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Re: Which should kcpuset use cpuid or cpu index?



On Sep 7, 2014, at 8:51 PM, Kengo NAKAHARA <k-nakahara%iij.ad.jp@localhost> 
wrote:

> Hi,
> 
> Thank you for answer.
> 
> (2014/09/08 12:34), Matt Thomas wrote:
>> 
>> On Sep 7, 2014, at 7:28 PM, Kengo NAKAHARA <k-nakahara%iij.ad.jp@localhost> 
>> wrote:
>> 
>>> I have a question about kcpuset. Referring "man 9 kcpuset", the APIs
>>> need cpuid (the type is cpuid_t) to identify CPU. However, the callers
>>> such as idle_loop() sys/kern/kern_idle.c use cpu index (the type is u_int).
>>> 
>>> cpu index means return value of cpu_index(), and cpu index is sequential
>>> number. On the other hand, cpuid means struct cpu_info.ci_cpuid and cpuid
>>> is non-sequential number at least x86 and sparc architectures. So, cpu index
>>> is different from cpuid. Which should kcpuset use cpuid or cpu index?
>> 
>> ci_cpuid is MD and has no standard semantics.
>> 
>> Use cpu_index(ci) (curcpu()->ci_index)
> 
> I see. So, should kcpuset APIs use u_int (not cpuid_t)? As cpu_index()
> which is MI function in sys/sys/cpu.h returns u_int type.

I don't think it matters since it's a u_long.


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