From: Laurent Vivier <lviv...@redhat.com>
This commit refactors how the maximum transmit queue size for
virtio-net devices is determined, making the mechanism more generic
and extensible.
Previously, virtio_net_max_tx_queue_size() contained hardcoded
checks for specific network backend types (vhost-user and
vhost-vdpa) to determine their supported maximum queue size. This
created direct dependencies and would require modifications for
every new backend that supports variable queue sizes.
To improve flexibility, a new max_tx_queue_size field is added
to the vhost_net structure. This allows each network backend
to advertise its supported maximum transmit queue size directly.
The virtio_net_max_tx_queue_size() function now retrieves the max
TX queue size from the vhost_net struct, if available and set.
Otherwise, it defaults to VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE.
Signed-off-by: Laurent Vivier <lviv...@redhat.com>
Signed-off-by: Jason Wang <jasow...@redhat.com>
---
hw/net/vhost_net.c | 1 +
hw/net/virtio-net.c | 24 ++++++++++++------------
include/hw/virtio/vhost.h | 1 +
include/net/vhost_net.h | 1 +
net/tap.c | 1 +
net/vhost-user.c | 1 +
net/vhost-vdpa.c | 1 +
7 files changed, 18 insertions(+), 12 deletions(-)
diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
index 976d2b315a..74d2e3ed90 100644
--- a/hw/net/vhost_net.c
+++ b/hw/net/vhost_net.c
@@ -245,6 +245,7 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
net->dev.nvqs = options->nvqs;
net->feature_bits = options->feature_bits;
net->save_acked_features = options->save_acked_features;
+ net->max_tx_queue_size = options->max_tx_queue_size;
net->dev.max_queues = 1;
net->dev.vqs = net->vqs;
diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index e3400f18c8..39fc280839 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -670,22 +670,22 @@ static void virtio_net_set_mrg_rx_bufs(VirtIONet *n, int
mergeable_rx_bufs,
static int virtio_net_max_tx_queue_size(VirtIONet *n)
{
NetClientState *peer = n->nic_conf.peers.ncs[0];
+ struct vhost_net *net;
- /*
- * Backends other than vhost-user or vhost-vdpa don't support max queue
- * size.
- */
if (!peer) {
- return VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE;
+ goto default_value;
}
- switch(peer->info->type) {
- case NET_CLIENT_DRIVER_VHOST_USER:
- case NET_CLIENT_DRIVER_VHOST_VDPA:
- return VIRTQUEUE_MAX_SIZE;
- default:
- return VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE;
- };
+ net = get_vhost_net(peer);
+
+ if (!net || !net->max_tx_queue_size) {
+ goto default_value;
+ }
+
+ return net->max_tx_queue_size;
+
+default_value:
+ return VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE;
}
static int peer_attach(VirtIONet *n, int index)
diff --git a/include/hw/virtio/vhost.h b/include/hw/virtio/vhost.h
index b0830bac79..a62992c819 100644
--- a/include/hw/virtio/vhost.h
+++ b/include/hw/virtio/vhost.h
@@ -145,6 +145,7 @@ struct vhost_net {
struct vhost_virtqueue vqs[2];
int backend;
const int *feature_bits;
+ int max_tx_queue_size;
SaveAcketFeatures *save_acked_features;
NetClientState *nc;
};
diff --git a/include/net/vhost_net.h b/include/net/vhost_net.h
index eb26ed9bdc..8f4fddfb69 100644
--- a/include/net/vhost_net.h
+++ b/include/net/vhost_net.h
@@ -16,6 +16,7 @@ typedef struct VhostNetOptions {
uint32_t busyloop_timeout;
unsigned int nvqs;
const int *feature_bits;
+ int max_tx_queue_size;
GetAckedFeatures *get_acked_features;
SaveAcketFeatures *save_acked_features;
void *opaque;
diff --git a/net/tap.c b/net/tap.c
index 79fa02a65c..2f0cb55c9a 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -746,6 +746,7 @@ static void net_init_tap_one(const NetdevTapOptions *tap,
NetClientState *peer,
options.feature_bits = kernel_feature_bits;
options.get_acked_features = NULL;
options.save_acked_features = NULL;
+ options.max_tx_queue_size = 0;
s->vhost_net = vhost_net_init(&options);
if (!s->vhost_net) {
diff --git a/net/vhost-user.c b/net/vhost-user.c
index 8a3df27b02..bf892915de 100644
--- a/net/vhost-user.c
+++ b/net/vhost-user.c
@@ -138,6 +138,7 @@ static int vhost_user_start(int queues, NetClientState
*ncs[],
options.busyloop_timeout = 0;
options.nvqs = 2;
options.feature_bits = user_feature_bits;
+ options.max_tx_queue_size = VIRTQUEUE_MAX_SIZE;
options.get_acked_features = vhost_user_get_acked_features;
options.save_acked_features = vhost_user_save_acked_features;
diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
index c63225d3d2..353392b3d7 100644
--- a/net/vhost-vdpa.c
+++ b/net/vhost-vdpa.c
@@ -204,6 +204,7 @@ static int vhost_vdpa_add(NetClientState *ncs, void *be,
options.feature_bits = vdpa_feature_bits;
options.get_acked_features = NULL;
options.save_acked_features = NULL;
+ options.max_tx_queue_size = VIRTQUEUE_MAX_SIZE;
net = vhost_net_init(&options);
if (!net) {
--
2.42.0
