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Diffstat (limited to 'hw/net/vhost_net.c')
-rw-r--r--hw/net/vhost_net.c172
1 files changed, 160 insertions, 12 deletions
diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
index 18898af..891f235 100644
--- a/hw/net/vhost_net.c
+++ b/hw/net/vhost_net.c
@@ -48,7 +48,9 @@ static const int kernel_feature_bits[] = {
VIRTIO_F_IOMMU_PLATFORM,
VIRTIO_F_RING_PACKED,
VIRTIO_F_RING_RESET,
+ VIRTIO_F_IN_ORDER,
VIRTIO_F_NOTIFICATION_DATA,
+ VIRTIO_NET_F_RSC_EXT,
VIRTIO_NET_F_HASH_REPORT,
VHOST_INVALID_FEATURE_BIT
};
@@ -78,7 +80,9 @@ static const int user_feature_bits[] = {
VIRTIO_F_IOMMU_PLATFORM,
VIRTIO_F_RING_PACKED,
VIRTIO_F_RING_RESET,
+ VIRTIO_F_IN_ORDER,
VIRTIO_NET_F_RSS,
+ VIRTIO_NET_F_RSC_EXT,
VIRTIO_NET_F_HASH_REPORT,
VIRTIO_NET_F_GUEST_USO4,
VIRTIO_NET_F_GUEST_USO6,
@@ -158,6 +162,148 @@ void vhost_net_save_acked_features(NetClientState *nc)
#endif
}
+static void vhost_net_disable_notifiers_nvhosts(VirtIODevice *dev,
+ NetClientState *ncs, int data_queue_pairs, int nvhosts)
+{
+ VirtIONet *n = VIRTIO_NET(dev);
+ BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(dev)));
+ struct vhost_net *net;
+ struct vhost_dev *hdev;
+ int r, i, j;
+ NetClientState *peer;
+
+ /*
+ * Batch all the host notifiers in a single transaction to avoid
+ * quadratic time complexity in address_space_update_ioeventfds().
+ */
+ memory_region_transaction_begin();
+
+ for (i = 0; i < nvhosts; i++) {
+ if (i < data_queue_pairs) {
+ peer = qemu_get_peer(ncs, i);
+ } else {
+ peer = qemu_get_peer(ncs, n->max_queue_pairs);
+ }
+
+ net = get_vhost_net(peer);
+ hdev = &net->dev;
+ for (j = 0; j < hdev->nvqs; j++) {
+ r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus),
+ hdev->vq_index + j,
+ false);
+ if (r < 0) {
+ error_report("vhost %d VQ %d notifier cleanup failed: %d",
+ i, j, -r);
+ }
+ assert(r >= 0);
+ }
+ }
+ /*
+ * The transaction expects the ioeventfds to be open when it
+ * commits. Do it now, before the cleanup loop.
+ */
+ memory_region_transaction_commit();
+
+ for (i = 0; i < nvhosts; i++) {
+ if (i < data_queue_pairs) {
+ peer = qemu_get_peer(ncs, i);
+ } else {
+ peer = qemu_get_peer(ncs, n->max_queue_pairs);
+ }
+
+ net = get_vhost_net(peer);
+ hdev = &net->dev;
+ for (j = 0; j < hdev->nvqs; j++) {
+ virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus),
+ hdev->vq_index + j);
+ }
+ virtio_device_release_ioeventfd(dev);
+ }
+}
+
+static int vhost_net_enable_notifiers(VirtIODevice *dev,
+ NetClientState *ncs, int data_queue_pairs, int cvq)
+{
+ VirtIONet *n = VIRTIO_NET(dev);
+ BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(dev)));
+ int nvhosts = data_queue_pairs + cvq;
+ struct vhost_net *net;
+ struct vhost_dev *hdev;
+ int r, i, j, k;
+ NetClientState *peer;
+
+ /*
+ * We will pass the notifiers to the kernel, make sure that QEMU
+ * doesn't interfere.
+ */
+ for (i = 0; i < nvhosts; i++) {
+ r = virtio_device_grab_ioeventfd(dev);
+ if (r < 0) {
+ error_report("vhost %d binding does not support host notifiers", i);
+ for (k = 0; k < i; k++) {
+ virtio_device_release_ioeventfd(dev);
+ }
+ return r;
+ }
+ }
+
+ /*
+ * Batch all the host notifiers in a single transaction to avoid
+ * quadratic time complexity in address_space_update_ioeventfds().
