Re: [PATCH v6 0/6] AMD Pstate Driver Core Performance Boost

[Gautham R. Shenoy]

Hello Perry,

On Mon, Mar 18, 2024 at 06:11:07PM +0800, Perry Yuan wrote:
> Hi all,
> The patchset series add core performance boost feature for AMD pstate
> driver including passisve ,guide and active mode support.
> 
> User can change core frequency boost control with a new sysfs entry:
> 
> "/sys/devices/system/cpu/amd_pstate/cpb_boost"
> 
> The legancy boost interface has been removed due to the function
> conflict with new cpb_boost which can support all modes.
> 
> 1). enable core boost:

You meant disable core boost here.

> $ sudo bash -c "echo 0 > /sys/devices/system/cpu/amd_pstate/cpb_boost"
> $ lscpu -ae
> CPU NODE SOCKET CORE L1d:L1i:L2:L3 ONLINE    MAXMHZ   MINMHZ      MHZ
>   0    0      0    0 0:0:0:0          yes 4201.0000 400.0000 2983.578
>   1    0      0    1 1:1:1:0          yes 4201.0000 400.0000 2983.578
>   2    0      0    2 2:2:2:0          yes 4201.0000 400.0000 2583.855
>   3    0      0    3 3:3:3:0          yes 4201.0000 400.0000 2983.578
>   4    0      0    4 4:4:4:0          yes 4201.0000 400.0000 2983.578
> 
> 2). disabble core boost:

.. and enable core boost here.

> $ sudo bash -c "echo 1 > /sys/devices/system/cpu/amd_pstate/cpb_boost"
> $ lscpu -ae
>    0    0      0    0 0:0:0:0          yes 5759.0000 400.0000 2983.578
>   1    0      0    1 1:1:1:0          yes 5759.0000 400.0000 2983.578
>   2    0      0    2 2:2:2:0          yes 5759.0000 400.0000 2983.578
>   3    0      0    3 3:3:3:0          yes 5759.0000 400.0000 2983.578
>   4    0      0    4 4:4:4:0          yes 5759.0000 400.0000 2983.578
> 
> 
> The patches have been tested with the AMD 7950X processor and many users
> would like to get core boost control enabled for power saving.
> 
> If you would like to test this patchset, it needs to apply the patchset
> based on below one latest version patchset.
> https://lore.kernel.org/lkml/cover.1710754409.git.perry.yuan@xxxxxxx/

Thanks. Will test this on EPYC platforms. 
>
> Perry.

--
Thanks and Regards
gautham.

> 
> Changes from v4:
>  * drop the legacy boost remove patch, let us keep the legacy interface
>    in case some applications break.
>  * rebase to linux-pm/bleeding-edge branch
>  * rework the patchset base on [PATCH v8 0/8] AMD Pstate Fixes And
>    Enhancements which has some intial work done there.
> 
> Changes from v4:
>  * move MSR_K7_HWCR_CPB_DIS_BIT into msr-index.h
>  * pick RB flag from Gautham R. Shenoy
>  * add Cc Oleksandr Natalenko <oleksandr@xxxxxxxxxxxxxx>
>  * rebase to latest linux-pm/bleeding-edge branch
>  * rebase the patch set on top of [PATCH v7 0/6] AMD Pstate Fixes And Enhancements
>  * update  [PATCH v7 2/6] to use MSR_K7_HWCR_CPB_DIS_BIT 
> 
> Changes from v3:
>  * rebased to linux-pm/bleeding-edge v6.8
>  * rename global to amd_pstate_global_params(Oleksandr Natalenko)
>  * remove comments for boot_supported in amd_pstate.h
>  * fix the compiler warning for amd-pstate-ut.ko
>  * use for_each_online_cpu in cpb_boost_store which fix the null pointer
>    error during testing
>  * fix the max frequency value to be KHz when cpb boost disabled(Gautham R. Shenoy)
> 
> Changes from v2:
>  * move global struct to amd-pstate.h
>  * fix the amd-pstate-ut with new cpb control interface
> 
> Changes from v1:
>  * drop suspend/resume fix patch 6/7 because of the fix should be in
>    another fix series instead of CPB feature
>  * move the set_boost remove patch to the last(Mario)
>  * Fix commit info with "Closes:" (Mario)
>  * simplified global.cpb_supported initialization(Mario)
>  * Add guide mode support for CPB control
>  * Fixed some Doc typos and add guide mode info to Doc as well.
> 
> v1: https://lore.kernel.org/all/cover.1706255676.git.perry.yuan@xxxxxxx/
> v2: https://lore.kernel.org/lkml/cover.1707047943.git.perry.yuan@xxxxxxx/
> v3: https://lore.kernel.org/lkml/cover.1707297581.git.perry.yuan@xxxxxxx/
> v4: https://lore.kernel.org/lkml/cover.1710322310.git.perry.yuan@xxxxxxx/
> v5: https://lore.kernel.org/lkml/cover.1710473712.git.perry.yuan@xxxxxxx/
> 
> 
> Perry Yuan (6):
>   cpufreq: acpi: move MSR_K7_HWCR_CPB_DIS_BIT into msr-index.h
>   cpufreq: amd-pstate: initialize new core precision boost state
>   cpufreq: amd-pstate: implement cpb_boost sysfs entry for boost control
>   cpufreq: amd-pstate: fix the MSR highest perf will be reset issue
>     while cpb boost off
>   Documentation: cpufreq: amd-pstate: introduce the new cpu boost
>     control method
>   cpufreq: amd-pstate-ut: support new cpb boost control interface
> 
>  Documentation/admin-guide/pm/amd-pstate.rst |  11 ++
>  arch/x86/include/asm/msr-index.h            |   2 +
>  drivers/cpufreq/acpi-cpufreq.c              |   2 -
>  drivers/cpufreq/amd-pstate-ut.c             |   2 +-
>  drivers/cpufreq/amd-pstate.c                | 143 ++++++++++++++++++--
>  include/linux/amd-pstate.h                  |  13 ++
>  6 files changed, 160 insertions(+), 13 deletions(-)
> 
> -- 
> 2.34.1
>