[RFC PATCH 27/27] net/intel: remove index for tracking end of packet

[Bruce Richardson]

The last_id value in each tx_sw_queue entry was no longer used in the
datapath, remove it and its initialization. For the function releasing
packets back, rather than relying on "last_id" to identify end of
packet, instead check for the next pointer being NULL.

Signed-off-by: Bruce Richardson <bruce.richardson at intel.com>
---
 drivers/net/intel/common/tx.h             | 1 -
 drivers/net/intel/i40e/i40e_rxtx.c        | 8 +++-----
 drivers/net/intel/iavf/iavf_rxtx.c        | 9 ++++-----
 drivers/net/intel/ice/ice_dcf_ethdev.c    | 1 -
 drivers/net/intel/ice/ice_rxtx.c          | 9 ++++-----
 drivers/net/intel/idpf/idpf_common_rxtx.c | 2 --
 drivers/net/intel/ixgbe/ixgbe_rxtx.c      | 9 ++++-----
 7 files changed, 15 insertions(+), 24 deletions(-)

diff --git a/drivers/net/intel/common/tx.h b/drivers/net/intel/common/tx.h
index 3976766f06..2d3626cbda 100644
--- a/drivers/net/intel/common/tx.h
+++ b/drivers/net/intel/common/tx.h
@@ -104,7 +104,6 @@ struct ci_tx_queue;
 struct ci_tx_entry {
 	struct rte_mbuf *mbuf; /* mbuf associated with TX desc, if any. */
 	uint16_t next_id; /* Index of next descriptor in ring. */
-	uint16_t last_id; /* Index of last scattered descriptor. */
 };
 
 /**
diff --git a/drivers/net/intel/i40e/i40e_rxtx.c b/drivers/net/intel/i40e/i40e_rxtx.c
index e1226d649b..9aa31d6168 100644
--- a/drivers/net/intel/i40e/i40e_rxtx.c
+++ b/drivers/net/intel/i40e/i40e_rxtx.c
@@ -2523,14 +2523,13 @@ i40e_tx_done_cleanup_full(struct ci_tx_queue *txq,
 			pkt_cnt < free_cnt &&
 			tx_id != tx_last; i++) {
 			if (swr_ring[tx_id].mbuf != NULL) {
-				rte_pktmbuf_free_seg(swr_ring[tx_id].mbuf);
-				swr_ring[tx_id].mbuf = NULL;
-
 				/*
 				 * last segment in the packet,
 				 * increment packet count
 				 */
-				pkt_cnt += (swr_ring[tx_id].last_id == tx_id);
+				pkt_cnt += (swr_ring[tx_id].mbuf->next == NULL) ? 1 : 0;
+				rte_pktmbuf_free_seg(swr_ring[tx_id].mbuf);
+				swr_ring[tx_id].mbuf = NULL;
 			}
 
 			tx_id = swr_ring[tx_id].next_id;
@@ -2623,7 +2622,6 @@ i40e_reset_tx_queue(struct ci_tx_queue *txq)
 		txd->cmd_type_offset_bsz =
 			rte_cpu_to_le_64(CI_TX_DESC_DTYPE_DESC_DONE);
 		txe[i].mbuf =  NULL;
-		txe[i].last_id = i;
 		txe[prev].next_id = i;
 		prev = i;
 	}
diff --git a/drivers/net/intel/iavf/iavf_rxtx.c b/drivers/net/intel/iavf/iavf_rxtx.c
index 9cac6e8841..558ae2598f 100644
--- a/drivers/net/intel/iavf/iavf_rxtx.c
+++ b/drivers/net/intel/iavf/iavf_rxtx.c
@@ -292,7 +292,6 @@ reset_tx_queue(struct ci_tx_queue *txq)
 		txq->ci_tx_ring[i].cmd_type_offset_bsz =
 			rte_cpu_to_le_64(CI_TX_DESC_DTYPE_DESC_DONE);
 		txe[i].mbuf =  NULL;
-		txe[i].last_id = i;
 		txe[prev].next_id = i;
 		prev = i;
 	}
@@ -4002,14 +4001,14 @@ iavf_tx_done_cleanup_full(struct ci_tx_queue *txq,
 	while (pkt_cnt < free_cnt) {
 		do {
 			if (swr_ring[tx_id].mbuf != NULL) {
-				rte_pktmbuf_free_seg(swr_ring[tx_id].mbuf);
-				swr_ring[tx_id].mbuf = NULL;
-
 				/*
 				 * last segment in the packet,
 				 * increment packet count
 				 */
-				pkt_cnt += (swr_ring[tx_id].last_id == tx_id);
+				pkt_cnt += (swr_ring[tx_id].mbuf->next == NULL) ? 1 : 0;
+				rte_pktmbuf_free_seg(swr_ring[tx_id].mbuf);
+				swr_ring[tx_id].mbuf = NULL;
+
 			}
 
