Merge "cfq: fix starvation of asynchronous writes" (e701f80b) · Commits · e / devices / android_kernel_xiaomi_markw

block/cfq-iosched.c

+10 −3

Original line number	Diff line number	Diff line
		@@ -2827,7 +2827,6 @@ static struct request cfq_check_fifo(struct cfq_queue cfqq)
		if (time_before(jiffies, rq->fifo_time))
		rq = NULL;

		cfq_log_cfqq(cfqq->cfqd, cfqq, "fifo=%p", rq);
		return rq;
		}

		@@ -3201,6 +3200,9 @@ static bool cfq_may_dispatch(struct cfq_data cfqd, struct cfq_queue cfqq)
		{
		unsigned int max_dispatch;

		if (cfq_cfqq_must_dispatch(cfqq))
		return true;

		/*
		* Drain async requests before we start sync IO
		*/
		@@ -3292,15 +3294,20 @@ static bool cfq_dispatch_request(struct cfq_data cfqd, struct cfq_queue cfqq)

		BUG_ON(RB_EMPTY_ROOT(&cfqq->sort_list));

		rq = cfq_check_fifo(cfqq);
		if (rq)
		cfq_mark_cfqq_must_dispatch(cfqq);

		if (!cfq_may_dispatch(cfqd, cfqq))
		return false;

		/*
		* follow expired path, else get first next available
		*/
		rq = cfq_check_fifo(cfqq);
		if (!rq)
		rq = cfqq->next_rq;
		else
		cfq_log_cfqq(cfqq->cfqd, cfqq, "fifo=%p", rq);

		/*
		* insert request into driver dispatch list
		@@ -3809,7 +3816,7 @@ cfq_should_preempt(struct cfq_data cfqd, struct cfq_queue new_cfqq,
		* if the new request is sync, but the currently running queue is
		* not, let the sync request have priority.
		*/
		if (rq_is_sync(rq) && !cfq_cfqq_sync(cfqq))
		if (rq_is_sync(rq) && !cfq_cfqq_sync(cfqq) && !cfq_cfqq_must_dispatch(cfqq))
		return true;

		if (new_cfqq->cfqg != cfqq->cfqg)