block: avoid setting nr_requests to current value

BugLink: https://bugs.launchpad.net/bugs/1815733
There's no reason to freeze queue and set nr_requests value
if current value is the same.

Signed-off-by: Aleksei Zakharov <zakharov.a.g@yandex.ru>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
(backported from commit e5fa81408fb43ebabde65938ef8b20ae879017e7)
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Acked-by: Kleber Souza <kleber.souza@canonical.com>
Acked-by: AceLan Kao <acelan.kao@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 2f8436314985574cfd0c237b31e5290c86b53fa1..67a80fd597e1405133ea3b4b27e3a69877d9bc47 100644 (file)
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2792,6 +2792,9 @@ int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr)
        if (!set)
                return -EINVAL;
 
+       if (q->nr_requests == nr)
+               return 0;
+
        blk_mq_freeze_queue(q);
 
        ret = 0;