Re: Question about nohz and sysidle

[Yu Liao]

Sorry, I sent to the old email address.

On 2022/2/14 16:28, Yu Liao wrote:
> Hi Frederic,
>
> I'm working on an issue about nohz. When NO_HZ_FULL is enabled, CPU 0 
> handles the timekeeping duty on behalf of all other CPUs, which means 
> CPU 0 never stop tick even in sysidle state. This is a powersaving issue.
>
> I found your patchset (nohz: Support sysidle) in the below link.
> https://lore.kernel.org/all/1406569056-30217-1-git-send-email-fweisbec@xxxxxxxxx/ 
>
> But these patches haven't been merged into mainline yet and sysidle 
> state detection has been removed by commit fe5ac724d81a (rcu: Remove 
> nohz_full full-system-idle state machine) as well.
>
> I tried your patches and it does work, why are we no longer 
> working on stopping timekeeping duty when all full dynticks CPUs are idle?
>
> Thanks,
> Yu