[dpdk-dev] [PATCH v3] net/pcap: support buffer size parameter

[Qiming Chen <chenqiming_huawei@163.com>]

When the pcap port is probed, the size of the pcap message buffer is not
set, the default is 2M, and then this value has a great impact on the
message forwarding performance. Therefore, parameters are provided for
users to set.

In order to pass the buffer size parameter parsed by the probe to the
start function, the buf_size member variable is added to the
struct pmd_process_private structure. At the same time, for the uniform
code style, the buf_size member variable is also added to the
struct pmd_devargs structure, which is used by the probe function.

Signed-off-by: Qiming Chen <chenqiming_huawei@163.com>
---
v2:
  Clear coding style warning.
v3:
  When buf_size=0, the modification keeps the old implementation unchanged.
---
 drivers/net/pcap/pcap_ethdev.c | 78 +++++++++++++++++++++++++++++-----
 1 file changed, 68 insertions(+), 10 deletions(-)

diff --git a/drivers/net/pcap/pcap_ethdev.c b/drivers/net/pcap/pcap_ethdev.c
index a8774b7a43..fdc74313d5 100644
--- a/drivers/net/pcap/pcap_ethdev.c
+++ b/drivers/net/pcap/pcap_ethdev.c
@@ -33,6 +33,7 @@
 #define ETH_PCAP_IFACE_ARG    "iface"
 #define ETH_PCAP_PHY_MAC_ARG  "phy_mac"
 #define ETH_PCAP_INFINITE_RX_ARG  "infinite_rx"
+#define ETH_PCAP_BUF_SIZE_ARG "buf_size"
 
 #define ETH_PCAP_ARG_MAXLEN	64
 
@@ -98,6 +99,7 @@ struct pmd_process_private {
 	pcap_t *rx_pcap[RTE_PMD_PCAP_MAX_QUEUES];
 	pcap_t *tx_pcap[RTE_PMD_PCAP_MAX_QUEUES];
 	pcap_dumper_t *tx_dumper[RTE_PMD_PCAP_MAX_QUEUES];
+	int buf_size;
 };
 
 struct pmd_devargs {
@@ -109,6 +111,7 @@ struct pmd_devargs {
 		const char *type;
 	} queue[RTE_PMD_PCAP_MAX_QUEUES];
 	int phy_mac;
+	int buf_size;
 };
 
 struct pmd_devargs_all {
@@ -131,6 +134,7 @@ static const char *valid_arguments[] = {
 	ETH_PCAP_IFACE_ARG,
 	ETH_PCAP_PHY_MAC_ARG,
 	ETH_PCAP_INFINITE_RX_ARG,
+	ETH_PCAP_BUF_SIZE_ARG,
 	NULL
 };
 
@@ -521,11 +525,46 @@ open_iface_live(const char *iface, pcap_t **pcap) {
 }
 
 static int
-open_single_iface(const char *iface, pcap_t **pcap)
+open_single_iface(const char *iface, int buf_size, pcap_t **pcap)
 {
-	if (open_iface_live(iface, pcap) < 0) {
-		PMD_LOG(ERR, "Couldn't open interface %s", iface);
-		return -1;
+	if (buf_size == 0) {
+		if (open_iface_live(iface, pcap) < 0) {
+			PMD_LOG(ERR, "Couldn't open interface %s", iface);
+			return -1;
+		}
+	} else {
+		pcap_t *p = pcap_create(iface, errbuf);
+		if (p == NULL) {
+			PMD_LOG(ERR, "Couldn't create %s pcap", iface);
+			return -1;
+		}
+
+		if (pcap_set_snaplen(p, RTE_ETH_PCAP_SNAPLEN) < 0) {
+			PMD_LOG(ERR, "Couldn't set %s pcap snaplen", iface);
+			return -1;
+		}
+
+		if (pcap_set_promisc(p, RTE_ETH_PCAP_PROMISC) < 0) {
+			PMD_LOG(ERR, "Couldn't set %s pcap promisc", iface);
+			return -1;
+		}
+
+		if (pcap_set_timeout(p, RTE_ETH_PCAP_TIMEOUT) < 0) {
+			PMD_LOG(ERR, "Couldn't set %s pcap timeout", iface);
+			return -1;
+		}
+
+		if (pcap_set_buffer_size(p, buf_size) < 0) {
+			PMD_LOG(ERR, "Couldn't set %s pcap buffer size(%d)", iface, buf_size);
+			return -1;
+		}
+
+		if (pcap_activate(p) < 0) {
+			PMD_LOG(ERR, "Couldn't activate %s pcap", iface);
+			return -1;
+		}
+
+		*pcap = p;
 	}
 
 	return 0;
@@ -608,7 +647,7 @@ eth_dev_start(struct rte_eth_dev *dev)
 
