diff mbox

Avoid additional GET_FEATURES call on vhost-user

Message ID 1471596663-31298-1-git-send-email-felipe@nutanix.com (mailing list archive)
State New, archived
Headers show

Commit Message

Felipe Franciosi Aug. 19, 2016, 8:51 a.m. UTC
Vhost-user requires an early GET_FEATURES call to determine if the
slave supports protocol feature negotiation. An extra GET_FEATURES
call is made after vhost_backend_init() to actually set the device
features.

This patch moves the actual setting of the device features to both
implementations (kernel/user) of vhost_backend_init(), therefore
eliminating the need for a second call.

Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
---
 hw/virtio/vhost-backend.c | 27 ++++++++++++++++++---------
 hw/virtio/vhost-user.c    |  1 +
 hw/virtio/vhost.c         |  9 ---------
 3 files changed, 19 insertions(+), 18 deletions(-)

Comments

Marc-André Lureau Aug. 25, 2016, 11:14 a.m. UTC | #1
Hi

On Sat, Aug 20, 2016 at 3:28 AM Felipe Franciosi <felipe@nutanix.com> wrote:

> Vhost-user requires an early GET_FEATURES call to determine if the
> slave supports protocol feature negotiation. An extra GET_FEATURES
> call is made after vhost_backend_init() to actually set the device
> features.
>
> This patch moves the actual setting of the device features to both
> implementations (kernel/user) of vhost_backend_init(), therefore
> eliminating the need for a second call.
>
> Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
>


Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>


> ---
>  hw/virtio/vhost-backend.c | 27 ++++++++++++++++++---------
>  hw/virtio/vhost-user.c    |  1 +
>  hw/virtio/vhost.c         |  9 ---------
>  3 files changed, 19 insertions(+), 18 deletions(-)
>
> diff --git a/hw/virtio/vhost-backend.c b/hw/virtio/vhost-backend.c
> index 7681f15..a519fe2 100644
> --- a/hw/virtio/vhost-backend.c
> +++ b/hw/virtio/vhost-backend.c
> @@ -25,15 +25,6 @@ static int vhost_kernel_call(struct vhost_dev *dev,
> unsigned long int request,
>      return ioctl(fd, request, arg);
>  }
>
> -static int vhost_kernel_init(struct vhost_dev *dev, void *opaque)
> -{
> -    assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL);
> -
> -    dev->opaque = opaque;
> -
> -    return 0;
> -}
> -
>  static int vhost_kernel_cleanup(struct vhost_dev *dev)
>  {
>      int fd = (uintptr_t) dev->opaque;
> @@ -172,6 +163,24 @@ static int vhost_kernel_get_vq_index(struct vhost_dev
> *dev, int idx)
>      return idx - dev->vq_index;
>  }
>
> +static int vhost_kernel_init(struct vhost_dev *dev, void *opaque)
> +{
> +    uint64_t features;
> +    int r;
> +
> +    assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL);
> +
> +    dev->opaque = opaque;
> +
> +    r = vhost_kernel_get_features(dev, &features);
> +    if (r < 0) {
> +        return r;
> +    }
> +    dev->features = features;
> +
> +    return 0;
> +}
> +
>  static const VhostOps kernel_ops = {
>          .backend_type = VHOST_BACKEND_TYPE_KERNEL,
>          .vhost_backend_init = vhost_kernel_init,
> diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
> index b57454a..684f6d7 100644
> --- a/hw/virtio/vhost-user.c
> +++ b/hw/virtio/vhost-user.c
> @@ -578,6 +578,7 @@ static int vhost_user_init(struct vhost_dev *dev, void
> *opaque)
>      if (err < 0) {
>          return err;
>      }
> +    dev->features = features;
>
>      if (virtio_has_feature(features, VHOST_USER_F_PROTOCOL_FEATURES)) {
>          dev->backend_features |= 1ULL << VHOST_USER_F_PROTOCOL_FEATURES;
> diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
> index 3d0c807..cb9870a 100644
> --- a/hw/virtio/vhost.c
> +++ b/hw/virtio/vhost.c
> @@ -1037,7 +1037,6 @@ static void vhost_virtqueue_cleanup(struct
> vhost_virtqueue *vq)
>  int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
>                     VhostBackendType backend_type, uint32_t
> busyloop_timeout)
>  {
> -    uint64_t features;
>      int i, r, n_initialized_vqs = 0;
>
>      hdev->migration_blocker = NULL;
> @@ -1063,12 +1062,6 @@ int vhost_dev_init(struct vhost_dev *hdev, void
> *opaque,
>          goto fail;
>      }
>
> -    r = hdev->vhost_ops->vhost_get_features(hdev, &features);
> -    if (r < 0) {
> -        VHOST_OPS_DEBUG("vhost_get_features failed");
> -        goto fail;
> -    }
> -
>      for (i = 0; i < hdev->nvqs; ++i, ++n_initialized_vqs) {
>          r = vhost_virtqueue_init(hdev, hdev->vqs + i, hdev->vq_index + i);
>          if (r < 0) {
> @@ -1086,8 +1079,6 @@ int vhost_dev_init(struct vhost_dev *hdev, void
> *opaque,
>          }
>      }
>
> -    hdev->features = features;
> -
>      hdev->memory_listener = (MemoryListener) {
>          .begin = vhost_begin,
>          .commit = vhost_commit,
> --
> 1.9.5
>
>
> --
Marc-André Lureau
Michael S. Tsirkin Sept. 19, 2016, 5:42 p.m. UTC | #2
Thanks for the reminder. 2.8 is open now so I can integrate this.
I would appreciate it if you could rebase this top of

	commit d1b4259f1ab18af24e6a297edb6a8f71691f3256
	Author: Maxime Coquelin <maxime.coquelin@redhat.com>
	Date:   Tue Sep 13 15:30:30 2016 +0200
	    virtio-bus: Plug devices after features are negotiated

test and repost if it still works.

Thanks!


On Mon, Sep 19, 2016 at 05:25:49PM +0000, Felipe Franciosi wrote:
> Gentle ping.
> 
>  
> 
> Thanks,
> 
> Felipe
> 
>  
> 
> From: Marc-André Lureau <marcandre.lureau@gmail.com>
> Date: Thursday, 25 August 2016 at 12:14
> To: Felipe Franciosi <felipe@nutanix.com>, "qemu-devel@nongnu.org"
> <qemu-devel@nongnu.org>, "Michael S. Tsirkin" <mst@redhat.com>
> Subject: Re: [Qemu-devel] [PATCH] Avoid additional GET_FEATURES call on
> vhost-user
> 
>  
> 
>     Hi
> 
>      
> 
>     On Sat, Aug 20, 2016 at 3:28 AM Felipe Franciosi <felipe@nutanix.com>
>     wrote:
> 
>         Vhost-user requires an early GET_FEATURES call to determine if the
>         slave supports protocol feature negotiation. An extra GET_FEATURES
>         call is made after vhost_backend_init() to actually set the device
>         features.
> 
>         This patch moves the actual setting of the device features to both
>         implementations (kernel/user) of vhost_backend_init(), therefore
>         eliminating the need for a second call.
> 
>         Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
> 
> 
> 
>     Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> 
>      
> 
>         ---
>          hw/virtio/vhost-backend.c | 27 ++++++++++++++++++---------
>          hw/virtio/vhost-user.c    |  1 +
>          hw/virtio/vhost.c         |  9 ---------
>          3 files changed, 19 insertions(+), 18 deletions(-)
> 
>         diff --git a/hw/virtio/vhost-backend.c b/hw/virtio/vhost-backend.c
>         index 7681f15..a519fe2 100644
>         --- a/hw/virtio/vhost-backend.c
>         +++ b/hw/virtio/vhost-backend.c
>         @@ -25,15 +25,6 @@ static int vhost_kernel_call(struct vhost_dev *dev,
>         unsigned long int request,
>              return ioctl(fd, request, arg);
>          }
> 
>         -static int vhost_kernel_init(struct vhost_dev *dev, void *opaque)
>         -{
>         -    assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL);
>         -
>         -    dev->opaque = opaque;
>         -
>         -    return 0;
>         -}
>         -
>          static int vhost_kernel_cleanup(struct vhost_dev *dev)
>          {
>              int fd = (uintptr_t) dev->opaque;
>         @@ -172,6 +163,24 @@ static int vhost_kernel_get_vq_index(struct
>         vhost_dev *dev, int idx)
>              return idx - dev->vq_index;
>          }
> 
>         +static int vhost_kernel_init(struct vhost_dev *dev, void *opaque)
>         +{
>         +    uint64_t features;
>         +    int r;
>         +
>         +    assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL);
>         +
>         +    dev->opaque = opaque;
>         +
>         +    r = vhost_kernel_get_features(dev, &features);
>         +    if (r < 0) {
