[PATCH] fs/buffer: adjust the order of might_sleep() in __getblk_gfp()

[gouhao]

From: Gou Hao <gouhao@xxxxxxxxxxxxx>

If 'bh' is found in cache, just return directly.
might_sleep() is only required on slow paths.

Signed-off-by: Gou Hao <gouhao@xxxxxxxxxxxxx>
---
 fs/buffer.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/fs/buffer.c b/fs/buffer.c
index 9e1e2add541e..e13eff504fb5 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -1371,10 +1371,11 @@ __getblk_gfp(struct block_device *bdev, sector_t block,
 {
 	struct buffer_head *bh = __find_get_block(bdev, block, size);
 
+	if (bh)
+		return bh;
+
 	might_sleep();
-	if (bh == NULL)
-		bh = __getblk_slow(bdev, block, size, gfp);
-	return bh;
+	return __getblk_slow(bdev, block, size, gfp);
 }
 EXPORT_SYMBOL(__getblk_gfp);
 
-- 
2.20.1