linux-kernel - gfs2: gfs2_dir_get_hash_table(): avoiding deferred vfree() is easy here...

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Message-ID: <20141120051947.GG7996@ZenIV.linux.org.uk>
Date:	Thu, 20 Nov 2014 05:19:47 +0000
From:	Al Viro <viro@...IV.linux.org.uk>
To:	linux-kernel@...r.kernel.org
Cc:	cluster-devel@...hat.com
Subject: gfs2: gfs2_dir_get_hash_table(): avoiding deferred vfree() is easy
 here...

vfree() is allowed under spinlock these days, but it's cheaper when
it doesn't step into deferred case and here it's very easy to avoid.

Signed-off-by: Al Viro <viro@...iv.linux.org.uk>
---
 fs/gfs2/dir.c |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/fs/gfs2/dir.c b/fs/gfs2/dir.c
index c247fed..c5a34f0 100644
--- a/fs/gfs2/dir.c
+++ b/fs/gfs2/dir.c
@@ -370,11 +370,12 @@ static __be64 *gfs2_dir_get_hash_table(struct gfs2_inode *ip)
 	}

 	spin_lock(&inode->i_lock);
-	if (ip->i_hash_cache)
-		kvfree(hc);
-	else
+	if (likely(!ip->i_hash_cache)) {
 		ip->i_hash_cache = hc;
+		hc = NULL;
+	}
 	spin_unlock(&inode->i_lock);
+	kvfree(hc);

 	return ip->i_hash_cache;
 }
-- 
1.7.10.4

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