diff options
Diffstat (limited to 'block/blk-mq-tag.h')
| -rw-r--r-- | block/blk-mq-tag.h | 41 |
1 files changed, 26 insertions, 15 deletions
diff --git a/block/blk-mq-tag.h b/block/blk-mq-tag.h index 2e4ef51cdb32..b1acac518c4e 100644 --- a/block/blk-mq-tag.h +++ b/block/blk-mq-tag.h @@ -51,14 +51,6 @@ enum { BLK_MQ_TAG_MAX = BLK_MQ_NO_TAG - 1, }; -bool __blk_mq_get_driver_tag(struct request *rq); -static inline 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); -} - extern bool __blk_mq_tag_busy(struct blk_mq_hw_ctx *); extern void __blk_mq_tag_idle(struct blk_mq_hw_ctx *); @@ -79,15 +71,34 @@ static inline void blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx) } /* - * 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. + * For shared tag users, we track the number of currently active users + * and attempt to provide a fair share of the tag depth for each of them. */ -static inline void blk_mq_tag_set_rq(struct blk_mq_hw_ctx *hctx, - unsigned int tag, struct request *rq) +static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, + struct sbitmap_queue *bt) { - hctx->tags->rqs[tag] = rq; + unsigned int depth, users; + + if (!hctx || !(hctx->flags & BLK_MQ_F_TAG_SHARED)) + return true; + if (!test_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state)) + return true; + + /* + * Don't try dividing an ant + */ + if (bt->sb.depth == 1) + return true; + + users = atomic_read(&hctx->tags->active_queues); + if (!users) + return true; + + /* + * Allow at least some tags + */ + depth = max((bt->sb.depth + users - 1) / users, 4U); + return atomic_read(&hctx->nr_active) < depth; } static inline bool blk_mq_tag_is_reserved(struct blk_mq_tags *tags, |