diff mbox

[16/22] ocfs2/dlm: force clean refmap when doing local cleanup

Message ID 20130827210510.4BF775A4282@corp2gmr1-2.hot.corp.google.com (mailing list archive)
State New, archived
Headers show

Commit Message

Andrew Morton Aug. 27, 2013, 9:05 p.m. UTC
From: Xue jiufei <xuejiufei@huawei.com>
Subject: ocfs2/dlm: force clean refmap when doing local cleanup

dlm_do_local_recovery_cleanup() should force clean refmap if the owner of
lockres is UNKNOWN.  Otherwise node may hang when umounting filesystems. 
Here's the situation:

	Node1                                    Node2
  -> dlm_get_lock_resource()
other nodes.

                                       trying to master this lockres,
                                       return MAYBE.

selected as the master of lockresA,
set mle->master to Node1,
and do assert_master,
                                       Node 2 has interest on lockresA
                                       and return
                                       then something happened and
                                       Node2 crashed.

Receiving DLM_ASSERT_RESPONSE_MASTERY_REF, set Node2 into refmap, and keep
sending DLM_ASSERT_MASTER_MSG to other nodes

o2hb found node2 down, calling dlm_hb_node_down() -->
dlm_do_local_recovery_cleanup() the master of lockresA is still UNKNOWN,
no need to call dlm_free_dead_locks().

Set the master of lockresA to Node1, but Node2 stills remains in refmap.

When Node1 umount, it found that the refmap of lockresA is not empty and
attempted to migrate it to Node2, But Node2 is already down, so umount
hang, trying to migrate lockresA again and again.

Signed-off-by: joyce <xuejiufei@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

 fs/ocfs2/dlm/dlmrecovery.c |    8 ++++++++
 1 file changed, 8 insertions(+)
diff mbox


diff -puN fs/ocfs2/dlm/dlmrecovery.c~ocfs2-dlm-force-clean-refmap-when-doing-local-cleanup fs/ocfs2/dlm/dlmrecovery.c
--- a/fs/ocfs2/dlm/dlmrecovery.c~ocfs2-dlm-force-clean-refmap-when-doing-local-cleanup
+++ a/fs/ocfs2/dlm/dlmrecovery.c
@@ -2331,6 +2331,14 @@  static void dlm_do_local_recovery_cleanu
 			} else if (res->owner == dlm->node_num) {
 				dlm_free_dead_locks(dlm, res, dead_node);
 				__dlm_lockres_calc_usage(dlm, res);
+			} else if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) {
+				if (test_bit(dead_node, res->refmap)) {
+					mlog(0, "%s:%.*s: dead node %u had a ref, but had "
+						"no locks and had not purged before dying\n",
+						dlm->name, res->lockname.len,
+						res->lockname.name, dead_node);
+					dlm_lockres_clear_refmap_bit(dlm, res, dead_node);
+				}