From eae1c4ae275fe3e024454c012a548ee0d700f54c Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 30 May 2017 23:15:53 +0200 Subject: [PATCH] posix-timers: Make use of cancel/arm callbacks Replace the hrtimer calls by calls to the new try_to_cancel()/arm() kclock callbacks and move the hrtimer specific implementation into the corresponding callback functions. Signed-off-by: Thomas Gleixner Cc: Peter Zijlstra Cc: John Stultz Link: http://lkml.kernel.org/r/20170530211657.355396667@linutronix.de --- kernel/time/posix-timers.c | 181 ++++++++++++++++++++----------------- 1 file changed, 100 insertions(+), 81 deletions(-) diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c index 0332f7a60fd6..8acc9ee2c2d6 100644 --- a/kernel/time/posix-timers.c +++ b/kernel/time/posix-timers.c @@ -744,25 +744,49 @@ SYSCALL_DEFINE1(timer_getoverrun, timer_t, timer_id) return overrun; } +static void common_hrtimer_arm(struct k_itimer *timr, ktime_t expires, + bool absolute, bool sigev_none) +{ + struct hrtimer *timer = &timr->it.real.timer; + enum hrtimer_mode mode; + + mode = absolute ? HRTIMER_MODE_ABS : HRTIMER_MODE_REL; + hrtimer_init(&timr->it.real.timer, timr->it_clock, mode); + timr->it.real.timer.function = posix_timer_fn; + + if (!absolute) + expires = ktime_add_safe(expires, timer->base->get_time()); + hrtimer_set_expires(timer, expires); + + if (!sigev_none) + hrtimer_start_expires(timer, HRTIMER_MODE_ABS); +} + +static int common_hrtimer_try_to_cancel(struct k_itimer *timr) +{ + return hrtimer_try_to_cancel(&timr->it.real.timer); +} + /* Set a POSIX.1b interval timer. */ -/* timr->it_lock is taken. */ static int common_timer_set(struct k_itimer *timr, int flags, - struct itimerspec64 *new_setting, struct itimerspec64 *old_setting) + struct itimerspec64 *new_setting, + struct itimerspec64 *old_setting) { - struct hrtimer *timer = &timr->it.real.timer; - enum hrtimer_mode mode; + const struct k_clock *kc = timr->kclock; + bool sigev_none; + ktime_t expires; if (old_setting) common_timer_get(timr, old_setting); - /* disable the timer */ + /* Prevent rearming by clearing the interval */ timr->it_interval = 0; /* - * careful here. If smp we could be in the "fire" routine which will - * be spinning as we hold the lock. But this is ONLY an SMP issue. + * Careful here. On SMP systems the timer expiry function could be + * active and spinning on timr->it_lock. */ - if (hrtimer_try_to_cancel(timer) < 0) + if (kc->timer_try_to_cancel(timr) < 0) return TIMER_RETRY; timr->it_active = 0; @@ -770,30 +794,16 @@ common_timer_set(struct k_itimer *timr, int flags, ~REQUEUE_PENDING; timr->it_overrun_last = 0; - /* switch off the timer when it_value is zero */ + /* Switch off the timer when it_value is zero */ if (!new_setting->it_value.tv_sec && !new_setting->it_value.tv_nsec) return 0; - mode = flags & TIMER_ABSTIME ? HRTIMER_MODE_ABS : HRTIMER_MODE_REL; - hrtimer_init(&timr->it.real.timer, timr->it_clock, mode); - timr->it.real.timer.function = posix_timer_fn; - - hrtimer_set_expires(timer, timespec64_to_ktime(new_setting->it_value)); - - /* Convert interval */ timr->it_interval = timespec64_to_ktime(new_setting->it_interval); + expires = timespec64_to_ktime(new_setting->it_value); + sigev_none = (timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE; - /* SIGEV_NONE timers are not queued ! See common_timer_get */ - if (((timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE)) { - /* Setup correct expiry time for relative timers */ - if (mode == HRTIMER_MODE_REL) { - hrtimer_add_expires(timer, timer->base->get_time()); - } - return 0; - } - - timr->it_active = 1; - hrtimer_start_expires(timer, mode); + kc->timer_arm(timr, expires, flags & TIMER_ABSTIME, sigev_none); + timr->it_active = !sigev_none; return 0; } @@ -847,9 +857,10 @@ retry: static int common_timer_del(struct k_itimer *timer) { - timer->it_interval = 0; + const struct k_clock *kc = timer->kclock; - if (hrtimer_try_to_cancel(&timer->it.real.timer) < 0) + timer->it_interval = 0; + if (kc->timer_try_to_cancel(timer) < 0) return TIMER_RETRY; timer->it_active = 0; return 0; @@ -1063,76 +1074,84 @@ long clock_nanosleep_restart(struct restart_block *restart_block) } static const struct k_clock clock_realtime = { - .clock_getres = posix_get_hrtimer_res, - .clock_get = posix_clock_realtime_get, - .clock_set = posix_clock_realtime_set, - .clock_adj = posix_clock_realtime_adj, - .nsleep = common_nsleep, - .nsleep_restart = hrtimer_nanosleep_restart, - .timer_create = common_timer_create, - .timer_set = common_timer_set, - .timer_get = common_timer_get, - .timer_del = common_timer_del, - .timer_rearm = common_hrtimer_rearm, - .timer_forward = common_hrtimer_forward, - .timer_remaining= common_hrtimer_remaining, + .clock_getres = posix_get_hrtimer_res, + .clock_get = posix_clock_realtime_get, + .clock_set = posix_clock_realtime_set, + .clock_adj = posix_clock_realtime_adj, + .nsleep = common_nsleep, + .nsleep_restart = hrtimer_nanosleep_restart, + .timer_create = common_timer_create, + .timer_set = common_timer_set, + .timer_get = common_timer_get, + .timer_del = common_timer_del, + .timer_rearm = common_hrtimer_rearm, + .timer_forward = common_hrtimer_forward, + .timer_remaining = common_hrtimer_remaining, + .timer_try_to_cancel = common_hrtimer_try_to_cancel, + .timer_arm = common_hrtimer_arm, }; static const struct k_clock clock_monotonic = { - .clock_getres = posix_get_hrtimer_res, - .clock_get = posix_ktime_get_ts, - .nsleep = common_nsleep, - .nsleep_restart = hrtimer_nanosleep_restart, - .timer_create = common_timer_create, - .timer_set = common_timer_set, - .timer_get = common_timer_get, - .timer_del = common_timer_del, - .timer_rearm = common_hrtimer_rearm, - .timer_forward = common_hrtimer_forward, - .timer_remaining= common_hrtimer_remaining, + .clock_getres = posix_get_hrtimer_res, + .clock_get = posix_ktime_get_ts, + .nsleep = common_nsleep, + .nsleep_restart = hrtimer_nanosleep_restart, + .timer_create = common_timer_create, + .timer_set = common_timer_set, + .timer_get = common_timer_get, + .timer_del = common_timer_del, + .timer_rearm = common_hrtimer_rearm, + .timer_forward = common_hrtimer_forward, + .timer_remaining = common_hrtimer_remaining, + .timer_try_to_cancel = common_hrtimer_try_to_cancel, + .timer_arm = common_hrtimer_arm, }; static const struct k_clock clock_monotonic_raw = { - .clock_getres = posix_get_hrtimer_res, - .clock_get = posix_get_monotonic_raw, + .clock_getres = posix_get_hrtimer_res, + .clock_get = posix_get_monotonic_raw, }; static const struct k_clock clock_realtime_coarse = { - .clock_getres = posix_get_coarse_res, - .clock_get = posix_get_realtime_coarse, + .clock_getres = posix_get_coarse_res, + .clock_get = posix_get_realtime_coarse, }; static const struct k_clock clock_monotonic_coarse = { - .clock_getres = posix_get_coarse_res, - .clock_get = posix_get_monotonic_coarse, + .clock_getres = posix_get_coarse_res, + .clock_get = posix_get_monotonic_coarse, }; static const struct k_clock clock_tai = { - .clock_getres = posix_get_hrtimer_res, - .clock_get = posix_get_tai, - .nsleep = common_nsleep, - .nsleep_restart = hrtimer_nanosleep_restart, - .timer_create = common_timer_create, - .timer_set = common_timer_set, - .timer_get = common_timer_get, - .timer_del = common_timer_del, - .timer_rearm = common_hrtimer_rearm, - .timer_forward = common_hrtimer_forward, - .timer_remaining= common_hrtimer_remaining, + .clock_getres = posix_get_hrtimer_res, + .clock_get = posix_get_tai, + .nsleep = common_nsleep, + .nsleep_restart = hrtimer_nanosleep_restart, + .timer_create = common_timer_create, + .timer_set = common_timer_set, + .timer_get = common_timer_get, + .timer_del = common_timer_del, + .timer_rearm = common_hrtimer_rearm, + .timer_forward = common_hrtimer_forward, + .timer_remaining = common_hrtimer_remaining, + .timer_try_to_cancel = common_hrtimer_try_to_cancel, + .timer_arm = common_hrtimer_arm, }; static const struct k_clock clock_boottime = { - .clock_getres = posix_get_hrtimer_res, - .clock_get = posix_get_boottime, - .nsleep = common_nsleep, - .nsleep_restart = hrtimer_nanosleep_restart, - .timer_create = common_timer_create, - .timer_set = common_timer_set, - .timer_get = common_timer_get, - .timer_del = common_timer_del, - .timer_rearm = common_hrtimer_rearm, - .timer_forward = common_hrtimer_forward, - .timer_remaining= common_hrtimer_remaining, + .clock_getres = posix_get_hrtimer_res, + .clock_get = posix_get_boottime, + .nsleep = common_nsleep, + .nsleep_restart = hrtimer_nanosleep_restart, + .timer_create = common_timer_create, + .timer_set = common_timer_set, + .timer_get = common_timer_get, + .timer_del = common_timer_del, + .timer_rearm = common_hrtimer_rearm, + .timer_forward = common_hrtimer_forward, + .timer_remaining = common_hrtimer_remaining, + .timer_try_to_cancel = common_hrtimer_try_to_cancel, + .timer_arm = common_hrtimer_arm, }; static const struct k_clock * const posix_clocks[] = { -- 2.20.1