From: Eli Cohen Date: Tue, 6 Mar 2012 13:50:51 +0000 (+0200) Subject: IB/mlx4: Fix possible missed completion event X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=3616f9cead935d4e4c35915600d5e4d1384219cd;p=linux-beck.git 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 Signed-off-by: Roland Dreier --- diff --git a/drivers/infiniband/hw/mlx4/cq.c b/drivers/infiniband/hw/mlx4/cq.c index 5ecf38d97269..275861bddf1c 100644 --- a/drivers/infiniband/hw/mlx4/cq.c +++ b/drivers/infiniband/hw/mlx4/cq.c @@ -747,8 +747,7 @@ int mlx4_ib_poll_cq(struct ib_cq *ibcq, int num_entries, struct ib_wc *wc) break; } - if (npolled) - mlx4_cq_set_ci(&cq->mcq); + mlx4_cq_set_ci(&cq->mcq); spin_unlock_irqrestore(&cq->lock, flags);