diff mbox series

net/pcap: create null Rx function

Message ID 20190716093405.23192-1-aideen.mcloughlin@intel.com (mailing list archive)
State Superseded, archived
Delegated to: Ferruh Yigit
Headers show
Series net/pcap: create null Rx function | expand

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/Intel-compilation success Compilation OK

Commit Message

A.McLoughlin July 16, 2019, 9:34 a.m. UTC
Previously in the PCAP PMD it was only possibe to specify an rxq which
uses an iface or a pcap file. This patch creates a 'dummy Rx' function
which is used when no rx_pcap or rx_iface is passed but a tx queue is
passed. This function can be polled and receives no packets.

Signed-off-by: A.McLoughlin <aideen.mcloughlin@intel.com>
---
 drivers/net/pcap/rte_eth_pcap.c | 64 ++++++++++++++++++++++++---------
 1 file changed, 48 insertions(+), 16 deletions(-)

Comments

Ferruh Yigit July 16, 2019, 11:06 a.m. UTC | #1
On 7/16/2019 10:34 AM, A.McLoughlin wrote:
> Previously in the PCAP PMD it was only possibe to specify an rxq which
> uses an iface or a pcap file. This patch creates a 'dummy Rx' function
> which is used when no rx_pcap or rx_iface is passed but a tx queue is
> passed. This function can be polled and receives no packets.

+1 to the feature, thanks.
So user doesn't have to provide both "rx" and "tx" queue anymore, user can only
provide "tx" queue if the intention is just capture Tx packets.

> 
> Signed-off-by: A.McLoughlin <aideen.mcloughlin@intel.com>
> ---
>  drivers/net/pcap/rte_eth_pcap.c | 64 ++++++++++++++++++++++++---------

Can you please update documentation too, 'pcap_ring.rst' to document new
behavior and release notes to announce the feature briefly?

<...>

> +		/* Creating a dummy rx queue for each tx queue passed */
> +		for (i = 0; i < num_tx_queues; i++)
> +			ret =
> +			add_queue(&pcaps, "dummy_rx", "rx_null", NULL, NULL);

Please fix the syntax.

> +	} else {
> +		PMD_LOG(ERR, "Error - No rx or tx queues provided");
> +		exit(0);

We are not allowed to exit/abort in drivers, that is application's discretion,
can you please return error in this case, please remember the cleanup before return.
diff mbox series

Patch

diff --git a/drivers/net/pcap/rte_eth_pcap.c b/drivers/net/pcap/rte_eth_pcap.c
index 26e85183e..348db0e7c 100644
--- a/drivers/net/pcap/rte_eth_pcap.c
+++ b/drivers/net/pcap/rte_eth_pcap.c
@@ -112,6 +112,8 @@  struct pmd_devargs_all {
 	int single_iface;
 	unsigned int is_tx_pcap;
 	unsigned int is_tx_iface;
+	unsigned int is_rx_pcap;
+	unsigned int is_rx_iface;
 	unsigned int infinite_rx;
 };
 
@@ -295,6 +297,14 @@  eth_pcap_rx(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
 	return num_rx;
 }
 
+static uint16_t
+eth_null_rx(void *queue __rte_unused,
+		struct rte_mbuf **bufs __rte_unused,
+		uint16_t nb_pkts __rte_unused)
+{
+	return 0;
+}
+
 static inline void
 calculate_timestamp(struct timeval *ts) {
 	uint64_t cycles;
@@ -1316,8 +1326,10 @@  eth_from_pcaps(struct rte_vdev_device *vdev,
 	/* Assign rx ops. */
 	if (infinite_rx)
 		eth_dev->rx_pkt_burst = eth_pcap_rx_infinite;
-	else
+	else if (devargs_all->is_rx_pcap || devargs_all->is_rx_iface)
 		eth_dev->rx_pkt_burst = eth_pcap_rx;
+	else
+		eth_dev->rx_pkt_burst = eth_null_rx;
 
 	/* Assign tx ops. */
 	if (devargs_all->is_tx_pcap)
@@ -1335,13 +1347,12 @@  static int
 pmd_pcap_probe(struct rte_vdev_device *dev)
 {
 	const char *name;
-	unsigned int is_rx_pcap = 0;
 	struct rte_kvargs *kvlist;
 	struct pmd_devargs pcaps = {0};
 	struct pmd_devargs dumpers = {0};
 	struct rte_eth_dev *eth_dev =  NULL;
 	struct pmd_internals *internal;
-	int ret;
+	int ret = 0;
 
 	struct pmd_devargs_all devargs_all = {
 		.single_iface = 0,
@@ -1404,13 +1415,22 @@  pmd_pcap_probe(struct rte_vdev_device *dev)
 	}
 
