diff options
| author | Chintan Pandya <cpandya@codeaurora.org> | 2014-07-31 09:38:07 +1000 |
|---|---|---|
| committer | Stephen Rothwell <sfr@canb.auug.org.au> | 2014-08-13 13:08:47 +1000 |
| commit | f8faeb1dda215e608d5c0b087df506c6b431d83a (patch) | |
| tree | 277b73e6a896499e96b66308c7b67a77862cf664 | |
| parent | cc6fe6585d894d93bd9b7ee051a59c8aebc94bee (diff) | |
timer: provide an api for deferrable timeout
schedule_timeout wakes up the CPU from IDLE state. For some use cases it
is not desirable, hence introduce a convenient API
(schedule_timeout_deferrable_interruptible) on similar pattern which uses
a deferrable timer.
Signed-off-by: Chintan Pandya <cpandya@codeaurora.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | include/linux/sched.h | 2 | ||||
| -rw-r--r-- | kernel/time/timer.c | 27 |
2 files changed, 26 insertions, 3 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h index 5c2c885ee52b..13fe36110a1e 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -376,6 +376,8 @@ extern int in_sched_functions(unsigned long addr); #define MAX_SCHEDULE_TIMEOUT LONG_MAX extern signed long schedule_timeout(signed long timeout); extern signed long schedule_timeout_interruptible(signed long timeout); +extern signed long +schedule_timeout_deferrable_interruptible(signed long timeout); extern signed long schedule_timeout_killable(signed long timeout); extern signed long schedule_timeout_uninterruptible(signed long timeout); asmlinkage void schedule(void); diff --git a/kernel/time/timer.c b/kernel/time/timer.c index aca5dfe2fa3d..e81a30181e41 100644 --- a/kernel/time/timer.c +++ b/kernel/time/timer.c @@ -1432,7 +1432,7 @@ static void process_timeout(unsigned long __data) } /** - * schedule_timeout - sleep until timeout + * __schedule_timeout - sleep until timeout * @timeout: timeout value in jiffies * * Make the current task sleep until @timeout jiffies have @@ -1457,7 +1457,8 @@ static void process_timeout(unsigned long __data) * * In all cases the return value is guaranteed to be non-negative. */ -signed long __sched schedule_timeout(signed long timeout) +static signed long +__sched __schedule_timeout(signed long timeout, unsigned long flag) { struct timer_list timer; unsigned long expire; @@ -1493,7 +1494,13 @@ signed long __sched schedule_timeout(signed long timeout) expire = timeout + jiffies; - setup_timer_on_stack(&timer, process_timeout, (unsigned long)current); + if (flag & TIMER_DEFERRABLE) + setup_deferrable_timer_on_stack(&timer, process_timeout, + (unsigned long)current); + else + setup_timer_on_stack(&timer, process_timeout, + (unsigned long)current); + __mod_timer(&timer, expire, false, TIMER_NOT_PINNED); schedule(); del_singleshot_timer_sync(&timer); @@ -1506,12 +1513,26 @@ signed long __sched schedule_timeout(signed long timeout) out: return timeout < 0 ? 0 : timeout; } + +signed long __sched schedule_timeout(signed long timeout) +{ + return __schedule_timeout(timeout, 0); +} EXPORT_SYMBOL(schedule_timeout); /* * We can use __set_current_state() here because schedule_timeout() calls * schedule() unconditionally. */ + +signed long +__sched schedule_timeout_deferrable_interruptible(signed long timeout) +{ + __set_current_state(TASK_INTERRUPTIBLE); + return __schedule_timeout(timeout, TIMER_DEFERRABLE); +} +EXPORT_SYMBOL(schedule_timeout_deferrable_interruptible); + signed long __sched schedule_timeout_interruptible(signed long timeout) { __set_current_state(TASK_INTERRUPTIBLE); |