* Dynticks per-CPU state.
*/
struct rcu_dynticks {
- int dynticks_nesting; /* Track nesting level, sort of. */
- int dynticks; /* Even value for dynticks-idle, else odd. */
- int dynticks_nmi; /* Even value for either dynticks-idle or */
- /* not in nmi handler, else odd. So this */
- /* remains even for nmi from irq handler. */
+ long long dynticks_nesting; /* Track irq/process nesting level. */
+ /* Process level is worth LLONG_MAX/2. */
+ int dynticks_nmi_nesting; /* Track NMI nesting level. */
+ atomic_t dynticks; /* Even value for idle, else odd. */
};
+/* RCU's kthread states for tracing. */
+#define RCU_KTHREAD_STOPPED 0
+#define RCU_KTHREAD_RUNNING 1
+#define RCU_KTHREAD_WAITING 2
+#define RCU_KTHREAD_OFFCPU 3
+#define RCU_KTHREAD_YIELDING 4
+#define RCU_KTHREAD_MAX 4
+
/*
* Definition for node within the RCU grace-period-detection hierarchy.
*/
/* an rcu_data structure, otherwise, each */
/* bit corresponds to a child rcu_node */
/* structure. */
- unsigned long expmask; /* Groups that have ->blocked_tasks[] */
+ unsigned long expmask; /* Groups that have ->blkd_tasks */
/* elements that need to drain to allow the */
/* current expedited grace period to */
/* complete (only for TREE_PREEMPT_RCU). */
+ atomic_t wakemask; /* CPUs whose kthread needs to be awakened. */
+ /* Since this has meaning only for leaf */
+ /* rcu_node structures, 32 bits suffices. */
unsigned long qsmaskinit;
/* Per-GP initial value for qsmask & expmask. */
unsigned long grpmask; /* Mask to apply to parent qsmask. */
u8 grpnum; /* CPU/group number for next level up. */
u8 level; /* root is at level 0. */
struct rcu_node *parent;
- struct list_head blocked_tasks[4];
- /* Tasks blocked in RCU read-side critsect. */
- /* Grace period number (->gpnum) x blocked */
- /* by tasks on the (x & 0x1) element of the */
- /* blocked_tasks[] array. */
+ struct list_head blkd_tasks;
+ /* Tasks blocked in RCU read-side critical */
+ /* section. Tasks are placed at the head */
+ /* of this list and age towards the tail. */
+ struct list_head *gp_tasks;
+ /* Pointer to the first task blocking the */
+ /* current grace period, or NULL if there */
+ /* is no such task. */
+ struct list_head *exp_tasks;
+ /* Pointer to the first task blocking the */
+ /* current expedited grace period, or NULL */
+ /* if there is no such task. If there */
+ /* is no current expedited grace period, */
+ /* then there can cannot be any such task. */
+#ifdef CONFIG_RCU_BOOST
+ struct list_head *boost_tasks;
+ /* Pointer to first task that needs to be */
+ /* priority boosted, or NULL if no priority */
+ /* boosting is needed for this rcu_node */
+ /* structure. If there are no tasks */
+ /* queued on this rcu_node structure that */
+ /* are blocking the current grace period, */
+ /* there can be no such task. */
+ unsigned long boost_time;
+ /* When to start boosting (jiffies). */
+ struct task_struct *boost_kthread_task;
+ /* kthread that takes care of priority */
+ /* boosting for this rcu_node structure. */
+ unsigned int boost_kthread_status;
+ /* State of boost_kthread_task for tracing. */
+ unsigned long n_tasks_boosted;
+ /* Total number of tasks boosted. */
+ unsigned long n_exp_boosts;
+ /* Number of tasks boosted for expedited GP. */
+ unsigned long n_normal_boosts;
+ /* Number of tasks boosted for normal GP. */
+ unsigned long n_balk_blkd_tasks;
+ /* Refused to boost: no blocked tasks. */
+ unsigned long n_balk_exp_gp_tasks;
+ /* Refused to boost: nothing blocking GP. */
+ unsigned long n_balk_boost_tasks;
+ /* Refused to boost: already boosting. */
+ unsigned long n_balk_notblocked;
+ /* Refused to boost: RCU RS CS still running. */
+ unsigned long n_balk_notyet;
+ /* Refused to boost: not yet time. */
+ unsigned long n_balk_nos;
+ /* Refused to boost: not sure why, though. */
+ /* This can happen due to race conditions. */
+#endif /* #ifdef CONFIG_RCU_BOOST */
+ struct task_struct *node_kthread_task;
+ /* kthread that takes care of this rcu_node */
+ /* structure, for example, awakening the */
+ /* per-CPU kthreads as needed. */
+ unsigned int node_kthread_status;
+ /* State of node_kthread_task for tracing. */
} ____cacheline_internodealigned_in_smp;