>         +        return r;
>         +    }
>         +    dev->features = features;
>         +
>         +    return 0;
>         +}
>         +
>          static const VhostOps kernel_ops = {
>                  .backend_type = VHOST_BACKEND_TYPE_KERNEL,
>                  .vhost_backend_init = vhost_kernel_init,
>         diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
>         index b57454a..684f6d7 100644
>         --- a/hw/virtio/vhost-user.c
>         +++ b/hw/virtio/vhost-user.c
>         @@ -578,6 +578,7 @@ static int vhost_user_init(struct vhost_dev *dev,
>         void *opaque)
>              if (err < 0) {
>                  return err;
>              }
>         +    dev->features = features;
> 
>              if (virtio_has_feature(features, VHOST_USER_F_PROTOCOL_FEATURES))
>         {
>                  dev->backend_features |= 1ULL <<
>         VHOST_USER_F_PROTOCOL_FEATURES;
>         diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
>         index 3d0c807..cb9870a 100644
>         --- a/hw/virtio/vhost.c
>         +++ b/hw/virtio/vhost.c
>         @@ -1037,7 +1037,6 @@ static void vhost_virtqueue_cleanup(struct
>         vhost_virtqueue *vq)
>          int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
>                             VhostBackendType backend_type, uint32_t
>         busyloop_timeout)
>          {
>         -    uint64_t features;
>              int i, r, n_initialized_vqs = 0;
> 
>              hdev->migration_blocker = NULL;
>         @@ -1063,12 +1062,6 @@ int vhost_dev_init(struct vhost_dev *hdev, void
>         *opaque,
>                  goto fail;
>              }
> 
>         -    r = hdev->vhost_ops->vhost_get_features(hdev, &features);
>         -    if (r < 0) {
>         -        VHOST_OPS_DEBUG("vhost_get_features failed");
>         -        goto fail;
>         -    }
>         -
>              for (i = 0; i < hdev->nvqs; ++i, ++n_initialized_vqs) {
>                  r = vhost_virtqueue_init(hdev, hdev->vqs + i, hdev->vq_index +
>         i);
>                  if (r < 0) {
>         @@ -1086,8 +1079,6 @@ int vhost_dev_init(struct vhost_dev *hdev, void
>         *opaque,
>                  }
>              }
> 
>         -    hdev->features = features;
>         -
>              hdev->memory_listener = (MemoryListener) {
>                  .begin = vhost_begin,
>                  .commit = vhost_commit,
>         --
>         1.9.5
> 
> 
>     --
> 
>     Marc-André Lureau
>
Felipe Franciosi Sept. 22, 2016, 1:22 p.m. UTC | #3
> On 19 Sep 2016, at 18:42, Michael S. Tsirkin <mst@redhat.com> wrote:
> 
> Thanks for the reminder. 2.8 is open now so I can integrate this.
> I would appreciate it if you could rebase this top of
> 
> 	commit d1b4259f1ab18af24e6a297edb6a8f71691f3256
> 	Author: Maxime Coquelin <maxime.coquelin@redhat.com>
> 	Date:   Tue Sep 13 15:30:30 2016 +0200
> 	    virtio-bus: Plug devices after features are negotiated
> 
> test and repost if it still works.
> 
> Thanks!

