[PATCH v6 2/6] qmp: add QMP command x-debug-virtio-status

Jonah Palmer posted 6 patches 4 years, 5 months ago
Maintainers: "Michael S. Tsirkin" <mst@redhat.com>, Amit Shah <amit@kernel.org>, Michael Roth <michael.roth@amd.com>, "Marc-André Lureau" <marcandre.lureau@redhat.com>, Max Reitz <mreitz@redhat.com>, David Hildenbrand <david@redhat.com>, Markus Armbruster <armbru@redhat.com>, Stefan Hajnoczi <stefanha@redhat.com>, Eric Auger <eric.auger@redhat.com>, Gerd Hoffmann <kraxel@redhat.com>, "Dr. David Alan Gilbert" <dgilbert@redhat.com>, Jason Wang <jasowang@redhat.com>, Fam Zheng <fam@euphon.net>, Eric Blake <eblake@redhat.com>, Kevin Wolf <kwolf@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>, Laurent Vivier <lvivier@redhat.com>, Thomas Huth <thuth@redhat.com>
[PATCH v6 2/6] qmp: add QMP command x-debug-virtio-status
Posted by Jonah Palmer 4 years, 5 months ago
From: Laurent Vivier <lvivier@redhat.com>

This new command shows the status of a VirtIODevice
(features, endianness and number of virtqueues)

Next patch will improve output by decoding feature bits.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
---
 hw/virtio/virtio-stub.c |  5 ++++
 hw/virtio/virtio.c      | 50 ++++++++++++++++++++++++++++++++
 qapi/virtio.json        | 76 +++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 131 insertions(+)

diff --git a/hw/virtio/virtio-stub.c b/hw/virtio/virtio-stub.c
index d4a88f5..ddb592f 100644
--- a/hw/virtio/virtio-stub.c
+++ b/hw/virtio/virtio-stub.c
@@ -12,3 +12,8 @@ VirtioInfoList *qmp_x_debug_query_virtio(Error **errp)
 {
     return qmp_virtio_unsupported(errp);
 }
+
+VirtioStatus *qmp_x_debug_virtio_status(const char* path, Error **errp)
+{
+    return qmp_virtio_unsupported(errp);
+}
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index f3fc1bb..222330a 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -3896,6 +3896,56 @@ VirtioInfoList *qmp_x_debug_query_virtio(Error **errp)
     return list;
 }
 
+static VirtIODevice *virtio_device_find(const char *path)
+{
+    VirtIODevice *vdev;
+
+    QTAILQ_FOREACH(vdev, &virtio_list, next) {
+        DeviceState *dev = DEVICE(vdev);
+
+        if (strcmp(dev->canonical_path, path) != 0) {
+            continue;
+        }
+        return vdev;
+    }
+
+    return NULL;
+}
+
+VirtioStatus *qmp_x_debug_virtio_status(const char* path, Error **errp)
+{
+    VirtIODevice *vdev;
+    VirtioStatus *status;
+
+    vdev = virtio_device_find(path);
+    if (vdev == NULL) {
+        error_setg(errp, "Path %s is not a VirtIO device", path);
+        return NULL;
+    }
+
+    status = g_new0(VirtioStatus, 1);
+    status->guest_features = vdev->guest_features;
+    status->host_features = vdev->host_features;
+    status->backend_features = vdev->backend_features;
+    status->device_id = vdev->device_id;
+
+    switch (vdev->device_endian) {
+    case VIRTIO_DEVICE_ENDIAN_LITTLE:
+        status->device_endian = VIRTIO_STATUS_ENDIANNESS_LITTLE;
+        break;
+    case VIRTIO_DEVICE_ENDIAN_BIG:
+        status->device_endian = VIRTIO_STATUS_ENDIANNESS_BIG;
+        break;
+    default:
+        status->device_endian = VIRTIO_STATUS_ENDIANNESS_UNKNOWN;
+        break;
+    }
+
+    status->num_vqs = virtio_get_num_queues(vdev);
+
+    return status;
+}
+
 static const TypeInfo virtio_device_info = {
     .name = TYPE_VIRTIO_DEVICE,
     .parent = TYPE_DEVICE,
diff --git a/qapi/virtio.json b/qapi/virtio.json
index 804adbe..4bd09c9 100644
--- a/qapi/virtio.json
+++ b/qapi/virtio.json
@@ -70,3 +70,79 @@
 ##
 
