From: Minchan Kim <minchan@kernel.org>
Date: Thu, 30 Mar 2017 05:20:45 +0000 (+0900)
Subject: block: do not put mq context in blk_mq_alloc_request_hctx
X-Git-Tag: v4.12-rc1~175^2~232
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=3e06eb3dacdff52749df85694cf6bc48283973c6;p=linux.git

block: do not put mq context in blk_mq_alloc_request_hctx

In blk_mq_alloc_request_hctx, blk_mq_sched_get_request doesn't
get sw context so we don't need to put the context with
blk_mq_put_ctx. Unless, we will see preempt counter underflow.

Cc: Omar Sandoval <osandov@fb.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
---

diff --git a/block/blk-mq.c b/block/blk-mq.c
index e6ac774b0e41..ef63367077ad 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -324,7 +324,6 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q, int rw,
 
 	rq = blk_mq_sched_get_request(q, NULL, rw, &alloc_data);
 
-	blk_mq_put_ctx(alloc_data.ctx);
 	blk_queue_exit(q);
 
 	if (!rq)