 			tx_id = swr_ring[tx_id].next_id;
diff --git a/drivers/net/intel/ice/ice_dcf_ethdev.c b/drivers/net/intel/ice/ice_dcf_ethdev.c
index 02a23629d6..abd7875e7b 100644
--- a/drivers/net/intel/ice/ice_dcf_ethdev.c
+++ b/drivers/net/intel/ice/ice_dcf_ethdev.c
@@ -408,7 +408,6 @@ reset_tx_queue(struct ci_tx_queue *txq)
 		txq->ci_tx_ring[i].cmd_type_offset_bsz =
 			rte_cpu_to_le_64(CI_TX_DESC_DTYPE_DESC_DONE);
 		txe[i].mbuf =  NULL;
-		txe[i].last_id = i;
 		txe[prev].next_id = i;
 		prev = i;
 	}
diff --git a/drivers/net/intel/ice/ice_rxtx.c b/drivers/net/intel/ice/ice_rxtx.c
index 092981f452..d11d9054f2 100644
--- a/drivers/net/intel/ice/ice_rxtx.c
+++ b/drivers/net/intel/ice/ice_rxtx.c
@@ -1118,7 +1118,6 @@ ice_reset_tx_queue(struct ci_tx_queue *txq)
 		txd->cmd_type_offset_bsz =
 			rte_cpu_to_le_64(CI_TX_DESC_DTYPE_DESC_DONE);
 		txe[i].mbuf =  NULL;
-		txe[i].last_id = i;
 		txe[prev].next_id = i;
 		prev = i;
 	}
@@ -3190,14 +3189,14 @@ ice_tx_done_cleanup_full(struct ci_tx_queue *txq,
 			pkt_cnt < free_cnt &&
 			tx_id != tx_last; i++) {
 			if (swr_ring[tx_id].mbuf != NULL) {
-				rte_pktmbuf_free_seg(swr_ring[tx_id].mbuf);
-				swr_ring[tx_id].mbuf = NULL;
-
 				/*
 				 * last segment in the packet,
 				 * increment packet count
 				 */
-				pkt_cnt += (swr_ring[tx_id].last_id == tx_id);
+				pkt_cnt += swr_ring[tx_id].mbuf->next == NULL ? 1 : 0;
+				rte_pktmbuf_free_seg(swr_ring[tx_id].mbuf);
+				swr_ring[tx_id].mbuf = NULL;
+
 			}
 
 			tx_id = swr_ring[tx_id].next_id;
diff --git a/drivers/net/intel/idpf/idpf_common_rxtx.c b/drivers/net/intel/idpf/idpf_common_rxtx.c
index b36e29c8d2..781310e564 100644
--- a/drivers/net/intel/idpf/idpf_common_rxtx.c
+++ b/drivers/net/intel/idpf/idpf_common_rxtx.c
@@ -218,7 +218,6 @@ idpf_qc_split_tx_descq_reset(struct ci_tx_queue *txq)
 	prev = (uint16_t)(txq->sw_nb_desc - 1);
 	for (i = 0; i < txq->sw_nb_desc; i++) {
 		txe[i].mbuf = NULL;
-		txe[i].last_id = i;
 		txe[prev].next_id = i;
 		prev = i;
 	}
@@ -277,7 +276,6 @@ idpf_qc_single_tx_queue_reset(struct ci_tx_queue *txq)
 		txq->ci_tx_ring[i].cmd_type_offset_bsz =
 			rte_cpu_to_le_64(CI_TX_DESC_DTYPE_DESC_DONE);
 		txe[i].mbuf =  NULL;
-		txe[i].last_id = i;
 		txe[prev].next_id = i;
 		prev = i;
 	}
diff --git a/drivers/net/intel/ixgbe/ixgbe_rxtx.c b/drivers/net/intel/ixgbe/ixgbe_rxtx.c
index 6b8ff20f61..5f4bee4f2f 100644
--- a/drivers/net/intel/ixgbe/ixgbe_rxtx.c
+++ b/drivers/net/intel/ixgbe/ixgbe_rxtx.c
@@ -2407,14 +2407,14 @@ ixgbe_tx_done_cleanup_full(struct ci_tx_queue *txq, uint32_t free_cnt)
 			pkt_cnt < free_cnt &&
 			tx_id != tx_last; i++) {
 			if (swr_ring[tx_id].mbuf != NULL) {
-				rte_pktmbuf_free_seg(swr_ring[tx_id].mbuf);
-				swr_ring[tx_id].mbuf = NULL;
-
 				/*
 				 * last segment in the packet,
 				 * increment packet count
 				 */
-				pkt_cnt += (swr_ring[tx_id].last_id == tx_id);
+				pkt_cnt += swr_ring[tx_id].mbuf->next == NULL ? 1 : 0;
+				rte_pktmbuf_free_seg(swr_ring[tx_id].mbuf);
+				swr_ring[tx_id].mbuf = NULL;
+
 			}
 
 			tx_id = swr_ring[tx_id].next_id;
@@ -2535,7 +2535,6 @@ ixgbe_reset_tx_queue(struct ci_tx_queue *txq)
 
 		txd->wb.status = rte_cpu_to_le_32(IXGBE_TXD_STAT_DD);
 		txe[i].mbuf = NULL;
-		txe[i].last_id = i;
 		txe[prev].next_id = i;
 		prev = i;
 	}
-- 
2.51.0