The patch titled
Subject: ocfs2/cluster: close a race that fence can't be triggered
has been added to the -mm tree. Its filename is
ocfs2-cluster-close-a-race-that-fence-cant-be-triggered.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/ocfs2-cluster-close-a-race-that-fence-cant-be-triggered.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/ocfs2-cluster-close-a-race-that-fence-cant-be-triggered.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Yang Zhang <zhang.yangB@xxxxxxx>
Subject: ocfs2/cluster: close a race that fence can't be triggered
When some nodes of cluster face with TCP connection fault, ocfs2 will pick
up a quorum to continue to work and other nodes will be fenced by
resetting host.
In order to decide which node should be fenced, ocfs2 leverages
o2quo_state::qs_holds. If that variable is reduced to zero, then a try to
decide if fence local node is performed. However, under a specific
scenario that local node is not disconnected from others at the same time,
above method has a problem to reduce ::qs_holds to zero.
Because, o2net 90s idle timer corresponding to different nodes is
triggered one after another.
node 2 node 3
90s idle timer elapses
clear ::qs_conn_bm
set hold
40s is passed
90 idle timer elapses
clear ::qs_conn_bm
set hold
still up timer elapses
clear hold (NOT to zero )
90s idle timer elapses AGAIN
still up timer elapses.
clear hold
still up timer elapses
To solve this issue, a node which has already be evicted from ::qs_conn_bm
can't set hold again and again invoked from idle timer.
Link: http://lkml.kernel.org/r/63ADC13FD55D6546B7DECE290D39E373F1F3F93B@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Yang Zhang <zhang.yangB@xxxxxxx>
Signed-off-by: Changwei Ge <ge.changwei@xxxxxxx>
Cc: Mark Fasheh <mfasheh@xxxxxxxxxxx>
Cc: Joel Becker <jlbec@xxxxxxxxxxxx>
Cc: Junxiao Bi <junxiao.bi@xxxxxxxxxx>
Cc: Joseph Qi <jiangqi903@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/ocfs2/cluster/quorum.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff -puN fs/ocfs2/cluster/quorum.c~ocfs2-cluster-close-a-race-that-fence-cant-be-triggered fs/ocfs2/cluster/quorum.c
--- a/fs/ocfs2/cluster/quorum.c~ocfs2-cluster-close-a-race-that-fence-cant-be-triggered
+++ a/fs/ocfs2/cluster/quorum.c
@@ -314,12 +314,13 @@ void o2quo_conn_err(u8 node)
node, qs->qs_connected);
clear_bit(node, qs->qs_conn_bm);
+
+ if (test_bit(node, qs->qs_hb_bm))
+ o2quo_set_hold(qs, node);
}
mlog(0, "node %u, %d total\n", node, qs->qs_connected);
- if (test_bit(node, qs->qs_hb_bm))
- o2quo_set_hold(qs, node);
spin_unlock(&qs->qs_lock);
}
_
Patches currently in -mm which might be from zhang.yangB@xxxxxxx are
ocfs2-cluster-close-a-race-that-fence-cant-be-triggered.patch
ocfs2-fix-qs_holds-may-could-not-be-zero.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
