regs)->pp = 0;
- ia64_psr(regs)->up = 0; /* just to make sure! */
+ /*
+ * break links between context and task
+ */
+ task->thread.pfm_context = NULL;
+ ctx->ctx_task = NULL;
- /* make sure monitoring is stopped */
- pfm_clear_psr_pp();
- ia64_srlz_i();
+ PFM_SET_WORK_PENDING(task, 0);
+ ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_NONE;
- PFM_CPUINFO_CLEAR(PFM_CPUINFO_DCR_PP);
- PFM_CPUINFO_SET(PFM_CPUINFO_SYST_WIDE);
- if (ctx->ctx_fl_excl_idle) PFM_CPUINFO_SET(PFM_CPUINFO_EXCL_IDLE);
- } else {
- /*
- * needed in case the task was a passive task during
- * a system wide session and now wants to have its own
- * session
- */
- ia64_psr(regs)->pp = 0; /* just to make sure! */
- ia64_psr(regs)->up = 0;
+ DPRINT(("disconnected [%d] from context\n", task->pid));
- /* make sure monitoring is stopped */
- pfm_clear_psr_up();
- ia64_srlz_i();
+ return 0;
+}
- DBprintk(("clearing psr.sp for [%d]\n", current->pid));
+static void
+pfm_force_cleanup(pfm_context_t *ctx, struct pt_regs *regs)
+{
+ struct task_struct *task = ctx->ctx_task;
- /* allow user level control */
- ia64_psr(regs)->sp = 0;
+ ia64_psr(regs)->up = 0;
+ ia64_psr(regs)->sp = 1;
- /* PMU state will be saved/restored on ctxsw */
- task->thread.flags |= IA64_THREAD_PM_VALID;
+ if (GET_PMU_OWNER() == task) {
+ DPRINT(("cleared ownership for [%d]\n", ctx->ctx_task->pid));
+ SET_PMU_OWNER(NULL, NULL);
}
- SET_PMU_OWNER(task);
-
- ctx->ctx_flags.state = PFM_CTX_ENABLED;
- atomic_set(&ctx->ctx_last_cpu, me);
-
- /* simply unfreeze */
- pfm_unfreeze_pmu();
+ /*
+ * disconnect the task from the context and vice-versa
+ */
+ PFM_SET_WORK_PENDING(task, 0);
- put_cpu();
+ task->thread.pfm_context = NULL;
+ task->thread.flags &= ~IA64_THREAD_PM_VALID;
- return 0;
+ DPRINT(("context <%d> force cleanup for [%d] by [%d]\n", ctx->ctx_fd, task->pid, current->pid));
}
-static int
-pfm_get_pmc_reset(struct task_struct *task, pfm_context_t *ctx, void *arg, int count,
- struct pt_regs *regs)
+
+/*
+ * called only from exit_thread(): task == current
+ */
+void
+pfm_exit_thread(struct task_struct *task)
{
- pfarg_reg_t tmp, *req = (pfarg_reg_t *)arg;
- unsigned int cnum;
- int i, ret = -EINVAL;
+ pfm_context_t *ctx;
+ unsigned long flags;
+ struct pt_regs *regs = ia64_task_regs(task);
+ int ret;
+ int free_ok = 0;
- for (i = 0; i < count; i++, req++) {
+ ctx = PFM_GET_CTX(task);
- if (__copy_from_user(&tmp, req, sizeof(tmp))) return -EFAULT;
+ PROTECT_CTX(ctx, flags);
- cnum = tmp.reg_num;
+ DPRINT(("state=%d task [%d]\n", ctx->ctx_state, task->pid));
- if (!PMC_IS_IMPL(cnum)) goto abort_mission;
+ /*
+ * come here only if attached
+ */
+ if (unlikely(CTX_IS_UNLOADED(ctx))) {
+ printk(KERN_ERR "perfmon: pfm_exit_thread [%d] ctx unloaded\n", task->pid);
+ goto skip_all;
+ }
+
+ if (CTX_IS_LOADED(ctx) || CTX_IS_MASKED(ctx)) {
+
+ ret = pfm_context_unload(ctx, NULL, 0, regs);
+ if (ret) {
+ printk(KERN_ERR "perfmon: pfm_exit_thread [%d] state=%d unload failed %d\n", task->pid, ctx->ctx_state, ret);
+ }
+ CTX_TERMINATED(ctx);
+ DPRINT(("ctx terminated by [%d]\n", task->pid));
- tmp.reg_value = PMC_DFL_VAL(cnum);
+ pfm_end_notify_user(ctx);
- PFM_REG_RETFLAG_SET(tmp.reg_flags, 0);
+ } else if (CTX_IS_ZOMBIE(ctx)) {
+ pfm_clear_psr_up();
+
+ BUG_ON(ctx->ctx_smpl_hdr);
- DBprintk(("pmc_reset_val pmc[%u]=0x%lx\n", cnum, tmp.reg_value));
+ pfm_force_cleanup(ctx, regs);
- if (__copy_to_user(req, &tmp, sizeof(tmp))) return -EFAULT;
+ free_ok = 1;
}
- return 0;
-abort_mission:
- PFM_REG_RETFLAG_SET(tmp.reg_flags, PFM_REG_RETFL_EINVAL);
- if (__copy_to_user(req, &tmp, sizeof(tmp))) ret = -EFAULT;
+ { u64 psr = pfm_get_psr();
+ BUG_ON(psr & (IA64_PSR_UP|IA64_PSR_PP));
+ }
+skip_all:
+ UNPROTECT_CTX(ctx, flags);
- return ret;
+ /*
+ * All memory free operations (especially for vmalloc'ed memory)
+ * MUST be done with interrupts ENABLED.
+ */
+ if (free_ok) pfm_context_free(ctx);
}
/*
* functions MUST be listed in the increasing order of their index (see permfon.h)
*/
+#define PFM_CMD(name, flags, arg_count, arg_type, getsz) { name, #name, flags, arg_count, sizeof(arg_type), getsz }
+#define PFM_CMD_S(name, flags) { name, #name, flags, 0, 0, NULL }
+#define PFM_CMD_PCLRWS (PFM_CMD_FD|PFM_CMD_ARG_RW|PFM_CMD_STOP)
+#define PFM_CMD_PCLRW (PFM_CMD_FD|PFM_CMD_ARG_RW)
+#define PFM_CMD_NONE { NULL, "no-cmd", 0, 0, 0, NULL}
+
static pfm_cmd_desc_t pfm_cmd_tab[]={
-/* 0 */{ NULL, 0, 0, 0}, /* not used */
-/* 1 */{ pfm_write_pmcs, PFM_CMD_PID|PFM_CMD_CTX|PFM_CMD_ARG_RW, PFM_CMD_ARG_MANY, sizeof(pfarg_reg_t)},
-/* 2 */{ pfm_write_pmds, PFM_CMD_PID|PFM_CMD_CTX|PFM_CMD_ARG_RW, PFM_CMD_ARG_MANY, sizeof(pfarg_reg_t)},
-/* 3 */{ pfm_read_pmds,PFM_CMD_PID|PFM_CMD_CTX|PFM_CMD_ARG_RW, PFM_CMD_ARG_MANY, sizeof(pfarg_reg_t)},
-/* 4 */{ pfm_stop, PFM_CMD_PID|PFM_CMD_CTX, 0, 0},
-/* 5 */{ pfm_start, PFM_CMD_PID|PFM_CMD_CTX, 0, 0},
-/* 6 */{ pfm_enable, PFM_CMD_PID|PFM_CMD_CTX, 0, 0},
-/* 7 */{ pfm_disable, PFM_CMD_PID|PFM_CMD_CTX, 0, 0},
-/* 8 */{ pfm_context_create, PFM_CMD_PID|PFM_CMD_ARG_RW, 1, sizeof(pfarg_context_t)},
-/* 9 */{ pfm_context_destroy, PFM_CMD_PID|PFM_CMD_CTX, 0, 0},
-/* 10 */{ pfm_restart, PFM_CMD_PID|PFM_CMD_CTX|PFM_CMD_NOCHK, 0, 0},
-/* 11 */{ pfm_protect_context, PFM_CMD_PID|PFM_CMD_CTX, 0, 0},
-/* 12 */{ pfm_get_features, PFM_CMD_ARG_RW, 0, 0},
-/* 13 */{ pfm_debug, 0, 1, sizeof(unsigned int)},
-/* 14 */{ pfm_context_unprotect, PFM_CMD_PID|PFM_CMD_CTX, 0, 0},
-/* 15 */{ pfm_get_pmc_reset, PFM_CMD_ARG_RW, PFM_CMD_ARG_MANY, sizeof(pfarg_reg_t)},
-/* 16 */{ NULL, 0, 0, 0}, /* not used */
-/* 17 */{ NULL, 0, 0, 0}, /* not used */
-/* 18 */{ NULL, 0, 0, 0}, /* not used */
-/* 19 */{ NULL, 0, 0, 0}, /* not used */
-/* 20 */{ NULL, 0, 0, 0}, /* not used */
-/* 21 */{ NULL, 0, 0, 0}, /* not used */
-/* 22 */{ NULL, 0, 0, 0}, /* not used */
-/* 23 */{ NULL, 0, 0, 0}, /* not used */
-/* 24 */{ NULL, 0, 0, 0}, /* not used */
-/* 25 */{ NULL, 0, 0, 0}, /* not used */
-/* 26 */{ NULL, 0, 0, 0}, /* not used */
-/* 27 */{ NULL, 0, 0, 0}, /* not used */
-/* 28 */{ NULL, 0, 0, 0}, /* not used */
-/* 29 */{ NULL, 0, 0, 0}, /* not used */
-/* 30 */{ NULL, 0, 0, 0}, /* not used */
-/* 31 */{ NULL, 0, 0, 0}, /* not used */
-#ifdef PFM_PMU_USES_DBR
-/* 32 */{ pfm_write_ibrs, PFM_CMD_PID|PFM_CMD_CTX|PFM_CMD_ARG_RW, PFM_CMD_ARG_MANY, sizeof(pfarg_dbreg_t)},
-/* 33 */{ pfm_write_dbrs, PFM_CMD_PID|PFM_CMD_CTX|PFM_CMD_ARG_RW, PFM_CMD_ARG_MANY, sizeof(pfarg_dbreg_t)}
-#endif
+/* 0 */PFM_CMD_NONE,
+/* 1 */PFM_CMD(pfm_write_pmcs, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL),
+/* 2 */PFM_CMD(pfm_write_pmds, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL),
+/* 3 */PFM_CMD(pfm_read_pmds, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL),
+/* 4 */PFM_CMD_S(pfm_stop, PFM_CMD_PCLRWS),
+/* 5 */PFM_CMD_S(pfm_start, PFM_CMD_PCLRWS),
+/* 6 */PFM_CMD_NONE,
+/* 7 */PFM_CMD_NONE,
+/* 8 */PFM_CMD(pfm_context_create, PFM_CMD_ARG_RW, 1, pfarg_context_t, pfm_ctx_getsize),
+/* 9 */PFM_CMD_NONE,
+/* 10 */PFM_CMD_S(pfm_restart, PFM_CMD_PCLRW),
+/* 11 */PFM_CMD_NONE,
+/* 12 */PFM_CMD(pfm_get_features, PFM_CMD_ARG_RW, 1, pfarg_features_t, NULL),
+/* 13 */PFM_CMD(pfm_debug, 0, 1, unsigned int, NULL),
+/* 14 */PFM_CMD_NONE,
+/* 15 */PFM_CMD(pfm_get_pmc_reset, PFM_CMD_ARG_RW, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL),
+/* 16 */PFM_CMD(pfm_context_load, PFM_CMD_PCLRWS, 1, pfarg_load_t, NULL),
+/* 17 */PFM_CMD_S(pfm_context_unload, PFM_CMD_PCLRWS),
+/* 18 */PFM_CMD_NONE,
+/* 19 */PFM_CMD_NONE,
+/* 20 */PFM_CMD_NONE,
+/* 21 */PFM_CMD_NONE,
+/* 22 */PFM_CMD_NONE,
+/* 23 */PFM_CMD_NONE,
+/* 24 */PFM_CMD_NONE,
+/* 25 */PFM_CMD_NONE,
+/* 26 */PFM_CMD_NONE,
+/* 27 */PFM_CMD_NONE,
+/* 28 */PFM_CMD_NONE,
+/* 29 */PFM_CMD_NONE,
+/* 30 */PFM_CMD_NONE,
+/* 31 */PFM_CMD_NONE,
+/* 32 */PFM_CMD(pfm_write_ibrs, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_dbreg_t, NULL),
+/* 33 */PFM_CMD(pfm_write_dbrs, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_dbreg_t, NULL)
};
-#define PFM_CMD_COUNT ARRAY_SIZE(pfm_cmd_tab)
+#define PFM_CMD_COUNT (sizeof(pfm_cmd_tab)/sizeof(pfm_cmd_desc_t))
static int
-check_task_state(struct task_struct *task)
+pfm_check_task_state(pfm_context_t *ctx, int cmd, unsigned long flags)
{
- int ret = 0;
-#ifdef CONFIG_SMP
- /* We must wait until the state has been completely
- * saved. There can be situations where the reader arrives before
- * after the task is marked as STOPPED but before pfm_save_regs()
- * is completed.
- */
- if (task->state != TASK_ZOMBIE && task->state != TASK_STOPPED) return -EBUSY;
- DBprintk(("before wait_task_inactive [%d] state %ld\n", task->pid, task->state));
- wait_task_inactive(task);
- DBprintk(("after wait_task_inactive [%d] state %ld\n", task->pid, task->state));
-#else
- if (task->state != TASK_ZOMBIE && task->state != TASK_STOPPED) {
- DBprintk(("warning [%d] not in stable state %ld\n", task->pid, task->state));
- ret = -EBUSY;
+ struct task_struct *task;
+
+ task = PFM_CTX_TASK(ctx);
+ if (task == NULL) {
+ DPRINT(("context %d no task, state=%d\n", ctx->ctx_fd, ctx->ctx_state));
+ return 0;
}
-#endif
- return ret;
+
+ DPRINT(("context %d state=%d [%d] task_state=%ld must_stop=%d\n",
+ ctx->ctx_fd,
+ ctx->ctx_state,
+ task->pid,
+ task->state, PFM_CMD_STOPPED(cmd)));
+
+ /*
+ * self-monitoring always ok.
+ *
+ * for system-wide the caller can either be the creator of the
+ * context (to one to which the context is attached to) OR
+ * a task running on the same CPU as the session.
+ */
+ if (task == current || ctx->ctx_fl_system) return 0;
+
+ /*
+ * context is UNLOADED, MASKED, TERMINATED we are safe to go
+ */
+ if (CTX_IS_LOADED(ctx) == 0) return 0;
+
+ if (CTX_IS_ZOMBIE(ctx)) return -EINVAL;
+
+ /*
+ * context is loaded, we must make sure the task is stopped
+ * We could lift this restriction for UP but it would mean that
+ * the user has no guarantee the task would not run between
+ * two successive calls to perfmonctl(). That's probably OK.
+ * If this user wants to ensure the task does not run, then
+ * the task must be stopped.
