[ovs-dev] [PATCH] Use TPACKET_V1/V2/V3 to accelerate veth for DPDK datapath
William Tu
u9012063 at gmail.com
Wed Jan 22 18:13:42 UTC 2020
On Mon, Jan 20, 2020 at 11:50 PM <yang_y_yi at 163.com> wrote:
>
> From: Yi Yang <yangyi01 at inspur.com>
>
> We can avoid high system call overhead by using TPACKET_V1/V2/V3
> and use DPDK-like poll to receive and send packets (Note: send
> still needs to call sendto to trigger final packet transmission).
>
> I can see about 30% improvement compared to last recvmmsg
> optimization if I use TPACKET_V3. TPACKET_V1/V2 is worse than
> TPACKET_V3, but it still can improve about 20%.
>
> For veth, it is 1.47 Gbps before this patch, it is about 1.98
> Gbps after applied this patch. But it is about 4.00 Gbps if we
> use af_packet for veth, the bottle neck lies in ovs-vswitchd
Hi Yiyang,
I don't understand these three numbers.
Don't you also use af_packet for veth for 1.47 Gbps and 1.98 Gbps?
What's the difference between your 4.00 Gbps and 1.98Gbps?
William
> thread, it will handle too many things for every loop (as below)
> , so it can't work very efficintly as pmd_thread.
>
> memory_run();
> bridge_run();
> unixctl_server_run(unixctl);
> netdev_run();
>
> memory_wait();
> bridge_wait();
> unixctl_server_wait(unixctl);
> netdev_wait();
> poll_block();
>
> In the next step, it will be better if let pmd_thread to handle
> tap and veth interface.
>
> Signed-off-by: Yi Yang <yangyi01 at inspur.com>
> Co-authored-by: William Tu <u9012063 at gmail.com>
> Signed-off-by: William Tu <u9012063 at gmail.com>
> ---
> acinclude.m4 | 23 +++
> configure.ac | 1 +
> lib/netdev-linux-private.h | 27 +++
> lib/netdev-linux.c | 481 ++++++++++++++++++++++++++++++++++++++++++++-
> 4 files changed, 527 insertions(+), 5 deletions(-)
>
> diff --git a/acinclude.m4 b/acinclude.m4
> index c1470cc..e99aff1 100644
> --- a/acinclude.m4
> +++ b/acinclude.m4
> @@ -1095,6 +1095,29 @@ AC_DEFUN([OVS_CHECK_IF_DL],
> AC_SEARCH_LIBS([pcap_open_live], [pcap])
> fi])
>
> +dnl OVS_CHECK_LINUX_TPACKET
> +dnl
> +dnl Configure Linux TPACKET.
> +AC_DEFUN([OVS_CHECK_LINUX_TPACKET], [
> + AC_CHECK_HEADER([linux/if_packet.h],
> + [HAVE_TPACKET=yes],
> + [HAVE_TPACKET=no])
> + AM_CONDITIONAL([HAVE_TPACKET], [test "$HAVE_TPACKET" = yes])
> + if test "$HAVE_TPACKET" = yes; then
> + AC_DEFINE([HAVE_TPACKET], [1],
> + [Define to 1 if linux/if_packet.h is available.])
> + OVS_GREP_IFELSE([/usr/include/linux/if_packet.h], [struct tpacket3_hdr ],
> + [AC_DEFINE([HAVE_TPACKET_V3], [1],
> + [Define to 1 if struct tpacket3_hdr is defined])])
> + OVS_GREP_IFELSE([/usr/include/linux/if_packet.h], [struct tpacket2_hdr ],
> + [AC_DEFINE([HAVE_TPACKET_V2], [1],
> + [Define to 1 if struct tpacket2_hdr is defined])])
> + OVS_GREP_IFELSE([/usr/include/linux/if_packet.h], [struct tpacket_hdr ],
> + [AC_DEFINE([HAVE_TPACKET_V1], [1],
> + [Define to 1 if struct tpacket_hdr is defined])])
> + fi
> +])
> +
> dnl Checks for buggy strtok_r.
