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| author | Ming Lei <ming.lei@redhat.com> | 2025-05-05 22:17:52 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2025-05-06 07:43:43 -0600 |
| commit | 20117b5a4b9c6dbb9414f0451111c3f13a37874a (patch) | |
| tree | e58016158bac677eeed18aec616721d21ce55466 /block/elevator.c | |
| parent | 596dce110b7d543db727e6957ae7adf35beb0633 (diff) | |
| download | linux-20117b5a4b9c6dbb9414f0451111c3f13a37874a.tar.gz linux-20117b5a4b9c6dbb9414f0451111c3f13a37874a.tar.bz2 linux-20117b5a4b9c6dbb9414f0451111c3f13a37874a.zip | |
block: move queue freezing & elevator_lock into elevator_change()
Move queue freezing & elevator_lock into elevator_change(), and prepare
for using elevator_change() for setting up & tearing down default elevator
too.
Also add lockdep_assert_held() in __elevator_change() because either
read or write lock is required for changing elevator.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-15-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/elevator.c')
| -rw-r--r-- | block/elevator.c | 20 |
1 files changed, 12 insertions, 8 deletions
diff --git a/block/elevator.c b/block/elevator.c index cabd7a8bb76c..cb54a3791fe5 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -676,10 +676,19 @@ out_unfreeze: */ static int elevator_change(struct request_queue *q, const char *elevator_name) { - if (q->elevator && elevator_match(q->elevator->type, elevator_name)) - return 0; + unsigned int memflags; + int ret = 0; - return elevator_switch(q, elevator_name); + lockdep_assert_held(&q->tag_set->update_nr_hwq_lock); + + memflags = blk_mq_freeze_queue(q); + mutex_lock(&q->elevator_lock); + if (!(q->elevator && elevator_match(q->elevator->type, + elevator_name))) + ret = elevator_switch(q, elevator_name); + mutex_unlock(&q->elevator_lock); + blk_mq_unfreeze_queue(q, memflags); + return ret; } /* @@ -718,7 +727,6 @@ ssize_t elv_iosched_store(struct gendisk *disk, const char *buf, char elevator_name[ELV_NAME_MAX]; char *name; int ret; - unsigned int memflags; struct request_queue *q = disk->queue; struct blk_mq_tag_set *set = q->tag_set; @@ -737,13 +745,9 @@ ssize_t elv_iosched_store(struct gendisk *disk, const char *buf, elv_iosched_load_module(name); down_read(&set->update_nr_hwq_lock); - memflags = blk_mq_freeze_queue(q); - mutex_lock(&q->elevator_lock); ret = elevator_change(q, name); if (!ret) ret = count; - mutex_unlock(&q->elevator_lock); - blk_mq_unfreeze_queue(q, memflags); up_read(&set->update_nr_hwq_lock); return ret; } |