Merge remote-tracking branch 'remotes/jasowang/tags/net-pull-request' into staging

# gpg: Signature made Thu 07 Jul 2016 07:29:44 BST
# gpg:                using RSA key 0xEF04965B398D6211
# gpg: Good signature from "Jason Wang (Jason Wang on RedHat) <jasowang@redhat.com>"
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 215D 46F4 8246 689E C77F  3562 EF04 965B 398D 6211

* remotes/jasowang/tags/net-pull-request:
  tap: vhost busy polling support

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

4 files changed, 49 insertions, 3 deletions

diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
index 50f4dcd655..11fabc0b0a 100644
--- a/hw/net/vhost_net.c
+++ b/hw/net/vhost_net.c
@@ -172,7 +172,7 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
     }
 
     r = vhost_dev_init(&net->dev, options->opaque,
-                       options->backend_type);
+                       options->backend_type, options->busyloop_timeout);
     if (r < 0) {
         goto fail;
     }
diff --git a/hw/scsi/vhost-scsi.c b/hw/scsi/vhost-scsi.c
index 9261d51da7..2a00f2f3c8 100644
--- a/hw/scsi/vhost-scsi.c
+++ b/hw/scsi/vhost-scsi.c
@@ -248,7 +248,7 @@ static void vhost_scsi_realize(DeviceState *dev, Error **errp)
     s->dev.backend_features = 0;
 
     ret = vhost_dev_init(&s->dev, (void *)(uintptr_t)vhostfd,
-                         VHOST_BACKEND_TYPE_KERNEL);
+                         VHOST_BACKEND_TYPE_KERNEL, 0);
     if (ret < 0) {
         error_setg(errp, "vhost-scsi: vhost initialization failed: %s",
                    strerror(-ret));
diff --git a/hw/virtio/vhost-backend.c b/hw/virtio/vhost-backend.c
index b35890289f..d62372e597 100644
--- a/hw/virtio/vhost-backend.c
+++ b/hw/virtio/vhost-backend.c
@@ -138,6 +138,12 @@ static int vhost_kernel_set_vring_call(struct vhost_dev *dev,
     return vhost_kernel_call(dev, VHOST_SET_VRING_CALL, file);
 }
 
+static int vhost_kernel_set_vring_busyloop_timeout(struct vhost_dev *dev,
+                                                   struct vhost_vring_state *s)
+{
+    return vhost_kernel_call(dev, VHOST_SET_VRING_BUSYLOOP_TIMEOUT, s);
+}
+
 static int vhost_kernel_set_features(struct vhost_dev *dev,
                                      uint64_t features)
 {
@@ -185,6 +191,8 @@ static const VhostOps kernel_ops = {
         .vhost_get_vring_base = vhost_kernel_get_vring_base,
         .vhost_set_vring_kick = vhost_kernel_set_vring_kick,
         .vhost_set_vring_call = vhost_kernel_set_vring_call,
+        .vhost_set_vring_busyloop_timeout =
+                                vhost_kernel_set_vring_busyloop_timeout,
         .vhost_set_features = vhost_kernel_set_features,
         .vhost_get_features = vhost_kernel_get_features,
         .vhost_set_owner = vhost_kernel_set_owner,
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index a01394d5ac..ec3abda9d5 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -960,6 +960,28 @@ static void vhost_eventfd_del(MemoryListener *listener,
 {
 }
 
+static int vhost_virtqueue_set_busyloop_timeout(struct vhost_dev *dev,
+                                                int n, uint32_t timeout)
+{
+    int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, n);
+    struct vhost_vring_state state = {
+        .index = vhost_vq_index,
+        .num = timeout,
+    };
+    int r;
+
+    if (!dev->vhost_ops->vhost_set_vring_busyloop_timeout) {
+        return -EINVAL;
+    }
+
+    r = dev->vhost_ops->vhost_set_vring_busyloop_timeout(dev, &state);
+    if (r) {
+        return r;
+    }
+
+    return 0;
+}
+
 static int vhost_virtqueue_init(struct vhost_dev *dev,
                                 struct vhost_virtqueue *vq, int n)
 {
@@ -990,7 +1012,7 @@ static void vhost_virtqueue_cleanup(struct vhost_virtqueue *vq)
 }
 
 int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
-                   VhostBackendType backend_type)
+                   VhostBackendType backend_type, uint32_t busyloop_timeout)
 {
     uint64_t features;
     int i, r;
@@ -1031,6 +1053,17 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
             goto fail_vq;
         }
     }
+
+    if (busyloop_timeout) {
+        for (i = 0; i < hdev->nvqs; ++i) {
+            r = vhost_virtqueue_set_busyloop_timeout(hdev, hdev->vq_index + i,
+                                                     busyloop_timeout);
+            if (r < 0) {
+                goto fail_busyloop;
+            }
+        }
+    }
+
     hdev->features = features;
 
     hdev->memory_listener = (MemoryListener) {
@@ -1073,6 +1106,11 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
     hdev->memory_changed = false;
     memory_listener_register(&hdev->memory_listener, &address_space_memory);
     return 0;
+fail_busyloop:
+    while (--i >= 0) {
+        vhost_virtqueue_set_busyloop_timeout(hdev, hdev->vq_index + i, 0);
+    }
+    i = hdev->nvqs;
 fail_vq:
     while (--i >= 0) {
         vhost_virtqueue_cleanup(hdev->vqs + i);