[libvirt] [RFC] New API to retrieve node CPU map

[Viktor Mihajlovski]

On 10/11/2012 06:06 AM, Eric Blake wrote:
> On 10/10/2012 10:02 PM, Osier Yang wrote:
>>> Are you interested in writing patches to implement this new API, if
>>> others agree with my alternate single-API signature?
>>
>> Agreed. A single-API and allocating the cpumap inside libvirt without
>> the need to known the maplen avoids the race.
>>
>> But a flags support won't bite us, assuming someone just want to get
>> the cpumap of the onlined CPUs, or offlined CPUs.
>
> Indeed, shame on me for not remember a flags argument for any possible
> future extensions.
>
>>
>> So how about:
>>
>> int
>> virNodeGetCpuMap(virConnectPtr conn,
>>                   unsigned char **cpumap,
>>                   unsigned int flags);
>
> Yes, that's better, even if flags must always be 0 for now.
>

No problem to include flags for future extensions to be on the safe 
side. However, the map will contain all CPUs with the bits representing 
the online/offline state. If the intention is to quickly get the number 
of offline/online CPUS the following signature would be better IMO

int
virNodeGetCpuMap(virConnectPtr conn,
                  unsigned char **cpumap,
		 unsigned int *online,
		 unsigned int *offline,
                  unsigned int flags);



-- 

Mit freundlichen Grüßen/Kind Regards
    Viktor Mihajlovski

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