From 84bf1bccc60cc64376125ea2eae05e4ba12f795b Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Mon, 1 Aug 2011 01:25:38 +0200 Subject: [PATCH] nohz: Move next idle expiry time record into idle logic area The next idle expiry time record and idle sleeps tracking are statistics that only concern idle. Since we want the nohz APIs to become usable further idle context, let's pull up the handling of these statistics to the callers in idle. Signed-off-by: Frederic Weisbecker Cc: Alessio Igor Bogani Cc: Andrew Morton Cc: Avi Kivity Cc: Chris Metcalf Cc: Christoph Lameter Cc: Daniel Lezcano Cc: Geoff Levand Cc: Gilad Ben Yossef Cc: Hakan Akkan Cc: Ingo Molnar Cc: Kevin Hilman Cc: Max Krasnyansky Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Stephen Hemminger Cc: Steven Rostedt Cc: Sven-Thorsten Dietrich Cc: Thomas Gleixner --- kernel/time/tick-sched.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 430e1b6901c..60c9c60e910 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -271,11 +271,11 @@ u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time) } EXPORT_SYMBOL_GPL(get_cpu_iowait_time_us); -static void tick_nohz_stop_sched_tick(struct tick_sched *ts, - ktime_t now, int cpu) +static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts, + ktime_t now, int cpu) { unsigned long seq, last_jiffies, next_jiffies, delta_jiffies; - ktime_t last_update, expires; + ktime_t last_update, expires, ret = { .tv64 = 0 }; struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev; u64 time_delta; @@ -358,6 +358,8 @@ static void tick_nohz_stop_sched_tick(struct tick_sched *ts, if (ts->tick_stopped && ktime_equal(expires, dev->next_event)) goto out; + ret = expires; + /* * nohz_stop_sched_tick can be called several times before * the nohz_restart_sched_tick is called. This happens when @@ -372,11 +374,6 @@ static void tick_nohz_stop_sched_tick(struct tick_sched *ts, ts->tick_stopped = 1; } - ts->idle_sleeps++; - - /* Mark expires */ - ts->idle_expires = expires; - /* * If the expiration time == KTIME_MAX, then * in this case we simply stop the tick timer. @@ -407,6 +404,8 @@ out: ts->next_jiffies = next_jiffies; ts->last_jiffies = last_jiffies; ts->sleep_length = ktime_sub(dev->next_event, now); + + return ret; } static bool can_stop_idle_tick(int cpu, struct tick_sched *ts) @@ -445,7 +444,7 @@ static bool can_stop_idle_tick(int cpu, struct tick_sched *ts) static void __tick_nohz_idle_enter(struct tick_sched *ts) { - ktime_t now; + ktime_t now, expires; int cpu = smp_processor_id(); now = tick_nohz_start_idle(cpu, ts); @@ -454,7 +453,12 @@ static void __tick_nohz_idle_enter(struct tick_sched *ts) int was_stopped = ts->tick_stopped; ts->idle_calls++; - tick_nohz_stop_sched_tick(ts, now, cpu); + + expires = tick_nohz_stop_sched_tick(ts, now, cpu); + if (expires.tv64 > 0LL) { + ts->idle_sleeps++; + ts->idle_expires = expires; + } if (!was_stopped && ts->tick_stopped) ts->idle_jiffies = ts->last_jiffies; -- 2.20.1