diff mbox

[v4,06/12] blk-mq: Initialize .rq_flags in blk_mq_rq_ctx_init()

Message ID 20170619220801.12557-7-bart.vanassche@wdc.com (mailing list archive)
State New, archived
Headers show

Commit Message

Bart Van Assche June 19, 2017, 10:07 p.m. UTC 
From: Bart Van Assche <bart.vanassche@sandisk.com>

Initialization of blk-mq requests is a bit weird: blk_mq_rq_ctx_init()
is called after a value has been assigned to .rq_flags and .rq_flags
is initialized in __blk_mq_finish_request(). Initialize .rq_flags in
blk_mq_rq_ctx_init() instead of relying on __blk_mq_finish_request().
Moving the initialization of .rq_flags is fine because all changes
and tests of .rq_flags occur between blk_get_request() and finishing
a request.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Ming Lei <ming.lei@redhat.com>
---
 block/blk-mq.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Hannes Reinecke June 20, 2017, 6:39 a.m. UTC | #1 
On 06/20/2017 12:07 AM, Bart Van Assche wrote:
> From: Bart Van Assche <bart.vanassche@sandisk.com>
> 
> Initialization of blk-mq requests is a bit weird: blk_mq_rq_ctx_init()
> is called after a value has been assigned to .rq_flags and .rq_flags
> is initialized in __blk_mq_finish_request(). Initialize .rq_flags in
> blk_mq_rq_ctx_init() instead of relying on __blk_mq_finish_request().
> Moving the initialization of .rq_flags is fine because all changes
> and tests of .rq_flags occur between blk_get_request() and finishing
> a request.
> 
> Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
> Cc: Christoph Hellwig <hch@lst.de>
> Cc: Hannes Reinecke <hare@suse.com>
> Cc: Omar Sandoval <osandov@fb.com>
> Cc: Ming Lei <ming.lei@redhat.com>
> ---
>  block/blk-mq.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index 8cd423ba585d..679b52790bc1 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -260,6 +260,7 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
>  	rq->q = data->q;
>  	rq->mq_ctx = data->ctx;
>  	rq->cmd_flags = op;
> +	rq->rq_flags = 0;
>  	if (blk_queue_io_stat(data->q))
>  		rq->rq_flags |= RQF_IO_STAT;
>  	/* do not touch atomic flags, it needs atomic ops against the timer */
> @@ -435,7 +436,6 @@ void blk_mq_free_request(struct request *rq)
>  		atomic_dec(&hctx->nr_active);
>  
>  	wbt_done(q->rq_wb, &rq->issue_stat);
> -	rq->rq_flags = 0;
>  
>  	clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags);
>  	clear_bit(REQ_ATOM_POLL_SLEPT, &rq->atomic_flags);
> 
Reviewed-by: Hannes Reinecke <hare@suse.com>

Cheers,

Hannes
Christoph Hellwig June 20, 2017, 9:22 a.m. UTC | #2 
Looks fine,

Reviewed-by: Christoph Hellwig <hch@lst.de>
diff mbox

Patch

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 8cd423ba585d..679b52790bc1 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -260,6 +260,7 @@  static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
 	rq->q = data->q;
 	rq->mq_ctx = data->ctx;
 	rq->cmd_flags = op;
+	rq->rq_flags = 0;
 	if (blk_queue_io_stat(data->q))
 		rq->rq_flags |= RQF_IO_STAT;
 	/* do not touch atomic flags, it needs atomic ops against the timer */
@@ -435,7 +436,6 @@  void blk_mq_free_request(struct request *rq)
 		atomic_dec(&hctx->nr_active);
 
 	wbt_done(q->rq_wb, &rq->issue_stat);
-	rq->rq_flags = 0;
 
 	clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags);
 	clear_bit(REQ_ATOM_POLL_SLEPT, &rq->atomic_flags);