 		if (!pp->tx_pcap[0] &&
 			strcmp(tx->type, ETH_PCAP_IFACE_ARG) == 0) {
-			if (open_single_iface(tx->name, &pp->tx_pcap[0]) < 0)
+			if (open_single_iface(tx->name, pp->buf_size, &pp->tx_pcap[0]) < 0)
 				return -1;
 			pp->rx_pcap[0] = pp->tx_pcap[0];
 		}
@@ -627,7 +666,7 @@ eth_dev_start(struct rte_eth_dev *dev)
 				return -1;
 		} else if (!pp->tx_pcap[i] &&
 				strcmp(tx->type, ETH_PCAP_TX_IFACE_ARG) == 0) {
-			if (open_single_iface(tx->name, &pp->tx_pcap[i]) < 0)
+			if (open_single_iface(tx->name, pp->buf_size, &pp->tx_pcap[i]) < 0)
 				return -1;
 		}
 	}
@@ -643,7 +682,7 @@ eth_dev_start(struct rte_eth_dev *dev)
 			if (open_single_rx_pcap(rx->name, &pp->rx_pcap[i]) < 0)
 				return -1;
 		} else if (strcmp(rx->type, ETH_PCAP_RX_IFACE_ARG) == 0) {
-			if (open_single_iface(rx->name, &pp->rx_pcap[i]) < 0)
+			if (open_single_iface(rx->name, pp->buf_size, &pp->rx_pcap[i]) < 0)
 				return -1;
 		}
 	}
@@ -1072,7 +1111,7 @@ open_rx_tx_iface(const char *key, const char *value, void *extra_args)
 	struct pmd_devargs *tx = extra_args;
 	pcap_t *pcap = NULL;
 
-	if (open_single_iface(iface, &pcap) < 0)
+	if (open_single_iface(iface, tx->buf_size, &pcap) < 0)
 		return -1;
 
 	tx->queue[0].pcap = pcap;
@@ -1104,7 +1143,7 @@ open_iface(const char *key, const char *value, void *extra_args)
 	struct pmd_devargs *pmd = extra_args;
 	pcap_t *pcap = NULL;
 
-	if (open_single_iface(iface, &pcap) < 0)
+	if (open_single_iface(iface, pmd->buf_size, &pcap) < 0)
 		return -1;
 	if (add_queue(pmd, iface, key, pcap, NULL) < 0) {
 		pcap_close(pcap);
@@ -1154,6 +1193,15 @@ open_tx_iface(const char *key, const char *value, void *extra_args)
 	return open_iface(key, value, extra_args);
 }
 
+static int
+select_buf_size(const char *key __rte_unused, const char *value,
+		void *extra_args)
+{
+	if (extra_args)
+		*(int *)extra_args = atoi(value);
+	return 0;
+}
+
 static int
 select_phy_mac(const char *key __rte_unused, const char *value,
 		void *extra_args)
@@ -1413,6 +1461,13 @@ pmd_pcap_probe(struct rte_vdev_device *dev)
 			return -1;
 	}
 
+	if (rte_kvargs_count(kvlist, ETH_PCAP_BUF_SIZE_ARG) == 1) {
+		ret = rte_kvargs_process(kvlist, ETH_PCAP_BUF_SIZE_ARG,
+				&select_buf_size, &pcaps.buf_size);
+		if (ret < 0)
+			goto free_kvlist;
+	}
+
 	/*
 	 * If iface argument is passed we open the NICs and use them for
 	 * reading / writing
@@ -1456,6 +1511,7 @@ pmd_pcap_probe(struct rte_vdev_device *dev)
 	devargs_all.is_tx_iface =
 		rte_kvargs_count(kvlist, ETH_PCAP_TX_IFACE_ARG) ? 1 : 0;
 	dumpers.num_of_queue = 0;
+	dumpers.buf_size = pcaps.buf_size;
 
 	if (devargs_all.is_rx_pcap) {
 		/*
@@ -1562,6 +1618,7 @@ pmd_pcap_probe(struct rte_vdev_device *dev)
 			pp->tx_dumper[i] = dumpers.queue[i].dumper;
 			pp->tx_pcap[i] = dumpers.queue[i].pcap;
 		}
+		pp->buf_size = pcaps.buf_size;
 
 		eth_dev->process_private = pp;
 		eth_dev->rx_pkt_burst = eth_pcap_rx;
@@ -1618,4 +1675,5 @@ RTE_PMD_REGISTER_PARAM_STRING(net_pcap,
 	ETH_PCAP_TX_IFACE_ARG "=<ifc> "
 	ETH_PCAP_IFACE_ARG "=<ifc> "
 	ETH_PCAP_PHY_MAC_ARG "=<int>"
-	ETH_PCAP_INFINITE_RX_ARG "=<0|1>");
+	ETH_PCAP_INFINITE_RX_ARG "=<0|1>"
+	ETH_PCAP_BUF_SIZE_ARG "=<int>");
-- 
2.30.1.windows.1