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| author | Mike Galbraith <efault@gmx.de> | 2011-04-29 08:36:50 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2011-05-16 11:01:17 +0200 |
| commit | 61eadef6a9bde9ea62fda724a9cb501ce9bc925a (patch) | |
| tree | 52ffdd4251e921681f086ec6c4e14ad6e5f9472d /kernel/sched.c | |
| parent | 3e51e3edfd81bfd9853ad7de91167e4ce33d0fe7 (diff) | |
| download | lwn-61eadef6a9bde9ea62fda724a9cb501ce9bc925a.tar.gz lwn-61eadef6a9bde9ea62fda724a9cb501ce9bc925a.zip | |
sched, rt: Update rq clock when unthrottling of an otherwise idle CPU
If an RT task is awakened while it's rt_rq is throttled, the time between
wakeup/enqueue and unthrottle/selection may be accounted as rt_time
if the CPU is idle. Set rq->skip_clock_update negative upon throttle
release to tell put_prev_task() that we need a clock update.
Reported-by: Thomas Giesel <skoe@directbox.com>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1304059010.7472.1.camel@marge.simson.net
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/sched.c')
| -rw-r--r-- | kernel/sched.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index f9778c0d91e2..b8b9a7dac9b0 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -466,7 +466,7 @@ struct rq { u64 nohz_stamp; unsigned char nohz_balance_kick; #endif - unsigned int skip_clock_update; + int skip_clock_update; /* capture load from *all* tasks on this cpu: */ struct load_weight load; @@ -652,7 +652,7 @@ static void update_rq_clock(struct rq *rq) { s64 delta; - if (rq->skip_clock_update) + if (rq->skip_clock_update > 0) return; delta = sched_clock_cpu(cpu_of(rq)) - rq->clock; @@ -4127,7 +4127,7 @@ static inline void schedule_debug(struct task_struct *prev) static void put_prev_task(struct rq *rq, struct task_struct *prev) { - if (prev->on_rq) + if (prev->on_rq || rq->skip_clock_update < 0) update_rq_clock(rq); prev->sched_class->put_prev_task(rq, prev); } |