In contrast to other PMDs, the AF_PACKET PMD does not only return incoming but also outgoing packets from rte_eth_rx_burst(). This is fine for applications similar to tcpdump which usually want to see both.
But this is not always the desired behavior. For example, the AF_PACKET PMD might be used in a testing environment in which no regular ethernet PMD is available. In that testing environment, the PMD must behave like a regular one, i.e. not return sent packets from rte_eth_rx_burst(). For this reason, this change adds the ignore_outgoing=<0|1> devarg. When set, the PMD ensures that rte_eth_rx_burst() only returns incoming traffic. The default is 0 so that existing software works as before. Signed-off-by: Frank Dressler <[email protected]> --- .mailmap | 1 + app/test/test_pmd_af_packet.c | 150 ++++++++++++++++++++++ doc/guides/nics/af_packet.rst | 2 + doc/guides/rel_notes/release_26_11.rst | 5 + drivers/net/af_packet/rte_eth_af_packet.c | 25 +++- 5 files changed, 182 insertions(+), 1 deletion(-) diff --git a/.mailmap b/.mailmap index 2e348c3bce..a04fc553d4 100644 --- a/.mailmap +++ b/.mailmap @@ -505,6 +505,7 @@ Francis Kelly <[email protected]> <[email protected]> Francis Racicot <[email protected]> Franck Lenormand <[email protected]> François-Frédéric Ozog <[email protected]> +Frank Dressler <[email protected]> Frank Du <[email protected]> Frank Zhao <[email protected]> Frederico Cadete <[email protected]> diff --git a/app/test/test_pmd_af_packet.c b/app/test/test_pmd_af_packet.c index b668ca5b81..5dd72c35cf 100644 --- a/app/test/test_pmd_af_packet.c +++ b/app/test/test_pmd_af_packet.c @@ -1083,6 +1083,153 @@ test_af_packet_multithread(void) return TEST_SUCCESS; } +/* + * Test: Ignore outgoing configuration + */ +static int +test_af_packet_ignore_outgoing_queues(uint16_t nb_queues, bool ignore_outgoing) +{ + struct rte_mbuf *bufs[BURST_SIZE]; + uint16_t tx_port, rx_port, nb_tx, q; + unsigned int rx_pkts = 0, allocated; + uint64_t elapsed = 0; + const char *err = NULL; + bool have_rx = false; + bool have_tx = false; + char args[128]; + int ret; + + if (!tap_created) { + printf("SKIPPED: TAP interface not available (need root)\n"); + return TEST_SKIPPED; + } + + snprintf(args, sizeof(args), + "iface=%s,qpairs=%u,ignore_outgoing=%u", + TAP_DEV_NAME, nb_queues, ignore_outgoing ? 1 : 0); + ret = create_af_packet_port("net_af_packet_ign_rx", args, &rx_port); + if (ret != 0) { + err = "Failed to create RX af_packet port"; + goto out; + } + have_rx = true; + + /* qdisc_bypass=0 so the kernel TX path sees the TX packets */ + ret = create_af_packet_port("net_af_packet_ign_tx", + "iface=" TAP_DEV_NAME ",qdisc_bypass=0", &tx_port); + if (ret != 0) { + err = "Failed to create TX af_packet port"; + goto out; + } + have_tx = true; + + if (configure_af_packet_port(rx_port, nb_queues, nb_queues) != 0 || + configure_af_packet_port(tx_port, 1, 1) != 0) { + err = "Failed to configure ports"; + goto out; + } + + /* flush the RX port */ + for (q = 0; q < nb_queues; q++) + while (do_rx_burst(rx_port, q, bufs, BURST_SIZE) > 0) + ; + + /* send packets */ + allocated = alloc_tx_mbufs(bufs, 4); + nb_tx = do_tx_burst(tx_port, 0, bufs, allocated); + if (allocated == 0 || nb_tx == 0) { + err = "TX setup failed"; + goto out; + } + + /* receive packets */ + while (elapsed < LOOPBACK_TIMEOUT_US) { + for (q = 0; q < nb_queues; q++) + rx_pkts += do_rx_burst(rx_port, q, bufs, BURST_SIZE); + if (ignore_outgoing) { + if (rx_pkts != 0) + break; + } else if (rx_pkts >= nb_tx) + break; + rte_delay_us_block(STATS_POLL_INTERVAL_US); + elapsed += STATS_POLL_INTERVAL_US; + } + +out: + if (have_tx) { + rte_eth_dev_stop(tx_port); + rte_eth_dev_close(tx_port); + rte_vdev_uninit("net_af_packet_ign_tx"); + } + if (have_rx) { + rte_eth_dev_stop(rx_port); + rte_eth_dev_close(rx_port); + rte_vdev_uninit("net_af_packet_ign_rx"); + } + + TEST_ASSERT(err == NULL, "%s", err); + if (ignore_outgoing) + TEST_ASSERT(rx_pkts == 0, + "ignore_outgoing port with %u queues saw outgoing packets", + nb_queues); + else + TEST_ASSERT(rx_pkts > 0, + "port with %u queues and ignore_outgoing=0 saw no packets", + nb_queues); + + return TEST_SUCCESS; +} + +/* + * Test: invalid ignore_outgoing value + */ +static int +test_af_packet_invalid_ignore_outgoing(void) +{ + int ret; + + if (!tap_created) { + printf("SKIPPED: TAP interface not available (need root)\n"); + return TEST_SKIPPED; + } + + ret = rte_vdev_init("net_af_packet_ign_bad", + "iface=" TAP_DEV_NAME ",ignore_outgoing=2"); + TEST_ASSERT(ret != 0, "Expected failure with ignore_outgoing=2"); + + return TEST_SUCCESS; +} + +/* + * Test: Ignore outgoing for one queue + */ +static int +test_af_packet_ignore_outgoing(void) +{ + int ret; + + ret = test_af_packet_ignore_outgoing_queues(1, true); + if (ret != TEST_SUCCESS) + return ret; + + return test_af_packet_ignore_outgoing_queues(1, false); +} + +/* + * Test: Ignore outgoing for multiple queues + */ +static int +test_af_packet_ignore_outgoing_multi_queue(void) +{ + int ret; + + ret = test_af_packet_ignore_outgoing_queues(2, true); + if (ret != TEST_SUCCESS) + return ret; + + return test_af_packet_ignore_outgoing_queues(2, false); +} + static struct unit_test_suite af_packet_test_suite = { .suite_name = "AF_PACKET PMD Unit Test Suite", .setup = test_af_packet_setup, @@ -1108,6 +1255,9 @@ static struct unit_test_suite af_packet_test_suite = { TEST_CASE(test_af_packet_frame_config), TEST_CASE(test_af_packet_qdisc_bypass), TEST_CASE(test_af_packet_multi_queue), + TEST_CASE(test_af_packet_invalid_ignore_outgoing), + TEST_CASE(test_af_packet_ignore_outgoing), + TEST_CASE(test_af_packet_ignore_outgoing_multi_queue), TEST_CASES_END() /**< NULL terminate unit test array */ } diff --git a/doc/guides/nics/af_packet.rst b/doc/guides/nics/af_packet.rst index 1505b98ff7..fe42180d4e 100644 --- a/doc/guides/nics/af_packet.rst +++ b/doc/guides/nics/af_packet.rst @@ -25,6 +25,8 @@ Some of these, in turn, will be used to configure the PACKET_MMAP settings. disabled by default); * ``fanout_mode`` - set fanout algorithm. Possible choices: hash, lb, cpu, rollover, rnd, qm (optional, default hash); +* ``ignore_outgoing`` - prevent `rte_eth_rx_burst()` from returning transmitted + packets (optional, disabled by default); * ``blocksz`` - PACKET_MMAP block size (optional, default 4096); * ``framesz`` - PACKET_MMAP frame size (optional, default 2048B; Note: multiple of 16B); diff --git a/doc/guides/rel_notes/release_26_11.rst b/doc/guides/rel_notes/release_26_11.rst index 030bd84cea..daf5603a41 100644 --- a/doc/guides/rel_notes/release_26_11.rst +++ b/doc/guides/rel_notes/release_26_11.rst @@ -64,6 +64,11 @@ New Features Added ``rte_vlan_insert_tpid()`` to the net library. +* **Updated AF_PACKET driver.** + + Added ``ignore_outgoing`` vdev argument to prevent `rte_eth_rx_burst()` from + returning transmitted packets. + * **Updated AF_XDP driver.