+ */
+ memory_region_transaction_begin();
+
+ for (i = 0; i < nvhosts; i++) {
+ if (i < data_queue_pairs) {
+ peer = qemu_get_peer(ncs, i);
+ } else {
+ peer = qemu_get_peer(ncs, n->max_queue_pairs);
+ }
+
+ net = get_vhost_net(peer);
+ hdev = &net->dev;
+
+ for (j = 0; j < hdev->nvqs; j++) {
+ r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus),
+ hdev->vq_index + j,
+ true);
+ if (r < 0) {
+ error_report("vhost %d VQ %d notifier binding failed: %d",
+ i, j, -r);
+ memory_region_transaction_commit();
+ vhost_dev_disable_notifiers_nvqs(hdev, dev, j);
+ goto fail_nvhosts;
+ }
+ }
+ }
+
+ memory_region_transaction_commit();
+
+ return 0;
+fail_nvhosts:
+ vhost_net_disable_notifiers_nvhosts(dev, ncs, data_queue_pairs, i);
+ /*
+ * This for loop starts from i+1, not i, because the i-th ioeventfd
+ * has already been released in vhost_dev_disable_notifiers_nvqs().
+ */
+ for (k = i + 1; k < nvhosts; k++) {
+ virtio_device_release_ioeventfd(dev);
+ }
+
+ return r;
+}
+
+/*
+ * Stop processing guest IO notifications in qemu.
+ * Start processing them in vhost in kernel.
+ */
+static void vhost_net_disable_notifiers(VirtIODevice *dev,
+ NetClientState *ncs, int data_queue_pairs, int cvq)
+{
+ vhost_net_disable_notifiers_nvhosts(dev, ncs, data_queue_pairs,
+ data_queue_pairs + cvq);
+}
+
static int vhost_net_get_fd(NetClientState *backend)
{
switch (backend->info->type) {
@@ -268,11 +414,6 @@ static int vhost_net_start_one(struct vhost_net *net,
}
}
- r = vhost_dev_enable_notifiers(&net->dev, dev);
- if (r < 0) {
- goto fail_notifiers;
- }
-
r = vhost_dev_start(&net->dev, dev, false);
if (r < 0) {
goto fail_start;
@@ -324,8 +465,6 @@ fail:
}
vhost_dev_stop(&net->dev, dev, false);
fail_start:
- vhost_dev_disable_notifiers(&net->dev, dev);
-fail_notifiers:
return r;
}
@@ -347,7 +486,6 @@ static void vhost_net_stop_one(struct vhost_net *net,
if (net->nc->info->stop) {
net->nc->info->stop(net->nc);
}
- vhost_dev_disable_notifiers(&net->dev, dev);
}
int vhost_net_start(VirtIODevice *dev, NetClientState *ncs,
@@ -392,10 +530,16 @@ int vhost_net_start(VirtIODevice *dev, NetClientState *ncs,
}
}
+ r = vhost_net_enable_notifiers(dev, ncs, data_queue_pairs, cvq);
+ if (r < 0) {
+ error_report("Error enabling host notifiers: %d", -r);
+ goto err;
+ }
+
r = k->set_guest_notifiers(qbus->parent, total_notifiers, true);
if (r < 0) {
error_report("Error binding guest notifier: %d", -r);
- goto err;
+ goto err_host_notifiers;
}
for (i = 0; i < nvhosts; i++) {
@@ -410,19 +554,19 @@ int vhost_net_start(VirtIODevice *dev, NetClientState *ncs,
r = vhost_set_vring_enable(peer, peer->vring_enable);
if (r < 0) {
- goto err_start;
+ goto err_guest_notifiers;
}
}
r = vhost_net_start_one(get_vhost_net(peer), dev);
if (r < 0) {
- goto err_start;
+ goto err_guest_notifiers;
}
}
return 0;
-err_start:
+err_guest_notifiers:
while (--i >= 0) {
peer = qemu_get_peer(ncs, i < data_queue_pairs ?
i : n->max_queue_pairs);
@@ -433,6 +577,8 @@ err_start:
fprintf(stderr, "vhost guest notifier cleanup failed: %d\n", e);
fflush(stderr);
}
+err_host_notifiers:
+ vhost_net_disable_notifiers(dev, ncs, data_queue_pairs, cvq);
err:
return r;
}
@@ -464,6 +610,8 @@ void vhost_net_stop(VirtIODevice *dev, NetClientState *ncs,
fflush(stderr);
}
assert(r >= 0);
+
+ vhost_net_disable_notifiers(dev, ncs, data_queue_pairs, cvq);
}
void vhost_net_cleanup(struct vhost_net *net)
generated by cgit v1.1 at 2025-07-01 20:59:01 +0000