[dpdk-dev] [PATCH] net/mlx5: fix info about Rx descriptors for MPRQ

[Alexander Kozyrev]

Numbers of descriptors configured is returned to a user
via rxq_info_get API. This number is incorrect for MPRQ.
For SPRQ this number matches the number of mbufs allocated.
For MPRQ we have fewer external MPRQ buffers that can hold
multiple packets in strides os this big buffer. Take that
into account and return teh number of MPRQ buffers multiplied
by the number of strides in this case.

Fixes: 26f1bae837 ("net/mlx5: add Rx/Tx burst mode info")
Cc: stable at dpdk.org

Signed-off-by: Alexander Kozyrev <akozyrev at nvidia.com>
---
 drivers/net/mlx5/mlx5_rxtx.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/mlx5/mlx5_rxtx.c b/drivers/net/mlx5/mlx5_rxtx.c
index 3aee8d4def..f90124a2aa 100644
--- a/drivers/net/mlx5/mlx5_rxtx.c
+++ b/drivers/net/mlx5/mlx5_rxtx.c
@@ -566,7 +566,9 @@ mlx5_rxq_info_get(struct rte_eth_dev *dev, uint16_t rx_queue_id,
 	qinfo->conf.rx_deferred_start = rxq_ctrl ? 0 : 1;
 	qinfo->conf.offloads = dev->data->dev_conf.rxmode.offloads;
 	qinfo->scattered_rx = dev->data->scattered_rx;
-	qinfo->nb_desc = 1 << rxq->elts_n;
+	qinfo->nb_desc = mlx5_rxq_mprq_enabled(&rxq_ctrl->rxq) ?
+		(1 << rxq->elts_n) * (1 << rxq->strd_num_n) :
+		(1 << rxq->elts_n);
 }
 
 /**
-- 
2.24.1