[PATCH 1/2] net/mana: avoid unnecessary assignments in data path

[longli@linuxonhyperv.com]

From: Long Li <longli@microsoft.com>

Unnecessary assignments involve memset and waste CPU cycles.
Removing them to reduce CPU usage.

Fixes: 517ed6e2d590 ("net/mana: add basic driver with build environment")
Cc: stable@dpdk.org
Signed-off-by: Long Li <longli@microsoft.com>
---
 drivers/net/mana/gdma.c | 11 ++---------
 drivers/net/mana/mana.h |  2 +-
 drivers/net/mana/rx.c   |  9 ++++-----
 drivers/net/mana/tx.c   | 17 ++++++++++-------
 4 files changed, 17 insertions(+), 22 deletions(-)

diff --git a/drivers/net/mana/gdma.c b/drivers/net/mana/gdma.c
index 3d4039014f..0922463ef9 100644
--- a/drivers/net/mana/gdma.c
+++ b/drivers/net/mana/gdma.c
@@ -123,7 +123,7 @@ write_scatter_gather_list(uint8_t *work_queue_head_pointer,
 int
 gdma_post_work_request(struct mana_gdma_queue *queue,
 		       struct gdma_work_request *work_req,
-		       struct gdma_posted_wqe_info *wqe_info)
+		       uint32_t *wqe_size_in_bu)
 {
 	uint32_t client_oob_size =
 		work_req->inline_oob_size_in_bytes >
@@ -149,14 +149,7 @@ gdma_post_work_request(struct mana_gdma_queue *queue,
 	DRV_LOG(DEBUG, "client_oob_size %u sgl_data_size %u wqe_size %u",
 		client_oob_size, sgl_data_size, wqe_size);
 
-	if (wqe_info) {
-		wqe_info->wqe_index =
-			((queue->head * GDMA_WQE_ALIGNMENT_UNIT_SIZE) &
-			 (queue->size - 1)) / GDMA_WQE_ALIGNMENT_UNIT_SIZE;
-		wqe_info->unmasked_queue_offset = queue->head;
-		wqe_info->wqe_size_in_bu =
-			wqe_size / GDMA_WQE_ALIGNMENT_UNIT_SIZE;
-	}
+	*wqe_size_in_bu = wqe_size / GDMA_WQE_ALIGNMENT_UNIT_SIZE;
 
 	wq_buffer_pointer = gdma_get_wqe_pointer(queue);
 	wq_buffer_pointer += write_dma_client_oob(wq_buffer_pointer, work_req,
diff --git a/drivers/net/mana/mana.h b/drivers/net/mana/mana.h
index 4a05238a96..d4a1ba8492 100644
--- a/drivers/net/mana/mana.h
+++ b/drivers/net/mana/mana.h
@@ -459,7 +459,7 @@ int mana_rq_ring_doorbell(struct mana_rxq *rxq, uint8_t arm);
 
 int gdma_post_work_request(struct mana_gdma_queue *queue,
 			   struct gdma_work_request *work_req,
-			   struct gdma_posted_wqe_info *wqe_info);
+			   uint32_t *wqe_size_in_bu);
 uint8_t *gdma_get_wqe_pointer(struct mana_gdma_queue *queue);
 
 uint16_t mana_rx_burst(void *dpdk_rxq, struct rte_mbuf **rx_pkts,
diff --git a/drivers/net/mana/rx.c b/drivers/net/mana/rx.c
index 55247889c1..bdbd11c5f9 100644
--- a/drivers/net/mana/rx.c
+++ b/drivers/net/mana/rx.c
@@ -52,8 +52,8 @@ mana_alloc_and_post_rx_wqe(struct mana_rxq *rxq)
 {
 	struct rte_mbuf *mbuf = NULL;
 	struct gdma_sgl_element sgl[1];
-	struct gdma_work_request request = {0};
-	struct gdma_posted_wqe_info wqe_info = {0};
+	struct gdma_work_request request;
+	uint32_t wqe_size_in_bu;
 	struct mana_priv *priv = rxq->priv;
 	int ret;
 	struct mana_mr_cache *mr;
@@ -72,7 +72,6 @@ mana_alloc_and_post_rx_wqe(struct mana_rxq *rxq)
 	}
 
 	request.gdma_header.struct_size = sizeof(request);
-	wqe_info.gdma_header.struct_size = sizeof(wqe_info);
 
 	sgl[0].address = rte_cpu_to_le_64(rte_pktmbuf_mtod(mbuf, uint64_t));
 	sgl[0].memory_key = mr->lkey;
@@ -87,14 +86,14 @@ mana_alloc_and_post_rx_wqe(struct mana_rxq *rxq)
 	request.flags = 0;
 	request.client_data_unit = NOT_USING_CLIENT_DATA_UNIT;
 
