From d55a4ae9e1af5fb1657e38284ef46c56e668efdb Mon Sep 17 00:00:00 2001
From: Shile Zhang <shile.zhang@linux.alibaba.com>
Date: Tue, 3 Sep 2019 21:25:43 +0800
Subject: [PATCH] bcache: add cond_resched() in __bch_cache_cmp()

Read /sys/fs/bcache/<uuid>/cacheN/priority_stats can take very long
time with huge cache after long run.

Signed-off-by: Shile Zhang <shile.zhang@linux.alibaba.com>
Tested-by: Heitor Alves de Siqueira <halves@canonical.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 drivers/md/bcache/sysfs.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index 9f0826712845..6b29e34acf7a 100644
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -960,6 +960,7 @@ KTYPE(bch_cache_set_internal);
 
 static int __bch_cache_cmp(const void *l, const void *r)
 {
+	cond_resched();
 	return *((uint16_t *)r) - *((uint16_t *)l);
 }