diff options
| author | Anna-Maria Gleixner <anna-maria@linutronix.de> | 2019-07-31 00:33:51 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2019-08-01 20:51:24 +0200 |
| commit | c7e6d704a0097e59667495cf52dcc4e1085e620b (patch) | |
| tree | c3775ba9173d0cff6fee1dbb7aee1ecb13ab9e5a | |
| parent | a125ecc16453a4fe0ba865c7df87b9c722991fdf (diff) | |
itimers: Prepare for PREEMPT_RT
Use the hrtimer_cancel_wait_running() synchronization mechanism to prevent
priority inversion and live locks on PREEMPT_RT.
As a benefit the retry loop gains the missing cpu_relax() on !RT.
[ tglx: Split out of combo patch ]
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190730223828.690771827@linutronix.de
| -rw-r--r-- | kernel/time/itimer.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/kernel/time/itimer.c b/kernel/time/itimer.c index 02068b2d5862..9d26fd4ba4c0 100644 --- a/kernel/time/itimer.c +++ b/kernel/time/itimer.c @@ -213,6 +213,7 @@ again: /* We are sharing ->siglock with it_real_fn() */ if (hrtimer_try_to_cancel(timer) < 0) { spin_unlock_irq(&tsk->sighand->siglock); + hrtimer_cancel_wait_running(timer); goto again; } expires = timeval_to_ktime(value->it_value); |