 { 'command': 'x-debug-query-virtio', 'returns': ['VirtioInfo'] }
+
+##
+# @VirtioStatusEndianness:
+#
+# Enumeration of endianness for VirtioDevice
+#
+# Since: 6.1
+##
+{ 'enum': 'VirtioStatusEndianness',
+  'data': [ 'unknown', 'little', 'big' ]
+}
+
+##
+# @VirtioStatus:
+#
+# @device-id: VirtIODevice status
+#
+# @device-endian: VirtIODevice device_endian
+#
+# @guest-features: VirtIODevice guest_features
+#
+# @host-features: VirtIODevice host_features
+#
+# @backend-features: VirtIODevice backend_features
+#
+# @num-vqs: number of VirtIODevice queues
+#
+# Since: 6.1
+#
+##
+
+{ 'struct': 'VirtioStatus',
+  'data': {
+    'device-id': 'int',
+    'device-endian': 'VirtioStatusEndianness',
+    'guest-features': 'uint64',
+    'host-features': 'uint64',
+    'backend-features': 'uint64',
+    'num-vqs': 'uint16'
+  }
+}
+
+##
+# @x-debug-virtio-status:
+#
+# Return the status of virtio device
+#
+# @path: QOBject path of the VirtIODevice
+#
+# Returns: status of the VirtIODevice
+#
+# Since: 6.1
+#
+# Example:
+#
+# -> { "execute": "x-debug-virtio-status",
+#      "arguments": {
+#          "path": "/machine/peripheral-anon/device[3]/virtio-backend"
+#      }
+#   }
+# <- { "return": {
+#          "backend-features": 0,
+#          "guest-features": 5111807911,
+#          "num-vqs": 3,
+#          "host-features": 6337593319,
+#          "device-endian": "little",
+#          "device-id": 1
+#      }
+#    }
+#
+##
+
+{ 'command': 'x-debug-virtio-status',
+  'data': { 'path': 'str' },
+  'returns': 'VirtioStatus'
+}
-- 
1.8.3.1


Re: [PATCH v6 2/6] qmp: add QMP command x-debug-virtio-status
Posted by Markus Armbruster 4 years, 4 months ago
Jonah Palmer <jonah.palmer@oracle.com> writes:

> From: Laurent Vivier <lvivier@redhat.com>
>
> This new command shows the status of a VirtIODevice
> (features, endianness and number of virtqueues)
>
> Next patch will improve output by decoding feature bits.
>
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>

[...]

> diff --git a/qapi/virtio.json b/qapi/virtio.json
> index 804adbe..4bd09c9 100644
> --- a/qapi/virtio.json
> +++ b/qapi/virtio.json
> @@ -70,3 +70,79 @@
>  ##
>  
>  { 'command': 'x-debug-query-virtio', 'returns': ['VirtioInfo'] }
> +
> +##
> +# @VirtioStatusEndianness:
> +#
> +# Enumeration of endianness for VirtioDevice
> +#
> +# Since: 6.1

6.2 now, here, below, and in the remainder of this series.

> +##
> +{ 'enum': 'VirtioStatusEndianness',
> +  'data': [ 'unknown', 'little', 'big' ]
> +}
> +
> +##
> +# @VirtioStatus:
> +#
> +# @device-id: VirtIODevice status

"status"?  Really?