** * Changed the default device plugin endpoint path used when diff --git a/drivers/net/af_packet/rte_eth_af_packet.c b/drivers/net/af_packet/rte_eth_af_packet.c index a93df97023..837da9a3af 100644 --- a/drivers/net/af_packet/rte_eth_af_packet.c +++ b/drivers/net/af_packet/rte_eth_af_packet.c @@ -39,6 +39,7 @@ #define ETH_AF_PACKET_FRAMECOUNT_ARG "framecnt" #define ETH_AF_PACKET_QDISC_BYPASS_ARG "qdisc_bypass" #define ETH_AF_PACKET_FANOUT_MODE_ARG "fanout_mode" +#define ETH_AF_PACKET_IGNORE_OUTGOING_ARG "ignore_outgoing" #define DFLT_FRAME_SIZE (1 << 11) #define DFLT_FRAME_COUNT (1 << 9) @@ -59,6 +60,7 @@ struct __rte_cache_aligned pkt_rx_queue { uint8_t vlan_strip; uint8_t timestamp_offloading; uint8_t scatter_enabled; + uint8_t ignore_outgoing; volatile unsigned long rx_pkts; volatile unsigned long rx_bytes; @@ -103,6 +105,7 @@ static const char *valid_arguments[] = { ETH_AF_PACKET_FRAMECOUNT_ARG, ETH_AF_PACKET_QDISC_BYPASS_ARG, ETH_AF_PACKET_FANOUT_MODE_ARG, + ETH_AF_PACKET_IGNORE_OUTGOING_ARG, NULL }; @@ -166,6 +169,7 @@ eth_af_packet_rx(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts) { unsigned i; struct tpacket2_hdr *ppd; + struct sockaddr_ll *sll; struct rte_mbuf *mbuf; uint8_t *pbuf; struct pkt_rx_queue *pkt_q = queue; @@ -189,6 +193,14 @@ eth_af_packet_rx(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts) if ((ppd->tp_status & TP_STATUS_USER) == 0) break; + /* skip outgoing frames if ignore_outgoing is set */ + if (pkt_q->ignore_outgoing != 0) { + sll = (struct sockaddr_ll *)((uint8_t *)ppd + + TPACKET_ALIGN(sizeof(*ppd))); + if (sll->sll_pkttype == PACKET_OUTGOING) + goto release_frame; + } + /* allocate the next mbuf */ mbuf = rte_pktmbuf_alloc(pkt_q->mb_pool); if (unlikely(mbuf == NULL)) { @@ -877,6 +889,7 @@ rte_pmd_init_internals(struct rte_vdev_device *dev, unsigned int framecnt, unsigned int qdisc_bypass, const char *fanout_mode, + unsigned int ignore_outgoing, struct pmd_internals **internals, struct rte_eth_dev **eth_dev, struct rte_kvargs *kvlist) @@ -1043,6 +1056,7 @@ rte_pmd_init_internals(struct rte_vdev_device *dev, rx_queue = &((*internals)->rx_queue[q]); rx_queue->framecount = req->tp_frame_nr; + rx_queue->ignore_outgoing = ignore_outgoing != 0; rx_queue->map = mmap(NULL, 2 * req->tp_block_size * req->tp_block_nr, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_LOCKED, @@ -1206,6 +1220,7 @@ rte_eth_from_packet(struct rte_vdev_device *dev, unsigned int qpairs = 1; unsigned int qdisc_bypass = 1; const char *fanout_mode = NULL; + unsigned int ignore_outgoing = 0; /* do some parameter checking */ if (*sockfd < 0) @@ -1272,6 +1287,11 @@ rte_eth_from_packet(struct rte_vdev_device *dev, fanout_mode = pair->value; continue; } + if (strstr(pair->key, ETH_AF_PACKET_IGNORE_OUTGOING_ARG) != NULL) { + if (parse_uint(pair->key, pair->value, &ignore_outgoing, 1) < 0) + return -1; + continue; + } } if (framesize > blocksize) { @@ -1298,12 +1318,14 @@ rte_eth_from_packet(struct rte_vdev_device *dev, PMD_LOG(DEBUG, "%s:\tfanout mode %s", name, fanout_mode); else PMD_LOG(DEBUG, "%s:\tfanout mode %s", name, "default PACKET_FANOUT_HASH"); + PMD_LOG(DEBUG, "%s:\tignore outgoing %d", name, ignore_outgoing); if (rte_pmd_init_internals(dev, *sockfd, qpairs, blocksize, blockcount, framesize, framecount, qdisc_bypass, fanout_mode, + ignore_outgoing, &internals, ð_dev, kvlist) < 0) return -1; @@ -1401,4 +1423,5 @@ RTE_PMD_REGISTER_PARAM_STRING(net_af_packet, "framesz=<int> " "framecnt=<int> " "qdisc_bypass=<0|1> " - "fanout_mode=<hash|lb|cpu|rollover|rnd|qm>"); + "fanout_mode=<hash|lb|cpu|rollover|rnd|qm> " + "ignore_outgoing=<0|1>"); -- 2.56.0
