| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <aa2845b9-5e57-4df2-9c59-814eedd752dc@mailbox.org>
Date: Wed, 1 Feb 2023 18:35:04 +0000
From: Tor Vic <torvic9@...lbox.org>
To: Wyes Karny <wyes.karny@....com>,
Rafael J Wysocki <rafael@...nel.org>,
Huang Rui <ray.huang@....com>,
Jonathan Corbet <corbet@....net>,
Viresh Kumar <viresh.kumar@...aro.org>,
Mario.Limonciello@....com, Perry.Yuan@....com
Cc: linux-doc@...r.kernel.org, linux-kernel@...r.kernel.org,
linux-pm@...r.kernel.org, Bagas Sanjaya <bagasdotme@...il.com>,
santosh.shukla@....com, Len Brown <lenb@...nel.org>,
Robert Moore <robert.moore@...el.com>,
Borislav Petkov <bp@...en8.de>,
Ananth Narayan <ananth.narayan@....com>, gautham.shenoy@....com
Subject: Re: [PATCH v5 0/6] amd_pstate: Add guided autonomous mode support
On 01.02.23 06:58, Wyes Karny wrote:
> From ACPI spec[1] below 3 modes for CPPC can be defined:
> 1. Non autonomous: OS scaling governor specifies operating frequency/
> performance level through `Desired Performance` register and platform
> follows that.
> 2. Guided autonomous: OS scaling governor specifies min and max
> frequencies/ performance levels through `Minimum Performance` and
> `Maximum Performance` register, and platform can autonomously select an
> operating frequency in this range.
> 3. Fully autonomous: OS only hints (via EPP) to platform for the required
> energy performance preference for the workload and platform autonomously
> scales the frequency.
>
> Currently (1) is supported by amd_pstate as passive mode, and (3) is
> implemented by EPP support[2]. This change is to support (2).
>
> In guided autonomous mode the min_perf is based on the input from the
> scaling governor. For example, in case of schedutil this value depends
> on the current utilization. And max_perf is set to max capacity.
>
> To activate guided auto mode ``amd_pstate=guided`` command line
> parameter has to be passed in the kernel.
>
> Below are the results (normalized) of benchmarks with this patch:
> System: Genoa 96C 192T
> Kernel: 6.2.0-rc2 + EPP v12 + patch
> Scaling governor: schedutil
>
> ================ dbench comparisons ================
> dbench result comparison:
> Here results are throughput (MB/s)
> Clients: acpi-cpufreq amd_pst+passive amd_pst+guided
> 1 1.00 (0.00 pct) 1.01 (1.00 pct) 1.02 (2.00 pct)
> 2 1.07 (0.00 pct) 1.06 (-0.93 pct) 1.07 (0.00 pct)
> 4 1.68 (0.00 pct) 1.70 (1.19 pct) 1.72 (2.38 pct)
> 8 2.61 (0.00 pct) 2.68 (2.68 pct) 2.76 (5.74 pct)
> 16 4.16 (0.00 pct) 4.24 (1.92 pct) 4.53 (8.89 pct)
> 32 5.98 (0.00 pct) 6.17 (3.17 pct) 7.30 (22.07 pct)
> 64 8.67 (0.00 pct) 8.99 (3.69 pct) 10.71 (23.52 pct)
> 128 11.98 (0.00 pct) 12.52 (4.50 pct) 14.67 (22.45 pct)
> 256 15.73 (0.00 pct) 16.13 (2.54 pct) 17.81 (13.22 pct)
> 512 15.77 (0.00 pct) 16.32 (3.48 pct) 16.39 (3.93 pct)
> dbench power comparison:
> Clients: acpi-cpufreq amd_pst+passive amd_pst+guided
> 1 1.00 (0.00 pct) 1.00 (0.00 pct) 1.04 (4.00 pct)
> 2 0.99 (0.00 pct) 0.97 (-2.02 pct) 1.02 (3.03 pct)
> 4 0.98 (0.00 pct) 0.98 (0.00 pct) 1.02 (4.08 pct)
> 8 0.98 (0.00 pct) 0.99 (1.02 pct) 1.02 (4.08 pct)
> 16 0.99 (0.00 pct) 1.00 (1.01 pct) 1.04 (5.05 pct)
> 32 1.02 (0.00 pct) 1.02 (0.00 pct) 1.07 (4.90 pct)
> 64 1.05 (0.00 pct) 1.05 (0.00 pct) 1.11 (5.71 pct)
> 128 1.08 (0.00 pct) 1.08 (0.00 pct) 1.15 (6.48 pct)
> 256 1.12 (0.00 pct) 1.12 (0.00 pct) 1.20 (7.14 pct)
