From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bob Peterson <rpeterso@redhat.com>
Date: Wed, 22 Aug 2007 11:15:29 -0500
Subject: [Cluster-devel] [PATCH] GFS2: Patch to protect sd_log_num_jdata
Message-ID: <1187799330.15734.21.camel@technetium.msp.redhat.com>
List-Id: <cluster-devel.redhat.com>
To: cluster-devel.redhat.com
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Hi,

This is a patch to GFS2 to protect sd_log_num_jdata with the
gfs2_log_lock.  Without this patch, there is a timing window
where you can get hit the following assert from function
gfs2_log_flush():

gfs2_assert_withdraw(sdp,
			sdp->sd_log_num_buf + sdp->sd_log_num_jdata ==
			sdp->sd_log_commited_buf +
			sdp->sd_log_commited_databuf);

I've tested it on my roth cluster and it fixes the problem.

Regards,

Bob Peterson
--
diff -pur a/fs/gfs2/lops.c b/fs/gfs2/lops.c
--- a/fs/gfs2/lops.c	2007-08-21 18:01:07.000000000 -0500
+++ b/fs/gfs2/lops.c	2007-08-21 18:13:33.000000000 -0500
@@ -492,11 +492,12 @@ static void databuf_lo_add(struct gfs2_s
 
 	gfs2_trans_add_gl(bd->bd_gl);
 	if (gfs2_is_jdata(ip)) {
-		sdp->sd_log_num_jdata++;
 		gfs2_pin(sdp, bd->bd_bh);
 		tr->tr_num_databuf_new++;
 	}
 	gfs2_log_lock(sdp);
+	if (gfs2_is_jdata(ip))
+		sdp->sd_log_num_jdata++;
 	sdp->sd_log_num_databuf++;
 	list_add(&le->le_list, &sdp->sd_log_le_databuf);
 	gfs2_log_unlock(sdp);