> dnl
> dnl Some versions of glibc 2.7 has a bug in strtok_r when compiling
> diff --git a/configure.ac b/configure.ac
> index 4f483fa..51c288b 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -89,6 +89,7 @@ OVS_CHECK_VISUAL_STUDIO_DDK
> OVS_CHECK_COVERAGE
> OVS_CHECK_NDEBUG
> OVS_CHECK_NETLINK
> +OVS_CHECK_LINUX_TPACKET
> OVS_CHECK_OPENSSL
> OVS_CHECK_LIBCAPNG
> OVS_CHECK_LOGDIR
> diff --git a/lib/netdev-linux-private.h b/lib/netdev-linux-private.h
> index 143616c..e8febfe 100644
> --- a/lib/netdev-linux-private.h
> +++ b/lib/netdev-linux-private.h
> @@ -26,6 +26,9 @@
> #include <linux/mii.h>
> #include <stdint.h>
> #include <stdbool.h>
> +#ifdef HAVE_TPACKET
> +#include <linux/if_packet.h>
> +#endif
>
> #include "dp-packet.h"
> #include "netdev-afxdp.h"
> @@ -40,6 +43,25 @@ struct netdev;
>
> #define LINUX_RXQ_TSO_MAX_LEN 65536
>
> +#ifdef HAVE_TPACKET
> +struct tpacket_ring {
> + int sockfd;
> + struct iovec *rd;
> + uint8_t *mm_space;
> + size_t mm_len, rd_len;
> + struct sockaddr_ll ll;
> + int type, rd_num, flen, version;
> + union {
> + struct tpacket_req req;
> + struct tpacket_req3 req3;
> + };
> + uint32_t block_num;
> + uint32_t frame_num;
> + uint32_t frame_num_in_block;
> + void * ppd;
> +};
> +#endif /* HAVE_TPACKET */
> +
> struct netdev_rxq_linux {
> struct netdev_rxq up;
> bool is_tap;
> @@ -103,6 +125,11 @@ struct netdev_linux {
>
> int numa_id; /* NUMA node id. */
>
> +#ifdef HAVE_TPACKET
> + struct tpacket_ring *tp_rx_ring;
> + struct tpacket_ring *tp_tx_ring;
> +#endif
> +
> #ifdef HAVE_AF_XDP
> /* AF_XDP information. */
> struct xsk_socket_info **xsks;
> diff --git a/lib/netdev-linux.c b/lib/netdev-linux.c
> index 6add3e2..b5becf3 100644
> --- a/lib/netdev-linux.c
> +++ b/lib/netdev-linux.c
> @@ -48,6 +48,9 @@
> #include <stdlib.h>
> #include <string.h>
> #include <unistd.h>
> +#ifdef HAVE_TPACKET
> +#include <sys/mman.h>
> +#endif
>
> #include "coverage.h"
> #include "dp-packet.h"
> @@ -153,6 +156,34 @@ struct tpacket_auxdata {
> uint16_t tp_vlan_tpid;
> };
>
> +#ifdef HAVE_TPACKET /* All the definitions for TPACKET */
> +#ifndef __aligned_tpacket
> +# define __aligned_tpacket __attribute__((aligned(TPACKET_ALIGNMENT)))
> +#endif
> +
> +#ifndef __align_tpacket
> +# define __align_tpacket(x) __attribute__((aligned(TPACKET_ALIGN(x))))
> +#endif
> +
> +struct block_desc {
> + uint32_t version;
> + uint32_t offset_to_priv;
> + struct tpacket_hdr_v1 h1;
> +};
> +
> +union frame_map {
> + struct {
> + struct tpacket_hdr tp_h __aligned_tpacket;
> + struct sockaddr_ll s_ll __align_tpacket(sizeof(struct tpacket_hdr));
> + } *v1;
> + struct {
> + struct tpacket2_hdr tp_h __aligned_tpacket;
> + struct sockaddr_ll s_ll __align_tpacket(sizeof(struct tpacket2_hdr));
