Re: [PATCH v5 3/3] sched/cputime: Add steal time support to full dynticks CPU time accounting

[Wanpeng Li]

2016-06-08 15:22 GMT+08:00 Ingo Molnar <mingo@xxxxxxxxxx>:
>
> * Wanpeng Li <kernellwp@xxxxxxxxx> wrote:
>
>> From: Wanpeng Li <wanpeng.li@xxxxxxxxxxx>
>>
>> This patch adds guest steal-time support to full dynticks CPU
>> time accounting. After the following commit:
>>
>> ff9a9b4c4334 ("sched, time: Switch VIRT_CPU_ACCOUNTING_GEN to jiffy granularity")
>>
>> ... time sampling became jiffy based, even if it's still listened
>> to ring boundaries, so steal_account_process_tick() is reused
>> to account how many 'ticks' are stolen-time, after the last accumulation.
>
> So the 'ring boundary' part still doesn't parse (neither grammatically nor
> logically) - please rephrase it because I have no idea what you want to say here.

It is original from this slides.
http://ertl.jp/~shinpei/conf/ospert13/slides/FredericWeisbecker.pdf,
slide 28.

>
> Did you want to say:
>
>> ... time sampling became jiffy based, even if it's still being context tracked,
>> so steal_account_process_tick() is reused to account how many 'ticks' are
>> stolen-time, after the last accumulation.
>
> ... which makes sense grammatically but does not make sense to me logically. :-/
>
> Rik, Frederic, could you please help out?
>
> Thanks,
>
>         Ingo