Re: [External] Re: [PATCH v3 1/7] migration/multifd: Add new migration option zero-page-detection.

[Markus Armbruster <armbru@redhat.com>]

Hao Xiang <hao.xiang@bytedance.com> writes:

> On Wed, Feb 28, 2024 at 1:43 AM Markus Armbruster <armbru@redhat.com> wrote:
>>
>> Hao Xiang <hao.xiang@bytedance.com> writes:
>>
>> > This new parameter controls where the zero page checking is running.
>> > 1. If this parameter is set to 'legacy', zero page checking is
>> > done in the migration main thread.
>> > 2. If this parameter is set to 'none', zero page checking is disabled.
>> >
>> > Signed-off-by: Hao Xiang <hao.xiang@bytedance.com>
>>
>> [...]
>>
>> > diff --git a/qapi/migration.json b/qapi/migration.json
>> > index 5a565d9b8d..1e66272f8f 100644
>> > --- a/qapi/migration.json
>> > +++ b/qapi/migration.json
>> > @@ -653,6 +653,18 @@
>> >  { 'enum': 'MigMode',
>> >    'data': [ 'normal', 'cpr-reboot' ] }
>> >
>> > +##
>> > +# @ZeroPageDetection:
>> > +#
>> > +# @none: Do not perform zero page checking.
>> > +#
>> > +# @legacy: Perform zero page checking from main migration thread.
>> > +#
>> > +# Since: 9.0
>> > +##
>> > +{ 'enum': 'ZeroPageDetection',
>> > +  'data': [ 'none', 'legacy' ] }
>> > +
>> >  ##
>> >  # @BitmapMigrationBitmapAliasTransform:
>> >  #
>> > @@ -874,6 +886,9 @@
>> >  # @mode: Migration mode. See description in @MigMode. Default is 'normal'.
>> >  #        (Since 8.2)
>> >  #
>> > +# @zero-page-detection: Whether and how to detect zero pages. More details
>> > +#     see description in @ZeroPageDetection. Default is 'legacy'.  (since 9.0)
>> > +#
>>
>> I'm not sure we need to point to the member's type.  If we want to, we
>> better fix the prose: "For additional information, see
>> @ZeroPageDetection" or similar.
>
> This is mimicking what was done for the "mode" migration option. There
> aren't many enumeration types on the interface I can learn from.
>
> Existing code
>
> #
> # @mode: Migration mode. See description in @MigMode. Default is 'normal'.
> # (Since 8.2)

"More details see description in @TYPE" feels off, "See description in
@TYPE" is better.  Feel free to use it instead of my suggested phrasing.

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