Re: [PATCH v14 04/17] Introduce pv guest type and has_hvm_container macros

[George Dunlap <george.dunlap@eu.citrix.com>]

On 04/11/13 16:20, Jan Beulich wrote:
>>>> On 04.11.13 at 13:14, George Dunlap <george.dunlap@eu.citrix.com> wrote:
>> The goal of this patch is to classify conditionals more clearly, as to
>> whether they relate to pv guests, hvm-only guests, or guests with an
>> "hvm container" (which will eventually include PVH).
>>
>> This patch introduces an enum for guest type, as well as two new macros
>> for switching behavior on and off: is_pv_* and has_hvm_container_*.  At the
>> moment is_pv_* <=> !has_hvm_container_*.  The purpose of having two is that
>> it seems to me different to take a path because something does *not* have PV
>> structures as to take a path because it *does* have HVM structures, even if
>> the
>> two happen to coincide 100% at the moment.  The exact usage is occasionally
>> a bit
>> fuzzy though, and a judgement call just needs to be made on which is
>> clearer.
>>
>> In general, a switch should use is_pv_* (or !is_pv_*) if the code in
>> question
>> relates directly to a PV guest.  Examples include use of pv_vcpu structs or
>> other behavior directly related to PV domains.
>>
>> hvm_container is more of a fuzzy concept, but in general:
> So sadly this is still being retained, despite its redundancy.

Jan,

Given that the long-term plan is to get rid of the extra mode entirely 
(at which point has_hvm_container will also go away), are you OK with 
this patchset going in as it is?

There are a lot of individual places to change, and I'm a bit afraid 
that a large change like that will introduce some bugs I'll have to 
spend more time tracking down... I'd rather just do all the changes when 
we get rid of the extra mode, if possible.

  -George