| Message ID | 20200630022356.2149607-4-ming.lei@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | blk-mq: driver tag related cleanup | expand |
> index 21108a550fbf..3b0c5cfe922a 100644 > --- a/block/blk-flush.c > +++ b/block/blk-flush.c > @@ -236,12 +236,10 @@ static void flush_end_io(struct request *flush_rq, blk_status_t error) > error = fq->rq_status; > > hctx = flush_rq->mq_hctx; > + if (!q->elevator) > flush_rq->tag = -1; > + else > flush_rq->internal_tag = -1; These should switch to BLK_MQ_NO_TAG which you're at it. > - if (!(data->flags & BLK_MQ_REQ_INTERNAL)) > - blk_mq_tag_busy(data->hctx); BLK_MQ_REQ_INTERNAL is gone now, so this won't apply. > static bool blk_mq_get_driver_tag(struct request *rq) > { > + struct blk_mq_hw_ctx *hctx = rq->mq_hctx; > + bool shared = blk_mq_tag_busy(rq->mq_hctx); > + > + if (rq->tag == BLK_MQ_NO_TAG && !__blk_mq_get_driver_tag(rq)) > + return false; > + > + if (shared) { > + rq->rq_flags |= RQF_MQ_INFLIGHT; > + atomic_inc(&hctx->nr_active); > + } > + hctx->tags->rqs[rq->tag] = rq; > + return true; > } The function seems a bit misnamed now, although I don't have a good suggestion for a better name.
On Tue, Jun 30, 2020 at 06:05:57AM +0100, Christoph Hellwig wrote: > > index 21108a550fbf..3b0c5cfe922a 100644 > > --- a/block/blk-flush.c > > +++ b/block/blk-flush.c > > @@ -236,12 +236,10 @@ static void flush_end_io(struct request *flush_rq, blk_status_t error) > > error = fq->rq_status; > > > > hctx = flush_rq->mq_hctx; > > + if (!q->elevator) > > flush_rq->tag = -1; > > + else > > flush_rq->internal_tag = -1; > > These should switch to BLK_MQ_NO_TAG which you're at it. OK, we can do that in this patch. > > > - if (!(data->flags & BLK_MQ_REQ_INTERNAL)) > > - blk_mq_tag_busy(data->hctx); > > BLK_MQ_REQ_INTERNAL is gone now, so this won't apply. blk_mq_tag_busy() is needed for either none and io scheduler, so it is moved into blk_mq_get_driver_tag(), then check on BLK_MQ_REQ_INTERNAL is gone. > > > static bool blk_mq_get_driver_tag(struct request *rq) > > { > > + struct blk_mq_hw_ctx *hctx = rq->mq_hctx; > > + bool shared = blk_mq_tag_busy(rq->mq_hctx); > > + > > + if (rq->tag == BLK_MQ_NO_TAG && !__blk_mq_get_driver_tag(rq)) > > + return false; > > + > > + if (shared) { > > + rq->rq_flags |= RQF_MQ_INFLIGHT; > > + atomic_inc(&hctx->nr_active); > > + } > > + hctx->tags->rqs[rq->tag] = rq; > > + return true; > > } > > The function seems a bit misnamed now, although I don't have a good > suggestion for a better name. I think it is fine to leave it as-is, since what the patch does is just to move blk_mq_tag_busy() & the RQF_MQ_INFLIGHT part from __blk_mq_get_driver_tag to blk_mq_get_driver_tag(). Thanks, Ming
On 6/30/20 4:23 AM, Ming Lei wrote: > Move blk_mq_tag_busy(), .nr_active update and request assignment into > blk_mq_get_driver_tag(), all are good to do during getting driver tag. > > Meantime blk-flush related code is simplified and flush request needn't > to update the request table manually any more. > > Cc: Christoph Hellwig <hch@infradead.org> > Signed-off-by: Ming Lei <ming.lei@redhat.com> > --- > block/blk-flush.c | 13 ++++--------- > block/blk-mq-tag.h | 12 ------------ > block/blk-mq.c | 33 +++++++++++++-------------------- > block/blk.h | 5 ----- > 4 files changed, 17 insertions(+), 46 deletions(-) > > diff --git a/block/blk-flush.c b/block/blk-flush.c > index 21108a550fbf..3b0c5cfe922a 100644 > --- a/block/blk-flush.c > +++ b/block/blk-flush.c > @@ -236,12 +236,10 @@ static void flush_end_io(struct request *flush_rq, blk_status_t error) > error = fq->rq_status; > > hctx = flush_rq->mq_hctx; > - if (!q->elevator) { > - blk_mq_tag_set_rq(hctx, flush_rq->tag, fq->orig_rq); > + if (!q->elevator) > flush_rq->tag = -1; > - } else { > + else > flush_rq->internal_tag = -1; > - } > > running = &fq->flush_queue[fq->flush_running_idx]; > BUG_ON(fq->flush_pending_idx == fq->flush_running_idx); > @@ -315,13 +313,10 @@ static void blk_kick_flush(struct request_queue *q, struct blk_flush_queue *fq, > flush_rq->mq_ctx = first_rq->mq_ctx; > flush_rq->mq_hctx = first_rq->mq_hctx; > > - if (!q->elevator) { > - fq->orig_rq = first_rq; > + if (!q->elevator) > flush_rq->tag = first_rq->tag; > - blk_mq_tag_set_rq(flush_rq->mq_hctx, first_rq->tag, flush_rq); > - } else { > + else > flush_rq->internal_tag = first_rq->internal_tag; > - } > > flush_rq->cmd_flags = REQ_OP_FLUSH | REQ_PREFLUSH; > flush_rq->cmd_flags |= (flags & REQ_DRV) | (flags & REQ_FAILFAST_MASK); > diff --git a/block/blk-mq-tag.h b/block/blk-mq-tag.h > index 3945c7f5b944..b1acac518c4e 100644 > --- a/block/blk-mq-tag.h > +++ b/block/blk-mq-tag.h > @@ -101,18 +101,6 @@ static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, > return atomic_read(&hctx->nr_active) < depth; > } > > -/* > - * This helper should only be used for flush request to share tag > - * with the request cloned from, and both the two requests can't be > - * in flight at the same time. The caller has to make sure the tag > - * can't be freed. > - */ > -static inline void blk_mq_tag_set_rq(struct blk_mq_hw_ctx *hctx, > - unsigned int tag, struct request *rq) > -{ > - hctx->tags->rqs[tag] = rq; > -} > - > static inline bool blk_mq_tag_is_reserved(struct blk_mq_tags *tags, > unsigned int tag) > { > diff --git a/block/blk-mq.c b/block/blk-mq.c > index cabeeeb3d56c..44b101757d33 100644 > --- a/block/blk-mq.c > +++ b/block/blk-mq.c > @@ -277,26 +277,20 @@ 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 = BLK_MQ_NO_TAG; > rq->internal_tag = tag; > } else { > - if (data->hctx->flags & BLK_MQ_F_TAG_SHARED) { > - rq_flags = RQF_MQ_INFLIGHT; > - atomic_inc(&data->hctx->nr_active); > - } > rq->tag = tag; > rq->internal_tag = BLK_MQ_NO_TAG; > - data->hctx->tags->rqs[rq->tag] = rq; > } > > /* csd/requeue_work/fifo_time is initialized before use */ > rq->q = data->q; > rq->mq_ctx = data->ctx; > rq->mq_hctx = data->hctx; > - rq->rq_flags = rq_flags; > + rq->rq_flags = 0; > rq->cmd_flags = data->cmd_flags; > if (data->flags & BLK_MQ_REQ_PREEMPT) > rq->rq_flags |= RQF_PREEMPT; > @@ -380,8 +374,6 @@ static struct request *__blk_mq_alloc_request(struct blk_mq_alloc_data *data) > retry: > data->ctx = blk_mq_get_ctx(q); > data->hctx = blk_mq_map_queue(q, data->cmd_flags, data->ctx); > - if (!