+ */
+ if (PFM_CMD_STOPPED(cmd) && task->state != TASK_STOPPED) {
+ DPRINT(("[%d] task not in stopped state\n", task->pid));
+ return -EBUSY;
+ }
+
+ UNPROTECT_CTX(ctx, flags);
+
+ pfm_wait_task_inactive(task);
+
+ PROTECT_CTX(ctx, flags);
+ return 0;
}
+/*
+ * system-call entry point (must return long)
+ */
asmlinkage long
-sys_perfmonctl (pid_t pid, int cmd, void *arg, int count, long arg5, long arg6, long arg7,
+sys_perfmonctl (int fd, int cmd, void *arg, int count, long arg5, long arg6, long arg7,
long arg8, long stack)
{
struct pt_regs *regs = (struct pt_regs *)&stack;
- struct task_struct *task = current;
- pfm_context_t *ctx;
- size_t sz;
- int ret, narg;
+ struct file *file = NULL;
+ pfm_context_t *ctx = NULL;
+ unsigned long flags = 0UL;
+ void *args_k = NULL;
+ long ret; /* will expand int return types */
+ size_t base_sz, sz, xtra_sz = 0;
+ int narg, completed_args = 0, call_made = 0;
+#define PFM_MAX_ARGSIZE 4096
- /*
+ /*
* reject any call if perfmon was disabled at initialization time
*/
if (PFM_IS_DISABLED()) return -ENOSYS;
- DBprintk(("cmd=%d idx=%d valid=%d narg=0x%x\n", cmd, PFM_CMD_IDX(cmd),
- PFM_CMD_IS_VALID(cmd), PFM_CMD_NARG(cmd)));
+ if (unlikely(PFM_CMD_IS_VALID(cmd) == 0)) {
+ DPRINT(("[%d] invalid cmd=%d\n", current->pid, cmd));
+ return -EINVAL;
+ }
- if (PFM_CMD_IS_VALID(cmd) == 0) return -EINVAL;
+ DPRINT(("cmd=%s idx=%d valid=%d narg=0x%x argsz=%lu count=%d\n",
+ PFM_CMD_NAME(cmd),
+ PFM_CMD_IDX(cmd),
+ PFM_CMD_IS_VALID(cmd),
+ PFM_CMD_NARG(cmd),
+ PFM_CMD_ARG_SIZE(cmd), count));
- /* ingore arguments when command has none */
+ /*
+ * check if number of arguments matches what the command expects
+ */
narg = PFM_CMD_NARG(cmd);
- if ((narg == PFM_CMD_ARG_MANY && count == 0) || (narg > 0 && narg != count)) return -EINVAL;
+ if ((narg == PFM_CMD_ARG_MANY && count <= 0) || (narg > 0 && narg != count))
+ return -EINVAL;
- sz = PFM_CMD_ARG_SIZE(cmd);
+ /* get single argument size */
+ base_sz = PFM_CMD_ARG_SIZE(cmd);
- if (PFM_CMD_READ_ARG(cmd) && !access_ok(VERIFY_READ, arg, sz*count)) return -EFAULT;
+restart_args:
+ sz = xtra_sz + base_sz*count;
+ /*
+ * limit abuse to min page size
+ */
+ if (unlikely(sz > PFM_MAX_ARGSIZE)) {
+ printk(KERN_ERR "perfmon: [%d] argument too big %lu\n", current->pid, sz);
+ return -E2BIG;
+ }
- if (PFM_CMD_RW_ARG(cmd) && !access_ok(VERIFY_WRITE, arg, sz*count)) return -EFAULT;
+ /*
+ * allocate default-sized argument buffer
+ */
+ if (count && args_k == NULL) {
+ args_k = kmalloc(PFM_MAX_ARGSIZE, GFP_KERNEL);
+ if (args_k == NULL) return -ENOMEM;
+ }
- if (PFM_CMD_USE_PID(cmd)) {
- /*
- * XXX: may need to fine tune this one
- */
- if (pid < 2) return -EPERM;
+ ret = -EFAULT;
- if (pid != current->pid) {
+ /*
+ * copy arguments
+ *
+ * assume sz = 0 for command without parameters
+ */
+ if (sz && copy_from_user(args_k, arg, sz)) {
+ DPRINT(("[%d] cannot copy_from_user %lu bytes @%p\n", current->pid, sz, arg));
+ goto error_args;
+ }
- ret = -ESRCH;
+ /*
+ * check if command supports extra parameters
+ */
+ if (completed_args == 0 && PFM_CMD_GETSIZE(cmd)) {
+ /*
+ * get extra parameters size (based on main argument)
+ */
+ ret = PFM_CMD_GETSIZE(cmd)(args_k, &xtra_sz);
+ if (ret) goto error_args;
- read_lock(&tasklist_lock);
+ completed_args = 1;
- task = find_task_by_pid(pid);
+ DPRINT(("[%d] restart_args sz=%lu xtra_sz=%lu\n", current->pid, sz, xtra_sz));
- if (task) get_task_struct(task);
+ /* retry if necessary */
+ if (xtra_sz) goto restart_args;
+ }
- read_unlock(&tasklist_lock);
+ if (PFM_CMD_USE_FD(cmd)) {
- if (!task) goto abort_call;
+ ret = -EBADF;
- ret = -EPERM;
+ file = fget(fd);
+ if (file == NULL) {
+ DPRINT(("[%d] invalid fd %d\n", current->pid, fd));
+ goto error_args;
+ }
+ if (PFM_IS_FILE(file) == 0) {
+ DPRINT(("[%d] fd %d not related to perfmon\n", current->pid, fd));
+ goto error_args;
+ }
- if (pfm_bad_permissions(task)) goto abort_call;
- if (PFM_CMD_CHK(cmd)) {
- ret = check_task_state(task);
- if (ret != 0) goto abort_call;
- }
+ ctx = (pfm_context_t *)file->private_data;
+ if (ctx == NULL) {
+ DPRINT(("[%d] no context for fd %d\n", current->pid, fd));
+ goto error_args;
}
- }
- ctx = task->thread.pfm_context;
+ PROTECT_CTX(ctx, flags);
- if (PFM_CMD_USE_CTX(cmd)) {
- ret = -EINVAL;
- if (ctx == NULL) {
- DBprintk(("no context for task %d\n", task->pid));
- goto abort_call;
- }
- ret = -EPERM;
- /*
- * we only grant access to the context if:
- * - the caller is the creator of the context (ctx_owner)
- * OR - the context is attached to the caller AND The context IS NOT
- * in protected mode
- */
- if (ctx->ctx_owner != current && (ctx->ctx_fl_protected || task != current)) {
- DBprintk(("context protected, no access for [%d]\n", task->pid));
- goto abort_call;
- }
- }
-
- ret = (*pfm_cmd_tab[PFM_CMD_IDX(cmd)].cmd_func)(task, ctx, arg, count, regs);
-
-abort_call:
- if (task && task != current) put_task_struct(task);
+ /*
+ * check task is stopped
+ */
+ ret = pfm_check_task_state(ctx, cmd, flags);
+ if (ret) goto abort_locked;
+ }
- return ret;
-}
+ ret = (*pfm_cmd_tab[PFM_CMD_IDX(cmd)].cmd_func)(ctx, args_k, count, regs);
-/*
- * send SIGPROF to register task, must be invoked when it
- * is safe to send a signal, e.g., not holding any runqueue
- * related locks.
- */
-static int
-pfm_notify_user(pfm_context_t *ctx)
-{
- struct siginfo si;
- int ret;
+ call_made = 1;
- if (ctx->ctx_notify_task == NULL) {
- DBprintk(("[%d] no notifier\n", current->pid));
- return -EINVAL;
+abort_locked:
+ if (ctx) {
+ DPRINT(("[%d] context unlocked\n", current->pid));
+ UNPROTECT_CTX(ctx, flags);
+ fput(file);
}
- si.si_errno = 0;
- si.si_addr = NULL;
- si.si_pid = current->pid; /* who is sending */
- si.si_signo = SIGPROF;
- si.si_code = PROF_OVFL;
+ /* copy argument back to user, if needed */
+ if (call_made && PFM_CMD_RW_ARG(cmd) && copy_to_user(arg, args_k, base_sz*count)) ret = -EFAULT;
- si.si_pfm_ovfl[0] = ctx->ctx_ovfl_regs[0];
+error_args:
+ if (args_k) kfree(args_k);
- /*
- * when the target of the signal is not ourself, we have to be more
- * careful. The notify_task may being cleared by the target task itself
- * in release_thread(). We must ensure mutual exclusion here such that
- * the signal is delivered (even to a dying task) safely.
- */
+ return ret;
+}
- if (ctx->ctx_notify_task != current) {
- /*
- * grab the notification lock for this task
- * This guarantees that the sequence: test + send_signal
- * is atomic with regards to the ctx_notify_task field.
- *
- * We need a spinlock and not just an atomic variable for this.
- *
- */
- spin_lock(&ctx->ctx_lock);
+static void
+pfm_resume_after_ovfl(pfm_context_t *ctx, unsigned long ovfl_regs, struct pt_regs *regs)
+{
+ pfm_buffer_fmt_t *fmt = ctx->ctx_buf_fmt;
+ pfm_ovfl_ctrl_t rst_ctrl;
+ int ret = 0;
- /*
- * now notify_task cannot be modified until we're done
- * if NULL, they it got modified while we were in the handler
- */
- if (ctx->ctx_notify_task == NULL) {
+ /*
+ * Unlock sampling buffer and reset index atomically
+ * XXX: not really needed when blocking
+ */
+ if (CTX_HAS_SMPL(ctx)) {
- spin_unlock(&ctx->ctx_lock);
+ rst_ctrl.stop_monitoring = 1;
+ rst_ctrl.reset_pmds = PFM_PMD_NO_RESET;
- /*
- * If we've lost the notified task, then we will run
- * to completion wbut keep the PMU frozen. Results
- * will be incorrect anyway. We do not kill task
- * to leave it possible to attach perfmon context
- * to already running task.
- */
- printk("perfmon: pfm_notify_user() lost notify_task\n");
- DBprintk_ovfl(("notification task has disappeared !\n"));
+ /* XXX: check return value */
+ if (fmt->fmt_restart)
+ ret = (*fmt->fmt_restart)(current, &rst_ctrl, ctx->ctx_smpl_hdr, regs);
+ } else {
+ rst_ctrl.stop_monitoring = 0;
+ rst_ctrl.reset_pmds = PFM_PMD_LONG_RESET;
+ }
- /* we cannot afford to block now */
- ctx->ctx_fl_block = 0;
+ if (ret == 0) {
+ if (rst_ctrl.reset_pmds != PFM_PMD_NO_RESET)
+ pfm_reset_regs(ctx, &ovfl_regs, rst_ctrl.reset_pmds);
- return -EINVAL;
+ if (rst_ctrl.stop_monitoring == 0) {
+ DPRINT(("resuming monitoring\n"));
+ if (CTX_IS_MASKED(ctx)) pfm_restore_monitoring(current);
+ } else {
+ DPRINT(("stopping monitoring\n"));
+ //pfm_stop_monitoring(current, regs);
}
+ CTX_LOADED(ctx);
+ }
+}
- /*
- * required by send_sig_info() to make sure the target
- * task does not disappear on us.
- */
- read_lock(&tasklist_lock);
+
+/*
+ * context MUST BE LOCKED when calling
+ * can only be called for current
+ */
+static void
+pfm_context_force_terminate(pfm_context_t *ctx, struct pt_regs *regs)
+{
+ if (ctx->ctx_fl_system) {
+ printk(KERN_ERR "perfmon: pfm_context_force_terminate [%d] is system-wide\n", current->pid);
+ return;
}
/*
- * in this case, we don't stop the task, we let it go on. It will
- * necessarily go to the signal handler (if any) when it goes back to
- * user mode.
- */
- DBprintk_ovfl(("[%d] sending notification to [%d]\n",
- current->pid, ctx->ctx_notify_task->pid));
+ * we stop the whole thing, we do no need to flush
+ * we know we WERE masked
+ */
+ pfm_clear_psr_up();
+ ia64_psr(regs)->up = 0;
+ ia64_psr(regs)->sp = 1;
- /*
- * this call is safe in an interrupt handler, so does read_lock() on tasklist_lock
+ /*
+ * disconnect the task from the context and vice-versa
*/
- ret = send_sig_info(SIGPROF, &si, ctx->ctx_notify_task);
- if (ret) {
- printk("perfmon: send_sig_info(process %d, SIGPROF)=%d\n",
- ctx->ctx_notify_task->pid, ret);
- }
+ current->thread.pfm_context = NULL;
+ current->thread.flags &= ~IA64_THREAD_PM_VALID;
+ ctx->ctx_task = NULL;
+
+ /*
+ * switch to terminated state
+ */
+ CTX_TERMINATED(ctx);
+
+ DPRINT(("context <%d> terminated for [%d]\n", ctx->ctx_fd, current->pid));
+
+ /*
+ * and wakeup controlling task, indicating we are now disconnected
+ */
+ wake_up_interruptible(&ctx->ctx_zombieq);
/*
- * now undo the protections in order
+ * given that context is still locked, the controlling
+ * task will only get access when we return from
+ * pfm_handle_work().
*/
- if (ctx->ctx_notify_task != current) {
- read_unlock(&tasklist_lock);
- spin_unlock(&ctx->ctx_lock);
- }
- return ret;
}
+static int pfm_ovfl_notify_user(pfm_context_t *ctx, unsigned long ovfl_pmds);
+
void
-pfm_ovfl_block_reset(void)
+pfm_handle_work(void)
{
- struct thread_struct *th = ¤t->thread;
- pfm_context_t *ctx = current->thread.pfm_context;
+ pfm_context_t *ctx;
+ struct pt_regs *regs;
+ unsigned long flags;
+ unsigned long ovfl_regs;
unsigned int reason;
int ret;
- /*
- * clear the flag, to make sure we won't get here
- * again
- */
- th->pfm_ovfl_block_reset = 0;
- clear_thread_flag(TIF_NOTIFY_RESUME);
-
- /*
- * do some sanity checks first
- */
- if (!ctx) {
+ ctx = PFM_GET_CTX(current);
+ if (ctx == NULL) {
printk(KERN_ERR "perfmon: [%d] has no PFM context\n", current->pid);
return;
}
+
+ PROTECT_CTX(ctx, flags);
+
+ PFM_SET_WORK_PENDING(current, 0);
+
+ pfm_clear_task_notify();
+
+ regs = ia64_task_regs(current);
+
/*
* extract reason for being here and clear
*/
reason = ctx->ctx_fl_trap_reason;
ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_NONE;
- DBprintk(("[%d] reason=%d\n", current->pid, reason));
+ DPRINT(("[%d] reason=%d\n", current->pid, reason));
/*
- * just here for a reset (non-blocking context only)
+ * must be done before we check non-blocking mode
*/
- if (reason == PFM_TRAP_REASON_RESET) goto non_blocking;
+ if (ctx->ctx_fl_going_zombie || CTX_IS_ZOMBIE(ctx)) goto do_zombie;
- /*
- * first notify user. This can fail if notify_task has disappeared.
- */
- if (reason == PFM_TRAP_REASON_SIG || reason == PFM_TRAP_REASON_BLOCKSIG) {
- ret = pfm_notify_user(ctx);
- if (ret) return;
- }
+ ovfl_regs = ctx->ctx_ovfl_regs[0];
- /*
- * came here just to signal (non-blocking)
- */
- if (reason == PFM_TRAP_REASON_SIG) return;
+ //if (CTX_OVFL_NOBLOCK(ctx)) goto skip_blocking;
+ if (reason == PFM_TRAP_REASON_RESET) goto skip_blocking;
+
+ UNPROTECT_CTX(ctx, flags);
- DBprintk(("[%d] before sleeping\n", current->pid));
+ DPRINT(("before block sleeping\n"));
/*
* may go through without blocking on SMP systems
*/
ret = down_interruptible(&ctx->ctx_restart_sem);
- DBprintk(("[%d] after sleeping ret=%d\n", current->pid, ret));
+ DPRINT(("after block sleeping ret=%d\n", ret));
+ PROTECT_CTX(ctx, flags);
+
+ if (ctx->ctx_fl_going_zombie) {
+do_zombie:
+ DPRINT(("context is zombie, bailing out\n"));
+ pfm_context_force_terminate(ctx, regs);
+ goto nothing_to_do;
+ }
/*
* in case of interruption of down() we don't restart anything
*/
- if (ret >= 0) {
-
-non_blocking:
- /* we reactivate on context switch */
- ctx->ctx_fl_frozen = 0;
- /*
- * the ovfl_sem is cleared by the restart task and this is safe because we always
- * use the local reference
- */
-
- pfm_reset_regs(ctx, ctx->ctx_ovfl_regs, PFM_PMD_LONG_RESET);
-
- ctx->ctx_ovfl_regs[0] = 0UL;
+ if (ret < 0) goto nothing_to_do;
- /*
- * Unlock sampling buffer and reset index atomically
- * XXX: not really needed when blocking
- */
- if (CTX_HAS_SMPL(ctx)) {
- ctx->ctx_psb->psb_hdr->hdr_count = 0;
- ctx->ctx_psb->psb_index = 0;
- }
+skip_blocking:
+ pfm_resume_after_ovfl(ctx, ovfl_regs, regs);
+ ctx->ctx_ovfl_regs[0] = 0UL;
- pfm_unfreeze_pmu();
+nothing_to_do:
- /* state restored, can go back to work (user mode) */
- }
+ UNPROTECT_CTX(ctx, flags);
}
-/*
- * This function will record an entry in the sampling if it is not full already.
