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| author | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2015-05-10 01:23:35 +0200 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2015-05-15 00:26:06 +0200 |
| commit | 75e0678e7095c486a1b39ea560f8eb51a2714d6d (patch) | |
| tree | 6bd6e984c893388fe2dae27c9f7ae2fffc4a2e42 /kernel | |
| parent | PM / sleep: Fix symbol name in a comment in kernel/power/main.c (diff) | |
| download | linux-75e0678e7095c486a1b39ea560f8eb51a2714d6d.tar.xz linux-75e0678e7095c486a1b39ea560f8eb51a2714d6d.zip | |
PM / tick: Add tracepoints for suspend-to-idle diagnostics
Add suspend/resume tracepoints to tick_freeze() and tick_unfreeze()
to catch when timekeeping is suspended and resumed during suspend-to-idle
so as to be able to check whether or not we enter the "frozen" state
and to measure the time spent in it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/time/tick-common.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index 3ae6afa1eb98..80c043052487 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -19,6 +19,7 @@ #include <linux/profile.h> #include <linux/sched.h> #include <linux/module.h> +#include <trace/events/power.h> #include <asm/irq_regs.h> @@ -457,10 +458,13 @@ void tick_freeze(void) raw_spin_lock(&tick_freeze_lock); tick_freeze_depth++; - if (tick_freeze_depth == num_online_cpus()) + if (tick_freeze_depth == num_online_cpus()) { + trace_suspend_resume(TPS("timekeeping_freeze"), + smp_processor_id(), true); timekeeping_suspend(); - else + } else { tick_suspend_local(); + } raw_spin_unlock(&tick_freeze_lock); } @@ -478,10 +482,13 @@ void tick_unfreeze(void) { raw_spin_lock(&tick_freeze_lock); - if (tick_freeze_depth == num_online_cpus()) + if (tick_freeze_depth == num_online_cpus()) { timekeeping_resume(); - else + trace_suspend_resume(TPS("timekeeping_freeze"), + smp_processor_id(), false); + } else { tick_resume_local(); + } tick_freeze_depth--; |