Commit b7882093 authored by Jens Axboe's avatar Jens Axboe
Browse files

blk-wbt: use wq_has_sleeper() for wq active check 



We need the memory barrier before checking the list head,
use the appropriate helper for this. The matching queue
side memory barrier is provided by set_current_state().

Tested-by: default avatarAnchal Agarwal <anchalag@amazon.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent ffa358dc

block/blk-wbt.c

+4 −4
Original line number Diff line number Diff line
@@ -118,7 +118,7 @@ static void rwb_wake_all(struct rq_wb *rwb) 
	for (i = 0; i < WBT_NUM_RWQ; i++) {

		struct rq_wait *rqw = &rwb->rq_wait[i];



		if (waitqueue_active(&rqw->wait))

		if (wq_has_sleeper(&rqw->wait))

			wake_up_all(&rqw->wait);

	}

}
@@ -162,7 +162,7 @@ static void __wbt_done(struct rq_qos *rqos, enum wbt_flags wb_acct) 
	if (inflight && inflight >= limit)

		return;



	if (waitqueue_active(&rqw->wait)) {

	if (wq_has_sleeper(&rqw->wait)) {

		int diff = limit - inflight;



		if (!inflight || diff >= rwb->wb_background / 2)
@@ -493,8 +493,8 @@ static void __wbt_wait(struct rq_wb *rwb, enum wbt_flags wb_acct, 
	struct rq_wait *rqw = get_rq_wait(rwb, wb_acct);

	DECLARE_WAITQUEUE(wait, current);



	if (!waitqueue_active(&rqw->wait)

		&& rq_wait_inc_below(rqw, get_limit(rwb, rw)))

	if (!wq_has_sleeper(&rqw->wait) &&

	    rq_wait_inc_below(rqw, get_limit(rwb, rw)))

		return;



	add_wait_queue_exclusive(&rqw->wait, &wait);