diff options
| author | Stanislaw Gruszka <sgruszka@redhat.com> | 2010-03-11 23:04:31 +0100 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2010-03-12 19:12:18 +0100 |
| commit | 15365c108ea27598e265f8c13e7051d99ca5b0b9 (patch) | |
| tree | 487cc70e96a3d6696f8f62fb7b6dbaacbc84ace5 | |
| parent | timer stats: Fix del_timer_sync() and try_to_del_timer_sync() (diff) | |
| download | linux-15365c108ea27598e265f8c13e7051d99ca5b0b9.tar.xz linux-15365c108ea27598e265f8c13e7051d99ca5b0b9.zip | |
posix-cpu-timers: Reset expire cache when no timer is running
When a process deletes cpu timer or a timer expires we do not clear
the expiration cache sig->cputimer_expires.
As a result the fastpath_timer_check() which prevents us to loop over
all threads in case no timer is active is not working and we run the
slow path needlessly on every tick.
Zero sig->cputimer_expires in stop_process_timers().
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Spencer Candland <spencer@bluehost.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| -rw-r--r-- | kernel/posix-cpu-timers.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index 438ff4523513..edec25a68e9e 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -1060,9 +1060,9 @@ static void check_thread_timers(struct task_struct *tsk, } } -static void stop_process_timers(struct task_struct *tsk) +static void stop_process_timers(struct signal_struct *sig) { - struct thread_group_cputimer *cputimer = &tsk->signal->cputimer; + struct thread_group_cputimer *cputimer = &sig->cputimer; unsigned long flags; if (!cputimer->running) @@ -1071,6 +1071,10 @@ static void stop_process_timers(struct task_struct *tsk) spin_lock_irqsave(&cputimer->lock, flags); cputimer->running = 0; spin_unlock_irqrestore(&cputimer->lock, flags); + + sig->cputime_expires.prof_exp = cputime_zero; + sig->cputime_expires.virt_exp = cputime_zero; + sig->cputime_expires.sched_exp = 0; } static u32 onecputick; @@ -1131,7 +1135,7 @@ static void check_process_timers(struct task_struct *tsk, list_empty(&timers[CPUCLOCK_VIRT]) && cputime_eq(sig->it[CPUCLOCK_VIRT].expires, cputime_zero) && list_empty(&timers[CPUCLOCK_SCHED])) { - stop_process_timers(tsk); + stop_process_timers(sig); return; } |