Commit 2cdc98aa authored Oct 31, 2006 by David Teigland Committed by Steven Whitehouse Nov 30, 2006

[DLM] fix stopping unstarted recovery

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>

parent 91c0dc93

fs/dlm/recoverd.c

+6 −1

Original line number	Diff line number	Diff line
		@@ -219,6 +219,10 @@ static int ls_recover(struct dlm_ls ls, struct dlm_recover rv)
		return error;
		}

		/* The dlm_ls_start() that created the rv we take here may already have been
		stopped via dlm_ls_stop(); in that case we need to leave the RECOVERY_STOP
		flag set. */

		static void do_ls_recovery(struct dlm_ls *ls)
		{
		struct dlm_recover *rv = NULL;
		@@ -226,6 +230,7 @@ static void do_ls_recovery(struct dlm_ls *ls)
		spin_lock(&ls->ls_recover_lock);
		rv = ls->ls_recover_args;
		ls->ls_recover_args = NULL;
		if (rv && ls->ls_recover_seq == rv->seq)
		clear_bit(LSFL_RECOVERY_STOP, &ls->ls_flags);
		spin_unlock(&ls->ls_recover_lock);