[ Upstream commit bcc816dfe51ab86ca94663c7b225f2d6eb0fddb9 ]
We would never be able to sort the list if we first reset plug->rq_count which is used in conditional check later.
Fixes: ce5b009cff19 ("block: improve logic around when to sort a plug list") Reviewed-by: Ming Lei ming.lei@redhat.com Signed-off-by: Dongli Zhang dongli.zhang@oracle.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin (Microsoft) sashal@kernel.org --- block/blk-mq.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c index 97eba6d23425..5a2585d69c81 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1716,11 +1716,12 @@ void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) unsigned int depth;
list_splice_init(&plug->mq_list, &list); - plug->rq_count = 0;
if (plug->rq_count > 2 && plug->multiple_queues) list_sort(NULL, &list, plug_rq_cmp);
+ plug->rq_count = 0; + this_q = NULL; this_hctx = NULL; this_ctx = NULL;