IB/mlx4: Fix possible missed completion event
If an erroneous CQE is polled in the first iteration (i.e. npolled ==
0), we don't update the consumer index and hence the hardware could
get a wrong notion of how many CQEs software polled. Fix this by
unconditionally updating the doorbell record. We could change the
check to be something like
if (npolled || err != -EAGAIN)
...
but it does not seem worth the effort since a posted write to memory
should not cost too much.
Signed-off-by: Eli Cohen <eli@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
diff --git a/drivers/infiniband/hw/mlx4/cq.c b/drivers/infiniband/hw/mlx4/cq.c
index 5ecf38d..275861b 100644
--- a/drivers/infiniband/hw/mlx4/cq.c
+++ b/drivers/infiniband/hw/mlx4/cq.c
@@ -747,8 +747,7 @@
break;
}
- if (npolled)
- mlx4_cq_set_ci(&cq->mcq);
+ mlx4_cq_set_ci(&cq->mcq);
spin_unlock_irqrestore(&cq->lock, flags);