From 430ee8819553f66fe00e36f676a45886d76e7e8b Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Thu, 1 Dec 2011 17:00:22 +0100 Subject: nohz: Remove update_ts_time_stat from tick_nohz_start_idle There is no reason to call update_ts_time_stat from tick_nohz_start_idle anymore (after e0e37c20 sched: Eliminate the ts->idle_lastupdate field) when we updated idle_lastupdate unconditionally. We haven't set idle_active yet and do not provide last_update_time so the whole call end up being just 2 wasted branches. Signed-off-by: Michal Hocko Cc: Arjan van de Ven Link: http://lkml.kernel.org/r/1322755222-6951-1-git-send-email-mhocko@suse.cz Signed-off-by: Thomas Gleixner --- kernel/time/tick-sched.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) (limited to 'kernel/time/tick-sched.c') diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 7656642..8cfffd9 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -182,11 +182,7 @@ static void tick_nohz_stop_idle(int cpu, ktime_t now) static ktime_t tick_nohz_start_idle(int cpu, struct tick_sched *ts) { - ktime_t now; - - now = ktime_get(); - - update_ts_time_stats(cpu, ts, now, NULL); + ktime_t now = ktime_get(); ts->idle_entrytime = now; ts->idle_active = 1; -- cgit v1.1 From 15f827be93928890bba965bc175caee50c4406d2 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Tue, 24 Jan 2012 18:59:43 +0100 Subject: nohz: Remove ts->Einidle checks before restarting the tick ts->inidle is set by tick_nohz_idle_enter() and unset by tick_nohz_idle_exit(). However these two calls are assumed to be always paired. This means that by the time we call tick_nohz_idle_exit(), ts->inidle is supposed to be always set to 1. Remove the checks for ts->inidle in tick_nohz_idle_exit(). This simplifies a bit the code and improves its debuggability (ie: ensure the call is paired with a tick_nohz_idle_enter() call). Signed-off-by: Frederic Weisbecker Reviewed-by: Yong Zhang Cc: Peter Zijlstra Cc: John Stultz Cc: Ingo Molnar Link: http://lkml.kernel.org/r/1327427984-23282-2-git-send-email-fweisbec@gmail.com Signed-off-by: Thomas Gleixner --- kernel/time/tick-sched.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'kernel/time/tick-sched.c') diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 8cfffd9..3526038 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -558,20 +558,21 @@ void tick_nohz_idle_exit(void) local_irq_disable(); - if (ts->idle_active || (ts->inidle && ts->tick_stopped)) + WARN_ON_ONCE(!ts->inidle); + + ts->inidle = 0; + + if (ts->idle_active || ts->tick_stopped) now = ktime_get(); if (ts->idle_active) tick_nohz_stop_idle(cpu, now); - if (!ts->inidle || !ts->tick_stopped) { - ts->inidle = 0; + if (!ts->tick_stopped) { local_irq_enable(); return; } - ts->inidle = 0; - /* Update jiffies first */ select_nohz_load_balancer(0); tick_do_update_jiffies64(now); -- cgit v1.1