diff options
| -rw-r--r-- | block/blk-mq-sched.c | 63 | ||||
| -rw-r--r-- | block/blk-mq-sched.h | 16 | ||||
| -rw-r--r-- | block/blk-mq.c | 2 | ||||
| -rw-r--r-- | include/linux/blkdev.h | 1 |
4 files changed, 55 insertions, 27 deletions
diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index e8c2ed654ef0..c974a1bbf4cb 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -318,25 +318,68 @@ static bool blk_mq_sched_bypass_insert(struct blk_mq_hw_ctx *hctx, return true; } -static void blk_mq_sched_restart_hctx(struct blk_mq_hw_ctx *hctx) +static bool blk_mq_sched_restart_hctx(struct blk_mq_hw_ctx *hctx) { if (test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state)) { clear_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state); - if (blk_mq_hctx_has_pending(hctx)) + if (blk_mq_hctx_has_pending(hctx)) { blk_mq_run_hw_queue(hctx, true); + return true; + } } + return false; } -void blk_mq_sched_restart_queues(struct blk_mq_hw_ctx *hctx) -{ - struct request_queue *q = hctx->queue; - unsigned int i; +/** + * list_for_each_entry_rcu_rr - iterate in a round-robin fashion over rcu list + * @pos: loop cursor. + * @skip: the list element that will not be examined. Iteration starts at + * @skip->next. + * @head: head of the list to examine. This list must have at least one + * element, namely @skip. + * @member: name of the list_head structure within typeof(*pos). + */ +#define list_for_each_entry_rcu_rr(pos, skip, head, member) \ + for ((pos) = (skip); \ + (pos = (pos)->member.next != (head) ? list_entry_rcu( \ + (pos)->member.next, typeof(*pos), member) : \ + list_entry_rcu((pos)->member.next->next, typeof(*pos), member)), \ + (pos) != (skip); ) - if (test_bit(QUEUE_FLAG_RESTART, &q->queue_flags)) { - if (test_and_clear_bit(QUEUE_FLAG_RESTART, &q->queue_flags)) { - queue_for_each_hw_ctx(q, hctx, i) - blk_mq_sched_restart_hctx(hctx); +/* + * Called after a driver tag has been freed to check whether a hctx needs to + * be restarted. Restarts @hctx if its tag set is not shared. Restarts hardware + * queues in a round-robin fashion if the tag set of @hctx is shared with other + * hardware queues. + */ +void blk_mq_sched_restart(struct blk_mq_hw_ctx *const hctx) +{ + struct blk_mq_tags *const tags = hctx->tags; + struct blk_mq_tag_set *const set = hctx->queue->tag_set; + struct request_queue *const queue = hctx->queue, *q; + struct blk_mq_hw_ctx *hctx2; + unsigned int i, j; + + if (set->flags & BLK_MQ_F_TAG_SHARED) { + rcu_read_lock(); + list_for_each_entry_rcu_rr(q, queue, &set->tag_list, + tag_set_list) { + queue_for_each_hw_ctx(q, hctx2, i) + if (hctx2->tags == tags && + blk_mq_sched_restart_hctx(hctx2)) + goto done; + } + j = hctx->queue_num + 1; + for (i = 0; i < queue->nr_hw_queues; i++, j++) { + if (j == queue->nr_hw_queues) + j = 0; + hctx2 = queue->queue_hw_ctx[j]; + if (hctx2->tags == tags && + blk_mq_sched_restart_hctx(hctx2)) + break; } +done: + rcu_read_unlock(); } else { blk_mq_sched_restart_hctx(hctx); } diff --git a/block/blk-mq-sched.h b/block/blk-mq-sched.h index e704956e0862..3a9e6e40558b 100644 --- a/block/blk-mq-sched.h +++ b/block/blk-mq-sched.h @@ -19,7 +19,7 @@ bool blk_mq_sched_try_merge(struct request_queue *q, struct bio *bio, struct request **merged_request); bool __blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio); bool blk_mq_sched_try_insert_merge(struct request_queue *q, struct request *rq); -void blk_mq_sched_restart_queues(struct blk_mq_hw_ctx *hctx); +void blk_mq_sched_restart(struct blk_mq_hw_ctx *hctx); void blk_mq_sched_insert_request(struct request *rq, bool at_head, bool run_queue, bool async, bool can_block); @@ -136,20 +136,6 @@ static inline void blk_mq_sched_mark_restart_hctx(struct blk_mq_hw_ctx *hctx) set_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state); } -/* - * Mark a hardware queue and the request queue it belongs to as needing a - * restart. - */ -static inline void blk_mq_sched_mark_restart_queue(struct blk_mq_hw_ctx *hctx) -{ - struct request_queue *q = hctx->queue; - - if (!test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state)) - set_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state); - if (!test_bit(QUEUE_FLAG_RESTART, &q->queue_flags)) - set_bit(QUEUE_FLAG_RESTART, &q->queue_flags); -} - static inline bool blk_mq_sched_needs_restart(struct blk_mq_hw_ctx *hctx) { return test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state); diff --git a/block/blk-mq.c b/block/blk-mq.c index ad45ae743186..572966f49596 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -348,7 +348,7 @@ void __blk_mq_finish_request(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx, blk_mq_put_tag(hctx, hctx->tags, ctx, rq->tag); if (sched_tag != -1) blk_mq_sched_completed_request(hctx, rq); - blk_mq_sched_restart_queues(hctx); + blk_mq_sched_restart(hctx); blk_queue_exit(q); } diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 5a7da607ca04..7548f332121a 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -610,7 +610,6 @@ struct request_queue { #define QUEUE_FLAG_FLUSH_NQ 25 /* flush not queueuable */ #define QUEUE_FLAG_DAX 26 /* device supports DAX */ #define QUEUE_FLAG_STATS 27 /* track rq completion times */ -#define QUEUE_FLAG_RESTART 28 /* queue needs restart at completion */ #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ (1 << QUEUE_FLAG_STACKABLE) | \ |