> +#
> +# @device-endian: VirtIODevice device_endian
> +#
> +# @guest-features: VirtIODevice guest_features
> +#
> +# @host-features: VirtIODevice host_features
> +#
> +# @backend-features: VirtIODevice backend_features
> +#
> +# @num-vqs: number of VirtIODevice queues
> +#
> +# Since: 6.1
> +#
> +##
> +
> +{ 'struct': 'VirtioStatus',
> +  'data': {
> +    'device-id': 'int',

VirtIODevice member @device_id is uint64_t.  Should this be 'uint16'?

> +    'device-endian': 'VirtioStatusEndianness',
> +    'guest-features': 'uint64',
> +    'host-features': 'uint64',
> +    'backend-features': 'uint64',
> +    'num-vqs': 'uint16'

virtio_get_num_queues() returns int.  Sure 'uint16' is the right type?

> +  }
> +}
> +
> +##
> +# @x-debug-virtio-status:
> +#
> +# Return the status of virtio device

"of a virtio device"

> +#
> +# @path: QOBject path of the VirtIODevice

"QOM path", please.

> +#
> +# Returns: status of the VirtIODevice
> +#
> +# Since: 6.1
> +#
> +# Example:
> +#
> +# -> { "execute": "x-debug-virtio-status",
> +#      "arguments": {
> +#          "path": "/machine/peripheral-anon/device[3]/virtio-backend"
> +#      }
> +#   }
> +# <- { "return": {
> +#          "backend-features": 0,
> +#          "guest-features": 5111807911,
> +#          "num-vqs": 3,
> +#          "host-features": 6337593319,
> +#          "device-endian": "little",
> +#          "device-id": 1
> +#      }
> +#    }
> +#
> +##
> +
> +{ 'command': 'x-debug-virtio-status',
> +  'data': { 'path': 'str' },
> +  'returns': 'VirtioStatus'
> +}


Re: [PATCH v6 2/6] qmp: add QMP command x-debug-virtio-status
Posted by Jonah Palmer 4 years, 4 months ago
On 8/7/21 8:42 AM, Markus Armbruster wrote:
> Jonah Palmer <jonah.palmer@oracle.com> writes:
>
>> From: Laurent Vivier <lvivier@redhat.com>
>>
>> This new command shows the status of a VirtIODevice
>> (features, endianness and number of virtqueues)
>>
>> Next patch will improve output by decoding feature bits.
>>
>> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
>> Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
> [...]
>
>> diff --git a/qapi/virtio.json b/qapi/virtio.json
>> index 804adbe..4bd09c9 100644
>> --- a/qapi/virtio.json
>> +++ b/qapi/virtio.json
>> @@ -70,3 +70,79 @@
>>   ##
>>   
>>   { 'command': 'x-debug-query-virtio', 'returns': ['VirtioInfo'] }
>> +
>> +##
>> +# @VirtioStatusEndianness:
>> +#
>> +# Enumeration of endianness for VirtioDevice
>> +#
>> +# Since: 6.1
> 6.2 now, here, below, and in the remainder of this series.
>
>> +##
>> +{ 'enum': 'VirtioStatusEndianness',
>> +  'data': [ 'unknown', 'little', 'big' ]
>> +}
>> +
>> +##
>> +# @VirtioStatus:
>> +#
>> +# @device-id: VirtIODevice status
> "status"?  Really?

I'll change it to 'VirtIODevice ID' instead

>
>> +#
>> +# @device-endian: VirtIODevice device_endian
>> +#
>> +# @guest-features: VirtIODevice guest_features
>> +#
>> +# @host-features: VirtIODevice host_features
>> +#
>> +# @backend-features: VirtIODevice backend_features
>> +#
>> +# @num-vqs: number of VirtIODevice queues
>> +#
>> +# Since: 6.1
>> +#
>> +##
>> +
>> +{ 'struct': 'VirtioStatus',
>> +  'data': {
>> +    'device-id': 'int',
> VirtIODevice member @device_id is uint64_t.  Should this be 'uint16'?

