[tip:timers/core] posix-timers: Unify overrun/requeue_pending handling

tip-bot for Thomas Gleixner
2017-06-05T08:20:03Z

Commit-ID: af888d677a3f4473c198b4720319dd037f398b51
Gitweb: http://git.kernel.org/tip/af888d677a3f4473c198b4720319dd037f398b51
Author: Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Tue, 30 May 2017 23:15:42 +0200
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitDate: Sun, 4 Jun 2017 15:40:24 +0200

posix-timers: Unify overrun/requeue_pending handling

hrtimer based posix-timers and posix-cpu-timers handle the update of the
rearming and overflow related status fields differently.

Move that update to the common rearming code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20170530211656.484936964@linutronix.de

---
kernel/time/posix-cpu-timers.c | 18 +++++++-----------
kernel/time/posix-timers.c | 15 ++++++++-------
2 files changed, 15 insertions(+), 18 deletions(-)

diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index a77a792..1683e50 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -527,6 +527,7 @@ static void cpu_timer_fire(struct k_itimer *timer)
* ticking in case the signal is deliverable next time.
*/
posix_cpu_timer_schedule(timer);
+ ++timer->it_requeue_pending;
}
}

@@ -997,12 +998,12 @@ void posix_cpu_timer_schedule(struct k_itimer *timer)
cpu_clock_sample(timer->it_clock, p, &now);
bump_cpu_timer(timer, now);
if (unlikely(p->exit_state))
- goto out;
+ return;

/* Protect timer list r/w in arm_timer() */
sighand = lock_task_sighand(p, &flags);
if (!sighand)
- goto out;
+ return;
} else {
/*
* Protect arm_timer() and timer sampling in case of call to
@@ -1015,11 +1016,10 @@ void posix_cpu_timer_schedule(struct k_itimer *timer)
* We can't even collect a sample any more.
*/
timer->it.cpu.expires = 0;
- goto out;
+ return;
} else if (unlikely(p->exit_state) && thread_group_empty(p)) {
- unlock_task_sighand(p, &flags);
- /* Optimizations: if the process is dying, no need to rearm */
- goto out;
+ /* If the process is dying, no need to rearm */
+ goto unlock;
}
cpu_timer_sample_group(timer->it_clock, p, &now);
bump_cpu_timer(timer, now);
@@ -1031,12 +1031,8 @@ void posix_cpu_timer_schedule(struct k_itimer *timer)
*/
WARN_ON_ONCE(!irqs_disabled());
arm_timer(timer);
+unlock:
unlock_task_sighand(p, &flags);
-
-out:
- timer->it_overrun_last = timer->it_overrun;
- timer->it_overrun = -1;
- ++timer->it_requeue_pending;
}

/**
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index dee6a0d..79a00e0 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -291,10 +291,6 @@ static void schedule_next_timer(struct k_itimer *timr)
timr->it_overrun += (unsigned int) hrtimer_forward(timer,
timer->base->get_time(),
timr->it.real.interval);
-
- timr->it_overrun_last = timr->it_overrun;
- timr->it_overrun = -1;
- ++timr->it_requeue_pending;
hrtimer_restart(timer);
}

@@ -315,18 +311,23 @@ void do_schedule_next_timer(struct siginfo *info)
unsigned long flags;

timr = lock_timer(info->si_tid, &flags);
+ if (!timr)
+ return;

- if (timr && timr->it_requeue_pending == info->si_sys_private) {
+ if (timr->it_requeue_pending == info->si_sys_private) {
if (timr->it_clock < 0)
posix_cpu_timer_schedule(timr);
else
schedule_next_timer(timr);

+ timr->it_overrun_last = timr->it_overrun;
+ timr->it_overrun = -1;
+ ++timr->it_requeue_pending;
+
info->si_overrun += timr->it_overrun_last;
}

- if (timr)
- unlock_timer(timr, flags);
+ unlock_timer(timr, flags);
}

int posix_timer_event(struct k_itimer *timr, int si_private)