AMD P-State EPP Patches Spun An 8th Time For Helping Out Linux Performance & Efficiency

[ptr1337]

Yes, it's the default option. Should i disable it?

Yes, you can. It wont harm your kernel. WERROR just means that a warning triggers a failure in the compilation. Has been some time introduced as default enabled. But if you want to test patches from lkml better keep it disabled

[HD7950]

Yes, you can. It wont harm your kernel. WERROR just means that a warning triggers a failure in the compilation. Has been some time introduced as default enabled. But if you want to test patches from lkml better keep it disabled

Still can´t compile. Can you share your local patch? Maybe mine is malformed.

[ptr1337]

Still can´t compile. Can you share your local patch? Maybe mine is malformed.

https://paste.cachyos.org/p/db1b342.diff

tested on 6.1.0 with clang thinlto.
I will let a GCC kernel also running and report you.

[Mitch]

If your goal is the highest efficiency for the most workloads, it seems like Epp Balance Performance is the best all around choice for efficiency. What's interesting is that Power save is lower PPW, so unless you're working with a bad cooling solution or want minimum fan noise, you should stick with Epp balance performance.

Obviously other benchmarks may prove the p-state on demand will win more often, but just looking at what they posted here, that's my take.

My 6850u seems to rival my M1 air's efficiency sometimes (mostly multicore workloads), so I wonder if these patches could push it over that gap for some scenarios

[ptr1337]

@HD7950

Compiled well also with GCC.
Really check if WERROR is enabled or other patches are maybe conflicting to this.

[HD7950]

https://paste.cachyos.org/p/db1b342.diff

tested on 6.1.0 with clang thinlto.
I will let a GCC kernel also running and report you.

Still can't against 6.1.0 and GCC.

LD  .tmp_vmlinux.kallsyms1
ld: vmlinux.o: in function `show_energy_performance_available_preferences':
amd-pstate.c:(.text+0x7f9d57): undefined reference to `energy_perf_strings'
ld: amd-pstate.c:(.text+0x7f9d87): undefined reference to `energy_perf_strings'
ld: vmlinux.o: in function `store_energy_performance_preference':
amd-pstate.c:(.text+0x7f9f00): undefined reference to `energy_perf_strings'
ld: amd-pstate.c:(.text+0x7f9f23): undefined reference to `epp_values'
ld: vmlinux.o: in function `show_energy_performance_preference':
amd-pstate.c:(.text+0x7fa0e7): undefined reference to `energy_perf_strings'
make[1]: *** [scripts/Makefile.vmlinux:34: vmlinux] Error 1
make: *** [Makefile:1236: vmlinux] Error 2
A failure occurred in build().
Aborting... ​

This is weird as i could compile all previous epp patches. Thanks for your help anyways.

[HD7950]

@HD7950

Compiled well also with GCC.
Really check if WERROR is enabled or other patches are maybe conflicting to this.

I found the culprit: CONFIG_X86_INTEL_PSTATE was disabled on my personal kernel but it is needed by the AMD EPP driver now.

Thanks!

[ptr1337]

I found the culprit: CONFIG_X86_INTEL_PSTATE was disabled on my personal kernel but it is needed by the AMD EPP driver now.

Thanks!

Maybe report this to Perry Yuan.
Maybe the KCONFIG needs to be adjusted that it depends on this, if the build otherwise is failing. Happened cause he moved things to the intel_pstate.
But im not sure.

[mdedetrich]

I found the culprit: CONFIG_X86_INTEL_PSTATE was disabled on my personal kernel but it is needed by the AMD EPP driver now.

Thanks!

On a side note, if the pstate is now being generic between Intel and AMD shouldn't the config option be renamed to CONFIG_X86_PSTATE so its less misleading?

[andre30correia]

If your goal is the highest efficiency for the most workloads, it seems like Epp Balance Performance is the best all around choice for efficiency. What's interesting is that Power save is lower PPW, so unless you're working with a bad cooling solution or want minimum fan noise, you should stick with Epp balance performance.

Obviously other benchmarks may prove the p-state on demand will win more often, but just looking at what they posted here, that's my take.

My 6850u seems to rival my M1 air's efficiency sometimes (mostly multicore workloads), so I wonder if these patches could push it over that gap for some scenarios

My amd ryzen 7 5700u makes 9400 points in cinebench r23 even m2 cant beat that, using pstate driver in a cheap lenovo laptop (600 euros)