- * Return:
- * 0 : buffer is not full (did not BECOME full: still space or was already full)
- * 1 : buffer is full (recorded the last entry)
- */
static int
-pfm_record_sample(struct task_struct *task, pfm_context_t *ctx, unsigned long ovfl_mask, struct pt_regs *regs)
+pfm_notify_user(pfm_context_t *ctx, pfm_msg_t *msg)
{
- pfm_smpl_buffer_desc_t *psb = ctx->ctx_psb;
- unsigned long *e, m, idx;
- perfmon_smpl_entry_t *h;
- int j;
+ if (CTX_IS_ZOMBIE(ctx)) {
+ DPRINT(("ignoring overflow notification, owner is zombie\n"));
+ return 0;
+ }
+ DPRINT(("[%d] waking up somebody\n", current->pid));
- idx = ia64_fetch_and_add(1, &psb->psb_index);
- DBprintk_ovfl(("recording index=%ld entries=%ld\n", idx-1, psb->psb_entries));
+ if (msg) wake_up_interruptible(&ctx->ctx_msgq_wait);
/*
- * XXX: there is a small chance that we could run out on index before resetting
- * but index is unsigned long, so it will take some time.....
- * We use > instead of == because fetch_and_add() is off by one (see below)
- *
- * This case can happen in non-blocking mode or with multiple processes.
- * For non-blocking, we need to reload and continue.
- */
- if (idx > psb->psb_entries) return 0;
+ * safe, we are not in intr handler, nor in ctxsw when
+ * we come here
+ */
+ kill_fasync (&ctx->ctx_async_queue, SIGIO, POLL_IN);
+
+ return 0;
+}
- /* first entry is really entry 0, not 1 caused by fetch_and_add */
- idx--;
+static int
+pfm_ovfl_notify_user(pfm_context_t *ctx, unsigned long ovfl_pmds)
+{
+ pfm_msg_t *msg = NULL;
- h = (perfmon_smpl_entry_t *)(((char *)psb->psb_addr) + idx*(psb->psb_entry_size));
+ if (ctx->ctx_fl_no_msg == 0) {
+ msg = pfm_get_new_msg(ctx);
+ if (msg == NULL) {
+ printk(KERN_ERR "perfmon: pfm_ovfl_notify_user no more notification msgs\n");
+ return -1;
+ }
- /*
- * initialize entry header
- */
- h->pid = current->pid;
- h->cpu = get_cpu();
- h->last_reset_value = ovfl_mask ? ctx->ctx_soft_pmds[ffz(~ovfl_mask)].lval : 0UL;
- h->ip = regs ? regs->cr_iip | ((regs->cr_ipsr >> 41) & 0x3): 0x0UL;
- h->regs = ovfl_mask; /* which registers overflowed */
+ msg->pfm_ovfl_msg.msg_type = PFM_MSG_OVFL;
+ msg->pfm_ovfl_msg.msg_ctx_fd = ctx->ctx_fd;
+ msg->pfm_ovfl_msg.msg_tstamp = ia64_get_itc(); /* relevant on UP only */
+ msg->pfm_ovfl_msg.msg_active_set = 0;
+ msg->pfm_ovfl_msg.msg_ovfl_pmds[0] = ovfl_pmds;
+ msg->pfm_ovfl_msg.msg_ovfl_pmds[1] = msg->pfm_ovfl_msg.msg_ovfl_pmds[2] = msg->pfm_ovfl_msg.msg_ovfl_pmds[3] = 0UL;
- /* guaranteed to monotonically increase on each cpu */
- h->stamp = pfm_get_stamp();
+ }
- /* position for first pmd */
- e = (unsigned long *)(h+1);
+ DPRINT(("ovfl msg: msg=%p no_msg=%d fd=%d pid=%d ovfl_pmds=0x%lx\n",
+ msg,
+ ctx->ctx_fl_no_msg,
+ ctx->ctx_fd,
+ current->pid,
+ ovfl_pmds));
- /*
- * selectively store PMDs in increasing index number
- */
- m = ctx->ctx_smpl_regs[0];
- for (j=0; m; m >>=1, j++) {
+ return pfm_notify_user(ctx, msg);
+}
- if ((m & 0x1) == 0) continue;
+static int
+pfm_end_notify_user(pfm_context_t *ctx)
+{
+ pfm_msg_t *msg;
- if (PMD_IS_COUNTING(j)) {
- *e = pfm_read_soft_counter(ctx, j);
- } else {
- *e = ia64_get_pmd(j); /* slow */
- }
- DBprintk_ovfl(("e=%p pmd%d =0x%lx\n", (void *)e, j, *e));
- e++;
+ msg = pfm_get_new_msg(ctx);
+ if (msg == NULL) {
+ printk(KERN_ERR "perfmon: pfm_end_notify_user no more notification msgs\n");
+ return -1;
}
- pfm_stats[h->cpu].pfm_recorded_samples_count++;
- /*
- * make the new entry visible to user, needs to be atomic
- */
- ia64_fetch_and_add(1, &psb->psb_hdr->hdr_count);
+ msg->pfm_end_msg.msg_type = PFM_MSG_END;
+ msg->pfm_end_msg.msg_ctx_fd = ctx->ctx_fd;
+ msg->pfm_ovfl_msg.msg_tstamp = ia64_get_itc(); /* relevant on UP only */
- DBprintk_ovfl(("index=%ld entries=%ld hdr_count=%ld\n",
- idx, psb->psb_entries, psb->psb_hdr->hdr_count));
- /*
- * sampling buffer full ?
- */
- if (idx == (psb->psb_entries-1)) {
- DBprintk_ovfl(("sampling buffer full\n"));
- /*
- * XXX: must reset buffer in blocking mode and lost notified
- */
- pfm_stats[h->cpu].pfm_full_smpl_buffer_count++;
- put_cpu();
- return 1;
- }
- put_cpu();
- return 0;
+ DPRINT(("end msg: msg=%p no_msg=%d ctx_fd=%d pid=%d\n",
+ msg,
+ ctx->ctx_fl_no_msg,
+ ctx->ctx_fd, current->pid));
+
+ return pfm_notify_user(ctx, msg);
}
/*
* main overflow processing routine.
- * it can be called from the interrupt path or explicitly during the context switch code
- * Arguments:
- * mode: 0=coming from PMU interrupt, 1=coming from ctxsw
- *
- * Return:
- * new value of pmc[0]. if 0x0 then unfreeze, else keep frozen
+ * it can be called from the interrupt path or explicitely during the context switch code
*/
-static unsigned long
-pfm_overflow_handler(int mode, struct task_struct *task, pfm_context_t *ctx, u64 pmc0, struct pt_regs *regs)
+static void
+pfm_overflow_handler(struct task_struct *task, pfm_context_t *ctx, u64 pmc0, struct pt_regs *regs)
{
- struct thread_struct *t;
+ pfm_ovfl_arg_t ovfl_arg;
unsigned long mask;
unsigned long old_val;
- unsigned long ovfl_notify = 0UL, ovfl_pmds = 0UL;
- int i;
- int ret = 1;
- /*
- * It is never safe to access the task for which the overflow interrupt is destinated
- * using the current variable as the interrupt may occur in the middle of a context switch
- * where current does not hold the task that is running yet.
- *
- * For monitoring, however, we do need to get access to the task which caused the overflow
- * to account for overflow on the counters.
- *
- * We accomplish this by maintaining a current owner of the PMU per CPU. During context
- * switch the ownership is changed in a way such that the reflected owner is always the
- * valid one, i.e. the one that caused the interrupt.
- */
+ unsigned long ovfl_notify = 0UL, ovfl_pmds = 0UL, smpl_pmds = 0UL;
+ pfm_ovfl_ctrl_t ovfl_ctrl;
+ unsigned int i, j, has_smpl, first_pmd = ~0U;
+ int must_notify = 0;
- preempt_disable();
+ if (unlikely(CTX_IS_ZOMBIE(ctx))) goto stop_monitoring;
- t = &task->thread;
-
- /*
- * XXX: debug test
- * Don't think this could happen given upfront tests
- */
- if ((t->flags & IA64_THREAD_PM_VALID) == 0 && ctx->ctx_fl_system == 0) {
- printk(KERN_DEBUG "perfmon: Spurious overflow interrupt: process %d not "
- "using perfmon\n", task->pid);
- preempt_enable_no_resched();
- return 0x1;
- }
/*
* sanity test. Should never happen
*/
- if ((pmc0 & 0x1) == 0) {
- printk(KERN_DEBUG "perfmon: pid %d pmc0=0x%lx assumption error for freeze bit\n",
- task->pid, pmc0);
- preempt_enable_no_resched();
- return 0x0;
- }
+ if (unlikely((pmc0 & 0x1) == 0)) goto sanity_check;
mask = pmc0 >> PMU_FIRST_COUNTER;
- DBprintk_ovfl(("pmc0=0x%lx pid=%d iip=0x%lx, %s"
- " mode used_pmds=0x%lx used_pmcs=0x%lx reload_pmcs=0x%lx\n",
- pmc0, task->pid, (regs ? regs->cr_iip : 0),
+ DPRINT_ovfl(("pmc0=0x%lx pid=%d iip=0x%lx, %s"
+ "used_pmds=0x%lx reload_pmcs=0x%lx\n",
+ pmc0,
+ task ? task->pid: -1,
+ (regs ? regs->cr_iip : 0),
CTX_OVFL_NOBLOCK(ctx) ? "nonblocking" : "blocking",
ctx->ctx_used_pmds[0],
- ctx->ctx_used_pmcs[0],
ctx->ctx_reload_pmcs[0]));
+ has_smpl = CTX_HAS_SMPL(ctx);
+
/*
- * First we update the virtual counters
+ * first we update the virtual counters
+ * assume there was a prior ia64_srlz_d() issued
*/
for (i = PMU_FIRST_COUNTER; mask ; i++, mask >>= 1) {
/* skip pmd which did not overflow */
if ((mask & 0x1) == 0) continue;
- DBprintk_ovfl(("pmd[%d] overflowed hw_pmd=0x%lx soft_pmd=0x%lx\n",
- i, ia64_get_pmd(i), ctx->ctx_soft_pmds[i].val));
+ DPRINT_ovfl(("pmd[%d] overflowed hw_pmd=0x%lx ctx_pmd=0x%lx\n",
+ i, ia64_get_pmd(i), ctx->ctx_pmds[i].val));
/*
* Note that the pmd is not necessarily 0 at this point as qualified events
* taken into consideration here but will be with any read of the pmd via
* pfm_read_pmds().
*/
- old_val = ctx->ctx_soft_pmds[i].val;
- ctx->ctx_soft_pmds[i].val += 1 + pmu_conf.ovfl_val;
+ old_val = ctx->ctx_pmds[i].val;
+ ctx->ctx_pmds[i].val += 1 + pmu_conf.ovfl_val;
/*
* check for overflow condition
*/
- if (old_val > ctx->ctx_soft_pmds[i].val) {
+ if (likely(old_val > ctx->ctx_pmds[i].val)) {
ovfl_pmds |= 1UL << i;
- if (PMC_OVFL_NOTIFY(ctx, i)) {
- ovfl_notify |= 1UL << i;
+ /*
+ * keep track of pmds of interest for samples
+ */
+ if (has_smpl) {
+ if (first_pmd == ~0U) first_pmd = i;
+ smpl_pmds |= ctx->ctx_pmds[i].smpl_pmds[0];
}
+
+ if (PMC_OVFL_NOTIFY(ctx, i)) ovfl_notify |= 1UL << i;
}
- DBprintk_ovfl(("soft_pmd[%d].val=0x%lx old_val=0x%lx pmd=0x%lx ovfl_pmds=0x%lx ovfl_notify=0x%lx\n",
- i, ctx->ctx_soft_pmds[i].val, old_val,
- ia64_get_pmd(i) & pmu_conf.ovfl_val, ovfl_pmds, ovfl_notify));
+
+ DPRINT_ovfl(("ctx_pmd[%d].val=0x%lx old_val=0x%lx pmd=0x%lx ovfl_pmds=0x%lx ovfl_notify=0x%lx first_pmd=%u smpl_pmds=0x%lx\n",
+ i, ctx->ctx_pmds[i].val, old_val,
+ ia64_get_pmd(i) & pmu_conf.ovfl_val, ovfl_pmds, ovfl_notify, first_pmd, smpl_pmds));
}
+ ovfl_ctrl.notify_user = ovfl_notify ? 1 : 0;
+ ovfl_ctrl.reset_pmds = ovfl_pmds && ovfl_notify == 0UL ? 1 : 0;
+ ovfl_ctrl.block = ovfl_notify ? 1 : 0;
+ ovfl_ctrl.stop_monitoring = ovfl_notify ? 1 : 0;
+
/*
- * check for sampling buffer
- *
- * if present, record sample only when a 64-bit counter has overflowed.
- * We propagate notification ONLY when buffer becomes full.
+ * when a overflow is detected, check for sampling buffer, if present, invoke
+ * record() callback.
*/
- if(CTX_HAS_SMPL(ctx) && ovfl_pmds) {
- ret = pfm_record_sample(task, ctx, ovfl_pmds, regs);
- if (ret == 1) {
- /*
- * Sampling buffer became full
- * If no notication was requested, then we reset buffer index
- * and reset registers (done below) and resume.
- * If notification requested, then defer reset until pfm_restart()
- */
- if (ovfl_notify == 0UL) {
- ctx->ctx_psb->psb_hdr->hdr_count = 0UL;
- ctx->ctx_psb->psb_index = 0UL;
+ if (ovfl_pmds && has_smpl) {
+ unsigned long start_cycles;
+ int this_cpu = smp_processor_id();
+
+ ovfl_arg.ovfl_pmds[0] = ovfl_pmds;
+ ovfl_arg.ovfl_notify[0] = ovfl_notify;
+ ovfl_arg.ovfl_ctrl = ovfl_ctrl;
+ ovfl_arg.smpl_pmds[0] = smpl_pmds;
+
+ prefetch(ctx->ctx_smpl_hdr);
+
+ ovfl_arg.pmd_value = ctx->ctx_pmds[first_pmd].val;
+ ovfl_arg.pmd_last_reset = ctx->ctx_pmds[first_pmd].lval;
+ ovfl_arg.pmd_eventid = ctx->ctx_pmds[first_pmd].eventid;
+
+ /*
+ * copy values of pmds of interest. Sampling format may copy them
+ * into sampling buffer.
+ */
+ if (smpl_pmds) {
+ for(i=0, j=0; smpl_pmds; i++, smpl_pmds >>=1) {
+ if ((smpl_pmds & 0x1) == 0) continue;
+ ovfl_arg.smpl_pmds_values[j++] = PMD_IS_COUNTING(i) ? pfm_read_soft_counter(ctx, i) : ia64_get_pmd(i);
}
- } else {
- /*
- * sample recorded in buffer, no need to notify user
- */
- ovfl_notify = 0UL;
}
- }
- /*
- * No overflow requiring a user level notification
- */
- if (ovfl_notify == 0UL) {
- if (ovfl_pmds)
- pfm_reset_regs(ctx, &ovfl_pmds, PFM_PMD_SHORT_RESET);
- preempt_enable_no_resched();
- return 0x0UL;
- }
+ pfm_stats[this_cpu].pfm_smpl_handler_calls++;
+ start_cycles = ia64_get_itc();
- /*
- * keep track of what to reset when unblocking
- */
- ctx->ctx_ovfl_regs[0] = ovfl_pmds;
+ /*
+ * call custom buffer format record (handler) routine
+ */
+ (*ctx->ctx_buf_fmt->fmt_handler)(task, ctx->ctx_smpl_hdr, &ovfl_arg, regs);
- DBprintk_ovfl(("block=%d notify [%d] current [%d]\n",
- ctx->ctx_fl_block,
- ctx->ctx_notify_task ? ctx->ctx_notify_task->pid: -1,
- current->pid ));
+ pfm_stats[this_cpu].pfm_smpl_handler_cycles += ia64_get_itc() - start_cycles;
- /*
- * ctx_notify_task could already be NULL, checked in pfm_notify_user()
- */
- if (CTX_OVFL_NOBLOCK(ctx) == 0 && ctx->ctx_notify_task != task) {
- ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_BLOCKSIG;
- } else {
- ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_SIG;
+ ovfl_pmds = ovfl_arg.ovfl_pmds[0];
+ ovfl_notify = ovfl_arg.ovfl_notify[0];
+ ovfl_ctrl = ovfl_arg.ovfl_ctrl;
+ }
+
+ if (ovfl_pmds && ovfl_ctrl.reset_pmds) {
+ pfm_reset_regs(ctx, &ovfl_pmds, ovfl_ctrl.reset_pmds);
}
- /*
- * we cannot block in system wide mode and we do not go
- * through the PMU ctxsw code. Therefore we can generate
- * the notification here. In system wide mode, the current
- * task maybe different from the task controlling the session
- * on this CPU, therefore owner can be different from current.