/*
/* in order to detect GP end. */
unsigned long gpnum; /* Highest gp number that this CPU */
/* is aware of having started. */
- unsigned long passed_quiesc_completed;
- /* Value of completed at time of qs. */
- bool passed_quiesc; /* User-mode/idle loop etc. */
+ unsigned long passed_quiesce_gpnum;
+ /* gpnum at time of quiescent state. */
+ bool passed_quiesce; /* User-mode/idle loop etc. */
bool qs_pending; /* Core waits for quiesc state. */
bool beenonline; /* CPU online at least once. */
- bool preemptable; /* Preemptable RCU? */
+ bool preemptible; /* Preemptible RCU? */
struct rcu_node *mynode; /* This CPU's leaf of hierarchy */
unsigned long grpmask; /* Mask to apply to leaf qsmask. */
+#ifdef CONFIG_RCU_CPU_STALL_INFO
+ unsigned long ticks_this_gp; /* The number of scheduling-clock */
+ /* ticks this CPU has handled */
+ /* during and after the last grace */
+ /* period it is aware of. */
+#endif /* #ifdef CONFIG_RCU_CPU_STALL_INFO */
/* 2) batch handling */
/*
*/
struct rcu_head *nxtlist;
struct rcu_head **nxttail[RCU_NEXT_SIZE];
- long qlen; /* # of queued callbacks */
+ long qlen_lazy; /* # of lazy queued callbacks */
+ long qlen; /* # of queued callbacks, incl lazy */
long qlen_last_fqs_check;
/* qlen at last check for QS forcing */
unsigned long n_cbs_invoked; /* count of RCU cbs invoked. */
/* did other CPU force QS recently? */
long blimit; /* Upper limit on a processed batch */
-#ifdef CONFIG_NO_HZ
/* 3) dynticks interface. */
struct rcu_dynticks *dynticks; /* Shared per-CPU dynticks state. */
int dynticks_snap; /* Per-GP tracking for dynticks. */
- int dynticks_nmi_snap; /* Per-GP tracking for dynticks_nmi. */
-#endif /* #ifdef CONFIG_NO_HZ */
/* 4) reasons this CPU needed to be kicked by force_quiescent_state */
-#ifdef CONFIG_NO_HZ
unsigned long dynticks_fqs; /* Kicked due to dynticks idle. */
-#endif /* #ifdef CONFIG_NO_HZ */
unsigned long offline_fqs; /* Kicked due to being offline. */
- unsigned long resched_ipi; /* Sent a resched IPI. */
/* 5) __rcu_pending() statistics. */
unsigned long n_rcu_pending; /* rcu_pending() calls since boot. */
unsigned long n_rp_need_nothing;
int cpu;
+ struct rcu_state *rsp;
};
-/* Values for signaled field in struct rcu_state. */
+/* Values for fqs_state field in struct rcu_state. */
#define RCU_GP_IDLE 0 /* No grace period in progress. */
#define RCU_GP_INIT 1 /* Grace period being initialized. */
#define RCU_SAVE_DYNTICK 2 /* Need to scan dyntick state. */
#define RCU_FORCE_QS 3 /* Need to force quiescent state. */
-#ifdef CONFIG_NO_HZ
#define RCU_SIGNAL_INIT RCU_SAVE_DYNTICK
-#else /* #ifdef CONFIG_NO_HZ */
-#define RCU_SIGNAL_INIT RCU_FORCE_QS
-#endif /* #else #ifdef CONFIG_NO_HZ */
#define RCU_JIFFIES_TILL_FORCE_QS 3 /* for rsp->jiffies_force_qs */
-#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
#ifdef CONFIG_PROVE_RCU
#define RCU_STALL_DELAY_DELTA (5 * HZ)
#else
#define RCU_STALL_DELAY_DELTA 0
#endif
-
-#define RCU_SECONDS_TILL_STALL_CHECK (CONFIG_RCU_CPU_STALL_TIMEOUT * HZ + \
- RCU_STALL_DELAY_DELTA)
- /* for rsp->jiffies_stall */
-#define RCU_SECONDS_TILL_STALL_RECHECK (3 * RCU_SECONDS_TILL_STALL_CHECK + 30)
- /* for rsp->jiffies_stall */
#define RCU_STALL_RAT_DELAY 2 /* Allow other CPUs time */
/* to take at least one */
/* scheduling clock irq */
/* before ratting on them. */
-#ifdef CONFIG_RCU_CPU_STALL_DETECTOR_RUNNABLE
-#define RCU_CPU_STALL_SUPPRESS_INIT 0
-#else
-#define RCU_CPU_STALL_SUPPRESS_INIT 1
-#endif
-
-#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
+#define rcu_wait(cond) \
+do { \
+ for (;;) { \
+ set_current_state(TASK_INTERRUPTIBLE); \
+ if (cond) \
+ break; \
+ schedule(); \
+ } \
+ __set_current_state(TASK_RUNNING); \
+} while (0)
/*
* RCU global state, including node hierarchy. This hierarchy is
/* The following fields are guarded by the root rcu_node's lock. */
- u8 signaled ____cacheline_internodealigned_in_smp;
+ u8 fqs_state ____cacheline_internodealigned_in_smp;
/* Force QS state. */
u8 fqs_active; /* force_quiescent_state() */
/* is running. */
/* period because */
/* force_quiescent_state() */
/* was running. */
+ u8 boost; /* Subject to priority boost. */
unsigned long gpnum; /* Current gp number. */
