kernel-fxtec-pro1x/fs/ocfs2/cluster
Joyce 6f8648e894 ocfs2: fix a tiny race case when firing callbacks
In o2hb_shutdown_slot() and o2hb_check_slot(), since event is defined as
local, it is only valid during the call stack.  So the following tiny race
case may happen in a multi-volumes mounted environment:

o2hb-vol1                         o2hb-vol2
1) o2hb_shutdown_slot
allocate local event1
2) queue_node_event
add event1 to global o2hb_node_events
                                  3) o2hb_shutdown_slot
                                  allocate local event2
                                  4) queue_node_event
                                  add event2 to global o2hb_node_events
                                  5) o2hb_run_event_list
                                  delete event1 from o2hb_node_events
6) o2hb_run_event_list
event1 empty, return
7) o2hb_shutdown_slot
event1 lifecycle ends
                                  8) o2hb_fire_callbacks
                                  event1 is already *invalid*

This patch lets it wait on o2hb_callback_sem when another thread is firing
callbacks.  And for performance consideration, we only call
o2hb_run_event_list when there is an event queued.

Signed-off-by: Joyce <xuejiufei@huawei.com>
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 15:56:51 -07:00
..
heartbeat.c ocfs2: fix a tiny race case when firing callbacks 2013-09-11 15:56:51 -07:00
heartbeat.h
Makefile
masklog.c
masklog.h
netdebug.c switch debugfs to umode_t 2012-01-03 22:54:56 -05:00
nodemanager.c
nodemanager.h
ocfs2_heartbeat.h
ocfs2_nodemanager.h
quorum.c ocfs2: fix a comments typo at o2quo_hb_still_up() 2013-07-03 16:07:24 -07:00
quorum.h
sys.c
sys.h
tcp.c ocfs2: avoid possible NULL pointer dereference in o2net_accept_one() 2013-09-11 15:56:50 -07:00
tcp.h
tcp_internal.h
ver.c
ver.h