- *
- * In per-process mode, this function gets called from
- * the interrupt handler or pfm_load_regs(). The mode argument
- * tells where we are coming from. When coming from the interrupt
- * handler, it is safe to notify (send signal) right here because
- * we do not hold any runqueue locks needed by send_sig_info().
- *
- * However when coming from ctxsw, we cannot send the signal here.
- * It must be deferred until we are sure we do not hold any runqueue
- * related locks. The current task maybe different from the owner
- * only in UP mode. The deferral is implemented using the
- * TIF_NOTIFY_RESUME mechanism. In this case, the pending work
- * is checked when the task is about to leave the kernel (see
- * entry.S). As of this version of perfmon, a kernel only
- * task cannot be monitored in per-process mode. Therefore,
- * when this function gets called from pfm_load_regs(), we know
- * we have a user level task which will eventually either exit
- * or leave the kernel, and thereby go through the checkpoint
- * for TIF_*.
- */
- if (ctx->ctx_fl_system || mode == 0) {
- pfm_notify_user(ctx);
- ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_NONE;
- } else {
- struct thread_info *info;
+ if (ovfl_notify && ovfl_ctrl.notify_user) {
/*
- * given that TIF_NOTIFY_RESUME is not specific to
- * perfmon, we need to have a second level check to
- * verify the source of the notification.
+ * keep track of what to reset when unblocking
*/
- task->thread.pfm_ovfl_block_reset = 1;
+ ctx->ctx_ovfl_regs[0] = ovfl_pmds;
+
+ if (CTX_OVFL_NOBLOCK(ctx) == 0 && ovfl_ctrl.block) {
+
+ ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_BLOCK;
+
+ /*
+ * set the perfmon specific checking pending work
+ */
+ PFM_SET_WORK_PENDING(task, 1);
+
+ /*
+ * when coming from ctxsw, current still points to the
+ * previous task, therefore we must work with task and not current.
+ */
+ pfm_set_task_notify(task);
+ }
/*
- * when coming from ctxsw, current still points to the
- * previous task, therefore we must work with task and not current.
+ * defer until state is changed (shorten spin window). the context is locked
+ * anyway, so the signal receiver would come spin for nothing.
*/
- info = ((struct thread_info *) ((char *) task + IA64_TASK_SIZE));
- set_bit(TIF_NOTIFY_RESUME, &info->flags);
+ must_notify = 1;
}
+ DPRINT_ovfl(("current [%d] owner [%d] pending=%ld reason=%u ovfl_pmds=0x%lx ovfl_notify=0x%lx stopped=%d\n",
+ current->pid,
+ GET_PMU_OWNER() ? GET_PMU_OWNER()->pid : -1,
+ PFM_GET_WORK_PENDING(task),
+ ctx->ctx_fl_trap_reason,
+ ovfl_pmds,
+ ovfl_notify,
+ ovfl_ctrl.stop_monitoring ? 1 : 0));
+ /*
+ * in case monitoring must be stopped, we toggle the psr bits
+ */
+ if (ovfl_ctrl.stop_monitoring) {
+ pfm_mask_monitoring(task);
+ CTX_MASKED(ctx);
+ }
/*
- * keep the PMU frozen until either pfm_restart() or
- * task completes (non-blocking or notify_task gone).
+ * send notification now
*/
- ctx->ctx_fl_frozen = 1;
+ if (must_notify) pfm_ovfl_notify_user(ctx, ovfl_notify);
- DBprintk_ovfl(("current [%d] owner [%d] mode=%d return pmc0=0x%x must_block=%ld reason=%d\n",
- current->pid,
- PMU_OWNER() ? PMU_OWNER()->pid : -1,
- mode,
- ctx->ctx_fl_frozen ? 0x1 : 0x0,
- t->pfm_ovfl_block_reset,
- ctx->ctx_fl_trap_reason));
+ return;
+
+
+sanity_check:
+ printk(KERN_ERR "perfmon: CPU%d overflow handler [%d] pmc0=0x%lx\n",
+ smp_processor_id(),
+ task ? task->pid : -1,
+ pmc0);
+ return;
- preempt_enable_no_resched();
- return 0x1UL;
+stop_monitoring:
+ /*
+ * in SMP, zombie context is never restored but reclaimed in pfm_load_regs().
+ * Moreover, zombies are also reclaimed in pfm_save_regs(). Therefore we can
+ * come here as zombie only if the task is the current task. In which case, we
+ * can access the PMU hardware directly.
+ *
+ * Note that zombies do have PM_VALID set. So here we do the minimal.
+ *
+ * In case the context was zombified it could not be reclaimed at the time
+ * the monitoring program exited. At this point, the PMU reservation has been
+ * returned, the sampiing buffer has been freed. We must convert this call
+ * into a spurious interrupt. However, we must also avoid infinite overflows
+ * by stopping monitoring for this task. We can only come here for a per-task
+ * context. All we need to do is to stop monitoring using the psr bits which
+ * are always task private. By re-enabling secure montioring, we ensure that
+ * the monitored task will not be able to re-activate monitoring.
+ * The task will eventually be context switched out, at which point the context
+ * will be reclaimed (that includes releasing ownership of the PMU).
+ *
+ * So there might be a window of time where the number of per-task session is zero
+ * yet one PMU might have a owner and get at most one overflow interrupt for a zombie
+ * context. This is safe because if a per-task session comes in, it will push this one
+ * out and by the virtue on pfm_save_regs(), this one will disappear. If a system wide
+ * session is force on that CPU, given that we use task pinning, pfm_save_regs() will
+ * also push our zombie context out.
+ *
+ * Overall pretty hairy stuff....
+ */
+ DPRINT(("ctx is zombie for [%d], converted to spurious\n", task ? task->pid: -1));
+ pfm_clear_psr_up();
+ ia64_psr(regs)->up = 0;
+ ia64_psr(regs)->sp = 1;
+ return;
}
-static irqreturn_t
-pfm_interrupt_handler(int irq, void *arg, struct pt_regs *regs)
+static int
+pfm_do_interrupt_handler(int irq, void *arg, struct pt_regs *regs)
{
- u64 pmc0;
struct task_struct *task;
pfm_context_t *ctx;
+ unsigned long flags;
+ u64 pmc0;
+ int this_cpu = smp_processor_id();
+ int retval = 0;
- pfm_stats[get_cpu()].pfm_ovfl_intr_count++;
+ pfm_stats[this_cpu].pfm_ovfl_intr_count++;
/*
- * if an alternate handler is registered, just bypass the default one
- */
- if (pfm_alternate_intr_handler) {
- (*pfm_alternate_intr_handler->handler)(irq, arg, regs);
- put_cpu();
- return IRQ_HANDLED;
- }
-
- /*
* srlz.d done before arriving here
- *
- * This is slow
*/
- pmc0 = ia64_get_pmc(0);
+ pmc0 = ia64_get_pmc(0);
+
+ task = GET_PMU_OWNER();
+ ctx = GET_PMU_CTX();
/*
* if we have some pending bits set
- * assumes : if any PM[0].bit[63-1] is set, then PMC[0].fr = 1
+ * assumes : if any PMC0.bit[63-1] is set, then PMC0.fr = 1
*/
- if ((pmc0 & ~0x1UL)!=0UL && (task=PMU_OWNER())!= NULL) {
- /*
+ if (PMC0_HAS_OVFL(pmc0) && task) {
+ /*
* we assume that pmc0.fr is always set here
*/
- ctx = task->thread.pfm_context;
/* sanity check */
- if (!ctx) {
- printk(KERN_DEBUG "perfmon: Spurious overflow interrupt: process %d has "
- "no PFM context\n", task->pid);
- put_cpu();
- return IRQ_HANDLED;
- }
+ if (!ctx) goto report_spurious;
- /*
- * assume PMC[0].fr = 1 at this point
- */
- pmc0 = pfm_overflow_handler(0, task, ctx, pmc0, regs);
- /*
- * we can only update pmc0 when the overflow
- * is for the current context or we are in system
- * wide mode. In UP (per-task) the current
- * task may not be the one owning the PMU,
- * same thing for system-wide.
- */
- if (task == current || ctx->ctx_fl_system) {
- /*
- * We always clear the overflow status bits and either unfreeze
- * or keep the PMU frozen.
- */
- ia64_set_pmc(0, pmc0);
- ia64_srlz_d();
- } else {
- task->thread.pmc[0] = pmc0;
+ if (ctx->ctx_fl_system == 0 && (task->thread.flags & IA64_THREAD_PM_VALID) == 0) {
+ printk("perfmon: current [%d] owner = [%d] PMVALID=0 state=%d\n", current->pid, task->pid, ctx->ctx_state);
+ goto report_spurious;
}
+
+ PROTECT_CTX_NOPRINT(ctx, flags);
+
+ pfm_overflow_handler(task, ctx, pmc0, regs);
+
+ UNPROTECT_CTX_NOPRINT(ctx, flags);
+
} else {
- pfm_stats[smp_processor_id()].pfm_spurious_ovfl_intr_count++;
+ pfm_stats[this_cpu].pfm_spurious_ovfl_intr_count++;
+ retval = -1;
+ }
+ /*
+ * keep it unfrozen at all times
+ */
+ pfm_unfreeze_pmu();
+
+ return retval;
+
+report_spurious:
+ printk(KERN_INFO "perfmon: spurious overflow interrupt on CPU%d: process %d has no PFM context\n",
+ this_cpu, task->pid);
+ pfm_unfreeze_pmu();
+ return -1;
+}
+
+static pfm_irq_handler_t
+pfm_interrupt_handler(int irq, void *arg, struct pt_regs *regs)
+{
+ unsigned long m;
+ unsigned long min, max;
+ int this_cpu;
+ int ret;
+
+ this_cpu = smp_processor_id();
+ min = pfm_stats[this_cpu].pfm_ovfl_intr_cycles_min;
+ max = pfm_stats[this_cpu].pfm_ovfl_intr_cycles_max;
+
+ m = ia64_get_itc();
+
+ ret = pfm_do_interrupt_handler(irq, arg, regs);
+
+ m = ia64_get_itc() - m;
+
+ /*
+ * don't measure spurious interrupts
+ */
+ if (ret == 0) {
+ if (m < min) pfm_stats[this_cpu].pfm_ovfl_intr_cycles_min = m;
+ if (m > max) pfm_stats[this_cpu].pfm_ovfl_intr_cycles_max = m;
+ pfm_stats[this_cpu].pfm_ovfl_intr_cycles += m;
}
- put_cpu_no_resched();
- return IRQ_HANDLED;
+ PFM_IRQ_HANDLER_RET();
}
+
/* for debug only */
static int
pfm_proc_info(char *page)
{
char *p = page;
+ pfm_buffer_fmt_t *b;
+ unsigned long psr;
int i;
- p += sprintf(p, "fastctxsw : %s\n", pfm_sysctl.fastctxsw > 0 ? "Yes": "No");
- p += sprintf(p, "ovfl_mask : 0x%lx\n", pmu_conf.ovfl_val);
+ p += sprintf(p, "model : %s\n", pmu_conf.pmu_name);
+ p += sprintf(p, "fastctxsw : %s\n", pfm_sysctl.fastctxsw > 0 ? "Yes": "No");
+ p += sprintf(p, "ovfl_mask : 0x%lx\n", pmu_conf.ovfl_val);
for(i=0; i < NR_CPUS; i++) {
- if (cpu_online(i) == 0) continue;
- p += sprintf(p, "CPU%-2d overflow intrs : %lu\n", i, pfm_stats[i].pfm_ovfl_intr_count);
- p += sprintf(p, "CPU%-2d spurious intrs : %lu\n", i, pfm_stats[i].pfm_spurious_ovfl_intr_count);
- p += sprintf(p, "CPU%-2d recorded samples : %lu\n", i, pfm_stats[i].pfm_recorded_samples_count);
- p += sprintf(p, "CPU%-2d smpl buffer full : %lu\n", i, pfm_stats[i].pfm_full_smpl_buffer_count);
- p += sprintf(p, "CPU%-2d syst_wide : %d\n", i, per_cpu(pfm_syst_info, i) & PFM_CPUINFO_SYST_WIDE ? 1 : 0);
- p += sprintf(p, "CPU%-2d dcr_pp : %d\n", i, per_cpu(pfm_syst_info, i) & PFM_CPUINFO_DCR_PP ? 1 : 0);
- p += sprintf(p, "CPU%-2d exclude idle : %d\n", i, per_cpu(pfm_syst_info, i) & PFM_CPUINFO_EXCL_IDLE ? 1 : 0);
- p += sprintf(p, "CPU%-2d owner : %d\n", i, pmu_owners[i].owner ? pmu_owners[i].owner->pid: -1);
+ if (cpu_is_online(i) == 0) continue;
+ p += sprintf(p, "CPU%-2d overflow intrs : %lu\n", i, pfm_stats[i].pfm_ovfl_intr_count);
+ p += sprintf(p, "CPU%-2d overflow cycles : %lu\n", i, pfm_stats[i].pfm_ovfl_intr_cycles);
+ p += sprintf(p, "CPU%-2d overflow min : %lu\n", i, pfm_stats[i].pfm_ovfl_intr_cycles_min);
+ p += sprintf(p, "CPU%-2d overflow max : %lu\n", i, pfm_stats[i].pfm_ovfl_intr_cycles_max);
+ p += sprintf(p, "CPU%-2d smpl handler calls : %lu\n", i, pfm_stats[i].pfm_smpl_handler_calls);
+ p += sprintf(p, "CPU%-2d smpl handler cycles : %lu\n", i, pfm_stats[i].pfm_smpl_handler_cycles);
+ p += sprintf(p, "CPU%-2d spurious intrs : %lu\n", i, pfm_stats[i].pfm_spurious_ovfl_intr_count);
+ p += sprintf(p, "CPU%-2d sysupdt count : %lu\n", i, pfm_stats[i].pfm_sysupdt_count);
+ p += sprintf(p, "CPU%-2d sysupdt cycles : %lu\n", i, pfm_stats[i].pfm_sysupdt_cycles);
+ p += sprintf(p, "CPU%-2d syst_wide : %d\n" , i, pfm_get_cpu_data(pfm_syst_info, i) & PFM_CPUINFO_SYST_WIDE ? 1 : 0);
+ p += sprintf(p, "CPU%-2d dcr_pp : %d\n" , i, pfm_get_cpu_data(pfm_syst_info, i) & PFM_CPUINFO_DCR_PP ? 1 : 0);
+ p += sprintf(p, "CPU%-2d exclude idle : %d\n" , i, pfm_get_cpu_data(pfm_syst_info, i) & PFM_CPUINFO_EXCL_IDLE ? 1 : 0);
+ p += sprintf(p, "CPU%-2d owner : %d\n" , i, pfm_get_cpu_data(pmu_owner, i) ? pfm_get_cpu_data(pmu_owner, i)->pid: -1);
+ p += sprintf(p, "CPU%-2d context : %p\n" , i, pfm_get_cpu_data(pmu_ctx, i));
+ p += sprintf(p, "CPU%-2d activations : %lu\n", i, pfm_get_cpu_data(pmu_activation_number,i));
}
- LOCK_PFS();
+ if (hweight64(PFM_CPU_ONLINE_MAP) == 1)
+ {
+ psr = pfm_get_psr();
+ ia64_srlz_d();
+ p += sprintf(p, "CPU%-2d psr : 0x%lx\n", smp_processor_id(), psr);
+ p += sprintf(p, "CPU%-2d pmc0 : 0x%lx\n", smp_processor_id(), ia64_get_pmc(0));
+ for(i=4; i < 8; i++) {
+ p += sprintf(p, "CPU%-2d pmc%u : 0x%lx\n", smp_processor_id(), i, ia64_get_pmc(i));
+ p += sprintf(p, "CPU%-2d pmd%u : 0x%lx\n", smp_processor_id(), i, ia64_get_pmd(i));
+ }
+ }
- p += sprintf(p, "proc_sessions : %u\n"
- "sys_sessions : %u\n"
- "sys_use_dbregs : %u\n"
- "ptrace_use_dbregs : %u\n",
- pfm_sessions.pfs_task_sessions,
+ LOCK_PFS();
+ p += sprintf(p, "proc_sessions : %u\n"
+ "sys_sessions : %u\n"
+ "sys_use_dbregs : %u\n"
+ "ptrace_use_dbregs : %u\n",
+ pfm_sessions.pfs_task_sessions,
pfm_sessions.pfs_sys_sessions,
pfm_sessions.pfs_sys_use_dbregs,
pfm_sessions.pfs_ptrace_use_dbregs);
-
UNLOCK_PFS();
+ LOCK_BUF_FMT_LIST();
+
+ for (b = pfm_buffer_fmt_list; b ; b = b->fmt_next) {
+ p += sprintf(p, "format : %02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x %s\n",
+ b->fmt_uuid[0],
+ b->fmt_uuid[1],
+ b->fmt_uuid[2],
+ b->fmt_uuid[3],
+ b->fmt_uuid[4],
+ b->fmt_uuid[5],
+ b->fmt_uuid[6],
+ b->fmt_uuid[7],
+ b->fmt_uuid[8],
+ b->fmt_uuid[9],
+ b->fmt_uuid[10],
+ b->fmt_uuid[11],
+ b->fmt_uuid[12],
+ b->fmt_uuid[13],
+ b->fmt_uuid[14],
+ b->fmt_uuid[15],
+ b->fmt_name);
+ }
+ UNLOCK_BUF_FMT_LIST();
+
return p - page;
}
}
/*
- * we come here as soon as PFM_CPUINFO_SYST_WIDE is set. This happens
+ * we come here as soon as local_cpu_data->pfm_syst_wide is set. this happens
* during pfm_enable() hence before pfm_start(). We cannot assume monitoring
- * is active or inactive based on mode. We must rely on the value in
- * cpu_data(i)->pfm_syst_info
+ * is active or inactive based on mode. We must rely on the value in
+ * local_cpu_data->pfm_syst_info
*/
void
-pfm_syst_wide_update_task(struct task_struct *task, unsigned long info, int is_ctxswin)
+pfm_do_syst_wide_update_task(struct task_struct *task, unsigned long info, int is_ctxswin)
{
struct pt_regs *regs;
unsigned long dcr;
unsigned long dcr_pp;
- preempt_disable();
dcr_pp = info & PFM_CPUINFO_DCR_PP ? 1 : 0;
/*
- * pid 0 is guaranteed to be the idle task. There is one such task with pid 0
+ * pid 0 is guaranteed to be the idle task. There is one such task with pid 0
* on every CPU, so we can rely on the pid to identify the idle task.
