From e0cca8bc9cd8d6176921cb3f5f466d3ccfbc6b99 Mon Sep 17 00:00:00 2001 From: Jinlong Chen Date: Tue, 22 Nov 2022 22:21:24 +0800 Subject: [PATCH] elevator: printk a warning if switching to a new io scheduler fails printk a warning to indicate that the io scheduler has been set to none if switching to a new io scheduler fails. Suggested-by: Christoph Hellwig Signed-off-by: Jinlong Chen Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/d51ed0fb457db7a4f9cbb0dbce36d534e22be457.1669126766.git.nickyc975@zju.edu.cn Signed-off-by: Jens Axboe --- block/elevator.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/block/elevator.c b/block/elevator.c index 01aa9f38f22e..1fa45717b1d6 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -683,6 +683,12 @@ int elevator_switch(struct request_queue *q, struct elevator_type *new_e) out_unfreeze: blk_mq_unquiesce_queue(q); blk_mq_unfreeze_queue(q); + + if (ret) { + pr_warn("elv: switch to \"%s\" failed, falling back to \"none\"\n", + new_e->elevator_name); + } + return ret; }