dlm: fix QUECVT when convert queue is empty

The QUECVT flag should not prevent conversions from
being granted immediately when the convert queue is
empty.

Signed-off-by: David Teigland <teigland@redhat.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c
index fa5c07d51dcc..4c58d4a3adc4 100644
--- a/fs/dlm/lock.c
+++ b/fs/dlm/lock.c
@@ -1737,6 +1737,18 @@ static int _can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now)
                 return 1;
 
         /*
+         * Even if the convert is compat with all granted locks,
+         * QUECVT forces it behind other locks on the convert queue.
+         */
+
+        if (now && conv && (lkb->lkb_exflags & DLM_LKF_QUECVT)) {
+                if (list_empty(&r->res_convertqueue))
+                        return 1;
+                else
+                        goto out;
+        }
+
+        /*
          * The NOORDER flag is set to avoid the standard vms rules on grant
          * order.
          */