*/
if ((info & PFM_CPUINFO_EXCL_IDLE) == 0 || task->pid) {
- regs = (struct pt_regs *)((unsigned long) task + IA64_STK_OFFSET);
- regs--;
+ regs = ia64_task_regs(task);
ia64_psr(regs)->pp = is_ctxswin ? dcr_pp : 0;
- preempt_enable();
return;
}
/*
*/
if (dcr_pp) {
dcr = ia64_get_dcr();
- /*
- * context switching in?
+ /*
+ * context switching in?
*/
if (is_ctxswin) {
/* mask monitoring for the idle task */
ia64_set_dcr(dcr & ~IA64_DCR_PP);
pfm_clear_psr_pp();
ia64_srlz_i();
- preempt_enable();
return;
}
- /*
+ /*
* context switching out
- * restore monitoring for next task
+ * restore monitoring for next task
*
- * Due to inlining this odd if-then-else construction generates
+ * Due to inlining this odd if-then-else construction generates
* better code.
*/
ia64_set_dcr(dcr |IA64_DCR_PP);
pfm_set_psr_pp();
ia64_srlz_i();
}
- preempt_enable();
}
void
-pfm_save_regs (struct task_struct *task)
+pfm_syst_wide_update_task(struct task_struct *task, unsigned long info, int is_ctxswin)
{
- pfm_context_t *ctx;
- unsigned long mask;
- u64 psr;
- int i;
-
- preempt_disable();
-
- ctx = task->thread.pfm_context;
-
-
- /*
- * save current PSR: needed because we modify it
- */
- psr = pfm_get_psr();
-
- /*
- * stop monitoring:
- * This is the last instruction which can generate an overflow
- *
- * We do not need to set psr.sp because, it is irrelevant in kernel.
- * It will be restored from ipsr when going back to user level
- */
- pfm_clear_psr_up();
- ia64_srlz_i();
-
- ctx->ctx_saved_psr = psr;
-
-#ifdef CONFIG_SMP
- /*
- * We do not use a lazy scheme in SMP because
- * of the new scheduler which masks interrupts
- * during low-level context switch. So we save
- * all the PMD register we use and restore on
- * ctxsw in.
- *
- * release ownership of this PMU.
- * must be done before we save the registers.
- */
- SET_PMU_OWNER(NULL);
-
- /*
- * save PMDs
- */
- ia64_srlz_d();
-
- mask = ctx->ctx_used_pmds[0];
- for (i=0; mask; i++, mask>>=1) {
- if (mask & 0x1) task->thread.pmd[i] =ia64_get_pmd(i);
- }
-
- /*
- * save pmc0
- */
- task->thread.pmc[0] = ia64_get_pmc(0);
-
- /*
- * force a full reload
- */
- atomic_set(&ctx->ctx_last_cpu, -1);
-#endif
- preempt_enable();
+ unsigned long start, end;
+ pfm_stats[smp_processor_id()].pfm_sysupdt_count++;
+ start = ia64_get_itc();
+ pfm_do_syst_wide_update_task(task, info, is_ctxswin);
+ end = ia64_get_itc();
+ pfm_stats[smp_processor_id()].pfm_sysupdt_cycles += end-start;
}
-static void
-pfm_lazy_save_regs (struct task_struct *task)
+#ifdef CONFIG_SMP
+void
+pfm_save_regs(struct task_struct *task)
{
pfm_context_t *ctx;
- struct thread_struct *t;
- unsigned long mask;
- int i;
-
- preempt_disable();
- DBprintk(("on [%d] by [%d]\n", task->pid, current->pid));
-
- t = &task->thread;
- ctx = task->thread.pfm_context;
-
- /*
- * do not own the PMU
- */
- SET_PMU_OWNER(NULL);
+ struct thread_struct *t;
+ unsigned long flags;
+ u64 psr;
- ia64_srlz_d();
+ ctx = PFM_GET_CTX(task);
+ if (ctx == NULL) goto save_error;
+ t = &task->thread;
/*
- * XXX needs further optimization.
- * Also must take holes into account
+ * we always come here with interrupts ALREADY disabled by
+ * the scheduler. So we simply need to protect against concurrent
+ * access, not CPU concurrency.
*/
- mask = ctx->ctx_used_pmds[0];
- for (i=0; mask; i++, mask>>=1) {
- if (mask & 0x1) t->pmd[i] =ia64_get_pmd(i);
- }
+ flags = pfm_protect_ctx_ctxsw(ctx);
- /* save pmc0 */
- t->pmc[0] = ia64_get_pmc(0);
+ if (CTX_IS_ZOMBIE(ctx)) {
+ struct pt_regs *regs = ia64_task_regs(task);
- /* not owned by this CPU */
- atomic_set(&ctx->ctx_last_cpu, -1);
- preempt_enable();
-}
+ pfm_clear_psr_up();
-void
-pfm_load_regs (struct task_struct *task)
-{
- struct thread_struct *t;
- pfm_context_t *ctx;
- struct task_struct *owner;
- unsigned long mask;
- u64 psr;
- int i;
+ DPRINT(("ctx zombie, forcing cleanup for [%d]\n", task->pid));
- preempt_disable();
+ pfm_force_cleanup(ctx, regs);
- owner = PMU_OWNER();
- ctx = task->thread.pfm_context;
- t = &task->thread;
+ BUG_ON(ctx->ctx_smpl_hdr);
- if (ctx == NULL) {
- preempt_enable();
- printk("perfmon: pfm_load_regs: null ctx for [%d]\n", task->pid);
+ pfm_unprotect_ctx_ctxsw(ctx, flags);
+
+ pfm_context_free(ctx);
return;
}
/*
- * we restore ALL the debug registers to avoid picking up
- * stale state.
- *
- * This must be done even when the task is still the owner
- * as the registers may have been modified via ptrace()
- * (not perfmon) by the previous task.
- *
- * XXX: dealing with this in a lazy fashion requires modifications
- * to the way the the debug registers are managed. This is will done
- * in the next version of perfmon.
+ * sanity check
*/
- if (ctx->ctx_fl_using_dbreg) {
- for (i=0; i < (int) pmu_conf.num_ibrs; i++) {
- ia64_set_ibr(i, t->ibr[i]);
- }
- ia64_srlz_i();
- for (i=0; i < (int) pmu_conf.num_dbrs; i++) {
- ia64_set_dbr(i, t->dbr[i]);
- }
- ia64_srlz_d();
- }
+ if (ctx->ctx_last_activation != GET_ACTIVATION()) {
+ DPRINT(("ctx_activation=%lu activation=%lu state=%d: no save\n",
+ ctx->ctx_last_activation,
+ GET_ACTIVATION(), ctx->ctx_state));
- /*
- * if we were the last user, then nothing to do except restore psr
- * this path cannot be used in SMP
- */
- if (owner == task) {
- if ((unsigned int) atomic_read(&ctx->ctx_last_cpu) != smp_processor_id())
- DBprintk(("invalid last_cpu=%d for [%d]\n",
- atomic_read(&ctx->ctx_last_cpu), task->pid));
+ pfm_unprotect_ctx_ctxsw(ctx, flags);
- psr = ctx->ctx_saved_psr;
- pfm_set_psr_l(psr);
- preempt_enable();
return;
}
/*
- * someone else is still using the PMU, first push it out and
- * then we'll be able to install our stuff !
- *
- * not possible in SMP
+ * save current PSR: needed because we modify it
*/
- if (owner) pfm_lazy_save_regs(owner);
+ psr = pfm_get_psr();
/*
- * To avoid leaking information to the user level when psr.sp=0,
- * we must reload ALL implemented pmds (even the ones we don't use).
- * In the kernel we only allow PFM_READ_PMDS on registers which
- * we initialized or requested (sampling) so there is no risk there.
+ * stop monitoring:
+ * This is the last instruction which may generate an overflow
*
- * As an optimization, we will only reload the PMD that we use when
- * the context is in protected mode, i.e. psr.sp=1 because then there
- * is no leak possible.
+ * We do not need to set psr.sp because, it is irrelevant in kernel.
+ * It will be restored from ipsr when going back to user level
*/
- mask = pfm_sysctl.fastctxsw || ctx->ctx_fl_protected ? ctx->ctx_used_pmds[0] : ctx->ctx_reload_pmds[0];
- for (i=0; mask; i++, mask>>=1) {
- if (mask & 0x1) ia64_set_pmd(i, t->pmd[i] & pmu_conf.ovfl_val);
- }
-
- /*
- * PMC0 is never set in the mask because it is always restored
- * separately.
- *
- * ALL PMCs are systematically reloaded, unused registers
- * get their default (PAL reset) values to avoid picking up
- * stale configuration.
- */
- mask = ctx->ctx_reload_pmcs[0];
- for (i=0; mask; i++, mask>>=1) {
- if (mask & 0x1) ia64_set_pmc(i, t->pmc[i]);
- }
+ pfm_clear_psr_up();
/*
- * manually invoke core interrupt handler
- * if the task had a pending overflow when it was ctxsw out.
- * Side effect on ctx_fl_frozen is possible.
+ * keep a copy of the saved psr (for reload)
*/
- if (t->pmc[0] & ~0x1) {
- t->pmc[0] = pfm_overflow_handler(1, task, ctx, t->pmc[0], NULL);
- }
+ ctx->ctx_saved_psr = psr;
/*
- * unfreeze PMU if possible
+ * release ownership of this PMU.
+ * PM interrupts are masked, so nothing
+ * can happen.
*/
- if (ctx->ctx_fl_frozen == 0) pfm_unfreeze_pmu();
-
- atomic_set(&ctx->ctx_last_cpu, smp_processor_id());
-
- SET_PMU_OWNER(task);
+ SET_PMU_OWNER(NULL, NULL);
/*
- * restore the psr we changed in pfm_save_regs()
+ * we systematically save the PMD as we have no
+ * guarantee we will be schedule at that same
+ * CPU again.
*/
- psr = ctx->ctx_saved_psr;
- preempt_enable();
- pfm_set_psr_l(psr);
-}
-
-/*
- * XXX: make this routine able to work with non current context
- */
-static void
-pfm_reset_pmu(struct task_struct *task)
-{
- struct thread_struct *t = &task->thread;
- pfm_context_t *ctx = t->pfm_context;
- int i;
-
- if (task != current) {
- printk("perfmon: invalid task in pfm_reset_pmu()\n");
- return;
- }
- preempt_disable();
-
- /* Let's make sure the PMU is frozen */
- pfm_freeze_pmu();
+ pfm_save_pmds(t->pmds, ctx->ctx_used_pmds[0]);
/*
- * install reset values for PMC. We skip PMC0 (done above)
- * XX: good up to 64 PMCS
+ * save pmc0 ia64_srlz_d() done in pfm_save_pmds()
+ * we will need it on the restore path to check
+ * for pending overflow.
*/
- for (i=1; (pmu_conf.pmc_desc[i].type & PFM_REG_END) == 0; i++) {
- if ((pmu_conf.pmc_desc[i].type & PFM_REG_IMPL) == 0) continue;
- ia64_set_pmc(i, PMC_DFL_VAL(i));
- /*
- * When restoring context, we must restore ALL pmcs, even the ones
- * that the task does not use to avoid leaks and possibly corruption
- * of the sesion because of configuration conflicts. So here, we
- * initialize the entire set used in the context switch restore routine.
- */
- t->pmc[i] = PMC_DFL_VAL(i);
- DBprintk(("pmc[%d]=0x%lx\n", i, t->pmc[i]));
- }
+ t->pmcs[0] = ia64_get_pmc(0);
/*
- * clear reset values for PMD.
- * XXX: good up to 64 PMDS.
+ * unfreeze PMU if had pending overflows
*/
- for (i=0; (pmu_conf.pmd_desc[i].type & PFM_REG_END) == 0; i++) {
- if ((pmu_conf.pmd_desc[i].type & PFM_REG_IMPL) == 0) continue;
- ia64_set_pmd(i, 0UL);
- t->pmd[i] = 0UL;
- }
+ if (t->pmcs[0] & ~1UL) pfm_unfreeze_pmu();
/*
- * On context switched restore, we must restore ALL pmc and ALL pmd even
- * when they are not actively used by the task. In UP, the incoming process
- * may otherwise pick up left over PMC, PMD state from the previous process.
- * As opposed to PMD, stale PMC can cause harm to the incoming
- * process because they may change what is being measured.
- * Therefore, we must systematically reinstall the entire
- * PMC state. In SMP, the same thing is possible on the
- * same CPU but also on between 2 CPUs.
