From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758524Ab3BSPfc (ORCPT ); Tue, 19 Feb 2013 10:35:32 -0500 Received: from mga11.intel.com ([192.55.52.93]:52000 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758393Ab3BSPfb (ORCPT ); Tue, 19 Feb 2013 10:35:31 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.84,696,1355126400"; d="scan'208";a="289093530" Message-ID: <1361288123.2323.29.camel@rzhang1-mobl4> Subject: Re: thermal governor: does it actually work?? From: Zhang Rui To: Andreas Mohr Cc: linux-kernel@vger.kernel.org, Durgadoss R , peter@piie.net Date: Tue, 19 Feb 2013 23:35:23 +0800 In-Reply-To: <20130214153255.GA5033@rhlx01.hs-esslingen.de> References: <20130214153255.GA5033@rhlx01.hs-esslingen.de> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2013-02-14 at 16:32 +0100, Andreas Mohr wrote: > 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). BTW, could you please check if this one fixes the problem for you? http://git.kernel.org/?p=linux/kernel/git/rzhang/linux.git;a=commit;h=b8bb6cb999858043489c1ddef08eed2127559169 thanks, rui > 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. > 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) > > ... 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