[dpdk-dev] [PATCH] net/bnxt: don't set mbuf pointers to null in vector PMD

[Lance Richardson]

Remove code for setting consumed mbuf pointers to NULL from the
vector receive functions as a minor performance optimization.

Signed-off-by: Lance Richardson <lance.richardson at broadcom.com>
Reviewed-by: Ajit Kumar Khaparde <ajit.khaparde at broadcom.com>
Reviewed-by: Somnath Kotur <somnath.kotur at broadcom.com>
---
 drivers/net/bnxt/bnxt_rxq.c           | 10 ++++++++++
 drivers/net/bnxt/bnxt_rxtx_vec_neon.c | 17 +----------------
 drivers/net/bnxt/bnxt_rxtx_vec_sse.c  | 17 +----------------
 3 files changed, 12 insertions(+), 32 deletions(-)

diff --git a/drivers/net/bnxt/bnxt_rxq.c b/drivers/net/bnxt/bnxt_rxq.c
index f46b10c1c5..d345c37c8d 100644
--- a/drivers/net/bnxt/bnxt_rxq.c
+++ b/drivers/net/bnxt/bnxt_rxq.c
@@ -212,6 +212,16 @@ void bnxt_rx_queue_release_mbufs(struct bnxt_rx_queue *rxq)
 
 	sw_ring = rxq->rx_ring->rx_buf_ring;
 	if (sw_ring) {
+#if defined(RTE_ARCH_X86) || defined(RTE_ARCH_ARM64)
+		/*
+		 * The vector receive burst function does not set used
+		 * mbuf pointers to NULL, do that here to simplify
+		 * cleanup logic.
+		 */
+		for (i = 0; i < rxq->rxrearm_nb; i++)
+			sw_ring[rxq->rxrearm_start + i] = NULL;
+		rxq->rxrearm_nb = 0;
+#endif
 		for (i = 0;
 		     i < rxq->rx_ring->rx_ring_struct->ring_size; i++) {
 			if (sw_ring[i]) {
diff --git a/drivers/net/bnxt/bnxt_rxtx_vec_neon.c b/drivers/net/bnxt/bnxt_rxtx_vec_neon.c
index b0981da0f4..3d54d9d59d 100644
--- a/drivers/net/bnxt/bnxt_rxtx_vec_neon.c
+++ b/drivers/net/bnxt/bnxt_rxtx_vec_neon.c
@@ -274,22 +274,8 @@ bnxt_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
 		num_valid = (sizeof(uint64_t) / sizeof(uint16_t)) -
 				(__builtin_clzl(valid & desc_valid_mask) / 16);
 
-		switch (num_valid) {
-		case 4:
-			rxr->rx_buf_ring[mbcons + 3] = NULL;
-			/* FALLTHROUGH */
-		case 3:
-			rxr->rx_buf_ring[mbcons + 2] = NULL;
-			/* FALLTHROUGH */
-		case 2:
-			rxr->rx_buf_ring[mbcons + 1] = NULL;
-			/* FALLTHROUGH */
-		case 1:
-			rxr->rx_buf_ring[mbcons + 0] = NULL;
+		if (num_valid == 0)
 			break;
-		case 0:
-			goto out;
-		}
 
 		descs_to_mbufs(rxcmp, rxcmp1, mb_init, &rx_pkts[nb_rx_pkts],
 			       rxr);
@@ -299,7 +285,6 @@ bnxt_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
 			break;
 	}
 
-out:
 	if (nb_rx_pkts) {
 		rxr->rx_raw_prod = RING_ADV(rxr->rx_raw_prod, nb_rx_pkts);
 
diff --git a/drivers/net/bnxt/bnxt_rxtx_vec_sse.c b/drivers/net/bnxt/bnxt_rxtx_vec_sse.c
index 7ae6f5c098..7a58434ce9 100644
--- a/drivers/net/bnxt/bnxt_rxtx_vec_sse.c
+++ b/drivers/net/bnxt/bnxt_rxtx_vec_sse.c
@@ -256,22 +256,8 @@ bnxt_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
 		valid = _mm_cvtsi128_si64(_mm_packs_epi32(info3_v, info3_v));
 		num_valid = __builtin_popcountll(valid & desc_valid_mask);
 
-		switch (num_valid) {
-		case 4:
-			rxr->rx_buf_ring[mbcons + 3] = NULL;
-			/* FALLTHROUGH */
-		case 3:
-			rxr->rx_buf_ring[mbcons + 2] = NULL;
-			/* FALLTHROUGH */
-		case 2:
-			rxr->rx_buf_ring[mbcons + 1] = NULL;
-			/* FALLTHROUGH */
-		case 1:
-			rxr->rx_buf_ring[mbcons + 0] = NULL;
+		if (num_valid == 0)
 			break;
-		case 0:
-			goto out;
-		}
 
 		descs_to_mbufs(rxcmp, rxcmp1, mbuf_init, &rx_pkts[nb_rx_pkts],
 			       rxr);
@@ -281,7 +267,6 @@ bnxt_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
 			break;
 	}
 
-out:
 	if (nb_rx_pkts) {
 		rxr->rx_raw_prod = RING_ADV(rxr->rx_raw_prod, nb_rx_pkts);
 
-- 
2.25.1