- *
- * The problem with PMD is information leaking especially
- * to user level when psr.sp=0
- *
- * There is unfortunately no easy way to avoid this problem
- * on either UP or SMP. This definitively slows down the
- * pfm_load_regs() function.
- */
-
- /*
- * We must include all the PMC in this mask to make sure we don't
- * see any side effect of a stale state, such as opcode matching
- * or range restrictions, for instance.
- *
- * We never directly restore PMC0 so we do not include it in the mask.
- */
- ctx->ctx_reload_pmcs[0] = pmu_conf.impl_pmcs[0] & ~0x1;
- /*
- * We must include all the PMD in this mask to avoid picking
- * up stale value and leak information, especially directly
- * at the user level when psr.sp=0
- */
- ctx->ctx_reload_pmds[0] = pmu_conf.impl_pmds[0];
-
- /*
- * Keep track of the pmds we want to sample
- * XXX: may be we don't need to save/restore the DEAR/IEAR pmds
- * but we do need the BTB for sure. This is because of a hardware
- * buffer of 1 only for non-BTB pmds.
- *
- * We ignore the unimplemented pmds specified by the user
+ * finally, unmask interrupts and allow context
+ * access.
+ * Any pended overflow interrupt may be delivered
+ * here and will be treated as spurious because we
+ * have have no PMU owner anymore.
*/
- ctx->ctx_used_pmds[0] = ctx->ctx_smpl_regs[0];
- ctx->ctx_used_pmcs[0] = 1; /* always save/restore PMC[0] */
+ pfm_unprotect_ctx_ctxsw(ctx, flags);
- /*
- * useful in case of re-enable after disable
- */
- ctx->ctx_used_ibrs[0] = 0UL;
- ctx->ctx_used_dbrs[0] = 0UL;
+ return;
- ia64_srlz_d();
- preempt_enable();
+save_error:
+ printk(KERN_ERR "perfmon: pfm_save_regs CPU%d [%d] NULL context PM_VALID=%ld\n",
+ smp_processor_id(), task->pid,
+ task->thread.flags & IA64_THREAD_PM_VALID);
}
+#else /* !CONFIG_SMP */
+
/*
- * This function is called when a thread exits (from exit_thread()).
- * This is a simplified pfm_save_regs() that simply flushes the current
- * register state into the save area taking into account any pending
- * overflow. This time no notification is sent because the task is dying
- * anyway. The inline processing of overflows avoids loosing some counts.
- * The PMU is frozen on exit from this call and is to never be reenabled
- * again for this task.
- *
+ * in 2.5, interrupts are masked when we come here
*/
void
-pfm_flush_regs (struct task_struct *task)
+pfm_save_regs(struct task_struct *task)
{
pfm_context_t *ctx;
- u64 pmc0;
- unsigned long mask2, val;
- int i;
-
- ctx = task->thread.pfm_context;
+ u64 psr;
- if (ctx == NULL) return;
+ ctx = PFM_GET_CTX(task);
+ if (ctx == NULL) goto save_error;
- /*
- * that's it if context already disabled
+ /*
+ * save current PSR: needed because we modify it
*/
- if (ctx->ctx_flags.state == PFM_CTX_DISABLED) return;
+ psr = pfm_get_psr();
- preempt_disable();
/*
* stop monitoring:
- * This is the only way to stop monitoring without destroying overflow
- * information in PMC[0].
- * This is the last instruction which can cause overflow when monitoring
- * in kernel.
- * By now, we could still have an overflow interrupt in-flight.
+ * This is the last instruction which may generate an overflow
+ *
+ * We do not need to set psr.sp because, it is irrelevant in kernel.
+ * It will be restored from ipsr when going back to user level
*/
- if (ctx->ctx_fl_system) {
-
+ pfm_clear_psr_up();
- /* disable dcr pp */
- ia64_set_dcr(ia64_get_dcr() & ~IA64_DCR_PP);
+ /*
+ * keep a copy of the saved psr (for reload)
+ */
+ ctx->ctx_saved_psr = psr;
- /* stop monitoring */
- pfm_clear_psr_pp();
+ psr = pfm_get_psr();
+ if (psr & IA64_PSR_UP) {
+ printk(KERN_ERR " perfmon: pfm_save_regs: psr.up set current [%d] owner [%d] psr=0x%lx\n", current->pid, GET_PMU_OWNER()->pid, psr);
+ }
+ if (psr & IA64_PSR_I) {
+ printk(KERN_ERR " perfmon: pfm_save_regs: psr.i set current [%d] owner [%d] psr=0x%lx\n", current->pid, GET_PMU_OWNER()->pid, psr);
+ }
- ia64_srlz_i();
+ return;
+save_error:
+ printk(KERN_ERR "perfmon: pfm_save_regs CPU%d [%d] NULL context PM_VALID=%ld\n",
+ smp_processor_id(), task->pid,
+ task->thread.flags & IA64_THREAD_PM_VALID);
+}
- PFM_CPUINFO_CLEAR(PFM_CPUINFO_SYST_WIDE);
- PFM_CPUINFO_CLEAR(PFM_CPUINFO_DCR_PP);
- PFM_CPUINFO_CLEAR(PFM_CPUINFO_EXCL_IDLE);
- } else {
+static void
+pfm_lazy_save_regs (struct task_struct *task)
+{
+ pfm_context_t *ctx;
+ struct thread_struct *t;
+ unsigned long flags;
+ unsigned long psr;
- /* stop monitoring */
+#if 1
+ psr = pfm_get_psr();
+ if (psr & IA64_PSR_UP) {
+ printk(KERN_ERR " perfmon: pfm_lazy_save_regs: psr.up set current [%d] owner [%d] psr=0x%lx\n", current->pid, task->pid, psr);
pfm_clear_psr_up();
-
- ia64_srlz_i();
-
- /* no more save/restore on ctxsw */
- current->thread.flags &= ~IA64_THREAD_PM_VALID;
}
+#endif
- /*
- * Mark the PMU as not owned
- * This will cause the interrupt handler to do nothing in case an overflow
- * interrupt was in-flight
- * This also guarantees that pmc0 will contain the final state
- * It virtually gives us full control on overflow processing from that point
- * on.
- * It must be an atomic operation.
- */
- SET_PMU_OWNER(NULL);
+ ctx = PFM_GET_CTX(task);
+ t = &task->thread;
+
+ DPRINT(("on [%d] used_pmds=0x%lx\n", task->pid, ctx->ctx_used_pmds[0]));
/*
- * read current overflow status:
+ * we need to mask PMU overflow here to
+ * make sure that we maintain pmc0 until
+ * we save it. overflow interrupts are
+ * treated as spurious if there is no
+ * owner.
*
- * we are guaranteed to read the final stable state
+ * XXX: I don't think this is necessary
*/
- ia64_srlz_d();
- pmc0 = ia64_get_pmc(0); /* slow */
+ PROTECT_CTX(ctx,flags);
/*
- * freeze PMU:
+ * release ownership of this PMU.
+ * must be done before we save the registers.
*
- * This destroys the overflow information. This is required to make sure
- * next process does not start with monitoring on if not requested
+ * after this call any PMU interrupt is treated
+ * as spurious.
*/
- pfm_freeze_pmu();
+ SET_PMU_OWNER(NULL, NULL);
/*
- * We don't need to restore psr, because we are on our way out
+ * save all the pmds we use
*/
+ pfm_save_pmds(t->pmds, ctx->ctx_used_pmds[0]);
/*
- * This loop flushes the PMD into the PFM context.
- * It also processes overflow inline.
- *
- * IMPORTANT: No notification is sent at this point as the process is dying.
- * The implicit notification will come from a SIGCHILD or a return from a
- * waitpid().
- *
+ * save pmc0 ia64_srlz_d() done in pfm_save_pmds()
+ * it is needed to check for pended overflow
+ * on the restore path
*/
-
- if ((unsigned int) atomic_read(&ctx->ctx_last_cpu) != smp_processor_id())
- printk(KERN_DEBUG "perfmon: [%d] last_cpu=%d\n",
- task->pid, atomic_read(&ctx->ctx_last_cpu));
+ t->pmcs[0] = ia64_get_pmc(0);
/*
- * we save all the used pmds
- * we take care of overflows for pmds used as counters
+ * unfreeze PMU if had pending overflows
*/
- mask2 = ctx->ctx_used_pmds[0];
- for (i = 0; mask2; i++, mask2>>=1) {
-
- /* skip non used pmds */
- if ((mask2 & 0x1) == 0) continue;
+ if (t->pmcs[0] & ~1UL) pfm_unfreeze_pmu();
- val = ia64_get_pmd(i);
-
- if (PMD_IS_COUNTING(i)) {
- DBprintk(("[%d] pmd[%d] soft_pmd=0x%lx hw_pmd=0x%lx\n",
- task->pid,
- i,
- ctx->ctx_soft_pmds[i].val,
- val & pmu_conf.ovfl_val));
-
- /* collect latest results */
- ctx->ctx_soft_pmds[i].val += val & pmu_conf.ovfl_val;
-
- /*
- * now everything is in ctx_soft_pmds[] and we need
- * to clear the saved context from save_regs() such that
- * pfm_read_pmds() gets the correct value
- */
- task->thread.pmd[i] = 0;
-
- /*
- * take care of overflow inline
- */
- if (pmc0 & (1UL << i)) {
- ctx->ctx_soft_pmds[i].val += 1 + pmu_conf.ovfl_val;
- DBprintk(("[%d] pmd[%d] overflowed soft_pmd=0x%lx\n",
- task->pid, i, ctx->ctx_soft_pmds[i].val));
- }
- } else {
- DBprintk(("[%d] pmd[%d] hw_pmd=0x%lx\n", task->pid, i, val));
- /*
- * not a counter, just save value as is
- */
- task->thread.pmd[i] = val;
- }
- }
- /*
- * indicates that context has been saved
+ /*
+ * now get can unmask PMU interrupts, they will
+ * be treated as purely spurious and we will not
+ * lose any information
*/
- atomic_set(&ctx->ctx_last_cpu, -1);
- preempt_enable();
+ UNPROTECT_CTX(ctx,flags);
}
+#endif /* CONFIG_SMP */
-
-/*
- * task is the newly created task, pt_regs for new child
- */
-int
-pfm_inherit(struct task_struct *task, struct pt_regs *regs)
+#ifdef CONFIG_SMP
+void
+pfm_load_regs (struct task_struct *task)
{
pfm_context_t *ctx;
- pfm_context_t *nctx;
- struct thread_struct *thread;
- unsigned long m;
- int i;
-
- /*
- * the new task was copied from parent and therefore points
- * to the parent's context at this point
- */
- ctx = task->thread.pfm_context;
- thread = &task->thread;
+ struct thread_struct *t;
+ struct task_struct *owner;
+ unsigned long pmc_mask = 0UL, pmd_mask = 0UL;
+ unsigned long flags;
+ u64 psr;
- preempt_disable();
- /*
- * for secure sessions, make sure child cannot mess up
- * the monitoring session.
- */
- if (ctx->ctx_fl_unsecure == 0) {
- ia64_psr(regs)->sp = 1;
- DBprintk(("enabling psr.sp for [%d]\n", task->pid));
- } else {
- DBprintk(("psr.sp=%d [%d]\n", ia64_psr(regs)->sp, task->pid));
+ ctx = PFM_GET_CTX(task);
+ if (unlikely(ctx == NULL)) {
+ printk(KERN_ERR "perfmon: pfm_load_regs() null context\n");
+ return;
}
- /*
- * if there was a virtual mapping for the sampling buffer
- * the mapping is NOT inherited across fork() (see VM_DONTCOPY),
- * so we don't have to explicitly remove it here.
- *
- *
- * Part of the clearing of fields is also done in
- * copy_thread() because the fiels are outside the
- * pfm_context structure and can affect tasks not
- * using perfmon.
- */
+ owner = GET_PMU_OWNER();
+ t = &task->thread;
+
+#if 1
+ psr = pfm_get_psr();
+ BUG_ON(psr & IA64_PSR_UP);
+ psr = pfm_get_psr();
+ BUG_ON(psr & IA64_PSR_I);
+#endif
- /* clear pending notification */
- task->thread.pfm_ovfl_block_reset = 0;
/*
- * clear cpu pinning restriction for child
+ * possible on unload
*/
- if (ctx->ctx_fl_system) {
- set_cpus_allowed(task, ctx->ctx_saved_cpus_allowed);
-
- DBprintk(("setting cpus_allowed for [%d] to 0x%lx from 0x%lx\n",
- task->pid,
- ctx->ctx_saved_cpus_allowed,
- current->cpus_allowed));
+ if (unlikely((t->flags & IA64_THREAD_PM_VALID) == 0)) {
+ DPRINT(("[%d] PM_VALID=0, nothing to do\n", task->pid));
+ return;
}
/*
- * takes care of easiest case first
+ * we always come here with interrupts ALREADY disabled by
+ * the scheduler. So we simply need to protect against concurrent
+ * access, not CPU concurrency.
*/
- if (CTX_INHERIT_MODE(ctx) == PFM_FL_INHERIT_NONE) {
+ flags = pfm_protect_ctx_ctxsw(ctx);
- DBprintk(("removing PFM context for [%d]\n", task->pid));
+ if (unlikely(CTX_IS_ZOMBIE(ctx))) {
+ struct pt_regs *regs = ia64_task_regs(task);
- task->thread.pfm_context = NULL;
+ BUG_ON(ctx->ctx_smpl_hdr);
- /*
- * we must clear psr.up because the new child does
- * not have a context and the PM_VALID flag is cleared
- * in copy_thread().
- *
- * we do not clear psr.pp because it is always
- * controlled by the system wide logic and we should
- * never be here when system wide is running anyway
- */
- ia64_psr(regs)->up = 0;
+ DPRINT(("ctx zombie, forcing cleanup for [%d]\n", task->pid));
- preempt_enable();
+ pfm_force_cleanup(ctx, regs);
- /* copy_thread() clears IA64_THREAD_PM_VALID */
- return 0;
- }
- nctx = pfm_context_alloc();
- if (nctx == NULL) return -ENOMEM;
+ pfm_unprotect_ctx_ctxsw(ctx, flags);
- /* copy content */
- *nctx = *ctx;
+ /*
+ * this one (kmalloc'ed) is fine with interrupts disabled
+ */
+ pfm_context_free(ctx);
+ return;
+ }
- if (CTX_INHERIT_MODE(ctx) == PFM_FL_INHERIT_ONCE) {
- nctx->ctx_fl_inherit = PFM_FL_INHERIT_NONE;
- DBprintk(("downgrading to INHERIT_NONE for [%d]\n", task->pid));
+ /*
+ * we restore ALL the debug registers to avoid picking up
+ * stale state.
+ *
+ * This must be done even when the task is still the owner
+ * as the registers may have been modified via ptrace()
+ * (not perfmon) by the previous task.
+ */
+ if (ctx->ctx_fl_using_dbreg) {
+ pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf.num_ibrs);
+ pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf.num_dbrs);
}
/*
- * task is not yet visible in the tasklist, so we do
- * not need to lock the newly created context.
- * However, we must grab the tasklist_lock to ensure
- * that the ctx_owner or ctx_notify_task do not disappear
- * while we increment their check counters.
+ * retrieve saved psr
*/
- read_lock(&tasklist_lock);
+ psr = ctx->ctx_saved_psr;
- if (nctx->ctx_notify_task)
- atomic_inc(&nctx->ctx_notify_task->thread.pfm_notifiers_check);
+ /*
+ * if we were the last user of the PMU on that CPU,
+ * then nothing to do except restore psr
+ */
+ if (GET_LAST_CPU(ctx) == smp_processor_id() && ctx->ctx_last_activation == GET_ACTIVATION()) {
- if (nctx->ctx_owner)
- atomic_inc(&nctx->ctx_owner->thread.pfm_owners_check);
+ /*
+ * retrieve partial reload masks (due to user modifications)
+ */
+ pmc_mask = ctx->ctx_reload_pmcs[0];
+ pmd_mask = ctx->ctx_reload_pmds[0];
- read_unlock(&tasklist_lock);
+ if (pmc_mask || pmd_mask) DPRINT(("partial reload [%d] pmd_mask=0x%lx pmc_mask=0x%lx\n", task->pid, pmd_mask, pmc_mask));
+ } else {
+ /*
+ * To avoid leaking information to the user level when psr.sp=0,
+ * we must reload ALL implemented pmds (even the ones we don't use).
