Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Wed, 10 Oct 2018 10:26:23 -0700
Message-Id: <20181010172623.57033-1-khazhy@google.com>
Mime-Version: 1.0
Subject: [PATCH] fs/fat: add cond_resched to fat_count_free_clusters
From:   Khazhismel Kumykov <khazhy@google.com>
To:     hirofumi@mail.parknet.co.jp
Cc:     linux-kernel@vger.kernel.org,
        Khazhismel Kumykov <khazhy@google.com>
Content-Type: text/plain; charset="UTF-8"
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On non-preempt kernels this loop can take a long time (more than 50
ticks) processing through entries.

Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
---
 fs/fat/fatent.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/fs/fat/fatent.c b/fs/fat/fatent.c
index defc2168de91..f58c0cacc531 100644
--- a/fs/fat/fatent.c
+++ b/fs/fat/fatent.c
@@ -682,6 +682,7 @@ int fat_count_free_clusters(struct super_block *sb)
 			if (ops->ent_get(&fatent) == FAT_ENT_FREE)
 				free++;
 		} while (fat_ent_next(sbi, &fatent));
+		cond_resched();
 	}
 	sbi->free_clusters = free;
 	sbi->free_clus_valid = 1;
-- 
2.19.0.605.g01d371f741-goog