> + } *v2;
> + void *raw;
> +};
> +#endif /* HAVE_TPACKET */
> +
> /* Linux 2.6.27 introduced ethtool_cmd_speed
> *
> * To avoid revisiting problems reported with using configure to detect
> @@ -1064,6 +1095,141 @@ netdev_linux_rxq_alloc(void)
> return &rx->up;
> }
>
> +#ifdef HAVE_TPACKET
> +static inline int
> +tpacket_set_packet_loss_discard(int sock)
> +{
> + int discard = 1;
> +
> + return setsockopt(sock, SOL_PACKET, PACKET_LOSS, (void *) &discard,
> + sizeof(discard));
> +}
> +
> +static inline void *
> +tpacket_get_next_frame(struct tpacket_ring *ring, uint32_t frame_num)
> +{
> +#ifdef HAVE_TPACKET_V3
> + uint8_t *f0 = ring->rd[0].iov_base;
> +
> + return f0 + (frame_num * ring->req3.tp_frame_size);
> +#else
> + return ring->rd[frame_num].iov_base;
> +#endif
> +}
> +
> +/*
> + * For TPACKET_V1&V2, ring->rd_num is tp_frame_nr, ring->flen is tp_frame_size
> + */
> +static inline void
> +tpacket_v1_v2_fill_ring(struct tpacket_ring *ring, unsigned int blocks)
> +{
> + ring->req.tp_block_size = getpagesize() << 2;
> + ring->req.tp_frame_size = TPACKET_ALIGNMENT << 7;
> + ring->req.tp_block_nr = blocks;
> +
> + ring->req.tp_frame_nr = ring->req.tp_block_size /
> + ring->req.tp_frame_size *
> + ring->req.tp_block_nr;
> +
> + ring->mm_len = ring->req.tp_block_size * ring->req.tp_block_nr;
> + ring->rd_num = ring->req.tp_frame_nr;
> + ring->flen = ring->req.tp_frame_size;
> +}
> +
> +/*
> + * For TPACKET_V3, ring->rd_num is tp_block_nr, ring->flen is tp_block_size
> + */
> +static inline void
> +tpacket_v3_fill_ring(struct tpacket_ring *ring, unsigned int blocks, int type)
> +{
> + if (type == PACKET_RX_RING) {
> + ring->req3.tp_retire_blk_tov = 0;
> + ring->req3.tp_sizeof_priv = 0;
> + ring->req3.tp_feature_req_word = 0;
> + }
> + ring->req3.tp_block_size = getpagesize() << 2;
> + ring->req3.tp_frame_size = TPACKET_ALIGNMENT << 7;
> + ring->req3.tp_block_nr = blocks;
> +
> + ring->req3.tp_frame_nr = ring->req3.tp_block_size /
> + ring->req3.tp_frame_size *
> + ring->req3.tp_block_nr;
> +
> + ring->mm_len = ring->req3.tp_block_size * ring->req3.tp_block_nr;
> + ring->rd_num = ring->req3.tp_block_nr;
> + ring->flen = ring->req3.tp_block_size;
> +}
> +
> +static int
> +tpacket_setup_ring(int sock, struct tpacket_ring *ring, int version, int type)
> +{
> + int ret = 0;
> + unsigned int blocks = 256;
> +
> + ring->type = type;
> + ring->version = version;
> +
> + switch (version) {
> + case TPACKET_V1:
> + case TPACKET_V2:
> + if (type == PACKET_TX_RING) {
> + tpacket_set_packet_loss_discard(sock);
> + }
> + tpacket_v1_v2_fill_ring(ring, blocks);
> + ret = setsockopt(sock, SOL_PACKET, type, &ring->req,
> + sizeof(ring->req));
> + break;
> +
> + case TPACKET_V3:
> + tpacket_v3_fill_ring(ring, blocks, type);