> 512 1.18 (0.00 pct) 1.17 (-0.84 pct) 1.26 (6.77 pct)
>
> ================ git-source comparisons ================
> git-source result comparison:
> Here results are throughput (compilations per 1000 sec)
> Threads: acpi-cpufreq amd_pst+passive amd_pst+guided
> 192 1.00 (0.00 pct) 0.93 (-7.00 pct) 1.00 (0.00 pct)
> git-source power comparison:
> Threads: acpi-cpufreq amd_pst+passive amd_pst+guided
> 192 1.00 (0.00 pct) 1.00 (0.00 pct) 0.96 (-4.00 pct)
>
> ================ kernbench comparisons ================
> kernbench result comparison:
> Here results are throughput (compilations per 1000 sec)
> Load: acpi-cpufreq amd_pst+passive amd_pst+guided
> 32 1.00 (0.00 pct) 1.01 (1.00 pct) 1.02 (2.00 pct)
> 48 1.26 (0.00 pct) 1.28 (1.58 pct) 1.25 (-0.79 pct)
> 64 1.39 (0.00 pct) 1.47 (5.75 pct) 1.43 (2.87 pct)
> 96 1.48 (0.00 pct) 1.50 (1.35 pct) 1.49 (0.67 pct)
> 128 1.29 (0.00 pct) 1.32 (2.32 pct) 1.33 (3.10 pct)
> 192 1.17 (0.00 pct) 1.20 (2.56 pct) 1.21 (3.41 pct)
> 256 1.17 (0.00 pct) 1.18 (0.85 pct) 1.20 (2.56 pct)
> 384 1.16 (0.00 pct) 1.17 (0.86 pct) 1.21 (4.31 pct)
> kernbench power comparison:
> Clients: acpi-cpufreq amd_pst+passive amd_pst+guided
> 32 1.00 (0.00 pct) 0.97 (-3.00 pct) 1.00 (0.00 pct)
> 48 0.87 (0.00 pct) 0.81 (-6.89 pct) 0.88 (1.14 pct)
> 64 0.81 (0.00 pct) 0.73 (-9.87 pct) 0.77 (-4.93 pct)
> 96 0.75 (0.00 pct) 0.74 (-1.33 pct) 0.75 (0.00 pct)
> 128 0.83 (0.00 pct) 0.79 (-4.81 pct) 0.83 (0.00 pct)
> 192 0.92 (0.00 pct) 0.88 (-4.34 pct) 0.92 (0.00 pct)
> 256 0.92 (0.00 pct) 0.88 (-4.34 pct) 0.92 (0.00 pct)
> 384 0.92 (0.00 pct) 0.88 (-4.34 pct) 0.92 (0.00 pct)
>
> ================ tbench comparisons ================
> tbench result comparison:
> Here results are throughput (MB/s)
> Clients: acpi-cpufreq amd_pst+passive amd_pst+guided
> 1 1.00 (0.00 pct) 0.70 (-30.00 pct) 1.37 (37.00 pct)
> 2 2.64 (0.00 pct) 1.39 (-47.34 pct) 2.70 (2.27 pct)
> 4 4.89 (0.00 pct) 2.75 (-43.76 pct) 5.28 (7.97 pct)
> 8 9.46 (0.00 pct) 5.42 (-42.70 pct) 10.22 (8.03 pct)
> 16 19.05 (0.00 pct) 10.42 (-45.30 pct) 19.94 (4.67 pct)
> 32 37.50 (0.00 pct) 20.23 (-46.05 pct) 36.87 (-1.68 pct)
> 64 61.24 (0.00 pct) 43.08 (-29.65 pct) 62.96 (2.80 pct)
> 128 67.16 (0.00 pct) 69.08 (2.85 pct) 67.34 (0.26 pct)
> 256 154.59 (0.00 pct) 162.33 (5.00 pct) 156.78 (1.41 pct)
> 512 154.02 (0.00 pct) 156.74 (1.76 pct) 153.48 (-0.35 pct)
> tbench power comparison:
> Clients: acpi-cpufreq amd_pst+passive amd_pst+guided
> 1 1.00 (0.00 pct) 0.97 (-3.00 pct) 1.08 (8.00 pct)
> 2 1.04 (0.00 pct) 0.97 (-6.73 pct) 1.11 (6.73 pct)
> 4 1.12 (0.00 pct) 0.99 (-11.60 pct) 1.18 (5.35 pct)
> 8 1.25 (0.00 pct) 1.04 (-16.80 pct) 1.31 (4.80 pct)
> 16 1.53 (0.00 pct) 1.13 (-26.14 pct) 1.58 (3.26 pct)
> 32 2.01 (0.00 pct) 1.36 (-32.33 pct) 2.03 (0.99 pct)
> 64 2.58 (0.00 pct) 2.14 (-17.05 pct) 2.61 (1.16 pct)
> 128 2.80 (0.00 pct) 2.81 (0.35 pct) 2.81 (0.35 pct)
> 256 3.39 (0.00 pct) 3.43 (1.17 pct) 3.42 (0.88 pct)
> 512 3.44 (0.00 pct) 3.44 (0.00 pct) 3.44 (0.00 pct)
>
> Note: this series is based on top of EPP v12 [3] series
>
> Change log:
>
> v4 -> v5:
> - Rebased on top of EPP v12 series
> - Addressed comments form Mario regarding documentation
> - Picked up RB flags from Mario and Bagas Sanjaya
>
> v3 -> v4:
> - Fixed active mode low frequency issue reported by Peter Jung and Tor Vic
> - Documentation modification suggested by Bagas Sanjaya
>
> v2 -> v3:
> - Addressed review comments form Mario.
