diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-core.c | 19 | ||||
| -rw-r--r-- | block/elevator.c | 7 |
2 files changed, 20 insertions, 6 deletions
diff --git a/block/blk-core.c b/block/blk-core.c index 2d053b584410..91532f2d2fa7 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -325,6 +325,9 @@ EXPORT_SYMBOL(blk_unplug); static void blk_invoke_request_fn(struct request_queue *q) { + if (unlikely(blk_queue_stopped(q))) + return; + /* * one level of recursion is ok and is much faster than kicking * the unplug handling @@ -399,8 +402,13 @@ void blk_sync_queue(struct request_queue *q) EXPORT_SYMBOL(blk_sync_queue); /** - * blk_run_queue - run a single device queue + * __blk_run_queue - run a single device queue * @q: The queue to run + * + * Description: + * See @blk_run_queue. This variant must be called with the queue lock + * held and interrupts disabled. + * */ void __blk_run_queue(struct request_queue *q) { @@ -418,6 +426,12 @@ EXPORT_SYMBOL(__blk_run_queue); /** * blk_run_queue - run a single device queue * @q: The queue to run + * + * Description: + * Invoke request handling on this queue, if it has pending work to do. + * May be used to restart queueing when a request has completed. Also + * See @blk_start_queueing. + * */ void blk_run_queue(struct request_queue *q) { @@ -884,7 +898,8 @@ EXPORT_SYMBOL(blk_get_request); * * This is basically a helper to remove the need to know whether a queue * is plugged or not if someone just wants to initiate dispatch of requests - * for this queue. + * for this queue. Should be used to start queueing on a device outside + * of ->request_fn() context. Also see @blk_run_queue. * * The queue lock must be held with interrupts disabled. */ diff --git a/block/elevator.c b/block/elevator.c index 9482ffa1aae6..59173a69ebdf 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -612,7 +612,7 @@ void elv_insert(struct request_queue *q, struct request *rq, int where) * processing. */ blk_remove_plug(q); - q->request_fn(q); + blk_start_queueing(q); break; case ELEVATOR_INSERT_SORT: @@ -950,7 +950,7 @@ void elv_completed_request(struct request_queue *q, struct request *rq) blk_ordered_cur_seq(q) == QUEUE_ORDSEQ_DRAIN && blk_ordered_req_seq(first_rq) > QUEUE_ORDSEQ_DRAIN) { blk_ordered_complete_seq(q, QUEUE_ORDSEQ_DRAIN, 0); - q->request_fn(q); + blk_start_queueing(q); } } } @@ -1109,8 +1109,7 @@ static int elevator_switch(struct request_queue *q, struct elevator_type *new_e) elv_drain_elevator(q); while (q->rq.elvpriv) { - blk_remove_plug(q); - q->request_fn(q); + blk_start_queueing(q); spin_unlock_irq(q->queue_lock); msleep(10); spin_lock_irq(q->queue_lock); |