+ * In the kernel we only allow PFM_READ_PMDS on registers which
+ * we initialized or requested (sampling) so there is no risk there.
+ */
+ pmd_mask = pfm_sysctl.fastctxsw ? ctx->ctx_used_pmds[0] : ctx->ctx_all_pmds[0];
+ /*
+ * ALL accessible PMCs are systematically reloaded, unused registers
+ * get their default (from pfm_reset_pmu_state()) values to avoid picking
+ * up stale configuration.
+ *
+ * PMC0 is never in the mask. It is always restored separately.
+ */
+ pmc_mask = ctx->ctx_all_pmcs[0];
- LOCK_PFS();
- pfm_sessions.pfs_task_sessions++;
- UNLOCK_PFS();
+ DPRINT(("full reload for [%d] owner=%d activation=%lu last_activation=%lu last_cpu=%d pmd_mask=0x%lx pmc_mask=0x%lx\n",
+ task->pid, owner ? owner->pid : -1,
+ GET_ACTIVATION(), ctx->ctx_last_activation,
+ GET_LAST_CPU(ctx), pmd_mask, pmc_mask));
- /* initialize counters in new context */
- m = nctx->ctx_used_pmds[0] >> PMU_FIRST_COUNTER;
- for(i = PMU_FIRST_COUNTER ; m ; m>>=1, i++) {
- if ((m & 0x1) && pmu_conf.pmd_desc[i].type == PFM_REG_COUNTING) {
- nctx->ctx_soft_pmds[i].val = nctx->ctx_soft_pmds[i].lval & ~pmu_conf.ovfl_val;
- thread->pmd[i] = nctx->ctx_soft_pmds[i].lval & pmu_conf.ovfl_val;
- } else {
- thread->pmd[i] = 0UL; /* reset to initial state */
- }
}
-
- nctx->ctx_fl_frozen = 0;
- nctx->ctx_ovfl_regs[0] = 0UL;
- nctx->ctx_fl_trap_reason = PFM_TRAP_REASON_NONE;
- atomic_set(&nctx->ctx_last_cpu, -1);
-
/*
- * here nctx->ctx_psb == ctx->ctx_psb
+ * when context is MASKED, we will restore PMC with plm=0
+ * and PMD with stale information, but that's ok, nothing
+ * will be captured.
*
- * increment reference count to sampling
- * buffer, if any. Note that this is independent
- * from the virtual mapping. The latter is never
- * inherited while the former will be if context
- * is setup to something different from PFM_FL_INHERIT_NONE
+ * XXX: optimize here
*/
- if (nctx->ctx_psb) {
- LOCK_PSB(nctx->ctx_psb);
+ if (pmd_mask) pfm_restore_pmds(t->pmds, pmd_mask);
+ if (pmc_mask) pfm_restore_pmcs(t->pmcs, pmc_mask);
- nctx->ctx_psb->psb_refcnt++;
-
- DBprintk(("updated smpl @ %p refcnt=%lu psb_flags=0x%x\n",
- ctx->ctx_psb->psb_hdr,
- ctx->ctx_psb->psb_refcnt,
- ctx->ctx_psb->psb_flags));
-
- UNLOCK_PSB(nctx->ctx_psb);
-
- /*
- * remove any pointer to sampling buffer mapping
- */
- nctx->ctx_smpl_vaddr = 0;
+ /*
+ * check for pending overflow at the time the state
+ * was saved.
+ */
+ if (unlikely(PMC0_HAS_OVFL(t->pmcs[0]))) {
+ struct pt_regs *regs = ia64_task_regs(task);
+ pfm_overflow_handler(task, ctx, t->pmcs[0], regs);
}
- sema_init(&nctx->ctx_restart_sem, 0); /* reset this semaphore to locked */
-
/*
- * propagate kernel psr in new context (used for first ctxsw in
+ * we clear PMC0, to ensure that any in flight interrupt
+ * will not be attributed to the new context we are installing
+ * because the actual overflow has been processed above already.
+ * No real effect until we unmask interrupts at the end of the
+ * function.
*/
- nctx->ctx_saved_psr = pfm_get_psr();
+ pfm_unfreeze_pmu();
/*
- * propagate kernel psr in new context (used for first ctxsw in
+ * we just did a reload, so we reset the partial reload fields
*/
- nctx->ctx_saved_psr = pfm_get_psr();
+ ctx->ctx_reload_pmcs[0] = 0UL;
+ ctx->ctx_reload_pmds[0] = 0UL;
- /* link with new task */
- thread->pfm_context = nctx;
+ SET_LAST_CPU(ctx, smp_processor_id());
- DBprintk(("nctx=%p for process [%d]\n", (void *)nctx, task->pid));
+ /*
+ * dump activation value for this PMU
+ */
+ INC_ACTIVATION();
+ /*
+ * record current activation for this context
+ */
+ SET_ACTIVATION(ctx);
/*
- * the copy_thread routine automatically clears
- * IA64_THREAD_PM_VALID, so we need to reenable it, if it was used by the caller
+ * establish new ownership. Interrupts
+ * are still masked at this point.
*/
- if (current->thread.flags & IA64_THREAD_PM_VALID) {
- DBprintk(("setting PM_VALID for [%d]\n", task->pid));
- thread->flags |= IA64_THREAD_PM_VALID;
- }
+ SET_PMU_OWNER(task, ctx);
- preempt_enable();
+ /*
+ * restore the psr we changed
+ */
+ pfm_set_psr_l(psr);
- return 0;
+ /*
+ * allow concurrent access to context
+ */
+ pfm_unprotect_ctx_ctxsw(ctx, flags);
}
-
-/*
- *
- * We cannot touch any of the PMU registers at this point as we may
- * not be running on the same CPU the task was last run on. Therefore
- * it is assumed that the PMU has been stopped appropriately in
- * pfm_flush_regs() called from exit_thread().
- *
- * The function is called in the context of the parent via a release_thread()
- * and wait4(). The task is not in the tasklist anymore.
+#else /* !CONFIG_SMP */
+/*
+ * reload PMU state for UP kernels
+ * in 2.5 we come here with interrupts disabled
*/
void
-pfm_context_exit(struct task_struct *task)
+pfm_load_regs (struct task_struct *task)
{
- pfm_context_t *ctx = task->thread.pfm_context;
-
- /*
- * check sampling buffer
- */
- preempt_disable();
- if (ctx->ctx_psb) {
- pfm_smpl_buffer_desc_t *psb = ctx->ctx_psb;
-
- LOCK_PSB(psb);
-
- DBprintk(("sampling buffer from [%d] @%p size %ld refcnt=%lu psb_flags=0x%x\n",
- task->pid,
- psb->psb_hdr, psb->psb_size, psb->psb_refcnt, psb->psb_flags));
+ struct thread_struct *t;
+ pfm_context_t *ctx;
+ struct task_struct *owner;
+ unsigned long pmd_mask, pmc_mask;
+ u64 psr;
- /*
- * in the case where we are the last user, we may be able to free
- * the buffer
- */
- psb->psb_refcnt--;
+ owner = GET_PMU_OWNER();
+ ctx = PFM_GET_CTX(task);
+ t = &task->thread;
- if (psb->psb_refcnt == 0) {
+#if 1
+ psr = pfm_get_psr();
+ if (psr & IA64_PSR_UP) {
+ printk(KERN_ERR " perfmon: pfm_load_regs: psr.up set current [%d] owner [%d] psr=0x%lx\n", current->pid, owner->pid, psr);
+ }
+ psr = pfm_get_psr();
+ if (psr & IA64_PSR_I) {
+ printk(KERN_ERR " perfmon: pfm_load_regs: psr.i set current [%d] owner [%d] psr=0x%lx\n", current->pid, owner->pid, psr);
+ }
+#endif
- /*
- * The flag is cleared in pfm_vm_close(). which gets
- * called from do_exit() via exit_mm().
- * By the time we come here, the task has no more mm context.
- *
- * We can only free the psb and buffer here after the vm area
- * describing the buffer has been removed. This normally happens
- * as part of do_exit() but the entire mm context is ONLY removed
- * once its reference counts goes to zero. This is typically
- * the case except for multi-threaded (several tasks) processes.
- *
- * See pfm_vm_close() and pfm_cleanup_smpl_buf() for more details.
- */
- if ((psb->psb_flags & PSB_HAS_VMA) == 0) {
-
- DBprintk(("cleaning sampling buffer from [%d] @%p size %ld\n",
- task->pid,
- psb->psb_hdr, psb->psb_size));
-
- /*
- * free the buffer and psb
- */
- pfm_rvfree(psb->psb_hdr, psb->psb_size);
- kfree(psb);
- psb = NULL;
- }
- }
- /* psb may have been deleted */
- if (psb) UNLOCK_PSB(psb);
- }
-
- DBprintk(("cleaning [%d] pfm_context @%p notify_task=%p check=%d mm=%p\n",
- task->pid, ctx,
- ctx->ctx_notify_task,
- atomic_read(&task->thread.pfm_notifiers_check), task->mm));
-
- /*
- * To avoid getting the notified task or owner task scan the entire process
- * list when they exit, we decrement notifiers_check and owners_check respectively.
+ /*
+ * we restore ALL the debug registers to avoid picking up
+ * stale state.
*
- * Of course, there is race condition between decreasing the value and the
- * task exiting. The danger comes from the fact that, in both cases, we have a
- * direct pointer to a task structure thereby bypassing the tasklist.
- * We must make sure that, if we have task!= NULL, the target task is still
- * present and is identical to the initial task specified
- * during pfm_context_create(). It may already be detached from the tasklist but
- * that's okay. Note that it is okay if we miss the deadline and the task scans
- * the list for nothing, it will affect performance but not correctness.
- * The correctness is ensured by using the ctx_lock which prevents the
- * notify_task from changing the fields in our context.
- * Once holdhing this lock, if we see task!= NULL, then it will stay like
- * that until we release the lock. If it is NULL already then we came too late.
- */
- LOCK_CTX(ctx);
-
- if (ctx->ctx_notify_task != NULL) {
- DBprintk(("[%d], [%d] atomic_sub on [%d] notifiers=%u\n", current->pid,
- task->pid,
- ctx->ctx_notify_task->pid,
- atomic_read(&ctx->ctx_notify_task->thread.pfm_notifiers_check)));
-
- atomic_dec(&ctx->ctx_notify_task->thread.pfm_notifiers_check);
+ * This must be done even when the task is still the owner
+ * as the registers may have been modified via ptrace()
+ * (not perfmon) by the previous task.
+ */
+ if (ctx->ctx_fl_using_dbreg) {
+ pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf.num_ibrs);
+ pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf.num_dbrs);
}
- if (ctx->ctx_owner != NULL) {
- DBprintk(("[%d], [%d] atomic_sub on [%d] owners=%u\n",
- current->pid,
- task->pid,
- ctx->ctx_owner->pid,
- atomic_read(&ctx->ctx_owner->thread.pfm_owners_check)));
+ /*
+ * retrieved save psr
+ */
+ psr = ctx->ctx_saved_psr;
- atomic_dec(&ctx->ctx_owner->thread.pfm_owners_check);
+ /*
+ * short path, our state is still there, just
+ * need to restore psr and we go
+ *
+ * we do not touch either PMC nor PMD. the psr is not touched
+ * by the overflow_handler. So we are safe w.r.t. to interrupt
+ * concurrency even without interrupt masking.
+ */
+ if (likely(owner == task)) {
+ pfm_set_psr_l(psr);
+ return;
}
- UNLOCK_CTX(ctx);
- preempt_enable();
+ DPRINT(("reload for [%d] owner=%d\n", task->pid, owner ? owner->pid : -1));
- pfm_unreserve_session(task, ctx->ctx_fl_system, 1UL << ctx->ctx_cpu);
-
- if (ctx->ctx_fl_system) {
- /*
- * remove any CPU pinning
- */
- set_cpus_allowed(task, ctx->ctx_saved_cpus_allowed);
- }
+ /*
+ * someone else is still using the PMU, first push it out and
+ * then we'll be able to install our stuff !
+ *
+ * Upon return, there will be no owner for the current PMU
+ */
+ if (owner) pfm_lazy_save_regs(owner);
- pfm_context_free(ctx);
- /*
- * clean pfm state in thread structure,
+ /*
+ * To avoid leaking information to the user level when psr.sp=0,
+ * we must reload ALL implemented pmds (even the ones we don't use).
+ * In the kernel we only allow PFM_READ_PMDS on registers which
+ * we initialized or requested (sampling) so there is no risk there.
*/
- task->thread.pfm_context = NULL;
- task->thread.pfm_ovfl_block_reset = 0;
+ pmd_mask = pfm_sysctl.fastctxsw ? ctx->ctx_used_pmds[0] : ctx->ctx_all_pmds[0];
- /* pfm_notifiers is cleaned in pfm_cleanup_notifiers() */
-}
+ /*
+ * ALL accessible PMCs are systematically reloaded, unused registers
+ * get their default (from pfm_reset_pmu_state()) values to avoid picking
+ * up stale configuration.
+ *
+ * PMC0 is never in the mask. It is always restored separately
+ */
+ pmc_mask = ctx->ctx_all_pmcs[0];
-/*
- * function invoked from release_thread when pfm_smpl_buf_list is not NULL
- */
-int
-pfm_cleanup_smpl_buf(struct task_struct *task)
-{
- pfm_smpl_buffer_desc_t *tmp, *psb = task->thread.pfm_smpl_buf_list;
+ pfm_restore_pmds(t->pmds, pmd_mask);
+ pfm_restore_pmcs(t->pmcs, pmc_mask);
- if (psb == NULL) {
- printk(KERN_DEBUG "perfmon: psb is null in [%d]\n", current->pid);
- return -1;
+ /*
+ * Check for pending overflow when state was last saved.
+ * invoked handler is overflow status bits set.
+ *
+ * Any PMU overflow in flight at this point, will still
+ * be treated as spurious because we have no declared
+ * owner. Note that the first level interrupt handler
+ * DOES NOT TOUCH any PMC except PMC0 for which we have
+ * a copy already.
+ */
+ if (unlikely(PMC0_HAS_OVFL(t->pmcs[0]))) {
+ struct pt_regs *regs = ia64_task_regs(task);
+ pfm_overflow_handler(task, ctx, t->pmcs[0], regs);
}
+
/*
- * Walk through the list and free the sampling buffer and psb
+ * we clear PMC0, to ensure that any in flight interrupt
+ * will not be attributed to the new context we are installing
+ * because the actual overflow has been processed above already.
+ *
+ * This is an atomic operation.
*/
- while (psb) {
- DBprintk(("[%d] freeing smpl @%p size %ld\n", current->pid, psb->psb_hdr, psb->psb_size));
+ pfm_unfreeze_pmu();
- pfm_rvfree(psb->psb_hdr, psb->psb_size);
- tmp = psb->psb_next;
- kfree(psb);
- psb = tmp;
- }
+ /*
+ * establish new ownership. If there was an in-flight
+ * overflow interrupt, it will be treated as spurious
+ * before and after the call, because no overflow
+ * status bit can possibly be set. No new overflow
+ * can be generated because, at this point, psr.up
+ * is still cleared.
+ */
+ SET_PMU_OWNER(task, ctx);
- /* just in case */
- task->thread.pfm_smpl_buf_list = NULL;
+ /*
+ * restore the psr. This is the point at which
+ * new overflow interrupts can be generated again.
+ */
+ pfm_set_psr_l(psr);
- return 0;
}
+#endif /* CONFIG_SMP */
/*
- * function invoked from release_thread to make sure that the ctx_owner field does not
- * point to an unexisting task.
