#include <linux/time.h>
#include <linux/interrupt.h>
#include <linux/efi.h>
-#include <linux/profile.h>
#include <linux/timex.h>
+#include <linux/clocksource.h>
+#include <linux/platform_device.h>
#include <asm/machvec.h>
#include <asm/delay.h>
#include <asm/hw_irq.h>
+#include <asm/paravirt.h>
#include <asm/ptrace.h>
#include <asm/sal.h>
#include <asm/sections.h>
-#include <asm/system.h>
+
+#include "fsyscall_gtod_data.h"
+
+static cycle_t itc_get_cycles(struct clocksource *cs);
+
+struct fsyscall_gtod_data_t fsyscall_gtod_data;
+
+struct itc_jitter_data_t itc_jitter_data;
volatile int time_keeper_id = 0; /* smp_processor_id() of time-keeper */
#endif
-static struct time_interpolator itc_interpolator = {
- .shift = 16,
- .mask = 0xffffffffffffffffLL,
- .source = TIME_SOURCE_CPU
+#ifdef CONFIG_PARAVIRT
+/* We need to define a real function for sched_clock, to override the
+ weak default version */
+unsigned long long sched_clock(void)
+{
+ return paravirt_sched_clock();
+}
+#endif
+
+#ifdef CONFIG_PARAVIRT
+static void
+paravirt_clocksource_resume(struct clocksource *cs)
+{
+ if (pv_time_ops.clocksource_resume)
+ pv_time_ops.clocksource_resume();
+}
+#endif
+
+static struct clocksource clocksource_itc = {
+ .name = "itc",
+ .rating = 350,
+ .read = itc_get_cycles,
+ .mask = CLOCKSOURCE_MASK(64),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+#ifdef CONFIG_PARAVIRT
+ .resume = paravirt_clocksource_resume,
+#endif
};
+static struct clocksource *itc_clocksource;
+
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+
+#include <linux/kernel_stat.h>
+
+extern cputime_t cycle_to_cputime(u64 cyc);
+
+/*
+ * Called from the context switch with interrupts disabled, to charge all
+ * accumulated times to the current process, and to prepare accounting on
+ * the next process.
+ */
+void ia64_account_on_switch(struct task_struct *prev, struct task_struct *next)
+{
+ struct thread_info *pi = task_thread_info(prev);
+ struct thread_info *ni = task_thread_info(next);
+ cputime_t delta_stime, delta_utime;
+ __u64 now;
+
+ now = ia64_get_itc();
+
+ delta_stime = cycle_to_cputime(pi->ac_stime + (now - pi->ac_stamp));
+ if (idle_task(smp_processor_id()) != prev)
+ account_system_time(prev, 0, delta_stime, delta_stime);
+ else
+ account_idle_time(delta_stime);
+
+ if (pi->ac_utime) {
+ delta_utime = cycle_to_cputime(pi->ac_utime);
+ account_user_time(prev, delta_utime, delta_utime);
+ }
+
+ pi->ac_stamp = ni->ac_stamp = now;
+ ni->ac_stime = ni->ac_utime = 0;
+}
+
+/*
+ * Account time for a transition between system, hard irq or soft irq state.
+ * Note that this function is called with interrupts enabled.
+ */
+void account_system_vtime(struct task_struct *tsk)
+{
+ struct thread_info *ti = task_thread_info(tsk);
+ unsigned long flags;
+ cputime_t delta_stime;
+ __u64 now;
+
+ local_irq_save(flags);
+
+ now = ia64_get_itc();
+
+ delta_stime = cycle_to_cputime(ti->ac_stime + (now - ti->ac_stamp));
+ if (irq_count() || idle_task(smp_processor_id()) != tsk)
+ account_system_time(tsk, 0, delta_stime, delta_stime);
+ else
+ account_idle_time(delta_stime);
+ ti->ac_stime = 0;
+
+ ti->ac_stamp = now;
+
+ local_irq_restore(flags);
+}
+EXPORT_SYMBOL_GPL(account_system_vtime);
+
+/*
+ * Called from the timer interrupt handler to charge accumulated user time
+ * to the current process. Must be called with interrupts disabled.
