This patch lets vhost support multiqueue. The idea is simple, just launching
multiple threads of vhost and let each of vhost thread processing a subset of
the virtqueues of the device.
The only thing needed is passing a virtqueue index when starting vhost device,
this is used to track the first virtqueue which this vhost thread serves.
Signed-off-by: Jason Wang <jasow...@redhat.com>
---
hw/vhost.c | 52 +++++++++++++++++++++++++++++++++-------------------
hw/vhost.h | 2 ++
hw/vhost_net.c | 7 +++++--
hw/vhost_net.h | 2 +-
hw/virtio-net.c | 3 ++-
5 files changed, 43 insertions(+), 23 deletions(-)
diff --git a/hw/vhost.c b/hw/vhost.c
index 16322a1..63c76d6 100644
--- a/hw/vhost.c
+++ b/hw/vhost.c
@@ -619,11 +619,12 @@ static int vhost_virtqueue_init(struct vhost_dev *dev,
{
hwaddr s, l, a;
int r;
+ int vhost_vq_index = idx % dev->nvqs;
struct vhost_vring_file file = {
- .index = idx,
+ .index = vhost_vq_index
};
struct vhost_vring_state state = {
- .index = idx,
+ .index = vhost_vq_index
};
struct VirtQueue *vvq = virtio_get_queue(vdev, idx);
@@ -669,11 +670,12 @@ static int vhost_virtqueue_init(struct vhost_dev *dev,
goto fail_alloc_ring;
}
- r = vhost_virtqueue_set_addr(dev, vq, idx, dev->log_enabled);
+ r = vhost_virtqueue_set_addr(dev, vq, vhost_vq_index, dev->log_enabled);
if (r < 0) {
r = -errno;
goto fail_alloc;
}
+
file.fd = event_notifier_get_fd(virtio_queue_get_host_notifier(vvq));
r = ioctl(dev->control, VHOST_SET_VRING_KICK, &file);
if (r) {
@@ -714,7 +716,7 @@ static void vhost_virtqueue_cleanup(struct vhost_dev *dev,
unsigned idx)
{
struct vhost_vring_state state = {
- .index = idx,
+ .index = idx % dev->nvqs,
};
int r;
r = ioctl(dev->control, VHOST_GET_VRING_BASE, &state);
@@ -829,7 +831,9 @@ int vhost_dev_enable_notifiers(struct vhost_dev *hdev,
VirtIODevice *vdev)
}
for (i = 0; i < hdev->nvqs; ++i) {
- r = vdev->binding->set_host_notifier(vdev->binding_opaque, i, true);
+ r = vdev->binding->set_host_notifier(vdev->binding_opaque,
+ hdev->vq_index + i,
+ true);
if (r < 0) {
fprintf(stderr, "vhost VQ %d notifier binding failed: %d\n", i,
-r);
goto fail_vq;
@@ -839,7 +843,9 @@ int vhost_dev_enable_notifiers(struct vhost_dev *hdev,
VirtIODevice *vdev)
return 0;
fail_vq:
while (--i >= 0) {
- r = vdev->binding->set_host_notifier(vdev->binding_opaque, i, false);
+ r = vdev->binding->set_host_notifier(vdev->binding_opaque,
+ hdev->vq_index + i,
+ false);
if (r < 0) {
fprintf(stderr, "vhost VQ %d notifier cleanup error: %d\n", i, -r);
fflush(stderr);
@@ -860,7 +866,9 @@ void vhost_dev_disable_notifiers(struct vhost_dev *hdev,
VirtIODevice *vdev)
int i, r;
for (i = 0; i < hdev->nvqs; ++i) {
- r = vdev->binding->set_host_notifier(vdev->binding_opaque, i, false);
+ r = vdev->binding->set_host_notifier(vdev->binding_opaque,
+ hdev->vq_index + i,
+ false);
if (r < 0) {
fprintf(stderr, "vhost VQ %d notifier cleanup failed: %d\n", i,
-r);
fflush(stderr);
@@ -879,10 +887,12 @@ int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice
*vdev)
goto fail;
}
- r = vdev->binding->set_guest_notifiers(vdev->binding_opaque, true);
- if (r < 0) {
- fprintf(stderr, "Error binding guest notifier: %d\n", -r);
- goto fail_notifiers;
+ if (hdev->vq_index == 0) {
+ r = vdev->binding->set_guest_notifiers(vdev->binding_opaque, true);
+ if (r < 0) {
+ fprintf(stderr, "Error binding guest notifier: %d\n", -r);
+ goto fail_notifiers;
+ }
}
r = vhost_dev_set_features(hdev, hdev->log_enabled);
