Commit 6bae363e authored by Keith Busch's avatar Keith Busch Committed by Jens Axboe
Browse files

blk-mq: Export blk_mq_freeze_queue_wait 



Drivers can start a freeze, so this provides a way to wait for frozen.

Signed-off-by: default avatarKeith Busch <keith.busch@intel.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarSagi Grimberg <sagi@grimberg.me>
Signed-off-by: default avatarJens Axboe <axboe@fb.com>
parent 6a8a2154

block/blk-mq.c

+2 −1
Original line number Diff line number Diff line
@@ -75,10 +75,11 @@ void blk_mq_freeze_queue_start(struct request_queue *q) 
}

EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_start);



static void blk_mq_freeze_queue_wait(struct request_queue *q)

void blk_mq_freeze_queue_wait(struct request_queue *q)

{

	wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->q_usage_counter));

}

EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_wait);



/*

 * Guarantee no request is in use, so we can change any data structure of

include/linux/blk-mq.h

+1 −0
Original line number Diff line number Diff line
@@ -245,6 +245,7 @@ void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset, 
void blk_mq_freeze_queue(struct request_queue *q);

void blk_mq_unfreeze_queue(struct request_queue *q);

void blk_mq_freeze_queue_start(struct request_queue *q);

void blk_mq_freeze_queue_wait(struct request_queue *q);

int blk_mq_reinit_tagset(struct blk_mq_tag_set *set);



int blk_mq_map_queues(struct blk_mq_tag_set *set);