Ah, yes this should be uint16. I'll update this.

>
>> +    'device-endian': 'VirtioStatusEndianness',
>> +    'guest-features': 'uint64',
>> +    'host-features': 'uint64',
>> +    'backend-features': 'uint64',
>> +    'num-vqs': 'uint16'
> virtio_get_num_queues() returns int.  Sure 'uint16' is the right type?

Yes, you're right, it should be an 'int' instead. I'll also update this.

>
>> +  }
>> +}
>> +
>> +##
>> +# @x-debug-virtio-status:
>> +#
>> +# Return the status of virtio device
> "of a virtio device"

Oops! Forgot the article, thank you.

>
>> +#
>> +# @path: QOBject path of the VirtIODevice
> "QOM path", please.
>
>> +#
>> +# Returns: status of the VirtIODevice
>> +#
>> +# Since: 6.1
>> +#
>> +# Example:
>> +#
>> +# -> { "execute": "x-debug-virtio-status",
>> +#      "arguments": {
>> +#          "path": "/machine/peripheral-anon/device[3]/virtio-backend"
>> +#      }
>> +#   }
>> +# <- { "return": {
>> +#          "backend-features": 0,
>> +#          "guest-features": 5111807911,
>> +#          "num-vqs": 3,
>> +#          "host-features": 6337593319,
>> +#          "device-endian": "little",
>> +#          "device-id": 1
>> +#      }
>> +#    }
>> +#
>> +##
>> +
>> +{ 'command': 'x-debug-virtio-status',
>> +  'data': { 'path': 'str' },
>> +  'returns': 'VirtioStatus'
>> +}
Re: [PATCH v6 2/6] qmp: add QMP command x-debug-virtio-status
Posted by Michael S. Tsirkin 4 years, 3 months ago
On Mon, Jul 12, 2021 at 06:35:33AM -0400, Jonah Palmer wrote:
> From: Laurent Vivier <lvivier@redhat.com>
> 
> This new command shows the status of a VirtIODevice
> (features, endianness and number of virtqueues)
> 
> Next patch will improve output by decoding feature bits.
> 
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>

Do we want to also decode the device status?
E.g. does it have driver, need reset, etc etc?

Also, the internal broken flag?


