All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH 1/2] block: remove blk_needs_flush_plug
@ 2022-01-27  7:05 Christoph Hellwig
  2022-01-27  7:05 ` [PATCH 2/2] block: check that there is a plug in blk_flush_plug Christoph Hellwig
  2022-01-27 17:19 ` [PATCH 1/2] block: remove blk_needs_flush_plug Jens Axboe
  0 siblings, 2 replies; 4+ messages in thread
From: Christoph Hellwig @ 2022-01-27  7:05 UTC (permalink / raw)
  To: axboe; +Cc: linux-block

blk_needs_flush_plug fails to account for the cb_list, which needs
flushing as well.  Remove it and just check if there is a plug instead
of poking into the internals of the plug structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/fs-writeback.c      |  2 +-
 include/linux/blkdev.h | 13 -------------
 kernel/exit.c          |  2 +-
 kernel/sched/core.c    |  2 +-
 4 files changed, 3 insertions(+), 16 deletions(-)

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index f8d7fe6db989e..f4ce38f6fc31c 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -2301,7 +2301,7 @@ void wakeup_flusher_threads(enum wb_reason reason)
 	/*
 	 * If we are expecting writeback progress we must submit plugged IO.
 	 */
-	if (blk_needs_flush_plug(current))
+	if (current->plug)
 		blk_flush_plug(current->plug, true);
 
 	rcu_read_lock();
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 85c38c3a89c35..95176802ccc92 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1055,14 +1055,6 @@ extern void blk_finish_plug(struct blk_plug *);
 
 void blk_flush_plug(struct blk_plug *plug, bool from_schedule);
 
-static inline bool blk_needs_flush_plug(struct task_struct *tsk)
-{
-	struct blk_plug *plug = tsk->plug;
-
-	return plug &&
-		 (plug->mq_list || !list_empty(&plug->cb_list));
-}
-
 int blkdev_issue_flush(struct block_device *bdev);
 long nr_blockdev_pages(void);
 #else /* CONFIG_BLOCK */
@@ -1086,11 +1078,6 @@ static inline void blk_flush_plug(struct blk_plug *plug, bool async)
 {
 }
 
-static inline bool blk_needs_flush_plug(struct task_struct *tsk)
-{
-	return false;
-}
-
 static inline int blkdev_issue_flush(struct block_device *bdev)
 {
 	return 0;
diff --git a/kernel/exit.c b/kernel/exit.c
index b00a25bb4ab93..11fc6c9df9f28 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -735,7 +735,7 @@ void __noreturn do_exit(long code)
 	struct task_struct *tsk = current;
 	int group_dead;
 
-	WARN_ON(blk_needs_flush_plug(tsk));
+	WARN_ON(tsk->plug);
 
 	/*
 	 * If do_dead is called because this processes oopsed, it's possible
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 2e4ae00e52d14..ccaa17e5a8306 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -6345,7 +6345,7 @@ static inline void sched_submit_work(struct task_struct *tsk)
 	 * If we are going to sleep and we have plugged IO queued,
 	 * make sure to submit it to avoid deadlocks.
 	 */
-	if (blk_needs_flush_plug(tsk))
+	if (tsk->plug)
 		blk_flush_plug(tsk->plug, true);
 }
 
-- 
2.30.2


^ permalink raw reply related	[flat|nested] 4+ messages in thread
* [PATCH 2/2] block: check that there is a plug in blk_flush_plug
  2022-01-27  7:05 [PATCH 1/2] block: remove blk_needs_flush_plug Christoph Hellwig
@ 2022-01-27  7:05 ` Christoph Hellwig
  2022-01-27  7:47   ` Chaitanya Kulkarni
  2022-01-27 17:19 ` [PATCH 1/2] block: remove blk_needs_flush_plug Jens Axboe
  1 sibling, 1 reply; 4+ messages in thread
From: Christoph Hellwig @ 2022-01-27  7:05 UTC (permalink / raw)
  To: axboe; +Cc: linux-block

Rename blk_flush_plug to __blk_flush_plug and add a wrapper that includes
the NULL check instead of open coding that check everywhere.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 block/blk-core.c       | 7 +++----
 fs/fs-writeback.c      | 6 ++----
 include/linux/blkdev.h | 7 ++++++-
 kernel/sched/core.c    | 7 ++-----
 4 files changed, 13 insertions(+), 14 deletions(-)

diff --git a/block/blk-core.c b/block/blk-core.c
index 97f8bc8d3a791..f5f0d45841a47 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -991,8 +991,7 @@ int bio_poll(struct bio *bio, struct io_comp_batch *iob, unsigned int flags)
 	    !test_bit(QUEUE_FLAG_POLL, &q->queue_flags))
 		return 0;
 
-	if (current->plug)
-		blk_flush_plug(current->plug, false);
+	blk_flush_plug(current->plug, false);
 
 	if (blk_queue_enter(q, BLK_MQ_REQ_NOWAIT))
 		return 0;
@@ -1261,7 +1260,7 @@ struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug, void *data,
 }
 EXPORT_SYMBOL(blk_check_plugged);
 