 	/*
-	 * We check whether we want to open a RX stream from a real NIC or a
-	 * pcap file
+	 * We check whether we want to open a RX stream from a real NIC, a
+	 * pcap file or open a dummy RX stream
 	 */
-	is_rx_pcap = rte_kvargs_count(kvlist, ETH_PCAP_RX_PCAP_ARG) ? 1 : 0;
+	devargs_all.is_rx_pcap =
+		rte_kvargs_count(kvlist, ETH_PCAP_RX_PCAP_ARG) ? 1 : 0;
+	devargs_all.is_rx_iface =
+		rte_kvargs_count(kvlist, ETH_PCAP_RX_IFACE_ARG) ? 1 : 0;
 	pcaps.num_of_queue = 0;
 
-	if (is_rx_pcap) {
+	devargs_all.is_tx_pcap =
+		rte_kvargs_count(kvlist, ETH_PCAP_TX_PCAP_ARG) ? 1 : 0;
+	devargs_all.is_tx_iface =
+		rte_kvargs_count(kvlist, ETH_PCAP_TX_IFACE_ARG) ? 1 : 0;
+	dumpers.num_of_queue = 0;
+
+	if (devargs_all.is_rx_pcap) {
 		/*
 		 * We check whether we want to infinitely rx the pcap file.
 		 */
@@ -1436,11 +1456,29 @@  pmd_pcap_probe(struct rte_vdev_device *dev)
 
 		ret = rte_kvargs_process(kvlist, ETH_PCAP_RX_PCAP_ARG,
 				&open_rx_pcap, &pcaps);
-	} else {
+	} else if (devargs_all.is_rx_iface) {
 		ret = rte_kvargs_process(kvlist, NULL,
 				&rx_iface_args_process, &pcaps);
-	}
+	} else if (devargs_all.is_tx_iface || devargs_all.is_tx_pcap) {
+		unsigned int i;
 
+		/* Count number of tx queue args passed before dummy rx queue
+		 * creation so a dummy rx queue can be created for each tx queue
+		 */
+		unsigned int num_tx_queues =
+			(rte_kvargs_count(kvlist, ETH_PCAP_TX_PCAP_ARG) +
+			rte_kvargs_count(kvlist, ETH_PCAP_TX_IFACE_ARG));
+
+		PMD_LOG(INFO, "Creating null rx queue since no rx queues were provided.");
+
+		/* Creating a dummy rx queue for each tx queue passed */
+		for (i = 0; i < num_tx_queues; i++)
+			ret =
+			add_queue(&pcaps, "dummy_rx", "rx_null", NULL, NULL);
+	} else {
+		PMD_LOG(ERR, "Error - No rx or tx queues provided");
+		exit(0);
+	}
 	if (ret < 0)
 		goto free_kvlist;
 
@@ -1448,12 +1486,6 @@  pmd_pcap_probe(struct rte_vdev_device *dev)
 	 * We check whether we want to open a TX stream to a real NIC,
 	 * a pcap file, or drop packets on tx
 	 */
-	devargs_all.is_tx_pcap =
-		rte_kvargs_count(kvlist, ETH_PCAP_TX_PCAP_ARG) ? 1 : 0;
-	devargs_all.is_tx_iface =
-		rte_kvargs_count(kvlist, ETH_PCAP_TX_IFACE_ARG) ? 1 : 0;
-	dumpers.num_of_queue = 0;
-
 	if (devargs_all.is_tx_pcap) {
 		ret = rte_kvargs_process(kvlist, ETH_PCAP_TX_PCAP_ARG,
 				&open_tx_pcap, &dumpers);
@@ -1467,7 +1499,7 @@  pmd_pcap_probe(struct rte_vdev_device *dev)
 
 		/* Add 1 dummy queue per rxq which counts and drops packets. */
 		for (i = 0; i < pcaps.num_of_queue; i++)
-			ret = add_queue(&dumpers, "dummy", "tx_drop", NULL,
+			ret = add_queue(&dumpers, "dummy_tx", "tx_drop", NULL,
 					NULL);
 	}