Messages in this thread Patch in this message | | | From | Sebastian Andrzej Siewior <> | Subject | [PATCH RT 2/3] posix-timers: user proper timer while waiting for alarmtimer | Date | Wed, 28 Mar 2018 12:07:45 +0200 |
| |
On RT the timer can be preempted while running and therefore we wait with timer_wait_for_callback() for the timer to complete (instead of busy looping). The POSIX timer has an hrtimer underneath and this hrtimer is used to wait for its completion. The alartimer has also an hrtimer but at a different location.
Instead of checking for ->timer_set which is the same for the alarmtimer and the "posix-timers" I instead check for ->arm which is only used by the "posix-timers". To match the alarmtimer I check for the alarm_clock struct.
Cc: stable-rt@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> --- kernel/time/posix-timers.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c index 0b568087bd64..8a16cb8f684a 100644 --- a/kernel/time/posix-timers.c +++ b/kernel/time/posix-timers.c @@ -802,8 +802,10 @@ SYSCALL_DEFINE1(timer_getoverrun, timer_t, timer_id) static void timer_wait_for_callback(const struct k_clock *kc, struct k_itimer *timr) { #ifdef CONFIG_PREEMPT_RT_FULL - if (kc->timer_set == common_timer_set) + if (kc->arm == common_hrtimer_arm) hrtimer_wait_for_timer(&timr->it.real.timer); + else if (kc == alarm_clock) + hrtimer_wait_for_timer(&timr->it.alarm.alarmtimer.timer); else /* FIXME: Whacky hack for posix-cpu-timers */ schedule_timeout(1); -- 2.16.3
| |