unsigned long completed; /* # of last completed gp. */
/* due to lock unavailable. */
unsigned long n_force_qs_ngp; /* Number of calls leaving */
/* due to no GP active. */
-#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
unsigned long gp_start; /* Time at which GP started, */
/* but in jiffies. */
unsigned long jiffies_stall; /* Time at which to check */
/* for CPU stalls. */
-#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
+ unsigned long gp_max; /* Maximum GP duration in */
+ /* jiffies. */
char *name; /* Name of structure. */
};
DECLARE_PER_CPU(struct rcu_data, rcu_preempt_data);
#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
+#ifdef CONFIG_RCU_BOOST
+DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
+DECLARE_PER_CPU(int, rcu_cpu_kthread_cpu);
+DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
+DECLARE_PER_CPU(char, rcu_cpu_has_work);
+#endif /* #ifdef CONFIG_RCU_BOOST */
+
#ifndef RCU_TREE_NONCORE
/* Forward declarations for rcutree_plugin.h */
static void rcu_bootup_announce(void);
long rcu_batches_completed(void);
static void rcu_preempt_note_context_switch(int cpu);
-static int rcu_preempted_readers(struct rcu_node *rnp);
+static int rcu_preempt_blocked_readers_cgp(struct rcu_node *rnp);
#ifdef CONFIG_HOTPLUG_CPU
static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp,
unsigned long flags);
+static void rcu_stop_cpu_kthread(int cpu);
#endif /* #ifdef CONFIG_HOTPLUG_CPU */
-#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
static void rcu_print_detail_task_stall(struct rcu_state *rsp);
-static void rcu_print_task_stall(struct rcu_node *rnp);
+static int rcu_print_task_stall(struct rcu_node *rnp);
static void rcu_preempt_stall_reset(void);
-#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp);
#ifdef CONFIG_HOTPLUG_CPU
static int rcu_preempt_offline_tasks(struct rcu_state *rsp,
struct rcu_node *rnp,
struct rcu_data *rdp);
-static void rcu_preempt_offline_cpu(int cpu);
#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+static void rcu_preempt_cleanup_dead_cpu(int cpu);
static void rcu_preempt_check_callbacks(int cpu);
static void rcu_preempt_process_callbacks(void);
void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu));
#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_TREE_PREEMPT_RCU)
-static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp);
+static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp,
+ bool wake);
#endif /* #if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_TREE_PREEMPT_RCU) */
static int rcu_preempt_pending(int cpu);
-static int rcu_preempt_needs_cpu(int cpu);
+static int rcu_preempt_cpu_has_callbacks(int cpu);
static void __cpuinit rcu_preempt_init_percpu_data(int cpu);
-static void rcu_preempt_send_cbs_to_online(void);
+static void rcu_preempt_cleanup_dying_cpu(void);
static void __init __rcu_init_preempt(void);
-static void rcu_needs_cpu_flush(void);
+static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags);
+static void rcu_preempt_boost_start_gp(struct rcu_node *rnp);
+static void invoke_rcu_callbacks_kthread(void);
+static bool rcu_is_callbacks_kthread(void);
+#ifdef CONFIG_RCU_BOOST
+static void rcu_preempt_do_callbacks(void);
+static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp,
+ cpumask_var_t cm);
+static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
+ struct rcu_node *rnp,
+ int rnp_index);
+static void invoke_rcu_node_kthread(struct rcu_node *rnp);
+static void rcu_yield(void (*f)(unsigned long), unsigned long arg);
+#endif /* #ifdef CONFIG_RCU_BOOST */
+static void rcu_cpu_kthread_setrt(int cpu, int to_rt);
+static void __cpuinit rcu_prepare_kthreads(int cpu);
+static void rcu_prepare_for_idle_init(int cpu);
+static void rcu_cleanup_after_idle(int cpu);
+static void rcu_prepare_for_idle(int cpu);
+static void print_cpu_stall_info_begin(void);
+static void print_cpu_stall_info(struct rcu_state *rsp, int cpu);
+static void print_cpu_stall_info_end(void);
+static void zero_cpu_stall_ticks(struct rcu_data *rdp);
+static void increment_cpu_stall_ticks(void);
#endif /* #ifndef RCU_TREE_NONCORE */
projects / linux-flexiantxendom0-3.2.10.git / blobdiff