> + ret = setsockopt(sock, SOL_PACKET, type, &ring->req3,
> + sizeof(ring->req3));
> + break;
> + }
> +
> + if (ret == -1) {
> + return -1;
> + }
> +
> + ring->rd_len = ring->rd_num * sizeof(*ring->rd);
> + ring->rd = xmalloc(ring->rd_len);
> + if (ring->rd == NULL) {
> + return -1;
> + }
> +
> + return 0;
> +}
> +
> +static inline int
> +tpacket_mmap_rx_tx_ring(int sock, struct tpacket_ring *rx_ring,
> + struct tpacket_ring *tx_ring)
> +{
> + int i;
> +
> + rx_ring->mm_space = mmap(0, rx_ring->mm_len + tx_ring->mm_len,
> + PROT_READ | PROT_WRITE,
> + MAP_SHARED | MAP_LOCKED | MAP_POPULATE, sock, 0);
> + if (rx_ring->mm_space == MAP_FAILED) {
> + return -1;
> + }
> +
> + memset(rx_ring->rd, 0, rx_ring->rd_len);
> + for (i = 0; i < rx_ring->rd_num; ++i) {
> + rx_ring->rd[i].iov_base = rx_ring->mm_space + (i * rx_ring->flen);
> + rx_ring->rd[i].iov_len = rx_ring->flen;
> + }
> +
> + tx_ring->mm_space = rx_ring->mm_space + rx_ring->mm_len;
> + memset(tx_ring->rd, 0, tx_ring->rd_len);
> + for (i = 0; i < tx_ring->rd_num; ++i) {
> + tx_ring->rd[i].iov_base = tx_ring->mm_space + (i * tx_ring->flen);
> + tx_ring->rd[i].iov_len = tx_ring->flen;
> + }
> +
> + return 0;
> +}
> +#endif
> +
> static int
> netdev_linux_rxq_construct(struct netdev_rxq *rxq_)
> {
> @@ -1079,6 +1245,15 @@ netdev_linux_rxq_construct(struct netdev_rxq *rxq_)
> } else {
> struct sockaddr_ll sll;
> int ifindex, val;
> +#ifdef HAVE_TPACKET
> +#ifdef HAVE_TPACKET_V3
> + int ver = TPACKET_V3;
> +#elif defined(HAVE_TPACKET_V2)
> + int ver = TPACKET_V2;
> +#else
> + int ver = TPACKET_V1;
> +#endif
> +#endif
> /* Result of tcpdump -dd inbound */
> static const struct sock_filter filt[] = {
> { 0x28, 0, 0, 0xfffff004 }, /* ldh [0] */
> @@ -1091,13 +1266,52 @@ netdev_linux_rxq_construct(struct netdev_rxq *rxq_)
> };
>
> /* Create file descriptor. */
> - rx->fd = socket(PF_PACKET, SOCK_RAW, 0);
> + rx->fd = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
> if (rx->fd < 0) {
> error = errno;
> VLOG_ERR("failed to create raw socket (%s)", ovs_strerror(error));
> goto error;
> }
>
> +#ifdef HAVE_TPACKET
> + error = setsockopt(rx->fd, SOL_PACKET, PACKET_VERSION, &ver,
> + sizeof(ver));
> + if (error != 0) {
> + error = errno;
> + VLOG_ERR("%s: failed to set tpacket version (%s)",
> + netdev_get_name(netdev_), ovs_strerror(error));
> + goto error;
> + }
> + netdev->tp_rx_ring = xzalloc(sizeof(struct tpacket_ring));
> + netdev->tp_tx_ring = xzalloc(sizeof(struct tpacket_ring));
> + netdev->tp_rx_ring->sockfd = rx->fd;
> + netdev->tp_tx_ring->sockfd = rx->fd;
> + error = tpacket_setup_ring(rx->fd, netdev->tp_rx_ring, ver,
> + PACKET_RX_RING);
> + if (error != 0) {
> + error = errno;
> + VLOG_ERR("%s: failed to set tpacket rx ring (%s)",
