[Cluster-devel] GFS2: Pre-pull patch posting (fixes)

[Cluster-devel] GFS2: Pre-pull patch posting (fixes)

[Steven Whitehouse]

Hi,

Here are a couple of small fixes which just missed the previous pull
request. Both fairly short and self-explanatory,

Steve.

[Cluster-devel] [PATCH 1/2] GFS2: Wipe directory hash table metadata when deallocating a directory

[Steven Whitehouse]

The deallocation code for directories in GFS2 is largely divided into
two parts. The first part deallocates any directory leaf blocks and
marks the directory as being a regular file when that is complete. The
second stage was identical to deallocating regular files.

Regular files have their data blocks in a different
address space to directories, and thus what would have been normal data
blocks in a regular file (the hash table in a GFS2 directory) were
deallocated correctly. However, a reference to these blocks was left in the
journal (assuming of course that some previous activity had resulted in
those blocks being in the journal or ail list).

This patch uses the i_depth as a test of whether the inode is an
exhash directory (we cannot test the inode type as that has already
been changed to a regular file at this stage in deallocation)

The original issue was reported by Chris Hertel as an issue he encountered
running bonnie++

Reported-by: Christopher R. Hertel <crh@samba.org>
Cc: Abhijith Das <adas@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c
index 74add2d..e65493a 100644
--- a/fs/gfs2/bmap.c
+++ b/fs/gfs2/bmap.c
@@ -780,6 +780,8 @@ static int do_strip(struct gfs2_inode *ip, struct buffer_head *dibh,
 	metadata = (height != ip->i_height - 1);
 	if (metadata)
 		revokes = (height) ? sdp->sd_inptrs : sdp->sd_diptrs;
+	else if (ip->i_depth)
+		revokes = sdp->sd_inptrs;
 
 	if (ip != GFS2_I(sdp->sd_rindex))
 		error = gfs2_rindex_hold(sdp, &ip->i_alloc->al_ri_gh);
diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c
index 7273ad3..9b780df 100644
--- a/fs/gfs2/rgrp.c
+++ b/fs/gfs2/rgrp.c
@@ -1629,6 +1629,10 @@ void __gfs2_free_data(struct gfs2_inode *ip, u64 bstart, u32 blen)
 	gfs2_rgrp_out(rgd, rgd->rd_bits[0].bi_bh->b_data);
 
 	gfs2_trans_add_rg(rgd);
+
+	/* Directories keep their data in the metadata address space */
+	if (ip->i_depth)
+		gfs2_meta_wipe(ip, bstart, blen);
 }
 
 /**
-- 
1.7.4

[Cluster-devel] [PATCH 2/2] GFS2: Wait properly when flushing the ail list

[Steven Whitehouse]

The ail flush code has always relied upon log flushing to prevent
it from spinning needlessly. This fixes it to wait on the last
I/O request submitted (we don't need to wait for all of it)
instead of either spinning with io_schedule or sleeping.

As a result cpu usage of gfs2_logd is much reduced with certain
workloads.

Reported-by: Abhijith Das <adas@redhat.com>
Tested-by: Abhijith Das <adas@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c
index cec26c0..903115f 100644
--- a/fs/gfs2/log.c
+++ b/fs/gfs2/log.c
@@ -228,6 +228,27 @@ static int gfs2_ail1_empty(struct gfs2_sbd *sdp)
 	return ret;
 }
 
+static void gfs2_ail1_wait(struct gfs2_sbd *sdp)
+{
+	struct gfs2_ail *ai;
+	struct gfs2_bufdata *bd;
+	struct buffer_head *bh;
+
+	spin_lock(&sdp->sd_ail_lock);
+	list_for_each_entry_reverse(ai, &sdp->sd_ail1_list, ai_list) {
+		list_for_each_entry(bd, &ai->ai_ail1_list, bd_ail_st_list) {
+			bh = bd->bd_bh;
+			if (!buffer_locked(bh))
+				continue;
+			get_bh(bh);
+			spin_unlock(&sdp->sd_ail_lock);
+			wait_on_buffer(bh);
+			brelse(bh);
+			return;
+		}
+	}
+	spin_unlock(&sdp->sd_ail_lock);
+}
 
 /**
  * gfs2_ail2_empty_one - Check whether or not a trans in the AIL has been synced
@@ -878,9 +899,9 @@ void gfs2_meta_syncfs(struct gfs2_sbd *sdp)
 	gfs2_log_flush(sdp, NULL);
 	for (;;) {
 		gfs2_ail1_start(sdp);
+		gfs2_ail1_wait(sdp);
 		if (gfs2_ail1_empty(sdp))
 			break;
-		msleep(10);
 	}
 }
 
@@ -920,12 +941,14 @@ int gfs2_logd(void *data)
 
 		if (gfs2_ail_flush_reqd(sdp)) {
 			gfs2_ail1_start(sdp);
-			io_schedule();
+			gfs2_ail1_wait(sdp);
 			gfs2_ail1_empty(sdp);
 			gfs2_log_flush(sdp, NULL);
 		}
 
-		wake_up(&sdp->sd_log_waitq);
+		if (!gfs2_ail_flush_reqd(sdp))
+			wake_up(&sdp->sd_log_waitq);
+
 		t = gfs2_tune_get(sdp, gt_logd_secs) * HZ;
 		if (freezing(current))
 			refrigerator();
-- 
1.7.4