[dpdk-dev] [PATCH v2 17/23] net/bnxt: fix set MTU

[Ajit Khaparde]

There is no need to update bnxt_hwrm_vnic_plcmode_cfg if new MTU is
not greater than the max data the mbuf can accommodate.

Fixes: daef48efe5e5 ("net/bnxt: support set MTU")
Cc: sta...@dpdk.org

Signed-off-by: Ajit Khaparde <ajit.khapa...@broadcom.com>
--
v1->v2: update commit log
---
 drivers/net/bnxt/bnxt_ethdev.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/net/bnxt/bnxt_ethdev.c b/drivers/net/bnxt/bnxt_ethdev.c
index ab3f5c8e7..fe95e01ca 100644
--- a/drivers/net/bnxt/bnxt_ethdev.c
+++ b/drivers/net/bnxt/bnxt_ethdev.c
@@ -1581,6 +1581,7 @@ static int bnxt_mtu_set_op(struct rte_eth_dev *eth_dev, 
uint16_t new_mtu)
 
        for (i = 0; i < bp->nr_vnics; i++) {
                struct bnxt_vnic_info *vnic = &bp->vnic_info[i];
+               uint16_t size = 0;
 
                vnic->mru = bp->eth_dev->data->mtu + ETHER_HDR_LEN +
                                        ETHER_CRC_LEN + VLAN_TAG_SIZE * 2;
@@ -1588,9 +1589,14 @@ static int bnxt_mtu_set_op(struct rte_eth_dev *eth_dev, 
uint16_t new_mtu)
                if (rc)
                        break;
 
-               rc = bnxt_hwrm_vnic_plcmode_cfg(bp, vnic);
-               if (rc)
-                       return rc;
+               size = rte_pktmbuf_data_room_size(bp->rx_queues[0]->mb_pool);
+               size -= RTE_PKTMBUF_HEADROOM;
+
+               if (size < new_mtu) {
+                       rc = bnxt_hwrm_vnic_plcmode_cfg(bp, vnic);
+                       if (rc)
+                               return rc;
+               }
        }
 
        return rc;
-- 
2.15.2 (Apple Git-101.1)