Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
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+16
fs/timerfd.c
+16
fs/timerfd.c
···
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rcu_read_unlock();
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}
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static void timerfd_resume_work(struct work_struct *work)
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{
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timerfd_clock_was_set();
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}
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static DECLARE_WORK(timerfd_work, timerfd_resume_work);
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/*
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* Invoked from timekeeping_resume(). Defer the actual update to work so
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* timerfd_clock_was_set() runs in task context.
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*/
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void timerfd_resume(void)
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{
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schedule_work(&timerfd_work);
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}
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static void __timerfd_remove_cancel(struct timerfd_ctx *ctx)
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{
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if (ctx->might_cancel) {
+2
include/linux/hrtimer.h
+2
include/linux/hrtimer.h
···
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#ifdef CONFIG_TIMERFD
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extern void timerfd_clock_was_set(void);
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extern void timerfd_resume(void);
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#else
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static inline void timerfd_clock_was_set(void) { }
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static inline void timerfd_resume(void) { }
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#endif
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extern void hrtimers_resume(void);
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