> ---
>  hw/virtio/virtio-stub.c |  5 ++++
>  hw/virtio/virtio.c      | 50 ++++++++++++++++++++++++++++++++
>  qapi/virtio.json        | 76 +++++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 131 insertions(+)
> 
> diff --git a/hw/virtio/virtio-stub.c b/hw/virtio/virtio-stub.c
> index d4a88f5..ddb592f 100644
> --- a/hw/virtio/virtio-stub.c
> +++ b/hw/virtio/virtio-stub.c
> @@ -12,3 +12,8 @@ VirtioInfoList *qmp_x_debug_query_virtio(Error **errp)
>  {
>      return qmp_virtio_unsupported(errp);
>  }
> +
> +VirtioStatus *qmp_x_debug_virtio_status(const char* path, Error **errp)
> +{
> +    return qmp_virtio_unsupported(errp);
> +}
> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
> index f3fc1bb..222330a 100644
> --- a/hw/virtio/virtio.c
> +++ b/hw/virtio/virtio.c
> @@ -3896,6 +3896,56 @@ VirtioInfoList *qmp_x_debug_query_virtio(Error **errp)
>      return list;
>  }
>  
> +static VirtIODevice *virtio_device_find(const char *path)
> +{
> +    VirtIODevice *vdev;
> +
> +    QTAILQ_FOREACH(vdev, &virtio_list, next) {
> +        DeviceState *dev = DEVICE(vdev);
> +
> +        if (strcmp(dev->canonical_path, path) != 0) {
> +            continue;
> +        }
> +        return vdev;
> +    }
> +
> +    return NULL;
> +}
> +
> +VirtioStatus *qmp_x_debug_virtio_status(const char* path, Error **errp)
> +{
> +    VirtIODevice *vdev;
> +    VirtioStatus *status;
> +
> +    vdev = virtio_device_find(path);
> +    if (vdev == NULL) {
> +        error_setg(errp, "Path %s is not a VirtIO device", path);
> +        return NULL;
> +    }
> +
> +    status = g_new0(VirtioStatus, 1);
> +    status->guest_features = vdev->guest_features;
> +    status->host_features = vdev->host_features;
> +    status->backend_features = vdev->backend_features;
> +    status->device_id = vdev->device_id;
> +
> +    switch (vdev->device_endian) {
> +    case VIRTIO_DEVICE_ENDIAN_LITTLE:
> +        status->device_endian = VIRTIO_STATUS_ENDIANNESS_LITTLE;
> +        break;
> +    case VIRTIO_DEVICE_ENDIAN_BIG:
> +        status->device_endian = VIRTIO_STATUS_ENDIANNESS_BIG;
> +        break;
> +    default:
> +        status->device_endian = VIRTIO_STATUS_ENDIANNESS_UNKNOWN;
> +        break;
> +    }
> +
> +    status->num_vqs = virtio_get_num_queues(vdev);
> +
> +    return status;
> +}
> +
>  static const TypeInfo virtio_device_info = {
>      .name = TYPE_VIRTIO_DEVICE,
>      .parent = TYPE_DEVICE,
> diff --git a/qapi/virtio.json b/qapi/virtio.json
> index 804adbe..4bd09c9 100644
> --- a/qapi/virtio.json
> +++ b/qapi/virtio.json
> @@ -70,3 +70,79 @@
>  ##
>  
>  { 'command': 'x-debug-query-virtio', 'returns': ['VirtioInfo'] }
> +
> +##
> +# @VirtioStatusEndianness:
> +#
> +# Enumeration of endianness for VirtioDevice
> +#
> +# Since: 6.1
> +##
> +{ 'enum': 'VirtioStatusEndianness',
> +  'data': [ 'unknown', 'little', 'big' ]
> +}
> +
> +##
> +# @VirtioStatus:
> +#
> +# @device-id: VirtIODevice status
> +#
> +# @device-endian: VirtIODevice device_endian
> +#
> +# @guest-features: VirtIODevice guest_features
> +#
> +# @host-features: VirtIODevice host_features
> +#
> +# @backend-features: VirtIODevice backend_features
> +#
> +# @num-vqs: number of VirtIODevice queues
> +#
> +# Since: 6.1
> +#
> +##
> +
> +{ 'struct': 'VirtioStatus',
> +  'data': {
> +    'device-id': 'int',
> +    'device-endian': 'VirtioStatusEndianness',
> +    'guest-features': 'uint64',
> +    'host-features': 'uint64',
> +    'backend-features': 'uint64',
> +    'num-vqs': 'uint16'
> +  }
> +}
> +
> +##
> +# @x-debug-virtio-status:
> +#
> +# Return the status of virtio device
> +#
> +# @path: QOBject path of the VirtIODevice
> +#
> +# Returns: status of the VirtIODevice
> +#
> +# Since: 6.1
> +#
> +# Example:
> +#
> +# -> { "execute": "x-debug-virtio-status",
> +#      "arguments": {
> +#          "path": "/machine/peripheral-anon/device[3]/virtio-backend"
> +#      }
> +#   }
> +# <- { "return": {
> +#          "backend-features": 0,
> +#          "guest-features": 5111807911,
> +#          "num-vqs": 3,
> +#          "host-features": 6337593319,
> +#          "device-endian": "little",
> +#          "device-id": 1
> +#      }
> +#    }
> +#
> +##
> +
> +{ 'command': 'x-debug-virtio-status',
> +  'data': { 'path': 'str' },
> +  'returns': 'VirtioStatus'
> +}
> -- 
> 1.8.3.1