-void blk_flush_plug(struct blk_plug *plug, bool from_schedule)
+void __blk_flush_plug(struct blk_plug *plug, bool from_schedule)
 {
 	if (!list_empty(&plug->cb_list))
 		flush_plug_callbacks(plug, from_schedule);
@@ -1290,7 +1289,7 @@ void blk_flush_plug(struct blk_plug *plug, bool from_schedule)
 void blk_finish_plug(struct blk_plug *plug)
 {
 	if (plug == current->plug) {
-		blk_flush_plug(plug, false);
+		__blk_flush_plug(plug, false);
 		current->plug = NULL;
 	}
 }
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index f4ce38f6fc31c..33d54c9fbefc0 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -1903,8 +1903,7 @@ static long writeback_sb_inodes(struct super_block *sb,
 			 * unplug, so get our IOs out the door before we
 			 * give up the CPU.
 			 */
-			if (current->plug)
-				blk_flush_plug(current->plug, false);
+			blk_flush_plug(current->plug, false);
 			cond_resched();
 		}
 
@@ -2301,8 +2300,7 @@ void wakeup_flusher_threads(enum wb_reason reason)
 	/*
 	 * If we are expecting writeback progress we must submit plugged IO.
 	 */
-	if (current->plug)
-		blk_flush_plug(current->plug, true);
+	blk_flush_plug(current->plug, true);
 
 	rcu_read_lock();
 	list_for_each_entry_rcu(bdi, &bdi_list, bdi_list)
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 95176802ccc92..3020f3c3683df 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1053,7 +1053,12 @@ extern void blk_start_plug(struct blk_plug *);
 extern void blk_start_plug_nr_ios(struct blk_plug *, unsigned short);
 extern void blk_finish_plug(struct blk_plug *);
 
-void blk_flush_plug(struct blk_plug *plug, bool from_schedule);
+void __blk_flush_plug(struct blk_plug *plug, bool from_schedule);
+static inline void blk_flush_plug(struct blk_plug *plug, bool async)
+{
+	if (plug)
+		__blk_flush_plug(plug, async);
+}
 
 int blkdev_issue_flush(struct block_device *bdev);
 long nr_blockdev_pages(void);
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index ccaa17e5a8306..cc3b665bd3582 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -6345,8 +6345,7 @@ static inline void sched_submit_work(struct task_struct *tsk)
 	 * If we are going to sleep and we have plugged IO queued,
 	 * make sure to submit it to avoid deadlocks.
 	 */
-	if (tsk->plug)
-		blk_flush_plug(tsk->plug, true);
+	blk_flush_plug(tsk->plug, true);
 }
 
 static void sched_update_worker(struct task_struct *tsk)
@@ -8378,9 +8377,7 @@ int io_schedule_prepare(void)
 	int old_iowait = current->in_iowait;
 
 	current->in_iowait = 1;
-	if (current->plug)
-		blk_flush_plug(current->plug, true);
-
+	blk_flush_plug(current->plug, true);
 	return old_iowait;
 }
 
-- 
2.30.2


^ permalink raw reply related	[flat|nested] 4+ messages in thread
* Re: [PATCH 2/2] block: check that there is a plug in blk_flush_plug
  2022-01-27  7:05 ` [PATCH 2/2] block: check that there is a plug in blk_flush_plug Christoph Hellwig
@ 2022-01-27  7:47   ` Chaitanya Kulkarni
  0 siblings, 0 replies; 4+ messages in thread
From: Chaitanya Kulkarni @ 2022-01-27  7:47 UTC (permalink / raw)
  To: Christoph Hellwig, axboe; +Cc: linux-block

On 1/26/22 11:05 PM, Christoph Hellwig wrote:
> Rename blk_flush_plug to __blk_flush_plug and add a wrapper that includes
> the NULL check instead of open coding that check everywhere.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>


Looks good.

Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>




^ permalink raw reply	[flat|nested] 4+ messages in thread
* Re: [PATCH 1/2] block: remove blk_needs_flush_plug
  2022-01-27  7:05 [PATCH 1/2] block: remove blk_needs_flush_plug Christoph Hellwig
  2022-01-27  7:05 ` [PATCH 2/2] block: check that there is a plug in blk_flush_plug Christoph Hellwig
@ 2022-01-27 17:19 ` Jens Axboe
  1 sibling, 0 replies; 4+ messages in thread
From: Jens Axboe @ 2022-01-27 17:19 UTC (permalink / raw)
  To: Christoph Hellwig; +Cc: linux-block

On Thu, 27 Jan 2022 08:05:48 +0100, Christoph Hellwig wrote:
> blk_needs_flush_plug fails to account for the cb_list, which needs
> flushing as well.  Remove it and just check if there is a plug instead
> of poking into the internals of the plug structure.
> 
> 

Applied, thanks!

[1/2] block: remove blk_needs_flush_plug
      commit: 1642097f8e40bf81c9c5976879a561eb098fc6d8
[2/2] block: check that there is a plug in blk_flush_plug
      commit: 1741f0be918539f186e8262d4bd020629c60b400

Best regards,
-- 
Jens Axboe



^ permalink raw reply	[flat|nested] 4+ messages in thread
end of thread, other threads:[~2022-01-27 17:19 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-01-27  7:05 [PATCH 1/2] block: remove blk_needs_flush_plug Christoph Hellwig
2022-01-27  7:05 ` [PATCH 2/2] block: check that there is a plug in blk_flush_plug Christoph Hellwig
2022-01-27  7:47   ` Chaitanya Kulkarni
2022-01-27 17:19 ` [PATCH 1/2] block: remove blk_needs_flush_plug Jens Axboe

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.