> + netdev_get_name(netdev_), ovs_strerror(error));
> + goto error;
> + }
> + error = tpacket_setup_ring(rx->fd, netdev->tp_tx_ring, ver,
> + PACKET_TX_RING);
> + if (error != 0) {
> + error = errno;
> + VLOG_ERR("%s: failed to set tpacket tx ring (%s)",
> + netdev_get_name(netdev_), ovs_strerror(error));
> + goto error;
> + }
> + error = tpacket_mmap_rx_tx_ring(rx->fd, netdev->tp_rx_ring,
> + netdev->tp_tx_ring);
> + if (error != 0) {
> + error = errno;
> + VLOG_ERR("%s: failed to mmap tpacket rx & tx ring (%s)",
> + netdev_get_name(netdev_), ovs_strerror(error));
> + goto error;
> + }
> +#endif
> +
> val = 1;
> if (setsockopt(rx->fd, SOL_PACKET, PACKET_AUXDATA, &val, sizeof val)) {
> error = errno;
> @@ -1129,7 +1343,12 @@ netdev_linux_rxq_construct(struct netdev_rxq *rxq_)
>
> /* Bind to specific ethernet device. */
> memset(&sll, 0, sizeof sll);
> - sll.sll_family = AF_PACKET;
> + sll.sll_family = PF_PACKET;
> +#ifdef HAVE_TPACKET
> + sll.sll_hatype = 0;
> + sll.sll_pkttype = 0;
> + sll.sll_halen = 0;
> +#endif
> sll.sll_ifindex = ifindex;
> sll.sll_protocol = htons(ETH_P_ALL);
> if (bind(rx->fd, (struct sockaddr *) &sll, sizeof sll) < 0) {
> @@ -1168,6 +1387,17 @@ netdev_linux_rxq_destruct(struct netdev_rxq *rxq_)
> int i;
>
> if (!rx->is_tap) {
> +#ifdef HAVE_TPACKET
> + struct netdev_linux *netdev = netdev_linux_cast(rx->up.netdev);
> +
> + if (netdev->tp_rx_ring) {
> + munmap(netdev->tp_rx_ring->mm_space,
> + 2 * netdev->tp_rx_ring->mm_len);
> + free(netdev->tp_rx_ring->rd);
> + free(netdev->tp_tx_ring->rd);
> + }
> +#endif
> +
> close(rx->fd);
> }
>
> @@ -1184,6 +1414,7 @@ netdev_linux_rxq_dealloc(struct netdev_rxq *rxq_)
> free(rx);
> }
>
> +#ifndef HAVE_TPACKET
> static ovs_be16
> auxdata_to_vlan_tpid(const struct tpacket_auxdata *aux, bool double_tagged)
> {
> @@ -1345,6 +1576,7 @@ netdev_linux_batch_rxq_recv_sock(struct netdev_rxq_linux *rx, int mtu,
> return 0;
> }
>
> +#else /* ifdef HAVE_TPACKET */
> /*
> * Receive packets from tap by batch process for better performance,
> * it can receive NETDEV_MAX_BURST packets at most once, the received
> @@ -1428,6 +1660,125 @@ netdev_linux_batch_rxq_recv_tap(struct netdev_rxq_linux *rx, int mtu,
>
> return 0;
> }
> +static int
> +netdev_linux_batch_recv_tpacket(struct netdev_rxq *rxq_, int mtu,
> + struct dp_packet_batch *batch)
> +{
> + struct netdev_rxq_linux *rx = netdev_rxq_linux_cast(rxq_);
> + struct netdev_linux *netdev = netdev_linux_cast(rx->up.netdev);
> + struct dp_packet *buffer;
> + int i = 0;
> +
> +#ifdef HAVE_TPACKET_V3
> + unsigned int block_num;
> + unsigned int fn_in_block;
> + struct block_desc *pbd;
> + struct tpacket3_hdr *ppd;
> +
> + ppd = (struct tpacket3_hdr *)netdev->tp_rx_ring->ppd;