+ */
+void account_process_tick(struct task_struct *p, int user_tick)
+{
+ struct thread_info *ti = task_thread_info(p);
+ cputime_t delta_utime;
+
+ if (ti->ac_utime) {
+ delta_utime = cycle_to_cputime(ti->ac_utime);
+ account_user_time(p, delta_utime, delta_utime);
+ ti->ac_utime = 0;
+ }
+}
+
+#endif /* CONFIG_VIRT_CPU_ACCOUNTING */
static irqreturn_t
timer_interrupt (int irq, void *dev_id)
{
unsigned long new_itm;
- if (unlikely(cpu_is_offline(smp_processor_id()))) {
+ if (cpu_is_offline(smp_processor_id())) {
return IRQ_HANDLED;
}
profile_tick(CPU_PROFILING);
+ if (paravirt_do_steal_accounting(&new_itm))
+ goto skip_process_time_accounting;
+
while (1) {
update_process_times(user_mode(get_irq_regs()));
new_itm += local_cpu_data->itm_delta;
- if (smp_processor_id() == time_keeper_id) {
- /*
- * Here we are in the timer irq handler. We have irqs locally
- * disabled, but we don't know if the timer_bh is running on
- * another CPU. We need to avoid to SMP race by acquiring the
- * xtime_lock.
- */
- write_seqlock(&xtime_lock);
- do_timer(1);
- local_cpu_data->itm_next = new_itm;
- write_sequnlock(&xtime_lock);
- } else
- local_cpu_data->itm_next = new_itm;
+ if (smp_processor_id() == time_keeper_id)
+ xtime_update(1);
+
+ local_cpu_data->itm_next = new_itm;
if (time_after(new_itm, ia64_get_itc()))
break;
local_irq_disable();
}
+skip_process_time_accounting:
+
do {
/*
* If we're too close to the next clock tick for
* comfort, we increase the safety margin by
* intentionally dropping the next tick(s). We do NOT
* update itm.next because that would force us to call
- * do_timer() which in turn would let our clock run
+ * xtime_update() which in turn would let our clock run
* too fast (with the potentially devastating effect
* of losing monotony of time).
*/
+ itc_freq/2)/itc_freq;
if (!(sal_platform_features & IA64_SAL_PLATFORM_FEATURE_ITC_DRIFT)) {
- itc_interpolator.frequency = local_cpu_data->itc_freq;
- itc_interpolator.drift = itc_drift;
#ifdef CONFIG_SMP
/* On IA64 in an SMP configuration ITCs are never accurately synchronized.
* Jitter compensation requires a cmpxchg which may limit
- * the scalibility of the syscalls for retrieving time.
+ * the scalability of the syscalls for retrieving time.
* The ITC synchronization is usually successful to within a few
* ITC ticks but this is not a sure thing. If you need to improve
* timer performance in SMP situations then boot the kernel with the
* even going backward) if the ITC offsets between the individual CPUs
* are too large.
*/
- if (!nojitter) itc_interpolator.jitter = 1;
+ if (!nojitter)
+ itc_jitter_data.itc_jitter = 1;
#endif
- register_time_interpolator(&itc_interpolator);
- }
+ } else
+ /*
+ * ITC is drifty and we have not synchronized the ITCs in smpboot.c.
+ * ITC values may fluctuate significantly between processors.
+ * Clock should not be used for hrtimers. Mark itc as only
+ * useful for boot and testing.
+ *
+ * Note that jitter compensation is off! There is no point of
+ * synchronizing ITCs since they may be large differentials
+ * that change over time.
+ *
+ * The only way to fix this would be to repeatedly sync the
+ * ITCs. Until that time we have to avoid ITC.
+ */
+ clocksource_itc.rating = 50;
+
+ paravirt_init_missing_ticks_accounting(smp_processor_id());
+
+ /* avoid softlock up message when cpu is unplug and plugged again. */
+ touch_softlockup_watchdog();
/* Setup the CPU local timer tick */
ia64_cpu_local_tick();
+
+ if (!itc_clocksource) {
+ clocksource_register_hz(&clocksource_itc,
+ local_cpu_data->itc_freq);
+ itc_clocksource = &clocksource_itc;
+ }
+}
+
+static cycle_t itc_get_cycles(struct clocksource *cs)
+{
+ unsigned long lcycle, now, ret;
+
+ if (!itc_jitter_data.itc_jitter)
+ return get_cycles();
+
+ lcycle = itc_jitter_data.itc_lastcycle;
+ now = get_cycles();
+ if (lcycle && time_after(lcycle, now))
+ return lcycle;
+
+ /*
+ * Keep track of the last timer value returned.
