From 2857e7850c2a2de02eb9f61c5d760100e382aa09 Mon Sep 17 00:00:00 2001 From: Aloys Augustin Date: Mon, 16 Mar 2020 17:29:52 +0100 Subject: tap: use one tap fd per rx queue This matches vhost queues to linux netdev queues and avoids random packet shuffling across vhost queues on rx. Change-Id: I9901689d361e440fb0b91c9fbaf8124ce525b316 Type: fix Signed-off-by: Aloys Augustin --- src/vnet/devices/tap/tap.c | 92 +++++++++++++++++++++++++++++----------------- 1 file changed, 59 insertions(+), 33 deletions(-) (limited to 'src/vnet/devices/tap') diff --git a/src/vnet/devices/tap/tap.c b/src/vnet/devices/tap/tap.c index 3b67b53de4a..76271dd3f95 100644 --- a/src/vnet/devices/tap/tap.c +++ b/src/vnet/devices/tap/tap.c @@ -111,11 +111,10 @@ tap_free (vlib_main_t * vm, virtio_if_t * vif) virtio_vring_free_tx (vm, vif, TX_QUEUE (i)); /* *INDENT-ON* */ - _IOCTL (vif->tap_fd, TUNSETPERSIST, (void *) (uintptr_t) 0); + _IOCTL (vif->tap_fds[0], TUNSETPERSIST, (void *) (uintptr_t) 0); tap_log_dbg (vif, "TUNSETPERSIST: unset"); error: - if (vif->tap_fd != -1) - close (vif->tap_fd); + vec_foreach_index (i, vif->tap_fds) close (vif->tap_fds[i]); vec_free (vif->vhost_fds); vec_free (vif->rxq_vrings); @@ -140,7 +139,7 @@ tap_create_if (vlib_main_t * vm, tap_create_if_args_t * args) tap_main_t *tm = &tap_main; vnet_sw_interface_t *sw; vnet_hw_interface_t *hw; - int i; + int i, j, num_vhost_queues; int old_netns_fd = -1; struct ifreq ifr = {.ifr_flags = IFF_NO_PI | IFF_VNET_HDR }; struct ifreq get_ifr = {.ifr_flags = 0 }; @@ -149,10 +148,9 @@ tap_create_if (vlib_main_t * vm, tap_create_if_args_t * args) virtio_if_t *vif = 0; clib_error_t *err = 0; unsigned int tap_features; - int tfd, vfd, nfd = -1; + int tfd = -1, qfd = -1, vfd = -1, nfd = -1; char *host_if_name = 0; unsigned int offload = 0; - u16 num_q_pairs; if (args->id != ~0) { @@ -192,8 +190,7 @@ tap_create_if (vlib_main_t * vm, tap_create_if_args_t * args) vif->dev_instance = vif - vim->interfaces; vif->id = args->id; vif->num_txqs = thm->n_vlib_mains; - vif->num_rxqs = args->num_rx_queues; - num_q_pairs = clib_max (vif->num_rxqs, vif->num_txqs); + vif->num_rxqs = clib_max (args->num_rx_queues, 1); if (args->tap_flags & TAP_FLAG_ATTACH) { @@ -228,12 +225,14 @@ tap_create_if (vlib_main_t * vm, tap_create_if_args_t * args) } } } - if ((vif->tap_fd = tfd = open ("/dev/net/tun", O_RDWR | O_NONBLOCK)) < 0) + + if ((tfd = open ("/dev/net/tun", O_RDWR | O_NONBLOCK)) < 0) { args->rv = VNET_API_ERROR_SYSCALL_ERROR_2; args->error = clib_error_return_unix (0, "open '/dev/net/tun'"); goto error; } + vec_add1 (vif->tap_fds, tfd); tap_log_dbg (vif, "open tap fd %d", tfd); _IOCTL (tfd, TUNGETFEATURES, &tap_features); @@ -247,13 +246,13 @@ tap_create_if (vlib_main_t * vm, tap_create_if_args_t * args) if ((tap_features & IFF_MULTI_QUEUE) == 0) { - if (args->num_rx_queues > 1) + if (vif->num_rxqs > 1) { args->rv = VNET_API_ERROR_SYSCALL_ERROR_2; args->error = clib_error_return (0, "multiqueue not supported"); goto error; } - vif->num_rxqs = vif->num_txqs = num_q_pairs = 1; + vif->num_rxqs = vif->num_txqs = 1; } else ifr.ifr_flags |= IFF_MULTI_QUEUE; @@ -282,13 +281,6 @@ tap_create_if (vlib_main_t * vm, tap_create_if_args_t * args) else host_if_name = (char *) args->host_if_name; - if (fcntl (tfd, F_SETFL, O_NONBLOCK) < 0) - { - err = clib_error_return_unix (0, "fcntl(tfd, F_SETFL, O_NONBLOCK)"); - tap_log_err (vif, "set nonblocking: %U", format_clib_error, err); - goto error; - } - /* * unset the persistence when attaching to existing * interface @@ -316,18 +308,48 @@ tap_create_if (vlib_main_t * vm, tap_create_if_args_t * args) } } - tap_log_dbg (vif, "TUNSETVNETHDRSZ: fd %d vnet_hdr_sz %u", tfd, hdrsz); - _IOCTL (tfd, TUNSETVNETHDRSZ, &hdrsz); + /* create additional queues on the linux side. + * we create as many linux queue pairs as we have rx queues + */ + for (i = 1; i < vif->num_rxqs; i++) + { + if ((qfd = open ("/dev/net/tun", O_RDWR | O_NONBLOCK)) < 0) + { + args->rv = VNET_API_ERROR_SYSCALL_ERROR_2; + args->error = clib_error_return_unix (0, "open '/dev/net/tun'"); + goto error; + } + _IOCTL (qfd, TUNSETIFF, (void *) &ifr); + tap_log_dbg (vif, "TUNSETIFF fd %d name %s flags 0x%x", qfd, + ifr.ifr_ifrn.ifrn_name, ifr.ifr_flags); + vec_add1 (vif->tap_fds, qfd); + } + + for (i = 0; i < vif->num_rxqs; i++) + { + tap_log_dbg (vif, "TUNSETVNETHDRSZ: fd %d vnet_hdr_sz %u", + vif->tap_fds[i], hdrsz); + _IOCTL (vif->tap_fds[i], TUNSETVNETHDRSZ, &hdrsz); - i = INT_MAX; - tap_log_dbg (vif, "TUNSETSNDBUF: fd %d sndbuf %d", tfd, i); - _IOCTL (tfd, TUNSETSNDBUF, &i); + j = INT_MAX; + tap_log_dbg (vif, "TUNSETSNDBUF: fd %d sndbuf %d", vif->tap_fds[i], j); + _IOCTL (vif->tap_fds[i], TUNSETSNDBUF, &j); - tap_log_dbg (vif, "TUNSETOFFLOAD: fd %d offload 0x%lx", tfd, offload); - _IOCTL (tfd, TUNSETOFFLOAD, offload); + tap_log_dbg (vif, "TUNSETOFFLOAD: fd %d offload 0x%lx", vif->tap_fds[i], + offload); + _IOCTL (vif->tap_fds[i], TUNSETOFFLOAD, offload); + + if (fcntl (vif->tap_fds[i], F_SETFL, O_NONBLOCK) < 0) + { + err = clib_error_return_unix (0, "fcntl(tfd, F_SETFL, O_NONBLOCK)"); + tap_log_err (vif, "set nonblocking: %U", format_clib_error, err); + goto error; + } + } - /* open vhost-net fd for each queue pair and set ownership */ - for (i = 0; i < num_q_pairs; i++) + /* open as many vhost-net fds as required and set ownership */ + num_vhost_queues = clib_max (vif->num_rxqs, vif->num_txqs); + for (i = 0; i < num_vhost_queues; i++) { if ((vfd = open ("/dev/vhost-net", O_RDWR | O_NONBLOCK)) < 0) { @@ -534,7 +556,7 @@ tap_create_if (vlib_main_t * vm, tap_create_if_args_t * args) } } - for (i = 0; i < num_q_pairs; i++) + for (i = 0; i < num_vhost_queues; i++) { if (i < vif->num_rxqs && (args->error = virtio_vring_init (vm, vif, RX_QUEUE (i), @@ -571,7 +593,7 @@ tap_create_if (vlib_main_t * vm, tap_create_if_args_t * args) vhost_mem->regions[0].userspace_addr); - for (i = 0; i < num_q_pairs; i++) + for (i = 0; i < num_vhost_queues; i++) { int fd = vif->vhost_fds[i]; _IOCTL (fd, VHOST_SET_FEATURES, &vif->features); @@ -582,7 +604,7 @@ tap_create_if (vlib_main_t * vm, tap_create_if_args_t * args) } /* finish initializing queue pair */ - for (i = 0; i < num_q_pairs * 2; i++) + for (i = 0; i < num_vhost_queues * 2; i++) { struct vhost_vring_addr addr = { 0 }; struct vhost_vring_state state = { 0 }; @@ -632,7 +654,7 @@ tap_create_if (vlib_main_t * vm, tap_create_if_args_t * args) fd, file.index, file.fd); _IOCTL (fd, VHOST_SET_VRING_KICK, &file); - file.fd = tfd; + file.fd = vif->tap_fds[qp % vif->num_rxqs]; virtio_log_debug (vif, "VHOST_NET_SET_BACKEND fd %d index %u tap_fd %d", fd, file.index, file.fd); _IOCTL (fd, VHOST_NET_SET_BACKEND, &file); @@ -774,6 +796,7 @@ tap_csum_offload_enable_disable (vlib_main_t * vm, u32 sw_if_index, virtio_if_t *vif; vnet_hw_interface_t *hw; clib_error_t *err = 0; + int i = 0; hw = vnet_get_sup_hw_interface_api_visible_or_null (vnm, sw_if_index); @@ -788,7 +811,8 @@ tap_csum_offload_enable_disable (vlib_main_t * vm, u32 sw_if_index, const unsigned int csum_offload_on = TUN_F_CSUM; const unsigned int csum_offload_off = 0; unsigned int offload = enable_disable ? csum_offload_on : csum_offload_off; - _IOCTL (vif->tap_fd, TUNSETOFFLOAD, offload); + vec_foreach_index (i, vif->tap_fds) + _IOCTL (vif->tap_fds[i], TUNSETOFFLOAD, offload); vif->gso_enabled = 0; vif->csum_offload_enabled = enable_disable ? 1 : 0; @@ -832,6 +856,7 @@ tap_gso_enable_disable (vlib_main_t * vm, u32 sw_if_index, int enable_disable) virtio_if_t *vif; vnet_hw_interface_t *hw; clib_error_t *err = 0; + int i = 0; hw = vnet_get_sup_hw_interface_api_visible_or_null (vnm, sw_if_index); @@ -846,7 +871,8 @@ tap_gso_enable_disable (vlib_main_t * vm, u32 sw_if_index, int enable_disable) const unsigned int gso_on = TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6; const unsigned int gso_off = 0; unsigned int offload = enable_disable ? gso_on : gso_off; - _IOCTL (vif->tap_fd, TUNSETOFFLOAD, offload); + vec_foreach_index (i, vif->tap_fds) + _IOCTL (vif->tap_fds[i], TUNSETOFFLOAD, offload); vif->gso_enabled = enable_disable ? 1 : 0; vif->csum_offload_enabled = 0; if (enable_disable) -- cgit 1.2.3-korg