@@ -898,7 +908,7 @@ int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice
*vdev)
r = vhost_virtqueue_init(hdev,
vdev,
hdev->vqs + i,
- i);
+ hdev->vq_index + i);
if (r < 0) {
goto fail_vq;
}
@@ -925,8 +935,9 @@ fail_vq:
vhost_virtqueue_cleanup(hdev,
vdev,
hdev->vqs + i,
- i);
+ hdev->vq_index + i);
}
+ i = hdev->nvqs;
fail_mem:
fail_features:
vdev->binding->set_guest_notifiers(vdev->binding_opaque, false);
@@ -944,21 +955,24 @@ void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice
*vdev)
vhost_virtqueue_cleanup(hdev,
vdev,
hdev->vqs + i,
- i);
+ hdev->vq_index + i);
}
for (i = 0; i < hdev->n_mem_sections; ++i) {
vhost_sync_dirty_bitmap(hdev, &hdev->mem_sections[i],
0, (hwaddr)~0x0ull);
}
- r = vdev->binding->set_guest_notifiers(vdev->binding_opaque, false);
- if (r < 0) {
- fprintf(stderr, "vhost guest notifier cleanup failed: %d\n", r);
- fflush(stderr);
+ if (hdev->vq_index == 0) {
+ r = vdev->binding->set_guest_notifiers(vdev->binding_opaque, false);
+ if (r < 0) {
+ fprintf(stderr, "vhost guest notifier cleanup failed: %d\n", r);
+ fflush(stderr);
+ }
+ assert (r>= 0);
}
- assert (r >= 0);
hdev->started = false;
g_free(hdev->log);
hdev->log = NULL;
hdev->log_size = 0;
}
+
diff --git a/hw/vhost.h b/hw/vhost.h
index 0c47229..e94a9f7 100644
--- a/hw/vhost.h
+++ b/hw/vhost.h
@@ -34,6 +34,8 @@ struct vhost_dev {
MemoryRegionSection *mem_sections;
struct vhost_virtqueue *vqs;
int nvqs;
+ /* the first virtuque which would be used by this vhost dev */
+ int vq_index;
unsigned long long features;
unsigned long long acked_features;
unsigned long long backend_features;
diff --git a/hw/vhost_net.c b/hw/vhost_net.c
index 8241601..cdb294c 100644
--- a/hw/vhost_net.c
+++ b/hw/vhost_net.c
@@ -138,13 +138,15 @@ bool vhost_net_query(VHostNetState *net, VirtIODevice
*dev)
}
int vhost_net_start(struct vhost_net *net,
- VirtIODevice *dev)
+ VirtIODevice *dev,
+ int vq_index)
{
struct vhost_vring_file file = { };
int r;
net->dev.nvqs = 2;
net->dev.vqs = net->vqs;
+ net->dev.vq_index = vq_index;
r = vhost_dev_enable_notifiers(&net->dev, dev);
if (r < 0) {
@@ -214,7 +216,8 @@ bool vhost_net_query(VHostNetState *net, VirtIODevice *dev)
}
int vhost_net_start(struct vhost_net *net,
- VirtIODevice *dev)
+ VirtIODevice *dev,
+ int vq_index)
{
return -ENOSYS;
}
diff --git a/hw/vhost_net.h b/hw/vhost_net.h
index a9db234..c9a8429 100644
--- a/hw/vhost_net.h
+++ b/hw/vhost_net.h
@@ -9,7 +9,7 @@ typedef struct vhost_net VHostNetState;
VHostNetState *vhost_net_init(NetClientState *backend, int devfd, bool force);
bool vhost_net_query(VHostNetState *net, VirtIODevice *dev);
-int vhost_net_start(VHostNetState *net, VirtIODevice *dev);
+int vhost_net_start(VHostNetState *net, VirtIODevice *dev, int vq_index);
void vhost_net_stop(VHostNetState *net, VirtIODevice *dev);
void vhost_net_cleanup(VHostNetState *net);
diff --git a/hw/virtio-net.c b/hw/virtio-net.c
index d57a5a5..70bc0e6 100644
--- a/hw/virtio-net.c
+++ b/hw/virtio-net.c
@@ -126,7 +126,8 @@ static void virtio_net_vhost_status(VirtIONet *n, uint8_t
status)
if (!vhost_net_query(tap_get_vhost_net(qemu_get_queue(n->nic)->peer),
&n->vdev)) {
return;
}
- r = vhost_net_start(tap_get_vhost_net(qemu_get_queue(n->nic)->peer),
&n->vdev);
+ r = vhost_net_start(tap_get_vhost_net(qemu_get_queue(n->nic)->peer),
+ &n->vdev, 0);
if (r < 0) {
error_report("unable to start vhost net: %d: "
"falling back on userspace virtio", -r);
--
1.7.1
--
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