+ * this function assumes monitoring is stopped
*/
-void
-pfm_cleanup_owners(struct task_struct *task)
+static void
+pfm_flush_pmds(struct task_struct *task, pfm_context_t *ctx)
{
- struct task_struct *g, *p;
- pfm_context_t *ctx;
-
- DBprintk(("called by [%d] for [%d]\n", current->pid, task->pid));
+ u64 pmc0;
+ unsigned long mask2, val, pmd_val;
+ int i, can_access_pmu = 0;
+ int is_self;
- read_lock(&tasklist_lock);
+ /*
+ * is the caller the task being monitored (or which initiated the
+ * session for system wide measurements)
+ */
+ is_self = ctx->ctx_task == task ? 1 : 0;
- do_each_thread(g, p) {
+#ifdef CONFIG_SMP
+ if (task == current) {
+#else
+ /*
+ * in UP, the state can still be in the registers
+ */
+ if (task == current || GET_PMU_OWNER() == task) {
+#endif
+ can_access_pmu = 1;
/*
- * It is safe to do the 2-step test here, because thread.ctx
- * is cleaned up only in release_thread() and at that point
- * the task has been detached from the tasklist which is an
- * operation which uses the write_lock() on the tasklist_lock
- * so it cannot run concurrently to this loop. So we have the
- * guarantee that if we find p and it has a perfmon ctx then
- * it is going to stay like this for the entire execution of this
- * loop.
+ * Mark the PMU as not owned
+ * This will cause the interrupt handler to do nothing in case an overflow
+ * interrupt was in-flight
+ * This also guarantees that pmc0 will contain the final state
+ * It virtually gives us full control on overflow processing from that point
+ * on.
*/
- ctx = p->thread.pfm_context;
-
- //DBprintk(("[%d] scanning task [%d] ctx=%p\n", task->pid, p->pid, ctx));
-
- if (ctx && ctx->ctx_owner == task) {
- DBprintk(("trying for owner [%d] in [%d]\n", task->pid, p->pid));
- /*
- * the spinlock is required to take care of a race condition
- * with the send_sig_info() call. We must make sure that
- * either the send_sig_info() completes using a valid task,
- * or the notify_task is cleared before the send_sig_info()
- * can pick up a stale value. Note that by the time this
- * function is executed the 'task' is already detached from the
- * tasklist. The problem is that the notifiers have a direct
- * pointer to it. It is okay to send a signal to a task in this
- * stage, it simply will have no effect. But it is better than sending
- * to a completely destroyed task or worse to a new task using the same
- * task_struct address.
- */
- LOCK_CTX(ctx);
-
- ctx->ctx_owner = NULL;
-
- UNLOCK_CTX(ctx);
-
- DBprintk(("done for notifier [%d] in [%d]\n", task->pid, p->pid));
- }
- } while_each_thread(g, p);
-
- read_unlock(&tasklist_lock);
-
- atomic_set(&task->thread.pfm_owners_check, 0);
-}
+ SET_PMU_OWNER(NULL, NULL);
+ /*
+ * read current overflow status:
+ *
+ * we are guaranteed to read the final stable state
+ */
+ ia64_srlz_d();
+ pmc0 = ia64_get_pmc(0); /* slow */
-/*
- * function called from release_thread to make sure that the ctx_notify_task is not pointing
- * to an unexisting task
- */
-void
-pfm_cleanup_notifiers(struct task_struct *task)
-{
- struct task_struct *g, *p;
- pfm_context_t *ctx;
+ /*
+ * reset freeze bit, overflow status information destroyed
+ */
+ pfm_unfreeze_pmu();
+ } else {
+ pmc0 = task->thread.pmcs[0];
+ /*
+ * clear whatever overflow status bits there were
+ */
+ task->thread.pmcs[0] &= ~0x1;
+ }
- DBprintk(("called by [%d] for [%d]\n", current->pid, task->pid));
+ /*
+ * we save all the used pmds
+ * we take care of overflows for counting PMDs
+ *
+ * XXX: sampling situation is not taken into account here
+ */
+ mask2 = ctx->ctx_used_pmds[0];
+ for (i = 0; mask2; i++, mask2>>=1) {
- read_lock(&tasklist_lock);
+ /* skip non used pmds */
+ if ((mask2 & 0x1) == 0) continue;
- do_each_thread(g, p) {
/*
- * It is safe to do the 2-step test here, because thread.ctx is cleaned up
- * only in release_thread() and at that point the task has been detached
- * from the tasklist which is an operation which uses the write_lock() on
- * the tasklist_lock so it cannot run concurrently to this loop. So we
- * have the guarantee that if we find p and it has a perfmon ctx then it
- * is going to stay like this for the entire execution of this loop.
+ * can access PMU always true in system wide mode
*/
- ctx = p->thread.pfm_context;
+ val = pmd_val = can_access_pmu ? ia64_get_pmd(i) : task->thread.pmds[i];
- //DBprintk(("[%d] scanning task [%d] ctx=%p\n", task->pid, p->pid, ctx));
+ if (PMD_IS_COUNTING(i)) {
+ DPRINT(("[%d] pmd[%d] ctx_pmd=0x%lx hw_pmd=0x%lx\n",
+ task->pid,
+ i,
+ ctx->ctx_pmds[i].val,
+ val & pmu_conf.ovfl_val));
- if (ctx && ctx->ctx_notify_task == task) {
- DBprintk(("trying for notifier [%d] in [%d]\n", task->pid, p->pid));
/*
- * the spinlock is required to take care of a race condition
- * with the send_sig_info() call. We must make sure that
- * either the send_sig_info() completes using a valid task,
- * or the notify_task is cleared before the send_sig_info()
- * can pick up a stale value. Note that by the time this
- * function is executed the 'task' is already detached from the
- * tasklist. The problem is that the notifiers have a direct
- * pointer to it. It is okay to send a signal to a task in this
- * stage, it simply will have no effect. But it is better than sending
- * to a completely destroyed task or worse to a new task using the same
- * task_struct address.
+ * we rebuild the full 64 bit value of the counter
*/
- LOCK_CTX(ctx);
-
- ctx->ctx_notify_task = NULL;
+ val = ctx->ctx_pmds[i].val + (val & pmu_conf.ovfl_val);
- UNLOCK_CTX(ctx);
+ /*
+ * now everything is in ctx_pmds[] and we need
+ * to clear the saved context from save_regs() such that
+ * pfm_read_pmds() gets the correct value
+ */
+ pmd_val = 0UL;
- DBprintk(("done for notifier [%d] in [%d]\n", task->pid, p->pid));
+ /*
+ * take care of overflow inline
+ */
+ if (pmc0 & (1UL << i)) {
+ val += 1 + pmu_conf.ovfl_val;
+ DPRINT(("[%d] pmd[%d] overflowed\n", task->pid, i));
+ }
}
- } while_each_thread(g, p);
- read_unlock(&tasklist_lock);
+ DPRINT(("[%d] is_self=%d ctx_pmd[%d]=0x%lx pmd_val=0x%lx\n", task->pid, is_self, i, val, pmd_val));
- atomic_set(&task->thread.pfm_notifiers_check, 0);
+ if (is_self) task->thread.pmds[i] = pmd_val;
+ ctx->ctx_pmds[i].val = val;
+ }
}
static struct irqaction perfmon_irqaction = {
- .handler = pfm_interrupt_handler,
- .flags = SA_INTERRUPT,
- .name = "perfmon"
+ .handler = pfm_interrupt_handler,
+ .flags = SA_INTERRUPT,
+ .name = "perfmon"
};
-int
-pfm_install_alternate_syswide_subsystem(pfm_intr_handler_desc_t *hdl)
-{
- int ret;
-
-
- /* some sanity checks */
- if (hdl == NULL || hdl->handler == NULL) {
- return -EINVAL;
- }
-
- /* do the easy test first */
- if (pfm_alternate_intr_handler) {
- return -EBUSY;
- }
-
- preempt_disable();
- /* reserve our session */
- ret = pfm_reserve_session(NULL, 1, cpu_online_map);
- if (ret) {
- preempt_enable();
- return ret;
- }
-
- if (pfm_alternate_intr_handler) {
- preempt_enable();
- printk(KERN_DEBUG "perfmon: install_alternate, intr_handler not NULL "
- "after reserve\n");
- return -EINVAL;
- }
-
- pfm_alternate_intr_handler = hdl;
-
- preempt_enable();
- return 0;
-}
-
-int
-pfm_remove_alternate_syswide_subsystem(pfm_intr_handler_desc_t *hdl)
-{
- if (hdl == NULL)
- return -EINVAL;
-
- /* cannot remove someone else's handler! */
- if (pfm_alternate_intr_handler != hdl)
- return -EINVAL;
-
- preempt_disable();
- pfm_alternate_intr_handler = NULL;
-
- /*
- * XXX: assume cpu_online_map has not changed since reservation
- */
- pfm_unreserve_session(NULL, 1, cpu_online_map);
-
- preempt_enable();
-
- return 0;
-}
-
/*
* perfmon initialization routine, called from the initcall() table
*/
+static int init_pfm_fs(void);
+
int __init
pfm_init(void)
{
unsigned int n, n_counters, i;
- pmu_conf.disabled = 1;
+ printk("perfmon: version %u.%u IRQ %u\n",
+ PFM_VERSION_MAJ,
+ PFM_VERSION_MIN,
+ IA64_PERFMON_VECTOR);
- printk(KERN_INFO "perfmon: version %u.%u IRQ %u\n", PFM_VERSION_MAJ, PFM_VERSION_MIN,
- IA64_PERFMON_VECTOR);
+ /*
+ * PMU type sanity check
+ * XXX: maybe better to implement autodetection (but then we have a larger kernel)
+ */
+ if (local_cpu_data->family != pmu_conf.pmu_family) {
+ printk(KERN_INFO "perfmon: disabled, kernel only supports %s PMU family\n", pmu_conf.pmu_name);
+ return -ENODEV;
+ }
/*
* compute the number of implemented PMD/PMC from the
pmu_conf.num_pmds = n;
pmu_conf.num_counters = n_counters;
- printk(KERN_INFO "perfmon: %u PMCs, %u PMDs, %u counters (%lu bits)\n",
+ /*
+ * sanity checks on the number of debug registers
+ */
+ if (pmu_conf.use_rr_dbregs) {
+ if (pmu_conf.num_ibrs > IA64_NUM_DBG_REGS) {
+ printk(KERN_INFO "perfmon: unsupported number of code debug registers (%u)\n", pmu_conf.num_ibrs);
+ return -1;
+ }
+ if (pmu_conf.num_dbrs > IA64_NUM_DBG_REGS) {
+ printk(KERN_INFO "perfmon: unsupported number of data debug registers (%u)\n", pmu_conf.num_ibrs);
+ return -1;
+ }
+ }
+
+ printk("perfmon: %s PMU detected, %u PMCs, %u PMDs, %u counters (%lu bits)\n",
+ pmu_conf.pmu_name,
pmu_conf.num_pmcs,
pmu_conf.num_pmds,
pmu_conf.num_counters,
}
/*
- * for now here for debug purposes
+ * create /proc/perfmon (mostly for debugging purposes)
*/
perfmon_dir = create_proc_read_entry ("perfmon", 0, 0, perfmon_read_entry, NULL);
if (perfmon_dir == NULL) {
}
/*
- * create /proc/perfmon
+ * create /proc/sys/kernel/perfmon (for debugging purposes)
*/
pfm_sysctl_header = register_sysctl_table(pfm_sysctl_root, 0);
* initialize all our spinlocks
*/
spin_lock_init(&pfm_sessions.pfs_lock);
+ spin_lock_init(&pfm_smpl_fmt_lock);
+
+ init_pfm_fs();
+
+ for(i=0; i < NR_CPUS; i++) pfm_stats[i].pfm_ovfl_intr_cycles_min = ~0UL;
/* we are all set */
- pmu_conf.disabled = 0;
+ pmu_conf.enabled = 1;
return 0;
}
+
__initcall(pfm_init);
void
-pfm_init_percpu(void)
+pfm_init_percpu (void)
{
int i;
- int me = get_cpu();
- if (me == 0)
+ /*
+ * make sure no measurement is active
+ * (may inherit programmed PMCs from EFI).
+ */
+ pfm_clear_psr_pp();
+ pfm_clear_psr_up();
+
+
+ if (smp_processor_id() == 0)
register_percpu_irq(IA64_PERFMON_VECTOR, &perfmon_irqaction);
ia64_set_pmv(IA64_PERFMON_VECTOR);
*
* At this point, pmu_conf has not yet been initialized
*
- * On McKinley, this code is ineffective until PMC4 is initialized.
+ * On McKinley, this code is ineffective until PMC4 is initialized
+ * but that's all right because we take care of pmc0 later.
+ *
+ * XXX: potential problems with pmc1.
*/
for (i=1; PMC_IS_LAST(i) == 0; i++) {
if (PMC_IS_IMPL(i) == 0) continue;
ia64_set_pmc(i, PMC_DFL_VAL(i));
}
- for (i=0; PMD_IS_LAST(i); i++) {
+ for (i=0; PMD_IS_LAST(i) == 0; i++) {
if (PMD_IS_IMPL(i) == 0) continue;
ia64_set_pmd(i, 0UL);
}
- put_cpu();
- pfm_freeze_pmu();
+
+ /*
+ * we run with the PMU not frozen at all times
+ */
+ pfm_unfreeze_pmu();
+}
+
+/*
+ * used for debug purposes only
+ */
+void
+dump_pmu_state(void)
+{
+ struct task_struct *task;
+ struct thread_struct *t;
+ pfm_context_t *ctx;
+ unsigned long psr;
+ int i;
+
+ printk("current [%d] %s\n", current->pid, current->comm);
+
+ task = GET_PMU_OWNER();
+ ctx = GET_PMU_CTX();
+
+ printk("owner [%d] ctx=%p\n", task ? task->pid : -1, ctx);
+
+ psr = pfm_get_psr();
+
+ printk("psr.pp=%ld psr.up=%ld\n", (psr >> IA64_PSR_PP_BIT) &0x1UL, (psr >> IA64_PSR_PP_BIT)&0x1UL);
+
+ t = ¤t->thread;
+
+ for (i=1; PMC_IS_LAST(i) == 0; i++) {
+ if (PMC_IS_IMPL(i) == 0) continue;
+ printk("pmc[%d]=0x%lx tpmc=0x%lx\n", i, ia64_get_pmc(i), t->pmcs[i]);
+ }
+
+ for (i=1; PMD_IS_LAST(i) == 0; i++) {
+ if (PMD_IS_IMPL(i) == 0) continue;
+ printk("pmd[%d]=0x%lx tpmd=0x%lx\n", i, ia64_get_pmd(i), t->pmds[i]);
+ }
+ if (ctx) {
+ printk("ctx_state=%d vaddr=%p addr=%p fd=%d ctx_task=[%d] saved_psr=0x%lx\n",
+ ctx->ctx_state,
+ ctx->ctx_smpl_vaddr,
+ ctx->ctx_smpl_hdr,
+ ctx->ctx_msgq_head,
+ ctx->ctx_msgq_tail,
+ ctx->ctx_saved_psr);
+ }
}
-#else /* !CONFIG_PERFMON */
+/*
+ * called from process.c:copy_thread(). task is new child.
+ */
+void
+pfm_inherit(struct task_struct *task, struct pt_regs *regs)
+{
+ struct thread_struct *thread;
+
+ DPRINT(("perfmon: pfm_inherit clearing state for [%d] current [%d]\n", task->pid, current->pid));
+
+ thread = &task->thread;
+
+ /*
+ * cut links inherited from parent (current)
+ */
+ thread->pfm_context = NULL;
+
+ PFM_SET_WORK_PENDING(task, 0);
+ /*
+ * restore default psr settings
+ */
+ ia64_psr(regs)->pp = ia64_psr(regs)->up = 0;
+ ia64_psr(regs)->sp = 1;
+}
+#else /* !CONFIG_PERFMON */
asmlinkage long
-sys_perfmonctl (int pid, int cmd, void *req, int count, long arg5, long arg6,
- long arg7, long arg8, long stack)
+sys_perfmonctl (int fd, int cmd, void *arg, int count, long arg5, long arg6, long arg7,
+ long arg8, long stack)
{
return -ENOSYS;
}
-
-#endif /* !CONFIG_PERFMON */
+#endif /* CONFIG_PERFMON */
projects / linux-flexiantxendom0-3.2.10.git / blobdiff