Re: [PATCH V3 0/4] cpufreq: cppc: Add support for frequency invariance

On 25-06-21, 22:29, Qian Cai wrote:

Ionela, I found that set ACPI_PROCESSOR=y instead of
ACPI_PROCESSOR=m will fix the previous mentioned issues here (any
explanations of that?) even though the scaling down is not perfect.

Not sure how this affects it.

Now, we have the following on this idle system:

# cat /sys/devices/system/cpu/*/cpufreq/cpuinfo_cur_freq | sort | uniq  -c
 	79 1000000
  	1 1160000
 	73 1400000
  	1 2000000
  	4 2010000
  	1 2800000
  	1 860000

Even if I rerun a few times, there could still have a few CPUs
running lower than lowest_perf (1GHz).

(Please wrap your lines at 80 columns, it makes it harder to read
otherwise).

I think only the counters stopping on idle can get us that.

Also, even though I set all CPUs to use "userspace" governor and set
freq to the lowest. A few CPUs keep changing at will.

# cat /sys/devices/system/cpu/*/cpufreq/cpuinfo_cur_freq | sort | uniq  -c
	156 1000000
  	3 2000000
  	1 760000

I think this is expected since the hardware is in control of frequency
here. The software can only request it to run at X frequency, the
hardware may choose to do something else nevertheless.

-- 
viresh