[PATCH v4 2/3] test: generate larger packet bursts

[Stephen Hemminger <stephen@networkplumber.org>]

The packet length in packet burst generator was uint8_t which
limited usefulness for testing larger packet sizes.

The number of packets segments per packet is currently limited
by mbuf nb_segs which is 16 bits. The comment is incorrect.

Change nb_pkt_per_burst to uint16_t since that is the limit
for tx_burst.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
 app/test/packet_burst_generator.c | 38 +++++++++++++++++--------------
 app/test/packet_burst_generator.h |  4 ++--
 2 files changed, 23 insertions(+), 19 deletions(-)

diff --git a/app/test/packet_burst_generator.c b/app/test/packet_burst_generator.c
index 4c17737739..548296e33e 100644
--- a/app/test/packet_burst_generator.c
+++ b/app/test/packet_burst_generator.c
@@ -205,24 +205,23 @@ initialize_ipv4_header_proto(struct rte_ipv4_hdr *ip_hdr, uint32_t src_addr,
 	return pkt_len;
 }
 
-/*
- * The maximum number of segments per packet is used when creating
- * scattered transmit packets composed of a list of mbufs.
- */
-#define RTE_MAX_SEGS_PER_PKT 255 /**< pkt.nb_segs is a 8-bit unsigned char. */
-
 
 int
 generate_packet_burst(struct rte_mempool *mp, struct rte_mbuf **pkts_burst,
 		struct rte_ether_hdr *eth_hdr, uint8_t vlan_enabled,
 		void *ip_hdr, uint8_t ipv4, struct rte_udp_hdr *udp_hdr,
-		int nb_pkt_per_burst, uint8_t pkt_len, uint8_t nb_pkt_segs)
+		uint16_t nb_pkt_per_burst, uint16_t pkt_len, uint16_t nb_pkt_segs)
 {
-	const uint8_t pkt_seg_data_len = pkt_len / nb_pkt_segs;
+	int i, nb_pkt = 0;
+	size_t eth_hdr_size;
 	struct rte_mbuf *pkt_seg;
 	struct rte_mbuf *pkt;
-	size_t eth_hdr_size;
-	int i, nb_pkt = 0;
+	uint16_t pkt_seg_data_len;
+	uint16_t last_seg_data_len;
+
+	/* Calculate per-segment data length */
+	pkt_seg_data_len = pkt_len / nb_pkt_segs;
+	last_seg_data_len = pkt_seg_data_len + (pkt_len % nb_pkt_segs);
 
 	for (nb_pkt = 0; nb_pkt < nb_pkt_per_burst; nb_pkt++) {
 		pkt = rte_pktmbuf_alloc(mp);
@@ -243,10 +242,10 @@ generate_packet_burst(struct rte_mempool *mp, struct rte_mbuf **pkts_burst,
 				goto nomore_mbuf;
 			}
 			pkt_seg = pkt_seg->next;
-			if (i != nb_pkt_segs - 1)
+			if (i != (int)(nb_pkt_segs - 1))
 				pkt_seg->data_len = pkt_seg_data_len;
 			else
-				pkt_seg->data_len = pkt_seg_data_len + pkt_len % nb_pkt_segs;
+				pkt_seg->data_len = last_seg_data_len;
 		}
 		pkt_seg->next = NULL; /* Last segment of packet. */
 
@@ -300,13 +299,18 @@ generate_packet_burst_proto(struct rte_mempool *mp,
 		struct rte_mbuf **pkts_burst, struct rte_ether_hdr *eth_hdr,
 		uint8_t vlan_enabled, void *ip_hdr,
 		uint8_t ipv4, uint8_t proto, void *proto_hdr,
-		int nb_pkt_per_burst, uint8_t pkt_len, uint8_t nb_pkt_segs)
+		uint16_t nb_pkt_per_burst, uint16_t pkt_len, uint16_t nb_pkt_segs)
 {
-	const uint8_t pkt_seg_data_len = pkt_len / nb_pkt_segs;
+	int i, nb_pkt = 0;
+	size_t eth_hdr_size;
 	struct rte_mbuf *pkt_seg;
 	struct rte_mbuf *pkt;
-	size_t eth_hdr_size;
-	int i, nb_pkt = 0;
+	uint16_t pkt_seg_data_len;
+	uint16_t last_seg_data_len;
+
+	/* Calculate per-segment data length */
+	pkt_seg_data_len = pkt_len / nb_pkt_segs;
+	last_seg_data_len = pkt_seg_data_len + (pkt_len % nb_pkt_segs);
 
 	for (nb_pkt = 0; nb_pkt < nb_pkt_per_burst; nb_pkt++) {
 		pkt = rte_pktmbuf_alloc(mp);
@@ -330,7 +334,7 @@ generate_packet_burst_proto(struct rte_mempool *mp,
 			if (i != nb_pkt_segs - 1)
 				pkt_seg->data_len = pkt_seg_data_len;
 			else
-				pkt_seg->data_len = pkt_seg_data_len + pkt_len % nb_pkt_segs;
+				pkt_seg->data_len = last_seg_data_len;
 		}
 		pkt_seg->next = NULL; /* Last segment of packet. */
 
diff --git a/app/test/packet_burst_generator.h b/app/test/packet_burst_generator.h
index cce41bcd0f..bc16764e77 100644
--- a/app/test/packet_burst_generator.h
+++ b/app/test/packet_burst_generator.h
@@ -62,14 +62,14 @@ int
 generate_packet_burst(struct rte_mempool *mp, struct rte_mbuf **pkts_burst,
 		struct rte_ether_hdr *eth_hdr, uint8_t vlan_enabled,
 		void *ip_hdr, uint8_t ipv4, struct rte_udp_hdr *udp_hdr,
-		int nb_pkt_per_burst, uint8_t pkt_len, uint8_t nb_pkt_segs);
+		uint16_t nb_pkt_per_burst, uint16_t pkt_len, uint16_t nb_pkt_segs);
 
 int
 generate_packet_burst_proto(struct rte_mempool *mp,
 		struct rte_mbuf **pkts_burst, struct rte_ether_hdr *eth_hdr,
 		uint8_t vlan_enabled, void *ip_hdr,
 		uint8_t ipv4, uint8_t proto, void *proto_hdr,
-		int nb_pkt_per_burst, uint8_t pkt_len, uint8_t nb_pkt_segs);
+		uint16_t nb_pkt_per_burst, uint16_t pkt_len, uint16_t nb_pkt_segs);
 
 #ifdef __cplusplus
 }
-- 
2.51.0