Re: [PATCH 03/10] viridian: introduce a per-cpu hypercall_vpmask and accessor functions...

[Jan Beulich <jbeulich@xxxxxxxx>]

On 19.11.2020 17:44, Durrant, Paul wrote:
>> -----Original Message-----
>> From: Jan Beulich <jbeulich@xxxxxxxx>
>> Sent: 19 November 2020 16:41
>> To: paul@xxxxxxx
>> Cc: Durrant, Paul <pdurrant@xxxxxxxxxxxx>; 'Wei Liu' <wl@xxxxxxx>; 'Andrew 
>> Cooper'
>> <andrew.cooper3@xxxxxxxxxx>; 'Roger Pau Monné' <roger.pau@xxxxxxxxxx>; 
>> xen-devel@xxxxxxxxxxxxxxxxxxxx
>> Subject: RE: [EXTERNAL] [PATCH 03/10] viridian: introduce a per-cpu 
>> hypercall_vpmask and accessor
>> functions...
>>
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>>
>> On 19.11.2020 17:02, Paul Durrant wrote:
>>>> From: Jan Beulich <jbeulich@xxxxxxxx
>>>> Sent: 12 November 2020 08:46
>>>>
>>>> On 11.11.2020 21:07, Paul Durrant wrote:
>>>>> --- a/xen/arch/x86/hvm/viridian/viridian.c
>>>>> +++ b/xen/arch/x86/hvm/viridian/viridian.c
>>>>> @@ -507,15 +507,41 @@ void viridian_domain_deinit(struct domain *d)
>>>>>      XFREE(d->arch.hvm.viridian);
>>>>>  }
>>>>>
>>>>> +struct hypercall_vpmask {
>>>>> +    DECLARE_BITMAP(mask, HVM_MAX_VCPUS);
>>>>> +};
>>>>> +
>>>>> +static DEFINE_PER_CPU(struct hypercall_vpmask, hypercall_vpmask);
>>>>> +
>>>>> +static void vpmask_empty(struct hypercall_vpmask *vpmask)
>>>>
>>>> const?
>>>
>>> Yes, I suppose that's ook for all these since the outer struct is
>>> not changing... It's a bit misleading though.
>>
>> I'd be curious to learn about that "misleading" aspect.
>>
> 
> Because the function is modifying (zero-ing) the bitmap... so implying
> the mask is const is measleading.

Oh, I was mislead by the name then; should have looked at the return
type (which I was implying to be bool, when it's void). Please
disregard my request(s) in such case(s).

Jan