Merge "stop_machine: Disable preemption after queueing stopper threads" (2786b1dc) · Commits · e / devices / android_kernel_oneplus_sm8150

kernel/stop_machine.c

+9 −1

Original line number	Diff line number	Diff line
		@@ -260,6 +260,15 @@ static int cpu_stop_queue_two_works(int cpu1, struct cpu_stop_work *work1,
		err = 0;
		__cpu_stop_queue_work(stopper1, work1, &wakeq);
		__cpu_stop_queue_work(stopper2, work2, &wakeq);
		/*
		* The waking up of stopper threads has to happen
		* in the same scheduling context as the queueing.
		* Otherwise, there is a possibility of one of the
		* above stoppers being woken up by another CPU,
		* and preempting us. This will cause us to not
		* wake up the other stopper forever.
		*/
		preempt_disable();
		unlock:
		spin_unlock(&stopper2->lock);
		spin_unlock_irq(&stopper1->lock);
		@@ -271,7 +280,6 @@ static int cpu_stop_queue_two_works(int cpu1, struct cpu_stop_work *work1,
		}

		if (!err) {
		preempt_disable();
		wake_up_q(&wakeq);
		preempt_enable();
		}