Re: [PATCH v3 10/10] migration/dirtyrate: Implement qmp_cal_dirty_rate()/qmp_get_dirty_rate() function

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Eric Blake (eblake@redhat.com) wrote:
> On 8/16/20 10:20 PM, Chuan Zheng wrote:
> > Implement qmp_cal_dirty_rate()/qmp_get_dirty_rate() function which could be called
> > 
> > Signed-off-by: Chuan Zheng <zhengchuan@huawei.com>
> > ---
> 
> > +++ b/qapi/migration.json
> > @@ -1621,3 +1621,45 @@
> >   ##
> >   { 'event': 'UNPLUG_PRIMARY',
> >     'data': { 'device-id': 'str' } }
> > +
> > +##
> > +# @DirtyRateInfo:
> > +#
> > +# Information about current dirty page rate of vm.
> > +#
> > +# @dirty-rate: @dirtyrate describing the dirty page rate of vm
> > +#          in units of MB/s.
> > +#          If this field return '-1', it means querying is not
> > +#          start or not complete.
> > +#
> > +# @status: @status containing dirtyrate query status includes
> > +#       status with 'not start measuring' or
> > +#       'Still measuring' or 'measured'(since 5.2)
> 
> Missing space before (
> 
> > +##
> > +{ 'struct': 'DirtyRateInfo',
> > +  'data': {'dirty-rate': 'int64',
> > +           'status': 'str'} }
> 
> Based on your description, this should be an enum type rather than an
> open-coded string.  Something like:
> 
> { 'enum': 'DirtyRateStatus', 'data': [ 'unstarted', 'measuring', 'measured'
> ] }
> { 'struct': 'DirtyRateInfo', 'data': { 'dirty-rate': 'int64', 'status':
> 'DirtyRateStatus' } }

Yes, and if you do that I think you'll find qmp would automatically
define a C enum type for you, so you don't need to define the
CalculatingDirtyRateStage yourself;   see how MigrationStatus works.

Dave


> 
> > +
> > +##
> > +# @calc-dirty-rate:
> > +#
> > +# start calculating dirty page rate for vm
> > +#
> > +# @calc-time: time in units of second for sample dirty pages
> > +#
> > +# Since: 5.2
> > +#
> > +# Example:
> > +#   {"command": "cal-dirty-rate", "data": {"calc-time": 1} }
> > +#
> > +##
> > +{ 'command': 'calc-dirty-rate', 'data': {'calc-time': 'int64'} }
> > +
> > +##
> > +# @query-dirty-rate:
> > +#
> > +# query dirty page rate in units of MB/s for vm
> > +#
> > +# Since: 5.2
> > +##
> > +{ 'command': 'query-dirty-rate', 'returns': 'DirtyRateInfo' }
> > 
> 
> -- 
> Eric Blake, Principal Software Engineer
> Red Hat, Inc.           +1-919-301-3226
> Virtualization:  qemu.org | libvirt.org
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK