Commit 8a83f331 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block 

* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  block: add blk_run_queue_async
  block: blk_delay_queue() should use kblockd workqueue
  md: fix up raid1/raid10 unplugging.
  md: incorporate new plugging into raid5.
  md: provide generic support for handling unplug callbacks.
  md - remove old plugging code.
  md/dm - remove remains of plug_fn callback.
  md: use new plugging interface for RAID IO.
  block: drop queue lock before calling __blk_run_queue() for kblockd punt
  Revert "block: add callback function for unplug notification"
  block: Enhance new plugging support to support general callbacks
parents 5d5b1b9f 24ecfbe2

block/blk-core.c

+65 −18
Original line number Diff line number Diff line
@@ -204,7 +204,7 @@ static void blk_delay_work(struct work_struct *work) 


	q = container_of(work, struct request_queue, delay_work.work);

	spin_lock_irq(q->queue_lock);

	__blk_run_queue(q, false);

	__blk_run_queue(q);

	spin_unlock_irq(q->queue_lock);

}
@@ -220,7 +220,8 @@ static void blk_delay_work(struct work_struct *work) 
 */

void blk_delay_queue(struct request_queue *q, unsigned long msecs)

{

	schedule_delayed_work(&q->delay_work, msecs_to_jiffies(msecs));

	queue_delayed_work(kblockd_workqueue, &q->delay_work,

				msecs_to_jiffies(msecs));

}

EXPORT_SYMBOL(blk_delay_queue);
@@ -238,7 +239,7 @@ void blk_start_queue(struct request_queue *q) 
	WARN_ON(!irqs_disabled());



	queue_flag_clear(QUEUE_FLAG_STOPPED, q);

	__blk_run_queue(q, false);

	__blk_run_queue(q);

}

EXPORT_SYMBOL(blk_start_queue);
@@ -296,9 +297,8 @@ EXPORT_SYMBOL(blk_sync_queue); 
 * 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, bool force_kblockd)

void __blk_run_queue(struct request_queue *q)

{

	if (unlikely(blk_queue_stopped(q)))

		return;
@@ -307,7 +307,7 @@ void __blk_run_queue(struct request_queue *q, bool force_kblockd) 
	 * Only recurse once to avoid overrunning the stack, let the unplug

	 * handling reinvoke the handler shortly if we already got there.

	 */

	if (!force_kblockd && !queue_flag_test_and_set(QUEUE_FLAG_REENTER, q)) {

	if (!queue_flag_test_and_set(QUEUE_FLAG_REENTER, q)) {

		q->request_fn(q);

		queue_flag_clear(QUEUE_FLAG_REENTER, q);

	} else
@@ -315,6 +315,20 @@ void __blk_run_queue(struct request_queue *q, bool force_kblockd) 
}

EXPORT_SYMBOL(__blk_run_queue);



/**

 * blk_run_queue_async - run a single device queue in workqueue context

 * @q:	The queue to run

 *

 * Description:

 *    Tells kblockd to perform the equivalent of @blk_run_queue on behalf

 *    of us.

 */

void blk_run_queue_async(struct request_queue *q)

{

	if (likely(!blk_queue_stopped(q)))

		queue_delayed_work(kblockd_workqueue, &q->delay_work, 0);

}



/**

 * blk_run_queue - run a single device queue

 * @q: The queue to run
@@ -328,7 +342,7 @@ void blk_run_queue(struct request_queue *q) 
	unsigned long flags;



	spin_lock_irqsave(q->queue_lock, flags);

	__blk_run_queue(q, false);

	__blk_run_queue(q);

	spin_unlock_irqrestore(q->queue_lock, flags);

}

EXPORT_SYMBOL(blk_run_queue);
@@ -977,7 +991,7 @@ void blk_insert_request(struct request_queue *q, struct request *rq, 
		blk_queue_end_tag(q, rq);



	add_acct_request(q, rq, where);

	__blk_run_queue(q, false);

	__blk_run_queue(q);

	spin_unlock_irqrestore(q->queue_lock, flags);

}

EXPORT_SYMBOL(blk_insert_request);
@@ -1321,7 +1335,7 @@ get_rq: 
	} else {

		spin_lock_irq(q->queue_lock);

		add_acct_request(q, req, where);

		__blk_run_queue(q, false);

		__blk_run_queue(q);

out_unlock:

		spin_unlock_irq(q->queue_lock);

	}
@@ -2638,6 +2652,7 @@ void blk_start_plug(struct blk_plug *plug) 


	plug->magic = PLUG_MAGIC;

	INIT_LIST_HEAD(&plug->list);

	INIT_LIST_HEAD(&plug->cb_list);

	plug->should_sort = 0;



	/*
@@ -2670,12 +2685,41 @@ static int plug_rq_cmp(void *priv, struct list_head *a, struct list_head *b) 
 */

static void queue_unplugged(struct request_queue *q, unsigned int depth,

			    bool from_schedule)

	__releases(q->queue_lock)

{

	trace_block_unplug(q, depth, !from_schedule);

	__blk_run_queue(q, from_schedule);



	if (q->unplugged_fn)

		q->unplugged_fn(q);

	/*

	 * If we are punting this to kblockd, then we can safely drop

	 * the queue_lock before waking kblockd (which needs to take

	 * this lock).

	 */

	if (from_schedule) {

		spin_unlock(q->queue_lock);

		blk_run_queue_async(q);

	} else {

		__blk_run_queue(q);

		spin_unlock(q->queue_lock);

	}



}



static void flush_plug_callbacks(struct blk_plug *plug)

{

	LIST_HEAD(callbacks);



	if (list_empty(&plug->cb_list))

		return;



	list_splice_init(&plug->cb_list, &callbacks);



	while (!list_empty(&callbacks)) {

		struct blk_plug_cb *cb = list_first_entry(&callbacks,

							  struct blk_plug_cb,

							  list);

		list_del(&cb->list);

		cb->callback(cb);

	}

}



void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule)
@@ -2688,6 +2732,7 @@ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule) 


	BUG_ON(plug->magic != PLUG_MAGIC);



	flush_plug_callbacks(plug);

	if (list_empty(&plug->list))

		return;
@@ -2712,10 +2757,11 @@ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule) 
		BUG_ON(!(rq->cmd_flags & REQ_ON_PLUG));

		BUG_ON(!rq->q);

		if (rq->q != q) {

			if (q) {

			/*

			 * This drops the queue lock

			 */

			if (q)

				queue_unplugged(q, depth, from_schedule);

				spin_unlock(q->queue_lock);

			}

			q = rq->q;

			depth = 0;

			spin_lock(q->queue_lock);
@@ -2733,10 +2779,11 @@ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule) 
		depth++;

	}



	if (q) {

	/*

	 * This drops the queue lock

	 */

	if (q)

		queue_unplugged(q, depth, from_schedule);

		spin_unlock(q->queue_lock);

	}



	local_irq_restore(flags);

}

block/blk-exec.c

+1 −1
Original line number Diff line number Diff line
@@ -55,7 +55,7 @@ void blk_execute_rq_nowait(struct request_queue *q, struct gendisk *bd_disk, 
	WARN_ON(irqs_disabled());

	spin_lock_irq(q->queue_lock);

	__elv_add_request(q, rq, where);

	__blk_run_queue(q, false);

	__blk_run_queue(q);

	/* the queue is stopped so it won't be plugged+unplugged */

	if (rq->cmd_type == REQ_TYPE_PM_RESUME)

		q->request_fn(q);

block/blk-flush.c

+2 −2
Original line number Diff line number Diff line
@@ -218,7 +218,7 @@ static void flush_end_io(struct request *flush_rq, int error) 
	 * request_fn may confuse the driver.  Always use kblockd.

	 */

	if (queued)

		__blk_run_queue(q, true);

		blk_run_queue_async(q);

}



/**
@@ -274,7 +274,7 @@ static void flush_data_end_io(struct request *rq, int error) 
	 * the comment in flush_end_io().

	 */

	if (blk_flush_complete_seq(rq, REQ_FSEQ_DATA, error))

		__blk_run_queue(q, true);

		blk_run_queue_async(q);

}



/**

block/blk-settings.c

+0 −16
Original line number Diff line number Diff line
@@ -790,22 +790,6 @@ void blk_queue_flush(struct request_queue *q, unsigned int flush) 
}

EXPORT_SYMBOL_GPL(blk_queue_flush);



/**

 * blk_queue_unplugged - register a callback for an unplug event

 * @q:		the request queue for the device

 * @fn:		the function to call

 *

 * Some stacked drivers may need to know when IO is dispatched on an

 * unplug event. By registrering a callback here, they will be notified

 * when someone flushes their on-stack queue plug. The function will be

 * called with the queue lock held.

 */

void blk_queue_unplugged(struct request_queue *q, unplugged_fn *fn)

{

	q->unplugged_fn = fn;

}

EXPORT_SYMBOL(blk_queue_unplugged);



static int __init blk_settings_init(void)

{

	blk_max_low_pfn = max_low_pfn - 1;

block/blk.h

+1 −0
Original line number Diff line number Diff line
@@ -22,6 +22,7 @@ void blk_rq_timed_out_timer(unsigned long data); 
void blk_delete_timer(struct request *);

void blk_add_timer(struct request *);

void __generic_unplug_device(struct request_queue *);

void blk_run_queue_async(struct request_queue *q);



/*

 * Internal atomic flags for request handling

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