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 <aloaugus@cisco.com>
diff --git a/src/vnet/devices/tap/tap.c b/src/vnet/devices/tap/tap.c
index 3b67b53..76271dd 100644
--- a/src/vnet/devices/tap/tap.c
+++ b/src/vnet/devices/tap/tap.c
@@ -111,11 +111,10 @@
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_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 @@
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 @@
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 @@
}
}
}
- 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 @@
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 @@
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_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);
+ }
- i = INT_MAX;
- tap_log_dbg (vif, "TUNSETSNDBUF: fd %d sndbuf %d", tfd, i);
- _IOCTL (tfd, TUNSETSNDBUF, &i);
+ 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);
- tap_log_dbg (vif, "TUNSETOFFLOAD: fd %d offload 0x%lx", tfd, offload);
- _IOCTL (tfd, TUNSETOFFLOAD, offload);
+ j = INT_MAX;
+ tap_log_dbg (vif, "TUNSETSNDBUF: fd %d sndbuf %d", vif->tap_fds[i], j);
+ _IOCTL (vif->tap_fds[i], TUNSETSNDBUF, &j);
- /* open vhost-net fd for each queue pair and set ownership */
- for (i = 0; i < num_q_pairs; i++)
+ 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 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 @@
}
}
- 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 @@
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 @@
}
/* 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 @@
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 @@
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 @@
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 @@
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 @@
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)
diff --git a/src/vnet/devices/virtio/virtio.c b/src/vnet/devices/virtio/virtio.c
index 00a588a..858105c 100644
--- a/src/vnet/devices/virtio/virtio.c
+++ b/src/vnet/devices/virtio/virtio.c
@@ -312,7 +312,10 @@
str = format (str, " %d", vif->vhost_fds[i]);
vlib_cli_output (vm, " vhost-fds%v", str);
vec_free (str);
- vlib_cli_output (vm, " tap-fd %d", vif->tap_fd);
+ vec_foreach_index (i, vif->tap_fds)
+ str = format (str, " %d", vif->tap_fds[i]);
+ vlib_cli_output (vm, " tap-fds%v", str);
+ vec_free (str);
}
vlib_cli_output (vm, " gso-enabled %d", vif->gso_enabled);
vlib_cli_output (vm, " csum-enabled %d", vif->csum_offload_enabled);
diff --git a/src/vnet/devices/virtio/virtio.h b/src/vnet/devices/virtio/virtio.h
index 3e8f941..3151c50 100644
--- a/src/vnet/devices/virtio/virtio.h
+++ b/src/vnet/devices/virtio/virtio.h
@@ -156,7 +156,7 @@
};
u32 per_interface_next_index;
int *vhost_fds;
- int tap_fd;
+ int *tap_fds;
u32 msix_enabled;
u32 pci_dev_handle;
virtio_vring_t *rxq_vrings;