From: "Zhang, Rui" <rui.zhang@intel.com>
To: Andreas Mohr <andi@lisas.de>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Cc: "R, Durgadoss" <durgadoss.r@intel.com>,
"peter@piie.net" <peter@piie.net>,
"lenb@kernel.org" <lenb@kernel.org>
Subject: RE: thermal governor: does it actually work??
Date: Fri, 15 Feb 2013 09:47:07 +0000 [thread overview]
Message-ID: <744357E9AAD1214791ACBA4B0B90926329ED72@SHSMSX101.ccr.corp.intel.com> (raw)
In-Reply-To: <20130214153255.GA5033@rhlx01.hs-esslingen.de>
> -----Original Message-----
> From: Andreas Mohr [mailto:andi@lisas.de]
> Sent: Thursday, February 14, 2013 11:33 PM
> To: linux-kernel@vger.kernel.org
> Cc: R, Durgadoss; Zhang, Rui; peter@piie.net
> Subject: thermal governor: does it actually work??
> Importance: High
>
> For me after having loaded acerhdf the fan never stops (with kernelmode
> active), despite staying safely below trip point
> (acerhdf_set_cur_state() actually never gets called).
Please attach the output of
"grep . /sys/class/thermal/thermal_zone*/cdev*/*"?
> And AFAIR in a 3.2.0 kernel acerhdf fan operation seemed to just work
> (i.e., no fan for low temps, from the beginning).
> Needless to say 3.2.0 didn't even feature all the modern thermal
> governor crapyard yet ;) (ok, well, it's more complex but it's also a
> very nice environment capability)
>
> 3.8-rc7:
> CONFIG_ACPI_THERMAL=m
> CONFIG_THERMAL=m
> CONFIG_THERMAL_HWMON=y
> CONFIG_THERMAL_DEFAULT_GOV_STEP_WISE=y
> # CONFIG_THERMAL_DEFAULT_GOV_FAIR_SHARE is not set #
> CONFIG_THERMAL_DEFAULT_GOV_USER_SPACE is not set CONFIG_FAIR_SHARE=y
> CONFIG_STEP_WISE=y # CONFIG_USER_SPACE is not set # CONFIG_CPU_THERMAL
> is not set
>
>
>
> Terminology in this area seems to be quite a bit off, too, at several
> docs places, at least according to my understanding:
>
> e.g. drivers/thermal/step_wise.c has the following comment:
>
> /**
> * step_wise_throttle - throttles devices associated with the given
> zone
> * @tz - thermal_zone_device
> * @trip - the trip point
> * @trip_type - type of the trip point
> *
> * Throttling Logic: This uses the trend of the thermal zone to
> * throttle.
> * If the thermal zone is 'heating up' this throttles all the cooling
> * devices associated with the zone and its particular trip point, by
> * one
> * step. If the zone is 'cooling down' it brings back the performance
> of
> * the devices by one step.
>
>
>
> if ... heating up ... throttles ...
> Sorry, but at least for P4 clockmod stuff (or some such), throttle
> states (P1...P8 IIRC) meant that the CPU operation was *reduced*, i.e.
> with pause intervals.
For processors, surely you are right.
> And the translation of throttle clearly says that it does go that way
> and not the other way...
> (yes, you managed to confuse me that much that I even had to look up
> things to verify)
>
The question is that if we can also call it "throttle" when reducing the device performance to generate less heat.
I do not have a clear answer for this as I'm not a native English speaker.
And what you're saying here may be right.
Surely I can generate a patch to rename it if throttle can't be used in that way.
Len,
What's your idea on this?
Thanks,
rui
> ... cooling down ... brings back ...
> This should certainly be worded "reduces" or some such.
>
> So, any idea why I'm missing callbacks in acerhdf (if that is what I'm
> supposed to expect to happen)?
> Kernel bug, .config mistake, missing/wrong user-side setup?
>
> Needless to say if kernel bug this ought to be fixed pre-3.8 ideally.
>
> Thanks,
>
> Andreas Mohr
next prev parent reply other threads:[~2013-02-15 9:47 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-02-14 15:32 thermal governor: does it actually work?? Andreas Mohr
2013-02-15 9:47 ` Zhang, Rui [this message]
2013-02-15 15:49 ` Andreas Mohr
2013-02-16 21:08 ` Alexander Lam
2013-02-16 21:47 ` Borislav Petkov
2013-02-17 2:43 ` Peter Feuerer
2013-02-17 14:09 ` Borislav Petkov
2013-02-17 15:41 ` Peter Feuerer
2013-02-18 13:50 ` Borislav Petkov
2013-02-18 16:47 ` Peter Feuerer
2013-02-19 14:51 ` Zhang Rui
2013-02-19 15:05 ` Borislav Petkov
2013-02-19 15:27 ` Zhang Rui
[not found] ` <CACWwPisqpmLjiqEh+J2DjnEtNObmmA0w=qMQYTgBsb6Ntad7Pw@mail.gmail.com>
[not found] ` <744357E9AAD1214791ACBA4B0B90926329F98E@SHSMSX101.ccr.corp.intel.com>
[not found] ` <CACWwPit=xxeeCW1+jfxE8eww+P545B5xebh3YT2yE78zcsqSMg@mail.gmail.com>
2013-02-18 20:33 ` Alexander Lam
2013-02-19 14:53 ` Zhang Rui
2013-02-19 15:35 ` Zhang Rui
2013-02-22 5:33 ` Peter Feuerer
2013-02-22 11:15 ` Borislav Petkov
2013-02-23 19:20 ` [PATCH] acerhdf: Fix fan activation with new thermal governor Borislav Petkov
2013-02-24 11:28 ` Borislav Petkov
2013-02-24 11:42 ` Peter Feuerer
2013-02-24 12:09 ` Borislav Petkov
2013-02-24 12:59 ` Borislav Petkov
2013-02-25 3:06 ` Zhang Rui
2013-02-25 10:20 ` Borislav Petkov
2013-02-25 10:36 ` Peter Feuerer
2013-02-24 14:34 ` Borislav Petkov
2013-02-25 3:21 ` Zhang Rui
2013-02-25 10:25 ` Borislav Petkov
2013-02-25 12:16 ` Borislav Petkov
2013-03-04 13:34 ` Borislav Petkov
2013-03-04 19:25 ` Andreas Mohr
2013-03-05 21:59 ` Andreas Mohr
2013-03-06 3:47 ` Zhang Rui
2013-03-06 7:00 ` Borislav Petkov
2013-03-06 7:30 ` Zhang Rui
2013-03-06 7:36 ` Borislav Petkov
2013-03-07 20:17 ` Peter Feuerer
2013-03-07 20:27 ` Borislav Petkov
2013-02-25 3:01 ` Zhang Rui
2013-02-25 2:58 ` Zhang Rui
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=744357E9AAD1214791ACBA4B0B90926329ED72@SHSMSX101.ccr.corp.intel.com \
--to=rui.zhang@intel.com \
--cc=andi@lisas.de \
--cc=durgadoss.r@intel.com \
--cc=lenb@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=peter@piie.net \
/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;
as well as URLs for NNTP newsgroup(s).