[dpdk-dev] [PATCH v1 4/9] net/mlx5: mitigate Rx doorbell memory barrier

[Matan Azrad]

The RQ WQEs must be written in the memory before the HW gets the RQ
doorbell, hence a memory barrier should be triggered after the WQEs
writing and before the doorbell writing.

The current code used rte_wmb barrier which ensures that all the memory
stores were done while it is enough to use rte_cio_wmb barrier for the
local memory stores because the WQEs are in local memory.

CC: stable at dpdk.org

Signed-off-by: Matan Azrad <matan at mellanox.com>
---
 drivers/net/mlx5/mlx5_rxq.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/mlx5/mlx5_rxq.c b/drivers/net/mlx5/mlx5_rxq.c
index b248f38..282295f 100644
--- a/drivers/net/mlx5/mlx5_rxq.c
+++ b/drivers/net/mlx5/mlx5_rxq.c
@@ -1009,7 +1009,7 @@ struct mlx5_rxq_ibv *
 	rxq_data->decompressed = 0;
 	/* Update doorbell counter. */
 	rxq_data->rq_ci = wqe_n >> rxq_data->sges_n;
-	rte_wmb();
+	rte_cio_wmb();
 	*rxq_data->rq_db = rte_cpu_to_be_32(rxq_data->rq_ci);
 	DRV_LOG(DEBUG, "port %u rxq %u updated with %p", dev->data->port_id,
 		idx, (void *)&tmpl);
-- 
1.8.3.1