Re: [Qemu-devel] [PATCH 14/17] add new RanState RAN_STATE_FLIPPING_MIGRATE

[Lei Li <lilei@linux.vnet.ibm.com>]

On 10/22/2013 11:51 AM, Eric Blake wrote:
> On 10/22/2013 04:25 AM, Lei Li wrote:
>> Introduce new RanState RAN_STATE_FLIPPING_MIGRATE and
>> add it to runstate_needs_reset().
>>
>> Signed-off-by: Lei Li <lilei@linux.vnet.ibm.com>
>> ---
>>   qapi-schema.json |   11 +++++++----
>>   vl.c             |   12 +++++++++++-
>>   2 files changed, 18 insertions(+), 5 deletions(-)
>>
>> diff --git a/qapi-schema.json b/qapi-schema.json
>> index 523a5b2..8178d0c 100644
>> --- a/qapi-schema.json
>> +++ b/qapi-schema.json
>> @@ -176,12 +176,15 @@
>>   # @watchdog: the watchdog action is configured to pause and has been triggered
>>   #
>>   # @guest-panicked: guest has been panicked as a result of guest OS panic
>> +#
>> +# @flipping-migrate: guest is paused to start unix_page_flipping migration
>> +# process
> We probably ought to enhance the docs to mention '(since 1.8)' for this
> field (and likewise for other enum values added after the original
> introduction of the enum).

Hi Eric,

Sure, will do.

BTW, I was hoping this feature could be accepted and merged to QEMU 1.7
release.

>
> Last time we added a new user-visible runstate, it broke migration with
> older libvirt versions that weren't prepared to see the new state (hmm,
> I need to check if libvirt has fixed that in the meantime; adding a
> cc...).  Paolo's advice at the time was that it is okay to require a new
> libvirt when using a new qemu, and that libvirt should be taught to
> treat all unknown RunState as if they were 'running'; although for this
> particular addition it might be nicer to have libvirt lump 'inmigrate'
> and 'flipping-migrate' to the same usage.

I am not sure whether these two runstate could be lumped with same usage
in libvirt. Whatever, looks like 'inmigrate' has a transition from 'prelaunch'
to it in QEMU, which reminds me that it may need to add another transition
from 'prelaunch' to 'flipping-migrate' too.

>
>>   ##
>>   { 'enum': 'RunState',
>> -  'data': [ 'debug', 'inmigrate', 'internal-error', 'io-error', 'paused',
>> -            'postmigrate', 'prelaunch', 'finish-migrate', 'restore-vm',
>> -            'running', 'save-vm', 'shutdown', 'suspended', 'watchdog',
>> -            'guest-panicked' ] }
>> +  'data': [ 'debug', 'flipping-migrate', 'inmigrate', 'internal-error',
>> +            'io-error', 'paused', 'postmigrate', 'prelaunch', 'finish-migrate',
>> +            'restore-vm', 'running', 'save-vm', 'shutdown', 'suspended',
>> +            'watchdog', 'guest-panicked' ] }
>>   
>


-- 
Lei