From a11abb98388e23188f3915780f3a193fdc1e4ff0 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 5 May 2025 22:17:48 +0800 Subject: [PATCH] block: look up the elevator type in elevator_switch That makes the function nicely self-contained and can be used to avoid code duplication. Reviewed-by: Nilay Shroff Reviewed-by: Hannes Reinecke Signed-off-by: Christoph Hellwig Signed-off-by: Ming Lei Link: https://lore.kernel.org/r/20250505141805.2751237-11-ming.lei@redhat.com Signed-off-by: Jens Axboe --- block/blk-mq.c | 2 +- block/blk.h | 2 +- block/elevator.c | 18 ++++++++---------- 3 files changed, 10 insertions(+), 12 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 74f4b1d37376..84395cc3c012 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -5058,7 +5058,7 @@ static void blk_mq_elv_switch_back(struct list_head *head, kfree(qe); mutex_lock(&q->elevator_lock); - elevator_switch(q, t); + elevator_switch(q, t->elevator_name); /* drop the reference acquired in blk_mq_elv_switch_none */ elevator_put(t); mutex_unlock(&q->elevator_lock); diff --git a/block/blk.h b/block/blk.h index ff21f234b62f..678308c8a78f 100644 --- a/block/blk.h +++ b/block/blk.h @@ -322,7 +322,7 @@ bool blk_bio_list_merge(struct request_queue *q, struct list_head *list, bool blk_insert_flush(struct request *rq); -int elevator_switch(struct request_queue *q, struct elevator_type *new_e); +int elevator_switch(struct request_queue *q, const char *name); void elevator_disable(struct request_queue *q); void elevator_exit(struct request_queue *q); int elv_register_queue(struct request_queue *q, bool uevent); diff --git a/block/elevator.c b/block/elevator.c index 2e18513dcd73..286d240a3aef 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -621,13 +621,18 @@ void elevator_init_mq(struct request_queue *q) * If switching fails, we are most likely running out of memory and not able * to restore the old io scheduler, so leaving the io scheduler being none. */ -int elevator_switch(struct request_queue *q, struct elevator_type *new_e) +int elevator_switch(struct request_queue *q, const char *name) { + struct elevator_type *new_e; int ret; WARN_ON_ONCE(q->mq_freeze_depth == 0); lockdep_assert_held(&q->elevator_lock); + new_e = elevator_find_get(name); + if (!new_e) + return -EINVAL; + blk_mq_quiesce_queue(q); if (q->elevator) { @@ -654,6 +659,7 @@ out_unfreeze: new_e->elevator_name); } + elevator_put(new_e); return ret; } @@ -679,9 +685,6 @@ void elevator_disable(struct request_queue *q) */ static int elevator_change(struct request_queue *q, const char *elevator_name) { - struct elevator_type *e; - int ret; - /* Make sure queue is not in the middle of being removed */ if (!blk_queue_registered(q)) return -ENOENT; @@ -695,12 +698,7 @@ static int elevator_change(struct request_queue *q, const char *elevator_name) if (q->elevator && elevator_match(q->elevator->type, elevator_name)) return 0; - e = elevator_find_get(elevator_name); - if (!e) - return -EINVAL; - ret = elevator_switch(q, e); - elevator_put(e); - return ret; + return elevator_switch(q, elevator_name); } static void elv_iosched_load_module(char *elevator_name) -- 2.50.1