Re: [PATCH] arm64: defconfig: Select schedutil as default cpufreq governor
From: Arnd Bergmann
Date: Thu Dec 21 2017 - 10:32:39 EST
On Mon, Dec 18, 2017 at 5:29 AM, Viresh Kumar <viresh.kumar@xxxxxxxxxx> wrote:
> On 15-12-17, 15:50, Catalin Marinas wrote:
>> On Thu, Nov 16, 2017 at 11:51:36AM +0530, Viresh Kumar wrote:
>> > Currently performance governor is getting selected by default, which is
>> > surely not a very good choice as its pretty much power hungry.
>> > Select schedutil instead.
>> And why do we care about this in defconfig? People deploying their own
>> kernels in mobile may opt for this config, others may prefer the default
>> Also it seems it would be the only architecture make this governor the
>> default, so NAK.
> This is a bit dangerous configuration IMHO.
> Other architectures have some *real* governor selected by default, like Ondemand
> or Conservative. Running your CPUs at max (because of the default performance
> governor in arm64 config) may end up burning some SoCs accidentally just because
> their thermal stuff doesn't kick in to cool SoC down properly.
> So, we should have one of ondemand, conservative and schedutil selected by
> default for arm64 as well IMO and schedutil is the one which every one is
> falling back to now a days, even android.
Maybe it's time to change the global 'default
CPU_FREQ_DEFAULT_GOV_PERFORMANCE' instead to avoid having to
do this for each architecture separately?
I think the general idea of using schedutil or ondemand instead of performance
makes sense, but it doesn't feel right to have to do this for every
that doesn't select a default.