+ * In an SMP environment, you could lose out in contention of
+ * cmpxchg. If so, your cmpxchg returns new value which the
+ * winner of contention updated to. Use the new value instead.
+ */
+ ret = cmpxchg(&itc_jitter_data.itc_lastcycle, lcycle, now);
+ if (unlikely(ret != lcycle))
+ return ret;
+
+ return now;
}
+
static struct irqaction timer_irqaction = {
.handler = timer_interrupt,
.flags = IRQF_DISABLED | IRQF_IRQPOLL,
.name = "timer"
};
-void __devinit ia64_disable_timer(void)
+static struct platform_device rtc_efi_dev = {
+ .name = "rtc-efi",
+ .id = -1,
+};
+
+static int __init rtc_init(void)
+{
+ if (platform_device_register(&rtc_efi_dev) < 0)
+ printk(KERN_ERR "unable to register rtc device...\n");
+
+ /* not necessarily an error */
+ return 0;
+}
+module_init(rtc_init);
+
+void read_persistent_clock(struct timespec *ts)
{
- ia64_set_itv(1 << 16);
+ efi_gettimeofday(ts);
}
void __init
time_init (void)
{
register_percpu_irq(IA64_TIMER_VECTOR, &timer_irqaction);
- efi_gettimeofday(&xtime);
ia64_init_itm();
-
- /*
- * Initialize wall_to_monotonic such that adding it to xtime will yield zero, the
- * tv_nsec field must be normalized (i.e., 0 <= nsec < NSEC_PER_SEC).
- */
- set_normalized_timespec(&wall_to_monotonic, -xtime.tv_sec, -xtime.tv_nsec);
}
/*
}
EXPORT_SYMBOL(udelay);
-static unsigned long long ia64_itc_printk_clock(void)
+/* IA64 doesn't cache the timezone */
+void update_vsyscall_tz(void)
{
- if (ia64_get_kr(IA64_KR_PER_CPU_DATA))
- return sched_clock();
- return 0;
}
-static unsigned long long ia64_default_printk_clock(void)
+void update_vsyscall(struct timespec *wall, struct timespec *wtm,
+ struct clocksource *c, u32 mult)
{
- return (unsigned long long)(jiffies_64 - INITIAL_JIFFIES) *
- (1000000000/HZ);
-}
-
-unsigned long long (*ia64_printk_clock)(void) = &ia64_default_printk_clock;
+ write_seqcount_begin(&fsyscall_gtod_data.seq);
+
+ /* copy fsyscall clock data */
+ fsyscall_gtod_data.clk_mask = c->mask;
+ fsyscall_gtod_data.clk_mult = mult;
+ fsyscall_gtod_data.clk_shift = c->shift;
+ fsyscall_gtod_data.clk_fsys_mmio = c->archdata.fsys_mmio;
+ fsyscall_gtod_data.clk_cycle_last = c->cycle_last;
+
+ /* copy kernel time structures */
+ fsyscall_gtod_data.wall_time.tv_sec = wall->tv_sec;
+ fsyscall_gtod_data.wall_time.tv_nsec = wall->tv_nsec;
+ fsyscall_gtod_data.monotonic_time.tv_sec = wtm->tv_sec
+ + wall->tv_sec;
+ fsyscall_gtod_data.monotonic_time.tv_nsec = wtm->tv_nsec
+ + wall->tv_nsec;
+
+ /* normalize */
+ while (fsyscall_gtod_data.monotonic_time.tv_nsec >= NSEC_PER_SEC) {
+ fsyscall_gtod_data.monotonic_time.tv_nsec -= NSEC_PER_SEC;
+ fsyscall_gtod_data.monotonic_time.tv_sec++;
+ }
-unsigned long long printk_clock(void)
-{
- return ia64_printk_clock();
+ write_seqcount_end(&fsyscall_gtod_data.seq);
}
-void __init
-ia64_setup_printk_clock(void)
-{
- if (!(sal_platform_features & IA64_SAL_PLATFORM_FEATURE_ITC_DRIFT))
- ia64_printk_clock = ia64_itc_printk_clock;
-}
projects / linux-flexiantxendom0-3.2.10.git / blobdiff