Requests that arrive after recovery has started are saved in the
requestqueue and processed after recovery is done. Some of these requests
are purged during recovery if they are from nodes that have been removed.
We move the purging of the requests (dlm_purge_requestqueue) to later in
the recovery sequence which allows the routine saving requests
(dlm_add_requestqueue) to avoid filtering out requests by nodeid since the
same will be done by the purge. The current code has add_requestqueue
filtering by nodeid but doesn't hold any locks when accessing the list of
current nodes. This also means that we need to call the purge routine
when the lockspace is being shut down since the add routine will not be
rejecting requests itself any more.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Red Hat BZ 211914
The previous patch "[DLM] fix aborted recovery during
node removal" was incomplete as discovered with further testing. It set
the bit for the RS_LOCKS barrier but did not then wait for the barrier.
This is often ok, but sometimes it will cause yet another recovery hang.
If it's a new node that also has the lowest nodeid that skips the barrier
wait, then it misses the important step of collecting and reporting the
barrier status from the other nodes (which is the job of the low nodeid in
the barrier wait routine).
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Red Hat BZ 211914
When many nodes are joining a lockspace simultaneously, the dlm gets a
quick sequence of stop/start events, a pair for adding each node.
dlm_controld in user space sends dlm_recoverd in the kernel each stop and
start event. dlm_controld will sometimes send the stop before
dlm_recoverd has had a chance to take up the previously queued start. The
stop aborts the processing of the previous start by setting the
RECOVERY_STOP flag. dlm_recoverd is erroneously clearing this flag and
ignoring the stop/abort if it happens to take up the start after the stop
meant to abort it. The fix is to check the sequence number that's
incremented for each stop/start before clearing the flag.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Red Hat BZ 211914
With the new cluster infrastructure, dlm recovery for a node removal can
be aborted and restarted for a node addition. When this happens, the
restarted recovery isn't aware that it's doing recovery for the earlier
removal as well as the addition. So, it then skips the recovery steps
only required when nodes are removed. This can result in locks not being
purged for failed/removed nodes. The fix is to check for removed nodes
for which recovery has not been completed at the start of a new recovery
sequence.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
When a new lockspace was being created, the recoverd thread was being
started for it before the lockspace was added to the global list of
lockspaces. The new thread was looking up the lockspace in the global
list and sometimes not finding it due to the race with the original thread
adding it to the list. We need to add the lockspace to the global list
before starting the thread instead of after, and if the new thread can't
find the lockspace for some reason, it should return an error.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
When we abort one recovery to do another, break out of the ping_members()
routine more quickly, and wake up the dlm_recoverd thread more quickly
instead of waiting for it to time out.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This is the core of the distributed lock manager which is required
to use GFS2 as a cluster filesystem. It is also used by CLVM and
can be used as a standalone lock manager independantly of either
of these two projects.
It implements VAX-style locking modes.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
David Teigland