(data->flags & BLK_MQ_REQ_INTERNAL)) > - blk_mq_tag_busy(data->hctx); > > /* > * Waiting allocations only fail because of an inactive hctx. In that > @@ -478,8 +470,6 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q, > > if (q->elevator) > data.flags |= BLK_MQ_REQ_INTERNAL; > - else > - blk_mq_tag_busy(data.hctx); > > ret = -EWOULDBLOCK; > tag = blk_mq_get_tag(&data); > @@ -1131,7 +1121,6 @@ static bool __blk_mq_get_driver_tag(struct request *rq) > { > struct sbitmap_queue *bt = &rq->mq_hctx->tags->bitmap_tags; > unsigned int tag_offset = rq->mq_hctx->tags->nr_reserved_tags; > - bool shared = blk_mq_tag_busy(rq->mq_hctx); > int tag; > > if (blk_mq_tag_is_reserved(rq->mq_hctx->sched_tags, rq->internal_tag)) { > @@ -1146,19 +1135,23 @@ static bool __blk_mq_get_driver_tag(struct request *rq) > return false; > > rq->tag = tag + tag_offset; > - if (shared) { > - rq->rq_flags |= RQF_MQ_INFLIGHT; > - atomic_inc(&rq->mq_hctx->nr_active); > - } > - rq->mq_hctx->tags->rqs[rq->tag] = rq; > return true; > } > > static bool blk_mq_get_driver_tag(struct request *rq) > { > - if (rq->tag != BLK_MQ_NO_TAG) > - return true; > - return __blk_mq_get_driver_tag(rq); > + struct blk_mq_hw_ctx *hctx = rq->mq_hctx; > + bool shared = blk_mq_tag_busy(rq->mq_hctx); > + > + if (rq->tag == BLK_MQ_NO_TAG && !__blk_mq_get_driver_tag(rq)) > + return false; > + > + if (shared) { > + rq->rq_flags |= RQF_MQ_INFLIGHT; > + atomic_inc(&hctx->nr_active); > + } > + hctx->tags->rqs[rq->tag] = rq; > + return true; > } > > static int blk_mq_dispatch_wake(wait_queue_entry_t *wait, unsigned mode, > diff --git a/block/blk.h b/block/blk.h > index 3a120a070dac..459790f9783d 100644 > --- a/block/blk.h > +++ b/block/blk.h > @@ -25,11 +25,6 @@ struct blk_flush_queue { > struct list_head flush_data_in_flight; > struct request *flush_rq; > > - /* > - * flush_rq shares tag with this rq, both can't be active > - * at the same time > - */ > - struct request *orig_rq; > struct lock_class_key key; > spinlock_t mq_flush_lock; > }; > Can you give some more explanation why it's safe to move blk_mq_tag_busy() into blk_mq_get_driver_tag(), seeing that it was called before blk_mq_get_tag() initially? Cheers, Hannes
On Tue, Jun 30, 2020 at 08:26:11AM +0200, Hannes Reinecke wrote: > On 6/30/20 4:23 AM, Ming Lei wrote: > > Move blk_mq_tag_busy(), .nr_active update and request assignment into > > blk_mq_get_driver_tag(), all are good to do during getting driver tag. > > > > Meantime blk-flush related code is simplified and flush request needn't > > to update the request table manually any more. > > > > Cc: Christoph Hellwig <hch@infradead.org> > > Signed-off-by: Ming Lei <ming.lei@redhat.com> > > --- > > block/blk-flush.c | 13 ++++--------- > > block/blk-mq-tag.h | 12 ------------ > > block/blk-mq.c | 33 +++++++++++++-------------------- > > block/blk.h | 5 ----- > > 4 files changed, 17 insertions(+), 46 deletions(-) > > > > diff --git a/block/blk-flush.c b/block/blk-flush.c > > index 21108a550fbf..3b0c5cfe922a 100644 > > --- a/block/blk-flush.c > > +++ b/block/blk-flush.c > > @@ -236,12 +236,10 @@ static void flush_end_io(struct request *flush_rq, blk_status_t error) > > error = fq->rq_status; > > hctx = flush_rq->mq_hctx; > > - if (!q->elevator) { > > - blk_mq_tag_set_rq(hctx, flush_rq->tag, fq->orig_rq); > > + if (!q->elevator) > > flush_rq->tag = -1; > > - } else { > > + else > > flush_rq->internal_tag = -1; > > - } > > running = &fq->flush_queue[fq->flush_running_idx]; > > BUG_ON(fq->flush_pending_idx == fq->flush_running_idx); > > @@ -315,13 +313,10 @@ static void blk_kick_flush(struct request_queue *q, struct blk_flush_queue *fq, > > flush_rq->mq_ctx = first_rq->mq_ctx; > > flush_rq->mq_hctx = first_rq->mq_hctx; > > - if (!q->elevator) { > > - fq->orig_rq = first_rq; > > + if (!q->elevator) > > flush_rq->tag = first_rq->tag; > > - blk_mq_tag_set_rq(flush_rq->mq_hctx, first_rq->tag, flush_rq); > > - } else { > > + else > > flush_rq->internal_tag = first_rq->internal_tag; > > - } > > flush_rq->cmd_flags = REQ_OP_FLUSH | REQ_PREFLUSH; > > flush_rq->cmd_flags |= (flags & REQ_DRV) | (flags & REQ_FAILFAST_MASK); > > diff --git a/block/blk-mq-tag.h b/block/blk-mq-tag.h > > index 3945c7f5b944..b1acac518c4e 100644 > > --- a/block/blk-mq-tag.h > > +++ b/block/blk-mq-tag.h > > @@ -101,18 +101,6 @@ static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, > > return atomic_read(&hctx->nr_active) < depth; > > } > > -/* > > - * This helper should only be used for flush request to share tag > > - * with the request cloned from, and both the two requests can't be > > - * in flight at the same time. The caller has to make sure the tag > > - * can't be freed. > > - */ > > -static inline void blk_mq_tag_set_rq(struct blk_mq_hw_ctx *hctx, > > - unsigned int tag, struct request *rq) > > -{ > > - hctx->tags->rqs[tag] = rq; > > -} > > - > > static inline bool blk_mq_tag_is_reserved(struct blk_mq_tags *tags, > > unsigned int tag) > > { > > diff --git a/block/blk-mq.c b/block/blk-mq.c > > index cabeeeb3d56c..44b101757d33 100644 > > --- a/block/blk-mq.c > > +++ b/block/blk-mq.c > > @@ -277,26 +277,20 @@ 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 = BLK_MQ_NO_TAG; > > rq->internal_tag = tag; > > } else { > > - if (data->hctx->flags & BLK_MQ_F_TAG_SHARED) { > > - rq_flags = RQF_MQ_INFLIGHT; > > - atomic_inc(&data->hctx->nr_active); > > - } > > rq->tag = tag; > > rq->internal_tag = BLK_MQ_NO_TAG; > > - data->hctx->tags->rqs[rq->tag] = rq; > > } > > /* csd/requeue_work/fifo_time is initialized before use */ > > rq->q = data->q; > > rq->mq_ctx = data->ctx; > > rq->mq_hctx = data->hctx; > > - rq->rq_flags = rq_flags; > > + rq->rq_flags = 0; > > rq->cmd_flags = data->cmd_flags; > > if (data->flags & BLK_MQ_REQ_PREEMPT) > > rq->rq_flags |= RQF_PREEMPT; > > @@ -380,8 +374,6 @@ static struct request *__blk_mq_alloc_request(struct blk_mq_alloc_data *data) > > retry: > > data->ctx = blk_mq_get_ctx(q); > > data->hctx = blk_mq_map_queue(q, data->cmd_flags, data->ctx); > > - if (!(data->flags & BLK_MQ_REQ_INTERNAL)) > > - blk_mq_tag_busy(data->hctx); > > /* > > * Waiting allocations only fail because of an inactive hctx. In that > > @@ -478,8 +470,6 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q, > > if (q->elevator) > > data.flags |= BLK_MQ_REQ_INTERNAL; > > - else > > - blk_mq_tag_busy(data.hctx); > > ret = -EWOULDBLOCK; > > tag = blk_mq_get_tag(&data); > > @@ -1131,7 +1121,6 @@ static bool __blk_mq_get_driver_tag(struct request *rq) > > { > > struct sbitmap_queue *bt = &rq->mq_hctx->tags->bitmap_tags; > > unsigned int tag_offset = rq->mq_hctx->tags->nr_reserved_tags; > > - bool shared = blk_mq_tag_busy(rq->mq_hctx); > > int tag; > > if (blk_mq_tag_is_reserved(rq->mq_hctx->sched_tags, rq->internal_tag)) { > > @@ -1146,19 +1135,23 @@ static bool __blk_mq_get_driver_tag(struct request *rq) > > return false; > > rq->tag = tag + tag_offset; > > - if (shared) { > > - rq->rq_flags |= RQF_MQ_INFLIGHT; > > - atomic_inc(&rq->mq_hctx->nr_active); > > - } > > - rq->mq_hctx->tags->rqs[rq->tag] = rq; > > return true; > > } > > static bool blk_mq_get_driver_tag(struct request *rq) > > { > > - if (rq->tag != BLK_MQ_NO_TAG) > > - return true; > > - return __blk_mq_get_driver_tag(rq); > > + struct blk_mq_hw_ctx *hctx = rq->mq_hctx; > > + bool shared = blk_mq_tag_busy(rq->mq_hctx); > > + > > + if (rq->tag == BLK_MQ_NO_TAG && !