diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-mq-sched.c | 58 | ||||
| -rw-r--r-- | block/blk-mq-sched.h | 9 | ||||
| -rw-r--r-- | block/blk-mq.c | 16 | ||||
| -rw-r--r-- | block/blk-sysfs.c | 34 |
4 files changed, 81 insertions, 36 deletions
diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index 191bf82d185e..7f0dc48ffb40 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -50,6 +50,45 @@ void blk_mq_sched_assign_ioc(struct request *rq, struct bio *bio) rq->elv.icq = icq; } +/* + * Mark a hardware queue as needing a restart. For shared queues, maintain + * a count of how many hardware queues are marked for restart. + */ +static void blk_mq_sched_mark_restart_hctx(struct blk_mq_hw_ctx *hctx) +{ + if (test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state)) + return; + + if (hctx->flags & BLK_MQ_F_TAG_SHARED) { + struct request_queue *q = hctx->queue; + + if (!test_and_set_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state)) + atomic_inc(&q->shared_hctx_restart); + } else + set_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state); +} + +static bool blk_mq_sched_restart_hctx(struct blk_mq_hw_ctx *hctx) +{ + if (!test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state)) + return false; + + if (hctx->flags & BLK_MQ_F_TAG_SHARED) { + struct request_queue *q = hctx->queue; + + if (test_and_clear_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state)) + atomic_dec(&q->shared_hctx_restart); + } else + clear_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state); + + if (blk_mq_hctx_has_pending(hctx)) { + blk_mq_run_hw_queue(hctx, true); + return true; + } + + return false; +} + void blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx) { struct request_queue *q = hctx->queue; @@ -238,18 +277,6 @@ static bool blk_mq_sched_bypass_insert(struct blk_mq_hw_ctx *hctx, return true; } -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)) { - blk_mq_run_hw_queue(hctx, true); - return true; - } - } - return false; -} - /** * list_for_each_entry_rcu_rr - iterate in a round-robin fashion over rcu list * @pos: loop cursor. @@ -281,6 +308,13 @@ void blk_mq_sched_restart(struct blk_mq_hw_ctx *const hctx) unsigned int i, j; if (set->flags & BLK_MQ_F_TAG_SHARED) { + /* + * If this is 0, then we know that no hardware queues + * have RESTART marked. We're done. + */ + if (!atomic_read(&queue->shared_hctx_restart)) + return; + rcu_read_lock(); list_for_each_entry_rcu_rr(q, queue, &set->tag_list, tag_set_list) { diff --git a/block/blk-mq-sched.h b/block/blk-mq-sched.h index e117edd039b1..9267d0b7c197 100644 --- a/block/blk-mq-sched.h +++ b/block/blk-mq-sched.h @@ -91,15 +91,6 @@ static inline bool blk_mq_sched_has_work(struct blk_mq_hw_ctx *hctx) return false; } -/* - * Mark a hardware queue as needing a restart. - */ -static inline void blk_mq_sched_mark_restart_hctx(struct blk_mq_hw_ctx *hctx) -{ - if (!test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state)) - set_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state); -} - 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 c56b64ae1741..05dfa3f270ae 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2112,20 +2112,30 @@ static void blk_mq_map_swqueue(struct request_queue *q, } } +/* + * Caller needs to ensure that we're either frozen/quiesced, or that + * the queue isn't live yet. + */ static void queue_set_hctx_shared(struct request_queue *q, bool shared) { struct blk_mq_hw_ctx *hctx; int i; queue_for_each_hw_ctx(q, hctx, i) { - if (shared) + if (shared) { + if (test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state)) + atomic_inc(&q->shared_hctx_restart); hctx->flags |= BLK_MQ_F_TAG_SHARED; - else + } else { + if (test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state)) + atomic_dec(&q->shared_hctx_restart); hctx->flags &= ~BLK_MQ_F_TAG_SHARED; + } } } -static void blk_mq_update_tag_set_depth(struct blk_mq_tag_set *set, bool shared) +static void blk_mq_update_tag_set_depth(struct blk_mq_tag_set *set, + bool shared) { struct request_queue *q; diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 283da7fbe034..27aceab1cc31 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -777,24 +777,25 @@ static void blk_free_queue_rcu(struct rcu_head *rcu_head) } /** - * blk_release_queue: - release a &struct request_queue when it is no longer needed - * @kobj: the kobj belonging to the request queue to be released + * __blk_release_queue - release a request queue when it is no longer needed + * @work: pointer to the release_work member of the request queue to be released * * Description: - * blk_release_queue is the pair to blk_init_queue() or - * blk_queue_make_request(). It should be called when a request queue is - * being released; typically when a block device is being de-registered. - * Currently, its primary task it to free all the &struct request - * structures that were allocated to the queue and the queue itself. + * blk_release_queue is the counterpart of blk_init_queue(). It should be + * called when a request queue is being released; typically when a block + * device is being de-registered. Its primary task it to free the queue + * itself. * - * Note: + * Notes: * The low level driver must have finished any outstanding requests first * via blk_cleanup_queue(). - **/ -static void blk_release_queue(struct kobject *kobj) + * + * Although blk_release_queue() may be called with preemption disabled, + * __blk_release_queue() may sleep. + */ +static void __blk_release_queue(struct work_struct *work) { - struct request_queue *q = - container_of(kobj, struct request_queue, kobj); + struct request_queue *q = container_of(work, typeof(*q), release_work); if (test_bit(QUEUE_FLAG_POLL_STATS, &q->queue_flags)) blk_stat_remove_callback(q, q->poll_cb); @@ -834,6 +835,15 @@ static void blk_release_queue(struct kobject *kobj) call_rcu(&q->rcu_head, blk_free_queue_rcu); } +static void blk_release_queue(struct kobject *kobj) +{ + struct request_queue *q = + container_of(kobj, struct request_queue, kobj); + + INIT_WORK(&q->release_work, __blk_release_queue); + schedule_work(&q->release_work); +} + static const struct sysfs_ops queue_sysfs_ops = { .show = queue_attr_show, .store = queue_attr_store, |