> + block_num = netdev->tp_rx_ring->block_num;
> + fn_in_block = netdev->tp_rx_ring->frame_num_in_block;
> + pbd = (struct block_desc *) netdev->tp_rx_ring->rd[block_num].iov_base;
> +#else
> +#if defined(HAVE_TPACKET_V2)
> + struct tpacket2_hdr *ppd;
> +#else
> + struct tpacket_hdr *ppd;
> +#endif
> + unsigned int frame_num;
> + unsigned int frame_nr = netdev->tp_rx_ring->rd_num;
> +
> + frame_num = netdev->tp_rx_ring->frame_num;
> +#endif
> +
> + while (i < NETDEV_MAX_BURST) {
> +#ifdef HAVE_TPACKET_V3
> + if ((pbd->h1.block_status & TP_STATUS_USER) == 0) {
> + break;
> + }
> + if (fn_in_block == 0) {
> + ppd = (struct tpacket3_hdr *) ((uint8_t *) pbd +
> + pbd->h1.offset_to_first_pkt);
> + }
> +#elif defined(HAVE_TPACKET_V2)
> + ppd = (struct tpacket2_hdr *)
> + netdev->tp_rx_ring->rd[frame_num].iov_base;
> + if ((ppd->tp_status & TP_STATUS_USER) == 0) {
> + break;
> + }
> +#else
> + ppd = (struct tpacket_hdr *)netdev->tp_rx_ring->rd[frame_num].iov_base;
> + if ((ppd->tp_status & TP_STATUS_USER) == 0) {
> + break;
> + }
> +#endif
> +
> + buffer = dp_packet_new_with_headroom(VLAN_ETH_HEADER_LEN + mtu,
> + DP_NETDEV_HEADROOM);
> + memcpy(dp_packet_data(buffer),
> + (uint8_t *) ppd + ppd->tp_mac, ppd->tp_snaplen);
> + dp_packet_set_size(buffer,
> + dp_packet_size(buffer) + ppd->tp_snaplen);
> +#if defined(HAVE_TPACKET_V2) || defined(HAVE_TPACKET_V3)
> + if (ppd->tp_status & TP_STATUS_VLAN_VALID) {
> + struct eth_header *eth;
> + bool double_tagged;
> + ovs_be16 vlan_tpid;
> +
> + eth = dp_packet_data(buffer);
> + double_tagged = eth->eth_type == htons(ETH_TYPE_VLAN_8021Q);
> + if (ppd->tp_status & TP_STATUS_VLAN_TPID_VALID) {
> +#ifdef HAVE_TPACKET_V3
> + vlan_tpid = htons(ppd->hv1.tp_vlan_tpid);
> +#else
> + vlan_tpid = htons(ppd->tp_vlan_tpid);
> +#endif
> + } else if (double_tagged) {
> + vlan_tpid = htons(ETH_TYPE_VLAN_8021AD);
> + } else {
> + vlan_tpid = htons(ETH_TYPE_VLAN_8021Q);
> + }
> +#ifdef HAVE_TPACKET_V3
> + eth_push_vlan(buffer, vlan_tpid, htons(ppd->hv1.tp_vlan_tci));
> +#else
> + eth_push_vlan(buffer, vlan_tpid, htons(ppd->tp_vlan_tci));
> +#endif
> + }
> +#endif
> + dp_packet_batch_add(batch, buffer);
> +
> +#ifdef HAVE_TPACKET_V3
> + fn_in_block++;
> + if (fn_in_block >= pbd->h1.num_pkts) {
> + pbd->h1.block_status = TP_STATUS_KERNEL;
> + block_num = (block_num + 1) %
> + netdev->tp_rx_ring->req3.tp_block_nr;
> + pbd = (struct block_desc *)
> + netdev->tp_rx_ring->rd[block_num].iov_base;
> + fn_in_block = 0;
> + ppd = NULL;
> + } else {
> + ppd = (struct tpacket3_hdr *)
> + ((uint8_t *) ppd + ppd->tp_next_offset);
> + }
> +#else
> + ppd->tp_status = TP_STATUS_KERNEL;
> + frame_num = (frame_num + 1) % frame_nr;
> +#endif
> + i++;
> + }
> +
> +#ifdef HAVE_TPACKET_V3