__blk_mq_get_driver_tag(rq)) > > + return false; > > + > > + if (shared) { > > + rq->rq_flags |= RQF_MQ_INFLIGHT; > > + atomic_inc(&hctx->nr_active); > > + } > > + hctx->tags->rqs[rq->tag] = rq; > > + return true; > > } > > static int blk_mq_dispatch_wake(wait_queue_entry_t *wait, unsigned mode, > > diff --git a/block/blk.h b/block/blk.h > > index 3a120a070dac..459790f9783d 100644 > > --- a/block/blk.h > > +++ b/block/blk.h > > @@ -25,11 +25,6 @@ struct blk_flush_queue { > > struct list_head flush_data_in_flight; > > struct request *flush_rq; > > - /* > > - * flush_rq shares tag with this rq, both can't be active > > - * at the same time > > - */ > > - struct request *orig_rq; > > struct lock_class_key key; > > spinlock_t mq_flush_lock; > > }; > > > Can you give some more explanation why it's safe to move blk_mq_tag_busy() > into blk_mq_get_driver_tag(), seeing that it was called before > blk_mq_get_tag() initially? In theory, it should be done before blk_mq_get_tag() in case of none because hctx_may_queue() will use this info for deciding if one driver tag can be allocated for this lun/ns for the sake of fairness. However, blk_mq_tag_busy() is just one shot thing, and very short time of unfairness shouldn't be a big deal. Looks you guys care this change, I will avoid this kind of change in V2. Thanks, Ming
diff --git a/block/blk-flush.c b/block/blk-flush.c index 21108a550fbf..3b0c5cfe922a 100644 --- a/block/blk-flush.c +++ b/block/blk-flush.c @@ -236,12 +236,10 @@ static void flush_end_io(struct request *flush_rq, blk_status_t error) error = fq->rq_status; hctx = flush_rq->mq_hctx; - if (!q->elevator) { - blk_mq_tag_set_rq(hctx, flush_rq->tag, fq->orig_rq); + if (!q->elevator) flush_rq->tag = -1; - } else { + else flush_rq->internal_tag = -1; - } running = &fq->flush_queue[fq->flush_running_idx]; BUG_ON(fq->flush_pending_idx == fq->flush_running_idx); @@ -315,13 +313,10 @@ static void blk_kick_flush(struct request_queue *q, struct blk_flush_queue *fq, flush_rq->mq_ctx = first_rq->mq_ctx; flush_rq->mq_hctx = first_rq->mq_hctx; - if (!q->elevator) { - fq->orig_rq = first_rq; + if (!q->elevator) flush_rq->tag = first_rq->tag; - blk_mq_tag_set_rq(flush_rq->mq_hctx, first_rq->tag, flush_rq); - } else { + else flush_rq->internal_tag = first_rq->internal_tag; - } flush_rq->cmd_flags = REQ_OP_FLUSH | REQ_PREFLUSH; flush_rq->cmd_flags |= (flags & REQ_DRV) | (flags & REQ_FAILFAST_MASK); diff --git a/block/blk-mq-tag.h b/block/blk-mq-tag.h index 3945c7f5b944..b1acac518c4e 100644 --- a/block/blk-mq-tag.h +++ b/block/blk-mq-tag.h @@ -101,18 +101,6 @@ static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, return atomic_read(&hctx->nr_active) < depth; } -/* - * This helper should only be used for flush request to share tag - * with the request cloned from, and both the two requests can't be - * in flight at the same time. The caller has to make sure the tag - * can't be freed. - */ -static inline void blk_mq_tag_set_rq(struct blk_mq_hw_ctx *hctx, - unsigned int tag, struct request *rq) -{ - hctx->tags->rqs[tag] = rq; -} - static inline bool blk_mq_tag_is_reserved(struct blk_mq_tags *tags, unsigned int tag) { diff --git a/block/blk-mq.c b/block/blk-mq.c index cabeeeb3d56c..44b101757d33 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -277,26 +277,20 @@ 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 = BLK_MQ_NO_TAG; rq->internal_tag = tag; } else { - if (data->hctx->flags & BLK_MQ_F_TAG_SHARED) { - rq_flags = RQF_MQ_INFLIGHT; - atomic_inc(&data->hctx->nr_active); - } rq->tag = tag; rq->internal_tag = BLK_MQ_NO_TAG; - data->hctx->tags->rqs[rq->tag] = rq; } /* csd/requeue_work/fifo_time is initialized before use */ rq->q = data->q; rq->mq_ctx = data->ctx; rq->mq_hctx = data->hctx; - rq->rq_flags = rq_flags; + rq->rq_flags = 0; rq->cmd_flags = data->cmd_flags; if (data->flags & BLK_MQ_REQ_PREEMPT) rq->rq_flags |= RQF_PREEMPT; @@ -380,8 +374,6 @@ static struct request *__blk_mq_alloc_request(struct blk_mq_alloc_data *data) retry: data->ctx = blk_mq_get_ctx(q); data->hctx = blk_mq_map_queue(q, data->cmd_flags, data->ctx); - if (!(data->flags & BLK_MQ_REQ_INTERNAL)) - blk_mq_tag_busy(data->hctx); /* * Waiting allocations only fail because of an inactive hctx. In that @@ -478,8 +470,6 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q, if (q->elevator) data.flags |= BLK_MQ_REQ_INTERNAL; - else - blk_mq_tag_busy(data.hctx); ret = -EWOULDBLOCK; tag = blk_mq_get_tag(&data); @@ -1131,7 +1121,6 @@ static bool __blk_mq_get_driver_tag(struct request *rq) { struct sbitmap_queue *bt = &rq->mq_hctx->tags->bitmap_tags; unsigned int tag_offset = rq->mq_hctx->tags->nr_reserved_tags; - bool shared = blk_mq_tag_busy(rq->mq_hctx); int tag; if (blk_mq_tag_is_reserved(rq->mq_hctx->sched_tags, rq->internal_tag)) { @@ -1146,19 +1135,23 @@ static bool __blk_mq_get_driver_tag(struct request *rq) return false; rq->tag = tag + tag_offset; - if (shared) { - rq->rq_flags |= RQF_MQ_INFLIGHT; - atomic_inc(&rq->mq_hctx->nr_active); - } - rq->mq_hctx->tags->rqs[rq->tag] = rq; return true; } static bool blk_mq_get_driver_tag(struct request *rq) { - if (rq->tag != BLK_MQ_NO_TAG) - return true; - return __blk_mq_get_driver_tag(rq); + struct blk_mq_hw_ctx *hctx = rq->mq_hctx; + bool shared = blk_mq_tag_busy(rq->mq_hctx); + + if (rq->tag == BLK_MQ_NO_TAG && !__blk_mq_get_driver_tag(rq)) + return false; + + if (shared) { + rq->rq_flags |= RQF_MQ_INFLIGHT; + atomic_inc(&hctx->nr_active); + } + hctx->tags->rqs[rq->tag] = rq; + return true; } static int blk_mq_dispatch_wake(wait_queue_entry_t *wait, unsigned mode, diff --git a/block/blk.h b/block/blk.h index 3a120a070dac..459790f9783d 100644 --- a/block/blk.h +++ b/block/blk.h @@ -25,11 +25,6 @@ struct blk_flush_queue { struct list_head flush_data_in_flight; struct request *flush_rq; - /* - * flush_rq shares tag with this rq, both can't be active - * at the same time - */ - struct request *orig_rq; struct lock_class_key key; spinlock_t mq_flush_lock; };
Move blk_mq_tag_busy(), .nr_active update and request assignment into blk_mq_get_driver_tag(), all are good to do during getting driver tag. Meantime blk-flush related code is simplified and flush request needn't to update the request table manually any more. Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Ming Lei <ming.lei@redhat.com> --- block/blk-flush.c | 13 ++++--------- block/blk-mq-tag.h | 12 ------------ block/blk-mq.c | 33 +++++++++++++-------------------- block/blk.h | 5 ----- 4 files changed, 17 insertions(+), 46 deletions(-)