| Message ID | 521C446D.8000500@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, 27 Aug 2013 14:17:17 +0800 Joseph Qi <joseph.qi@huawei.com> wrote: > Signed-off-by: Joyce <xuejiufei@huawei.com> > Signed-off-by: Joseph Qi <joseph.qi@huawei.com> This signoff trail makes me wonder: which of you was the primary author of this patch?
On 2013/8/28 4:54, Andrew Morton wrote: > On Tue, 27 Aug 2013 14:17:17 +0800 Joseph Qi <joseph.qi@huawei.com> wrote: > >> Signed-off-by: Joyce <xuejiufei@huawei.com> >> Signed-off-by: Joseph Qi <joseph.qi@huawei.com> > > This signoff trail makes me wonder: which of you was the primary > author of this patch? > > Sorry for the misleading signoff trail. Joyce fixed this bug and I rearranged the patch and sent it. Please refer Joyce as the primary author, thanks.
On Wed, 28 Aug 2013 09:59:21 +0800 Joseph Qi <joseph.qi@huawei.com> wrote: > On 2013/8/28 4:54, Andrew Morton wrote: > > On Tue, 27 Aug 2013 14:17:17 +0800 Joseph Qi <joseph.qi@huawei.com> wrote: > > > >> Signed-off-by: Joyce <xuejiufei@huawei.com> > >> Signed-off-by: Joseph Qi <joseph.qi@huawei.com> > > > > This signoff trail makes me wonder: which of you was the primary > > author of this patch? > > > > > Sorry for the misleading signoff trail. Joyce fixed this bug and I > rearranged the patch and sent it. > Please refer Joyce as the primary author, thanks. No problems. Damn, am I good, or what ;) The way to handle this situation is to put an explicit From:Joyce line at the very start of the changelog. If that is present, the person who receives the patch should prioritize that From: line over the one which is present in the email envelope.
diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c index 42252bf..af5cd3b 100644 --- a/fs/ocfs2/cluster/heartbeat.c +++ b/fs/ocfs2/cluster/heartbeat.c @@ -641,16 +641,9 @@ static void o2hb_fire_callbacks(struct o2hb_callback *hbcall, /* Will run the list in order until we process the passed event */ static void o2hb_run_event_list(struct o2hb_node_event *queued_event) { - int empty; struct o2hb_callback *hbcall; struct o2hb_node_event *event; - spin_lock(&o2hb_live_lock); - empty = list_empty(&queued_event->hn_item); - spin_unlock(&o2hb_live_lock); - if (empty) - return; - /* Holding callback sem assures we don't alter the callback * lists when doing this, and serializes ourselves with other * processes wanting callbacks. */ @@ -709,6 +702,7 @@ static void o2hb_shutdown_slot(struct o2hb_disk_slot *slot) struct o2hb_node_event event = { .hn_item = LIST_HEAD_INIT(event.hn_item), }; struct o2nm_node *node; + int queued = 0; node = o2nm_get_node_by_num(slot->ds_node_num); if (!node) @@ -726,11 +720,13 @@ static void o2hb_shutdown_slot(struct o2hb_disk_slot *slot) o2hb_queue_node_event(&event, O2HB_NODE_DOWN_CB, node, slot->ds_node_num); + queued = 1; } } spin_unlock(&o2hb_live_lock); - o2hb_run_event_list(&event); + if (queued) + o2hb_run_event_list(&event); o2nm_node_put(node); } @@ -790,6 +786,7 @@ static int o2hb_check_slot(struct o2hb_region *reg, unsigned int dead_ms = o2hb_dead_threshold * O2HB_REGION_TIMEOUT_MS; unsigned int slot_dead_ms; int tmp; + int queued = 0; memcpy(hb_block, slot->ds_raw_block, reg->hr_block_bytes); @@ -883,6 +880,7 @@ fire_callbacks: slot->ds_node_num); changed = 1; + queued = 1; } list_add_tail(&slot->ds_live_item, @@ -934,6 +932,7 @@ fire_callbacks: node, slot->ds_node_num); changed = 1; + queued = 1; } /* We don't clear this because the node is still @@ -949,7 +948,8 @@ fire_callbacks: out: spin_unlock(&o2hb_live_lock); - o2hb_run_event_list(&event); + if (queued) + o2hb_run_event_list(&event); if (node) o2nm_node_put(node);
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 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> --- fs/ocfs2/cluster/heartbeat.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) -- 1.7.9.7