> + netdev->tp_rx_ring->block_num = block_num;
> + netdev->tp_rx_ring->frame_num_in_block = fn_in_block;
> + netdev->tp_rx_ring->ppd = ppd;
> +#else
> + netdev->tp_rx_ring->frame_num = frame_num;
> +#endif
> +
> + return 0;
> +}
> +#endif
>
> static int
> netdev_linux_rxq_recv(struct netdev_rxq *rxq_, struct dp_packet_batch *batch,
> @@ -1443,9 +1794,15 @@ netdev_linux_rxq_recv(struct netdev_rxq *rxq_, struct dp_packet_batch *batch,
> }
>
> dp_packet_batch_init(batch);
> - retval = (rx->is_tap
> - ? netdev_linux_batch_rxq_recv_tap(rx, mtu, batch)
> - : netdev_linux_batch_rxq_recv_sock(rx, mtu, batch));
> + if (rx->is_tap) {
> + retval = netdev_linux_batch_rxq_recv_tap(rx, mtu, batch);
> + } else {
> +#ifndef HAVE_TPACKET
> + retval = netdev_linux_batch_rxq_recv_sock(rx, mtu, batch);
> +#else
> + retval = netdev_linux_batch_recv_tpacket(rxq_, mtu, batch);
> +#endif
> + }
>
> if (retval) {
> if (retval != EAGAIN && retval != EMSGSIZE) {
> @@ -1486,6 +1843,7 @@ netdev_linux_rxq_drain(struct netdev_rxq *rxq_)
> }
> }
>
> +#ifndef HAVE_TPACKET
> static int
> netdev_linux_sock_batch_send(int sock, int ifindex, bool tso, int mtu,
> struct dp_packet_batch *batch)
> @@ -1531,6 +1889,7 @@ netdev_linux_sock_batch_send(int sock, int ifindex, bool tso, int mtu,
> return error;
> }
>
> +#else /* ifdef HAVE_TPACKET */
> /* Use the tap fd to send 'batch' to tap device 'netdev'. Using the tap fd is
> * essential, because packets sent to a tap device with an AF_PACKET socket
> * will loop back to be *received* again on the tap device. This doesn't occur
> @@ -1650,6 +2009,114 @@ netdev_linux_get_numa_id(const struct netdev *netdev_)
> return numa_id;
> }
>
> +static inline int
> +tpacket_tx_is_ready(void * next_frame)
> +{
> +#ifdef HAVE_TPACKE_V3
> + struct tpacket3_hdr *hdr = (struct tpacket3_hdr *)next_frame;
> +#elif defined(HAVE_TPACKE_V2)
> + struct tpacket2_hdr *hdr = (struct tpacket2_hdr *)next_frame;
> +#else
> + struct tpacket_hdr *hdr = (struct tpacket_hdr *)next_frame;
> +#endif
> + return !(hdr->tp_status & (TP_STATUS_SEND_REQUEST | TP_STATUS_SENDING));
> +}
> +
> +static int
> +netdev_linux_tpacket_batch_send(struct netdev *netdev_,
> + struct dp_packet_batch *batch)
> +{
> + struct netdev_linux *netdev = netdev_linux_cast(netdev_);
> + struct dp_packet *packet;
> + int sockfd;
> + ssize_t bytes_sent;
> + int total_pkts = 0;
> +
> +#ifdef HAVE_TPACKET_V3
> + unsigned int frame_nr = netdev->tp_tx_ring->req3.tp_frame_nr;
> +#else
> + unsigned int frame_nr = netdev->tp_tx_ring->rd_num;
> +#endif
> + unsigned int frame_num = netdev->tp_tx_ring->frame_num;
> +
> + /* The Linux tap driver returns EIO if the device is not up,
> + * so if the device is not up, don't waste time sending it.