> - Picked up RB tag from Mario.
> - Rebase on top of EPP v11 [3].
>
> v1 -> v2:
> - Fix issue with shared mem systems.
> - Rebase on top of EPP series.
>
> [1]: https://uefi.org/sites/default/files/resources/ACPI_6_3_final_Jan30.pdf
> [2]: https://lore.kernel.org/lkml/20221110175847.3098728-1-Perry.Yuan@amd.com/
> [3]: https://lore.kernel.org/linux-pm/20230131090016.3970625-1-perry.yuan@amd.com/
>
> Wyes Karny (6):
> acpi: cppc: Add min and max perf reg writing support
> acpi: cppc: Add auto select register read/write support
> cpufreq: amd_pstate: Add guided autonomous mode
> Documentation: amd_pstate: Move amd_pstate param to alphabetical order
> cpufreq: amd_pstate: Add guided mode control support via sysfs
> Documentation: amd_pstate: Update amd_pstate status sysfs for guided
>
> .../admin-guide/kernel-parameters.txt | 41 ++--
> Documentation/admin-guide/pm/amd-pstate.rst | 34 +++-
> drivers/acpi/cppc_acpi.c | 121 +++++++++++-
> drivers/cpufreq/amd-pstate.c | 183 +++++++++++++-----
> include/acpi/cppc_acpi.h | 11 ++
> include/linux/amd-pstate.h | 2 +
> 6 files changed, 311 insertions(+), 81 deletions(-)
>
I tested "active" mode on a Zen2, using EPP v12 and this series on top.
Here is the output of 'cpupower frequency-info' run as root under full load:
analyzing CPU 0:
driver: amd_pstate_epp
CPUs which run at the same hardware frequency: 0
CPUs which need to have their frequency coordinated by software: 0
maximum transition latency: Cannot determine or is not supported.
hardware limits: 550 MHz - 4.67 GHz
available cpufreq governors: performance powersave
current policy: frequency should be within 550 MHz and 4.67 GHz.
The governor "powersave" may decide which speed to use
within this range.
current CPU frequency: Unable to call hardware
current CPU frequency: 4.18 GHz (asserted by call to kernel)
boost state support:
Supported: yes
Active: yes
Boost States: 0
Total States: 3
Pstate-P0: 3800MHz
Pstate-P1: 2800MHz
Pstate-P2: 2200MHz
Changing EPP mode via sysfs works.
----
Live-switching to "guided" mode via sysfs also seems to work fine:
analyzing CPU 0:
driver: amd-pstate
CPUs which run at the same hardware frequency: 0
CPUs which need to have their frequency coordinated by software: 0
maximum transition latency: 20.0 us
hardware limits: 550 MHz - 4.67 GHz
available cpufreq governors: ondemand powersave performance schedutil
current policy: frequency should be within 550 MHz and 4.67 GHz.
The governor "ondemand" may decide which speed to use
within this range.
current CPU frequency: Unable to call hardware
current CPU frequency: 3.71 GHz (asserted by call to kernel)
boost state support:
Supported: yes
Active: yes
AMD PSTATE Highest Performance: 166. Maximum Frequency: 4.67 GHz.
AMD PSTATE Nominal Performance: 135. Nominal Frequency: 3.80 GHz.
AMD PSTATE Lowest Non-linear Performance: 62. Lowest Non-linear
Frequency: 1.74 GHz.
AMD PSTATE Lowest Performance: 20. Lowest Frequency: 550 MHz.
----
Seems to work fine so far.
Hope this helps.
I can test more in detail and give you a Tested-by tag if wanted.
Thanks,
Tor Vic
Powered by blists - more mailing lists