diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2021-07-13 15:39:50 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2021-08-10 17:57:22 +0200 |
| commit | 66f7b0c8aadd2785fc29f2c71477ebc16f4e38cc (patch) | |
| tree | 9a248c6ed85efc63d1299653de76991c7f280d2a | |
| parent | e71a4153b7c256ec103e79875398553808aeffd2 (diff) | |
timerfd: Provide timerfd_resume()
Resuming timekeeping is a clock-was-set event and uses the clock-was-set
notification mechanism. This is in the way of making the clock-was-set
update for hrtimers selective so unnecessary IPIs are avoided when a CPU
base does not have timers queued which are affected by the clock setting.
Provide a seperate timerfd_resume() interface so the resume logic and the
clock-was-set mechanism can be distangled in the core code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210713135158.395287410@linutronix.de
| -rw-r--r-- | fs/timerfd.c | 16 | ||||
| -rw-r--r-- | include/linux/hrtimer.h | 2 |
2 files changed, 18 insertions, 0 deletions
diff --git a/fs/timerfd.c b/fs/timerfd.c index c5509d2448e3..e9c96a0c79f1 100644 --- a/fs/timerfd.c +++ b/fs/timerfd.c @@ -115,6 +115,22 @@ void timerfd_clock_was_set(void) rcu_read_unlock(); } +static void timerfd_resume_work(struct work_struct *work) +{ + timerfd_clock_was_set(); +} + +static DECLARE_WORK(timerfd_work, timerfd_resume_work); + +/* + * Invoked from timekeeping_resume(). Defer the actual update to work so + * timerfd_clock_was_set() runs in task context. + */ +void timerfd_resume(void) +{ + schedule_work(&timerfd_work); +} + static void __timerfd_remove_cancel(struct timerfd_ctx *ctx) { if (ctx->might_cancel) { diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h index 77295af72426..253c6e25f331 100644 --- a/include/linux/hrtimer.h +++ b/include/linux/hrtimer.h @@ -349,8 +349,10 @@ hrtimer_expires_remaining_adjusted(const struct hrtimer *timer) #ifdef CONFIG_TIMERFD extern void timerfd_clock_was_set(void); +extern void timerfd_resume(void); #else static inline void timerfd_clock_was_set(void) { } +static inline void timerfd_resume(void) { } #endif extern void hrtimers_resume(void); |