From 3dca0f42c7baaa4e01699629da13d6556f001ebe Mon Sep 17 00:00:00 2001 From: Matan Barak Date: Thu, 11 Dec 2014 10:57:53 +0200 Subject: net/mlx4_core: Use tasklet for user-space CQ completion events Previously, we've fired all our completion callbacks straight from our ISR. Some of those callbacks were lightweight (for example, mlx4_en's and IPoIB napi callbacks), but some of them did more work (for example, the user-space RDMA stack uverbs' completion handler). Besides that, doing more than the minimal work in ISR is generally considered wrong, it could even lead to a hard lockup of the system. Since when a lot of completion events are generated by the hardware, the loop over those events could be so long, that we'll get into a hard lockup by the system watchdog. In order to avoid that, add a new way of invoking completion events callbacks. In the interrupt itself, we add the CQs which receive completion event to a per-EQ list and schedule a tasklet. In the tasklet context we loop over all the CQs in the list and invoke the user callback. Signed-off-by: Matan Barak Signed-off-by: Or Gerlitz Signed-off-by: David S. Miller --- drivers/infiniband/hw/mlx4/cq.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'drivers/infiniband/hw') diff --git a/drivers/infiniband/hw/mlx4/cq.c b/drivers/infiniband/hw/mlx4/cq.c index 1066eec854a9..a3b70f6c4035 100644 --- a/drivers/infiniband/hw/mlx4/cq.c +++ b/drivers/infiniband/hw/mlx4/cq.c @@ -233,7 +233,10 @@ struct ib_cq *mlx4_ib_create_cq(struct ib_device *ibdev, int entries, int vector if (err) goto err_dbmap; - cq->mcq.comp = mlx4_ib_cq_comp; + if (context) + cq->mcq.tasklet_ctx.comp = mlx4_ib_cq_comp; + else + cq->mcq.comp = mlx4_ib_cq_comp; cq->mcq.event = mlx4_ib_cq_event; if (context) -- cgit v1.2.3