Commit a125ecc1 authored Jul 31, 2019 by Anna-Maria Gleixner Committed by Thomas Gleixner Aug 01, 2019

timerfd: Prepare for PREEMPT_RT



Use the hrtimer_cancel_wait_running() synchronization mechanism to prevent
priority inversion and live locks on PREEMPT_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/20190730223828.600085866@linutronix.de

parent 51ae3309

fs/timerfd.c

+5 −1

Original line number	Diff line number	Diff line
		@@ -471,7 +471,11 @@ static int do_timerfd_settime(int ufd, int flags,
		break;
		}
		spin_unlock_irq(&ctx->wqh.lock);
		cpu_relax();

		if (isalarm(ctx))
		hrtimer_cancel_wait_running(&ctx->t.alarm.timer);
		else
		hrtimer_cancel_wait_running(&ctx->t.tmr);
		}

		/*

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