> + * However, if the device is in another network namespace
> + * then OVS can't retrieve the state. In that case, send the
> + * packets anyway. */
> + if (netdev->present && !(netdev->ifi_flags & IFF_UP)) {
> + netdev->tx_dropped += dp_packet_batch_size(batch);
> + return 0;
> + }
> +
> + DP_PACKET_BATCH_FOR_EACH (i, packet, batch) {
> + union frame_map ppd;
> + size_t size = dp_packet_size(packet);
> +#ifdef HAVE_TPACKET_V3
> + struct tpacket3_hdr *next_frame
> + = tpacket_get_next_frame(netdev->tp_tx_ring, frame_num);
> +#elif defined(HAVE_TPACKET_V2)
> + struct tpacket2_hdr *next_frame
> + = tpacket_get_next_frame(netdev->tp_tx_ring, frame_num);
> +#else
> + struct tpacket_hdr *next_frame
> + = tpacket_get_next_frame(netdev->tp_tx_ring, frame_num);
> +#endif
> +
> + ppd.raw = next_frame;
> + if (!tpacket_tx_is_ready(next_frame)) {
> + break;
> + }
> +#ifdef HAVE_TPACKET_V3
> + next_frame->tp_snaplen = size;
> + next_frame->tp_len = size;
> + next_frame->tp_next_offset = 0;
> +
> + memcpy((uint8_t *)ppd.raw + TPACKET3_HDRLEN
> + - sizeof(struct sockaddr_ll),
> + dp_packet_data(packet),
> + size);
> +#elif defined(HAVE_TPACKET_V2)
> + ppd.v2->tp_h.tp_snaplen = size;
> + ppd.v2->tp_h.tp_len = size;
> +
> + memcpy((uint8_t *)ppd.raw + TPACKET2_HDRLEN
> + - sizeof(struct sockaddr_ll),
> + dp_packet_data(packet),
> + size);
> +#else
> + ppd.v1->tp_h.tp_snaplen = size;
> + ppd.v1->tp_h.tp_len = size;
> +
> + memcpy((uint8_t *)ppd.raw + TPACKET_HDRLEN
> + - sizeof(struct sockaddr_ll),
> + dp_packet_data(packet),
> + size);
> +#endif
> + next_frame->tp_status = TP_STATUS_SEND_REQUEST;
> + frame_num = (frame_num + 1) % frame_nr;
> + total_pkts++;
> + }
> + netdev->tp_tx_ring->frame_num = frame_num;
> +
> + /* kick-off transmits */
> + if (total_pkts != 0) {
> + sockfd = netdev->tp_tx_ring->sockfd;
> + bytes_sent = sendto(sockfd, NULL, 0, MSG_DONTWAIT, NULL, 0);
> + if (bytes_sent == -1 &&
> + errno != ENOBUFS && errno != EAGAIN) {
> + /*
> + * In case of an ENOBUFS/EAGAIN error all of the enqueued
> + * packets will be considered successful even though only some
> + * are sent.
> + */
> + netdev->tx_dropped += dp_packet_batch_size(batch);
> + }
> + }
> + return 0;
> +}
> +#endif
> +
> /* Sends 'batch' on 'netdev'. Returns 0 if successful, otherwise a positive
> * errno value. Returns EAGAIN without blocking if the packet cannot be queued
> * immediately. Returns EMSGSIZE if a partial packet was transmitted or if
> @@ -1689,7 +2156,11 @@ netdev_linux_send(struct netdev *netdev_, int qid OVS_UNUSED,
> goto free_batch;
> }
>
> +#ifndef HAVE_TPACKET
> error = netdev_linux_sock_batch_send(sock, ifindex, tso, mtu, batch);
> +#else
> + error = netdev_linux_tpacket_batch_send(netdev_, batch);
> +#endif
> } else {
> error = netdev_linux_tap_batch_send(netdev_, tso, mtu, batch);
> }
> --
> 1.8.3.1
>
>
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