diff options
| author | Byungchul Park <byungchul.park@lge.com> | 2015-11-10 03:36:02 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-11-23 11:37:53 +0300 |
| commit | 525705d15e63b7455977408e4601e76e6bc41524 (patch) | |
| tree | 9e201e3afd08f1874f79c6c00b227fc360e7844a /kernel | |
| parent | 59543275488d18d878cd2ab2b1072efc1e9ac1c4 (diff) | |
| download | linux-525705d15e63b7455977408e4601e76e6bc41524.tar.xz | |
sched/fair: Consider missed ticks in NOHZ_FULL in update_cpu_load_nohz()
Usually the tick can be stopped for an idle CPU in NOHZ. However in NOHZ_FULL
mode, a non-idle CPU's tick can also be stopped. However, update_cpu_load_nohz()
does not consider the case a non-idle CPU's tick has been stopped at all.
This patch makes the update_cpu_load_nohz() know if the calling path comes
from NOHZ_FULL or idle NOHZ.
Signed-off-by: Byungchul Park <byungchul.park@lge.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1447115762-19734-3-git-send-email-byungchul.park@lge.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched/fair.c | 10 | ||||
| -rw-r--r-- | kernel/time/tick-sched.c | 8 |
2 files changed, 10 insertions, 8 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 404006ae1ac9..309b1d551f25 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4397,10 +4397,11 @@ static void update_idle_cpu_load(struct rq *this_rq) /* * Called from tick_nohz_idle_exit() -- try and fix up the ticks we missed. */ -void update_cpu_load_nohz(void) +void update_cpu_load_nohz(int active) { struct rq *this_rq = this_rq(); unsigned long curr_jiffies = READ_ONCE(jiffies); + unsigned long load = active ? weighted_cpuload(cpu_of(this_rq)) : 0; unsigned long pending_updates; if (curr_jiffies == this_rq->last_load_update_tick) @@ -4411,10 +4412,11 @@ void update_cpu_load_nohz(void) if (pending_updates) { this_rq->last_load_update_tick = curr_jiffies; /* - * We were idle, this means load 0, the current load might be - * !0 due to remote wakeups and the sort. + * In the regular NOHZ case, we were idle, this means load 0. + * In the NOHZ_FULL case, we were non-idle, we should consider + * its weighted load. */ - __update_cpu_load(this_rq, 0, pending_updates, 0); + __update_cpu_load(this_rq, load, pending_updates, active); } raw_spin_unlock(&this_rq->lock); } diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 7c7ec4515983..515edf3eb62b 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -694,11 +694,11 @@ out: return tick; } -static void tick_nohz_restart_sched_tick(struct tick_sched *ts, ktime_t now) +static void tick_nohz_restart_sched_tick(struct tick_sched *ts, ktime_t now, int active) { /* Update jiffies first */ tick_do_update_jiffies64(now); - update_cpu_load_nohz(); + update_cpu_load_nohz(active); calc_load_exit_idle(); touch_softlockup_watchdog(); @@ -725,7 +725,7 @@ static void tick_nohz_full_update_tick(struct tick_sched *ts) if (can_stop_full_tick()) tick_nohz_stop_sched_tick(ts, ktime_get(), cpu); else if (ts->tick_stopped) - tick_nohz_restart_sched_tick(ts, ktime_get()); + tick_nohz_restart_sched_tick(ts, ktime_get(), 1); #endif } @@ -916,7 +916,7 @@ void tick_nohz_idle_exit(void) tick_nohz_stop_idle(ts, now); if (ts->tick_stopped) { - tick_nohz_restart_sched_tick(ts, now); + tick_nohz_restart_sched_tick(ts, now, 0); tick_nohz_account_idle_ticks(ts); } |