Re: [Qemu-block] [PATCH v9 4/6] block: convert ThrottleGroup to object with QOM

[Stefan Hajnoczi]

On Fri, Aug 25, 2017 at 04:20:26PM +0300, Manos Pitsidianakis wrote:
> ThrottleGroup is converted to an object. This will allow the future
> throttle block filter drive easy creation and configuration of throttle
> groups in QMP and cli.
> 
> A new QAPI struct, ThrottleLimits, is introduced to provide a shared
> struct for all throttle configuration needs in QMP.
> 
> ThrottleGroups can be created via CLI as
>     -object throttle-group,id=foo,x-iops-total=100,x-..
> where x-* are individual limit properties. Since we can't add non-scalar
> properties in -object this interface must be used instead. However,
> setting these properties must be disabled after initialization because
> certain combinations of limits are forbidden and thus configuration
> changes should be done in one transaction. The individual properties
> will go away when support for non-scalar values in CLI is implemented
> and thus are marked as experimental.
> 
> ThrottleGroup also has a `limits` property that uses the ThrottleLimits
> struct.  It can be used to create ThrottleGroups or set the
> configuration in existing groups as follows:
> 
> { "execute": "object-add",
>   "arguments": {
>     "qom-type": "throttle-group",
>     "id": "foo",
>     "props" : {
>       "limits": {
>           "iops-total": 100
>       }
>     }
>   }
> }
> { "execute" : "qom-set",
>     "arguments" : {
>         "path" : "foo",
>         "property" : "limits",
>         "value" : {
>             "iops-total" : 99
>         }
>     }
> }
> 
> This also means a group's configuration can be fetched with qom-get.
> 
> Signed-off-by: Manos Pitsidianakis <address@hidden>
> ---
>  qapi/block-core.json            |  48 +++++
>  include/block/throttle-groups.h |   3 +
>  include/qemu/throttle-options.h |  59 ++++--
>  include/qemu/throttle.h         |   3 +
>  block/throttle-groups.c         | 422 
> ++++++++++++++++++++++++++++++++++++----
>  tests/test-throttle.c           |   1 +
>  util/throttle.c                 | 151 ++++++++++++++
>  7 files changed, 627 insertions(+), 60 deletions(-)

Reviewed-by: Stefan Hajnoczi <address@hidden>