No problem! Done! :)

http://lists.nongnu.org/archive/html/qemu-devel/2016-09/msg05582.html

Felipe

> 
> 
> On Mon, Sep 19, 2016 at 05:25:49PM +0000, Felipe Franciosi wrote:
>> Gentle ping.
>> 
>> 
>> 
>> Thanks,
>> 
>> Felipe
>> 
>> 
>> 
>> From: Marc-André Lureau <marcandre.lureau@gmail.com>
>> Date: Thursday, 25 August 2016 at 12:14
>> To: Felipe Franciosi <felipe@nutanix.com>, "qemu-devel@nongnu.org"
>> <qemu-devel@nongnu.org>, "Michael S. Tsirkin" <mst@redhat.com>
>> Subject: Re: [Qemu-devel] [PATCH] Avoid additional GET_FEATURES call on
>> vhost-user
>> 
>> 
>> 
>>    Hi
>> 
>> 
>> 
>>    On Sat, Aug 20, 2016 at 3:28 AM Felipe Franciosi <felipe@nutanix.com>
>>    wrote:
>> 
>>        Vhost-user requires an early GET_FEATURES call to determine if the
>>        slave supports protocol feature negotiation. An extra GET_FEATURES
>>        call is made after vhost_backend_init() to actually set the device
>>        features.
>> 
>>        This patch moves the actual setting of the device features to both
>>        implementations (kernel/user) of vhost_backend_init(), therefore
>>        eliminating the need for a second call.
>> 
>>        Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
>> 
>> 
>> 
>>    Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
>> 
>> 
>> 
>>        ---
>>         hw/virtio/vhost-backend.c | 27 ++++++++++++++++++---------
>>         hw/virtio/vhost-user.c    |  1 +
>>         hw/virtio/vhost.c         |  9 ---------
>>         3 files changed, 19 insertions(+), 18 deletions(-)
>> 
>>        diff --git a/hw/virtio/vhost-backend.c b/hw/virtio/vhost-backend.c
>>        index 7681f15..a519fe2 100644
>>        --- a/hw/virtio/vhost-backend.c
>>        +++ b/hw/virtio/vhost-backend.c
>>        @@ -25,15 +25,6 @@ static int vhost_kernel_call(struct vhost_dev *dev,
>>        unsigned long int request,
>>             return ioctl(fd, request, arg);
>>         }
>> 
>>        -static int vhost_kernel_init(struct vhost_dev *dev, void *opaque)
>>        -{
>>        -    assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL);
>>        -
>>        -    dev->opaque = opaque;
>>        -
>>        -    return 0;
>>        -}
>>        -
>>         static int vhost_kernel_cleanup(struct vhost_dev *dev)
>>         {
>>             int fd = (uintptr_t) dev->opaque;
>>        @@ -172,6 +163,24 @@ static int vhost_kernel_get_vq_index(struct
>>        vhost_dev *dev, int idx)
>>             return idx - dev->vq_index;
>>         }
>> 
>>        +static int vhost_kernel_init(struct vhost_dev *dev, void *opaque)
>>        +{
>>        +    uint64_t features;
>>        +    int r;
>>        +
>>        +    assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL);
>>        +
>>        +    dev->opaque = opaque;
>>        +
>>        +    r = vhost_kernel_get_features(dev, &features);
>>        +    if (r < 0) {
>>        +        return r;
>>        +    }
>>        +    dev->features = features;
>>        +
>>        +    return 0;
>>        +}
>>        +
>>         static const VhostOps kernel_ops = {
>>                 .backend_type = VHOST_BACKEND_TYPE_KERNEL,
>>                 .vhost_backend_init = vhost_kernel_init,
>>        diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
>>        index b57454a..684f6d7 100644
>>        --- a/hw/virtio/vhost-user.c
>>        +++ b/hw/virtio/vhost-user.c
>>        @@ -578,6 +578,7 @@ static int vhost_user_init(struct vhost_dev *dev,
>>        void *opaque)
>>             if (err < 0) {
>>                 return err;
>>             }
>>        +    dev->features = features;
>> 
>>             if (virtio_has_feature(features, VHOST_USER_F_PROTOCOL_FEATURES))
>>        {
>>                 dev->backend_features |= 1ULL <<
>>        VHOST_USER_F_PROTOCOL_FEATURES;
>>        diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
>>        index 3d0c807..cb9870a 100644
>>        --- a/hw/virtio/vhost.c
>>        +++ b/hw/virtio/vhost.c
>>        @@ -1037,7 +1037,6 @@ static void vhost_virtqueue_cleanup(struct
>>        vhost_virtqueue *vq)
>>         int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
>>                            VhostBackendType backend_type, uint32_t
>>        busyloop_timeout)
>>         {
>>        -    uint64_t features;
>>             int i, r, n_initialized_vqs = 0;
>> 
>>             hdev->migration_blocker = NULL;
>>        @@ -1063,12 +1062,6 @@ int vhost_dev_init(struct vhost_dev *hdev, void
>>        *opaque,
>>                 goto fail;
>>             }
>> 
>>        -    r = hdev->vhost_ops->vhost_get_features(hdev, &features);
>>        -    if (r < 0) {
>>        -        VHOST_OPS_DEBUG("vhost_get_features failed");
>>        -        goto fail;
>>        -    }
>>        -
>>             for (i = 0; i < hdev->nvqs; ++i, ++n_initialized_vqs) {
>>                 r = vhost_virtqueue_init(hdev, hdev->vqs + i, hdev->vq_index +
>>        i);
>>                 if (r < 0) {
>>        @@ -1086,8 +1079,6 @@ int vhost_dev_init(struct vhost_dev *hdev, void
>>        *opaque,
>>                 }
>>             }
>> 
>>        -    hdev->features = features;
>>        -
>>             hdev->memory_listener = (MemoryListener) {
>>                 .begin = vhost_begin,
>>                 .commit = vhost_commit,
>>        --
>>        1.9.5
>> 
>> 
>>    --
>> 
>>    Marc-André Lureau
>>
diff mbox

Patch

diff --git a/hw/virtio/vhost-backend.c b/hw/virtio/vhost-backend.c
index 7681f15..a519fe2 100644
--- a/hw/virtio/vhost-backend.c
+++ b/hw/virtio/vhost-backend.c
@@ -25,15 +25,6 @@  static int vhost_kernel_call(struct vhost_dev *dev, unsigned long int request,
     return ioctl(fd, request, arg);
 }
 
-static int vhost_kernel_init(struct vhost_dev *dev, void *opaque)
-{
-    assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL);
-
-    dev->opaque = opaque;
-
-    return 0;
-}
-
 static int vhost_kernel_cleanup(struct vhost_dev *dev)
 {
     int fd = (uintptr_t) dev->opaque;
@@ -172,6 +163,24 @@  static int vhost_kernel_get_vq_index(struct vhost_dev *dev, int idx)
     return idx - dev->vq_index;
 }
 
+static int vhost_kernel_init(struct vhost_dev *dev, void *opaque)
+{
+    uint64_t features;
+    int r;
+
+    assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL);
+
+    dev->opaque = opaque;
+
+    r = vhost_kernel_get_features(dev, &features);
+    if (r < 0) {
+        return r;
+    }
+    dev->features = features;
+
+    return 0;
+}
+
 static const VhostOps kernel_ops = {
         .backend_type = VHOST_BACKEND_TYPE_KERNEL,
         .vhost_backend_init = vhost_kernel_init,
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index b57454a..684f6d7 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -578,6 +578,7 @@  static int vhost_user_init(struct vhost_dev *dev, void *opaque)
     if (err < 0) {
         return err;
     }
+    dev->features = features;
 
     if (virtio_has_feature(features, VHOST_USER_F_PROTOCOL_FEATURES)) {
         dev->backend_features |= 1ULL << VHOST_USER_F_PROTOCOL_FEATURES;
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index 3d0c807..cb9870a 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -1037,7 +1037,6 @@  static void vhost_virtqueue_cleanup(struct vhost_virtqueue *vq)
 int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
                    VhostBackendType backend_type, uint32_t busyloop_timeout)
 {
-    uint64_t features;
     int i, r, n_initialized_vqs = 0;
 
     hdev->migration_blocker = NULL;
@@ -1063,12 +1062,6 @@  int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
         goto fail;
     }
 
-    r = hdev->vhost_ops->vhost_get_features(hdev, &features);
-    if (r < 0) {
-        VHOST_OPS_DEBUG("vhost_get_features failed");
-        goto fail;
-    }
-
     for (i = 0; i < hdev->nvqs; ++i, ++n_initialized_vqs) {
         r = vhost_virtqueue_init(hdev, hdev->vqs + i, hdev->vq_index + i);
         if (r < 0) {
@@ -1086,8 +1079,6 @@  int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
         }
     }
 
-    hdev->features = features;
-
     hdev->memory_listener = (MemoryListener) {
         .begin = vhost_begin,
         .commit = vhost_commit,