diff mbox

blk-mq: don't clear RQF_MQ_INFLIGHT in blk_mq_rq_ctx_init()

Message ID 5fd4a57e-cc9a-e3da-fe3b-1db2460423f8@kernel.dk (mailing list archive)
State New, archived
Headers show

Commit Message

Jens Axboe Jan. 14, 2018, 5:38 p.m. UTC 
On 1/13/18 10:49 AM, Ming Lei wrote:
> In case of no IO scheduler, RQF_MQ_INFLIGHT is set in blk_mq_rq_ctx_init(),
> but 7c3fb70f0341 clears it mistakenly, so fix it.

Oops yeah, that's my bad. However, I think the below fix is cleaner
and avoids a conditional.

Comments

Mike Snitzer Jan. 14, 2018, 5:43 p.m. UTC | #1 
On Sun, Jan 14 2018 at 12:38pm -0500,
Jens Axboe <axboe@kernel.dk> wrote:

> On 1/13/18 10:49 AM, Ming Lei wrote:
> > In case of no IO scheduler, RQF_MQ_INFLIGHT is set in blk_mq_rq_ctx_init(),
> > but 7c3fb70f0341 clears it mistakenly, so fix it.
> 
> Oops yeah, that's my bad. However, I think the below fix is cleaner
> and avoids a conditional.
> 
> 
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index b3b2003b7429..c8f62e6be6b6 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -269,13 +269,14 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
>  {
>  	struct blk_mq_tags *tags = blk_mq_tags_from_data(data);
>  	struct request *rq = tags->static_rqs[tag];
> +	req_flags_t rq_flags = 0;
>  
>  	if (data->flags & BLK_MQ_REQ_INTERNAL) {
>  		rq->tag = -1;
>  		rq->internal_tag = tag;
>  	} else {
>  		if (blk_mq_tag_busy(data->hctx)) {
> -			rq->rq_flags = RQF_MQ_INFLIGHT;
> +			rq_flags = RQF_MQ_INFLIGHT;
>  			atomic_inc(&data->hctx->nr_active);
>  		}
>  		rq->tag = tag;
> @@ -286,7 +287,7 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
>  	/* csd/requeue_work/fifo_time is initialized before use */
>  	rq->q = data->q;
>  	rq->mq_ctx = data->ctx;
> -	rq->rq_flags = 0;
> +	rq->rq_flags = rq_flags;
>  	rq->cpu = -1;
>  	rq->cmd_flags = op;
>  	if (data->flags & BLK_MQ_REQ_PREEMPT)

Yeap, looks good.

Reviewed-by:  Mike Snitzer <snitzer@redhat.com>

Defintely need this fix, without it all my dm-mpath testing hangs

Thanks,
Mike
Jens Axboe Jan. 14, 2018, 5:47 p.m. UTC | #2 
On 1/14/18 10:43 AM, Mike Snitzer wrote:
> On Sun, Jan 14 2018 at 12:38pm -0500,
> Jens Axboe <axboe@kernel.dk> wrote:
> 
>> On 1/13/18 10:49 AM, Ming Lei wrote:
>>> In case of no IO scheduler, RQF_MQ_INFLIGHT is set in blk_mq_rq_ctx_init(),
>>> but 7c3fb70f0341 clears it mistakenly, so fix it.
>>
>> Oops yeah, that's my bad. However, I think the below fix is cleaner
>> and avoids a conditional.
>>
>>
>> diff --git a/block/blk-mq.c b/block/blk-mq.c
>> index b3b2003b7429..c8f62e6be6b6 100644
>> --- a/block/blk-mq.c
>> +++ b/block/blk-mq.c
>> @@ -269,13 +269,14 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
>>  {
>>  	struct blk_mq_tags *tags = blk_mq_tags_from_data(data);
>>  	struct request *rq = tags->static_rqs[tag];
>> +	req_flags_t rq_flags = 0;
>>  
>>  	if (data->flags & BLK_MQ_REQ_INTERNAL) {
>>  		rq->tag = -1;
>>  		rq->internal_tag = tag;
>>  	} else {
>>  		if (blk_mq_tag_busy(data->hctx)) {
>> -			rq->rq_flags = RQF_MQ_INFLIGHT;
>> +			rq_flags = RQF_MQ_INFLIGHT;
>>  			atomic_inc(&data->hctx->nr_active);
>>  		}
>>  		rq->tag = tag;
>> @@ -286,7 +287,7 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
>>  	/* csd/requeue_work/fifo_time is initialized before use */
>>  	rq->q = data->q;
>>  	rq->mq_ctx = data->ctx;
>> -	rq->rq_flags = 0;
>> +	rq->rq_flags = rq_flags;
>>  	rq->cpu = -1;
>>  	rq->cmd_flags = op;
>>  	if (data->flags & BLK_MQ_REQ_PREEMPT)
> 
> Yeap, looks good.
> 
> Reviewed-by:  Mike Snitzer <snitzer@redhat.com>
> 
> Defintely need this fix, without it all my dm-mpath testing hangs

Yeah, pretty unfortunate... I've applied it and pushed it out.
diff mbox

Patch

diff --git a/block/blk-mq.c b/block/blk-mq.c
index b3b2003b7429..c8f62e6be6b6 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -269,13 +269,14 @@  static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
 {
 	struct blk_mq_tags *tags = blk_mq_tags_from_data(data);
 	struct request *rq = tags->static_rqs[tag];
+	req_flags_t rq_flags = 0;
 
 	if (data->flags & BLK_MQ_REQ_INTERNAL) {
 		rq->tag = -1;
 		rq->internal_tag = tag;
 	} else {
 		if (blk_mq_tag_busy(data->hctx)) {
-			rq->rq_flags = RQF_MQ_INFLIGHT;
+			rq_flags = RQF_MQ_INFLIGHT;
 			atomic_inc(&data->hctx->nr_active);
 		}
 		rq->tag = tag;
@@ -286,7 +287,7 @@  static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
 	/* csd/requeue_work/fifo_time is initialized before use */
 	rq->q = data->q;
 	rq->mq_ctx = data->ctx;
-	rq->rq_flags = 0;
+	rq->rq_flags = rq_flags;
 	rq->cpu = -1;
 	rq->cmd_flags = op;
 	if (data->flags & BLK_MQ_REQ_PREEMPT)