From efd4b81abbe1ac753717f2f10cd3dab8bed6c103 Mon Sep 17 00:00:00 2001
From: Omar Sandoval <osandov@fb.com>
Date: Thu, 16 Mar 2017 09:46:14 -0600
Subject: [PATCH] blk-stat: fix blk_stat_sum() if all samples are batched
We need to flush the batch _before_ we check the number of samples,
otherwise we'll miss all of the batched samples.
Fixes: cf43e6b ("block: add scalable completion tracking of requests")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
---
block/blk-stat.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/block/blk-stat.c b/block/blk-stat.c
index 9b43efb8933fb..186fcb981e9b1 100644
--- a/block/blk-stat.c
+++ b/block/blk-stat.c
@@ -30,11 +30,11 @@ static void blk_stat_flush_batch(struct blk_rq_stat *stat)
static void blk_stat_sum(struct blk_rq_stat *dst, struct blk_rq_stat *src)
{
+ blk_stat_flush_batch(src);
+
if (!src->nr_samples)
return;
- blk_stat_flush_batch(src);
-
dst->min = min(dst->min, src->min);
dst->max = max(dst->max, src->max);
--
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