From: Thomas Renninger <trenn@suse.de>
To: Rafael Wysocki <rafael@kernel.org>
Cc: linux-pm@vger.kernel.org
Subject: Re: [PATCH] x86: Do not override performance EPB MSR value on servers
Date: Mon, 08 Apr 2019 10:51:53 +0200 [thread overview]
Message-ID: <3028388.0SNZMY0NmP@house> (raw)
In-Reply-To: <36183132.7cOCK0nhyl@house>
On Monday, April 8, 2019 10:46:46 AM CEST Thomas Renninger wrote:
> It is about this kernel message showing up on quite a lot servers:
> [ 0.072652] ENERGY_PERF_BIAS: Set to 'normal', was 'performance'
> [ 0.076003] ENERGY_PERF_BIAS: View and update with
> x86_energy_perf_policy(8)
>
> With this patch the EPB value is not overridden anymore on systems
> which expose themselves as appliance or enterprise server via ACPI
> perferred profile variable.
>
> Signed-off-by: trenn@suse.de
The patch has successfully been tested on top of Rafeals latest EPB
fixes:
[PATCH 0/2] PM / arch: x86: MSR_IA32_ENERGY_PERF_BIAS handling fixes and sysfs
i/f
EPB value is now successfully and correctly restored after CPU off-/onlining
It can be set back to performance value if kernel set it to normal and this
value also survives CPU off-/onlining.
Still the kernel should not override the performance value on servers, so
it would be nice to see the patch applied.
Once applied, I may send a patch based on code before EPB changes similar to
this for stable kernels. There it is even more urgent, due to the wrong
unconditional setting to "normal" value after CPU off-/onlining.
I tested the patch to make sure the preferred value is considered and it
works.
Thomas
next prev parent reply other threads:[~2019-04-08 8:51 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-08 8:46 [PATCH] x86: Do not override performance EPB MSR value on servers Thomas Renninger
2019-04-08 8:51 ` Thomas Renninger [this message]
2019-04-16 21:31 ` Rafael J. Wysocki
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=3028388.0SNZMY0NmP@house \
--to=trenn@suse.de \
--cc=linux-pm@vger.kernel.org \
--cc=rafael@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox