[PATCH] block: Fix io statistics for cgroup in throttle path

[PATCH] block: Fix io statistics for cgroup in throttle path

[Jinke Han]

From: Jinke Han <hanjinke.666@bytedance.com>

In the current code, io statistics are missing for cgroup when bio
was throttled by blk-throttle. Fix it by moving the unreaching code
to submit_bio_noacct_nocheck.

Fixes: 3f98c753717c ("block: don't check bio in blk_throtl_dispatch_work_fn")
Signed-off-by: Jinke Han <hanjinke.666@bytedance.com>
---
 block/blk-core.c | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/block/blk-core.c b/block/blk-core.c
index 46d12b3344c9..82b5b2c53f1e 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -684,6 +684,18 @@ static void __submit_bio_noacct_mq(struct bio *bio)
 
 void submit_bio_noacct_nocheck(struct bio *bio)
 {
+	blk_cgroup_bio_start(bio);
+	blkcg_bio_issue_init(bio);
+
+	if (!bio_flagged(bio, BIO_TRACE_COMPLETION)) {
+		trace_block_bio_queue(bio);
+		/*
+		 * Now that enqueuing has been traced, we need to trace
+		 * completion as well.
+		 */
+		bio_set_flag(bio, BIO_TRACE_COMPLETION);
+	}
+
 	/*
 	 * We only want one ->submit_bio to be active at a time, else stack
 	 * usage with stacked devices could be a problem.  Use current->bio_list
@@ -792,17 +804,6 @@ void submit_bio_noacct(struct bio *bio)
 
 	if (blk_throtl_bio(bio))
 		return;
-
-	blk_cgroup_bio_start(bio);
-	blkcg_bio_issue_init(bio);
-
-	if (!bio_flagged(bio, BIO_TRACE_COMPLETION)) {
-		trace_block_bio_queue(bio);
-		/* Now that enqueuing has been traced, we need to trace
-		 * completion as well.
-		 */
-		bio_set_flag(bio, BIO_TRACE_COMPLETION);
-	}
 	submit_bio_noacct_nocheck(bio);
 	return;
 
-- 
2.20.1

Re: [PATCH] block: Fix io statistics for cgroup in throttle path

[Christoph Hellwig]

Looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>

Re: [PATCH] block: Fix io statistics for cgroup in throttle path

[Ming Lei]

On Thu, Feb 16, 2023 at 11:22:50AM +0800, Jinke Han wrote:
> From: Jinke Han <hanjinke.666@bytedance.com>
> 
> In the current code, io statistics are missing for cgroup when bio
> was throttled by blk-throttle. Fix it by moving the unreaching code
> to submit_bio_noacct_nocheck.
> 
> Fixes: 3f98c753717c ("block: don't check bio in blk_throtl_dispatch_work_fn")
> Signed-off-by: Jinke Han <hanjinke.666@bytedance.com>

Looks fine,

Reviewed-by: Ming Lei <ming.lei@redhat.com>


Thanks,
Ming

Re: [PATCH] block: Fix io statistics for cgroup in throttle path

[Muchun Song]

> On Feb 16, 2023, at 11:22, Jinke Han <hanjinke.666@bytedance.com> wrote:
> 
> From: Jinke Han <hanjinke.666@bytedance.com>
> 
> In the current code, io statistics are missing for cgroup when bio
> was throttled by blk-throttle. Fix it by moving the unreaching code
> to submit_bio_noacct_nocheck.
> 
> Fixes: 3f98c753717c ("block: don't check bio in blk_throtl_dispatch_work_fn")
> Signed-off-by: Jinke Han <hanjinke.666@bytedance.com>

Acked-by: Muchun Song <songmuchun@bytedance.com>

Thanks.

Re: [PATCH] block: Fix io statistics for cgroup in throttle path

[Jens Axboe]

On Thu, 16 Feb 2023 11:22:50 +0800, Jinke Han wrote:
> In the current code, io statistics are missing for cgroup when bio
> was throttled by blk-throttle. Fix it by moving the unreaching code
> to submit_bio_noacct_nocheck.
> 
> 

Applied, thanks!

[1/1] block: Fix io statistics for cgroup in throttle path
      commit: 0f7c8f0f7934c389b0f9fa1f151e753d8de6348f

Best regards,
-- 
Jens Axboe