On 8/7/21 8:45 AM, Markus Armbruster wrote:
Jonah Palmer <jonah.palmer@oracle.com> writes:

From: Laurent Vivier <lvivier@redhat.com>

This new command shows internal status of a VirtQueue.
(vrings and indexes).

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 78873cd..7007e0c 100644
--- a/qapi/virtio.json
+++ b/qapi/virtio.json
@@ -406,3 +406,105 @@
   'data': { 'path': 'str' },
   'returns': 'VirtioStatus'
 }
+
+##
+# @VirtQueueStatus:
+#
+# Status of a VirtQueue
+#
+# @device-type: VirtIO device type
+#
+# @queue-index: VirtQueue queue_index
+#
+# @inuse: VirtQueue inuse
+#
+# @vring-num: VirtQueue vring.num
+#
+# @vring-num-default: VirtQueue vring.num_default
+#
+# @vring-align: VirtQueue vring.align
+#
+# @vring-desc: VirtQueue vring.desc
+#
+# @vring-avail: VirtQueue vring.avail
+#
+# @vring-used: VirtQueue vring.used
+#
+# @last-avail-idx: VirtQueue last_avail_idx
+#
+# @shadow-avail-idx: VirtQueue shadow_avail_idx
+#
+# @used-idx: VirtQueue used_idx
+#
+# @signalled-used: VirtQueue signalled_used
+#
+# @signalled-used-valid: VirtQueue signalled_used_valid
+#
+# Since: 6.1
+#
+##
+
+{ 'struct': 'VirtQueueStatus',
+  'data': {
+    'device-type': 'VirtioType',
+    'queue-index': 'uint16',
+    'inuse': 'uint32',
+    'vring-num': 'int',
+    'vring-num-default': 'int',
+    'vring-align': 'int',
+    'vring-desc': 'uint64',
+    'vring-avail': 'uint64',
+    'vring-used': 'uint64',
+    'last-avail-idx': 'uint16',
+    'shadow-avail-idx': 'uint16',
+    'used-idx': 'uint16',
+    'signalled-used': 'uint16',
+    'signalled-used-valid': 'uint16'
+  }
+}
I can't check the member types like I did for VirtioStatus in PATCH 2
right now.  Please double-check them.
Double-checked these; 'vring.num', 'vring.num_default', and 'vring.align'
are all of type 'unsigned int'. I think these should be of type 'uint32' here.

Also, 'signalled_used_valid' is of type bool, so I'll change it to 'bool'
here as well. 

+
+##
+# @x-debug-virtio-queue-status:
+#
+# Return the status of a given VirtQueue
+#
+# @path: QOBject path of the VirtIODevice
+#
+# @queue: queue number to examine
+#
+# Returns: Status of the VirtQueue
+#
+# Since: 6.1
+#
+# Example:
+#
+# -> { "execute": "x-debug-virtio-queue-status",
+#      "arguments": {
+#          "path": "/machine/peripheral-anon/device[3]/virtio-backend",
+#          "queue": 0
+#      }
+#   }
+# <- { "return": {
+#      "signalled-used": 373,
+#      "inuse": 0,
+#      "vring-align": 4096,
+#      "vring-desc": 864411648,
+#      "signalled-used-valid": 0,
+#      "vring-num-default": 256,
+#      "vring-avail": 864415744,
+#      "queue-index": 0,
+#      "last-avail-idx": 373,
+#      "vring-used": 864416320,
+#      "used-idx": 373,
+#      "device-type": "virtio-net",
+#      "shadow-avail-idx": 619,
+#      "vring-num": 256
+#      }
+#    }
+#
+##
+
+{ 'command': 'x-debug-virtio-queue-status',
+  'data': { 'path': 'str', 'queue': 'uint16' },
+  'returns': 'VirtQueueStatus'
+}