-	ret = gdma_post_work_request(&rxq->gdma_rq, &request, &wqe_info);
+	ret = gdma_post_work_request(&rxq->gdma_rq, &request, &wqe_size_in_bu);
 	if (!ret) {
 		struct mana_rxq_desc *desc =
 			&rxq->desc_ring[rxq->desc_ring_head];
 
 		/* update queue for tracking pending packets */
 		desc->pkt = mbuf;
-		desc->wqe_size_in_bu = wqe_info.wqe_size_in_bu;
+		desc->wqe_size_in_bu = wqe_size_in_bu;
 		rxq->desc_ring_head = (rxq->desc_ring_head + 1) % rxq->num_desc;
 	} else {
 		DRV_LOG(ERR, "failed to post recv ret %d", ret);
diff --git a/drivers/net/mana/tx.c b/drivers/net/mana/tx.c
index 300bf27cc1..a7ee47c582 100644
--- a/drivers/net/mana/tx.c
+++ b/drivers/net/mana/tx.c
@@ -208,8 +208,8 @@ mana_tx_burst(void *dpdk_txq, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
 	for (uint16_t pkt_idx = 0; pkt_idx < nb_pkts; pkt_idx++) {
 		struct rte_mbuf *m_pkt = tx_pkts[pkt_idx];
 		struct rte_mbuf *m_seg = m_pkt;
-		struct transmit_oob_v2 tx_oob = {0};
-		struct one_sgl sgl = {0};
+		struct transmit_oob_v2 tx_oob;
+		struct one_sgl sgl;
 		uint16_t seg_idx;
 
 		/* Drop the packet if it exceeds max segments */
@@ -263,6 +263,8 @@ mana_tx_burst(void *dpdk_txq, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
 			tx_oob.short_oob.tx_compute_TCP_checksum = 1;
 			tx_oob.short_oob.tx_transport_header_offset =
 				m_pkt->l2_len + m_pkt->l3_len;
+		} else {
+			tx_oob.short_oob.tx_compute_TCP_checksum = 0;
 		}
 
 		if ((m_pkt->ol_flags & RTE_MBUF_F_TX_L4_MASK) ==
@@ -301,6 +303,8 @@ mana_tx_burst(void *dpdk_txq, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
 			}
 
 			tx_oob.short_oob.tx_compute_UDP_checksum = 1;
+		} else {
+			tx_oob.short_oob.tx_compute_UDP_checksum = 0;
 		}
 
 		tx_oob.short_oob.suppress_tx_CQE_generation = 0;
@@ -355,11 +359,10 @@ mana_tx_burst(void *dpdk_txq, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
 		if (seg_idx != m_pkt->nb_segs)
 			continue;
 
-		struct gdma_work_request work_req = {0};
-		struct gdma_posted_wqe_info wqe_info = {0};
+		struct gdma_work_request work_req;
+		uint32_t wqe_size_in_bu;
 
 		work_req.gdma_header.struct_size = sizeof(work_req);
-		wqe_info.gdma_header.struct_size = sizeof(wqe_info);
 
 		work_req.sgl = sgl.gdma_sgl;
 		work_req.num_sgl_elements = m_pkt->nb_segs;
@@ -370,14 +373,14 @@ mana_tx_burst(void *dpdk_txq, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
 		work_req.client_data_unit = NOT_USING_CLIENT_DATA_UNIT;
 
 		ret = gdma_post_work_request(&txq->gdma_sq, &work_req,
-					     &wqe_info);
+					     &wqe_size_in_bu);
 		if (!ret) {
 			struct mana_txq_desc *desc =
 				&txq->desc_ring[txq->desc_ring_head];
 
 			/* Update queue for tracking pending requests */
 			desc->pkt = m_pkt;
-			desc->wqe_size_in_bu = wqe_info.wqe_size_in_bu;
+			desc->wqe_size_in_bu = wqe_size_in_bu;
 			txq->desc_ring_head =
 				(txq->desc_ring_head + 1) % txq->num_desc;
 
-- 
2.32.0