block: add block_set_io_throttle virtio-blk-pci QMP example

The block_set_io_throttle command can look up BlockBackends by the
attached qdev device ID.  virtio-blk-pci is a special case because the
actual VirtIOBlock device is the "/virtio-backend" child of the PCI
adapter device.

Add a QMP schema example so clients will know how to use
block_set_io_throttle on the virtio-blk-pci device.

The alternative is to implement some sort of aliasing for qmp_get_blk()
but that is likely to cause confusion and could break future use cases.
Let's not go there.

Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 20180117090700.25811-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Stefan Hajnoczi 2018-01-17 09:07:00 +00:00
parent b384cd95eb
commit dc15541d59

View File

@ -1799,6 +1799,24 @@
# Example:
#
# -> { "execute": "block_set_io_throttle",
# "arguments": { "id": "virtio-blk-pci0/virtio-backend",
# "bps": 0,
# "bps_rd": 0,
# "bps_wr": 0,
# "iops": 512,
# "iops_rd": 0,
# "iops_wr": 0,
# "bps_max": 0,
# "bps_rd_max": 0,
# "bps_wr_max": 0,
# "iops_max": 0,
# "iops_rd_max": 0,
# "iops_wr_max": 0,
# "bps_max_length": 0,
# "iops_size": 0 } }
# <- { "return": {} }
#
# -> { "execute": "block_set_io_throttle",
# "arguments": { "id": "ide0-1-0",
# "bps": 1000000,
# "bps_rd": 0,