linux-kernel - [PATCH 10/15] GFS2: Optimize glock multiple-dequeue code

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 15 Mar 2011 09:11:40 +0000
From:	Steven Whitehouse <swhiteho@...hat.com>
To:	cluster-devel@...hat.com, linux-kernel@...r.kernel.org
Cc:	Bob Peterson <rpeterso@...hat.com>,
	Steven Whitehouse <swhiteho@...hat.com>
Subject: [PATCH 10/15] GFS2: Optimize glock multiple-dequeue code

From: Bob Peterson <rpeterso@...hat.com>

This is a small patch that optimizes multiple glock dequeue
operations.  It changes the unlock order to be more efficient
and makes it easier for lock debugging tools to unravel.  It
also eliminates the need for the temp variable x, although
that would likely be optimized out.

Signed-off-by: Bob Peterson <rpeterso@...hat.com>
Signed-off-by: Steven Whitehouse <swhiteho@...hat.com>

diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 3f45a14..8648409 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -1248,10 +1248,8 @@ int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs)
 
 void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs)
 {
-	unsigned int x;
-
-	for (x = 0; x < num_gh; x++)
-		gfs2_glock_dq(&ghs[x]);
+	while (num_gh--)
+		gfs2_glock_dq(&ghs[num_gh]);
 }
 
 /**
@@ -1263,10 +1261,8 @@ void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs)
 
 void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs)
 {
-	unsigned int x;
-
-	for (x = 0; x < num_gh; x++)
-		gfs2_glock_dq_uninit(&ghs[x]);
+	while (num_gh--)
+		gfs2_glock_dq_uninit(&ghs[num_gh]);
 }
 
 void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state)
-- 
1.7.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/