Re: AMD Pstate

On Tue, 23 Nov 2021 at 11:18, Huang Rui [off-list ref] wrote:

On Tue, Nov 23, 2021 at 06:47:34PM +0800, Mike Lothian wrote:

quoted

Hi again

Do I need to enable something else for shedutil to work, I've tried
with and without shared_mem? Compiling a kernel with -j16 has the freq
stuck at 1GHz on all cores - ondemand works fine

If you set the CONFIG_CPU_FREQ_GOV_SCHEDUTIL, then no more configurations.

Did you use the V4 version?

https://git.kernel.org/pub/scm/linux/kernel/git/rui/linux.git/log/?h=amd-pstate-dev-v4

quoted

That's on a AMD Ryzen 9 5900HX

Also compiling with Clang-13 gives the following warnings:

drivers/cpufreq/amd-pstate.c:257:6: warning: variable 'amd_des_perf'
is used uninitialized whenever 'if' condition is false
[-Wsometimes-uninitialized]

        if (target_perf < capacity)

            ^~~~~~~~~~~~~~~~~~~~~~

drivers/cpufreq/amd-pstate.c:272:40: note: uninitialized use occurs here

        amd_des_perf = clamp_t(unsigned long, amd_des_perf,

                                              ^~~~~~~~~~~~

Ah, miss one line. Thanks for the info. I will correct it.

Thanks,
Ray

Hi

Yes I used v4 and CONFIG_CPU_FREQ_GOV_SCHEDUTIL was set as the
default, is there any other info that would be useful, I can switch
back to schedutil from ondemand and collect for you

Cheers

Mike