From fbd72127c975dc8e532ecc73d52f3b1b00935bec Mon Sep 17 00:00:00 2001 From: Aleksei Zakharov Date: Mon, 11 Feb 2019 13:50:37 +0300 Subject: [PATCH] block: avoid setting none scheduler if it's already none There's no reason to freeze queue and remove scheduler if there's no scheduler already. Signed-off-by: Aleksei Zakharov Signed-off-by: Jens Axboe --- block/elevator.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/block/elevator.c b/block/elevator.c index f05e90d4e695..d6d835a08de6 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -667,8 +667,11 @@ static int __elevator_change(struct request_queue *q, const char *name) /* * Special case for mq, turn off scheduling */ - if (!strncmp(name, "none", 4)) + if (!strncmp(name, "none", 4)) { + if (!q->elevator) + return 0; return elevator_switch(q, NULL); + } strlcpy(elevator_name, name, sizeof(elevator_name)); e = elevator_get(q, strstrip(elevator_name), true); -- 2.30.2