From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Bart Van Assche To: Jens Axboe CC: , Christoph Hellwig , "Bart Van Assche" , Hannes Reinecke , "Omar Sandoval" , Ming Lei Subject: [PATCH v3 10/12] blk-mq: Document locking assumptions Date: Thu, 8 Jun 2017 10:33:53 -0700 Message-ID: <20170608173355.25898-11-bart.vanassche@sandisk.com> In-Reply-To: <20170608173355.25898-1-bart.vanassche@sandisk.com> References: <20170608173355.25898-1-bart.vanassche@sandisk.com> MIME-Version: 1.0 Content-Type: text/plain Return-Path: Bart.VanAssche@sandisk.com List-ID: Document the locking assumptions in functions that modify blk_mq_ctx.rq_list to make it easier for humans to verify this code. Signed-off-by: Bart Van Assche Reviewed-by: Christoph Hellwig Cc: Hannes Reinecke Cc: Omar Sandoval Cc: Ming Lei --- block/blk-mq-sched.c | 2 ++ block/blk-mq.c | 4 ++++ 2 files changed, 6 insertions(+) diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index c4e2afb9d12d..88aa460b2e8a 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -232,6 +232,8 @@ static bool blk_mq_attempt_merge(struct request_queue *q, struct request *rq; int checked = 8; + lockdep_assert_held(&ctx->lock); + list_for_each_entry_reverse(rq, &ctx->rq_list, queuelist) { bool merged = false; diff --git a/block/blk-mq.c b/block/blk-mq.c index 5d9cca62c2f0..0f8c011eff97 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1274,6 +1274,8 @@ static inline void __blk_mq_insert_req_list(struct blk_mq_hw_ctx *hctx, { struct blk_mq_ctx *ctx = rq->mq_ctx; + lockdep_assert_held(&ctx->lock); + trace_block_rq_insert(hctx->queue, rq); if (at_head) @@ -1287,6 +1289,8 @@ void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq, { struct blk_mq_ctx *ctx = rq->mq_ctx; + lockdep_assert_held(&ctx->lock); + __blk_mq_insert_req_list(hctx, rq, at_head); blk_mq_hctx_mark_pending(hctx, ctx); } -- 2.12.2