From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CDA1FC2BB1D for ; Tue, 14 Apr 2020 21:51:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B13412078A for ; Tue, 14 Apr 2020 21:51:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2440950AbgDNVv2 (ORCPT ); Tue, 14 Apr 2020 17:51:28 -0400 Received: from mga06.intel.com ([134.134.136.31]:57796 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2440819AbgDNVv0 (ORCPT ); Tue, 14 Apr 2020 17:51:26 -0400 IronPort-SDR: vZU0oqJXCsEvUa/EtJCIfj1Vo16Ek2XpihzCVrTLA5s+3D5jzjjEnwZEWC0X1sxp8F9MnKNLzI hFXw4GXDwwjQ== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Apr 2020 14:51:24 -0700 IronPort-SDR: ij8iqHgZZGRON/acdZ34Z8oe1de2h0YuaZUoV5nkBqf5XAAASINM7Rc6Fba1Xl8axQDbfmFBtB EdajjSl5EfwQ== X-IronPort-AV: E=Sophos;i="5.72,384,1580803200"; d="scan'208";a="271529999" Received: from spandruv-mobl.amr.corp.intel.com ([10.134.69.31]) by orsmga002-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Apr 2020 14:51:23 -0700 Message-ID: Subject: Re: [PATCH 3/3] x86/mce/therm_throt: allow disabling the thermal vector altogether From: Srinivas Pandruvada To: "Jason A. Donenfeld" Cc: Borislav Petkov , LKML , linux-edac@vger.kernel.org, X86 ML , Arnd Bergmann , bberg@redhat.com, Tony Luck Date: Tue, 14 Apr 2020 14:51:22 -0700 In-Reply-To: References: <20200407063345.4484-1-Jason@zx2c4.com> <20200407063345.4484-3-Jason@zx2c4.com> <0e189a4fe1e69b08afc859ce83623a0e5ea0c08b.camel@linux.intel.com> <4b75ec34ccff5abdc0b1c04a5ac39455ddd4f49b.camel@linux.intel.com> <20200414202328.GK31763@zn.tnic> <81359df9983fb70bd40ddb3be9090e5521294529.camel@linux.intel.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.34.2 (3.34.2-1.fc31) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-edac-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-edac@vger.kernel.org On Tue, 2020-04-14 at 15:07 -0600, Jason A. Donenfeld wrote: > On Tue, Apr 14, 2020 at 2:49 PM Srinivas Pandruvada > wrote: > > On Tue, 2020-04-14 at 22:23 +0200, Borislav Petkov wrote: > > > + Tony. > > > > > > On Tue, Apr 14, 2020 at 01:41:08PM -0600, Jason A. Donenfeld > > > wrote: > > > > Generally it is desirable, and extremely common too. This > > > > thermal > > > > code > > > > -- which mostly functions to print some messages into kmsg -- > > > > is > > > > very > > > > verbose. This is not something I want to compile into smaller > > > > systems. > > > > This is the reason why kconfig has options in the first place. > > > > I'm > > > > not > > > > sure yet-another boottime flag makes sense for this. > > > > > > I don't mind making the already existing option selectable and > > > leaving > > > it default y, i.e., keeping the current situation by default. And > > > people > > > who want to disable it, can then do so. > > > > > > I do mind to having yet another config option though. No thanks - > > > they're already too many. > > > > > > So it should be an all or nothing thing. > > > > > > Poking quickly at that and > > > drivers/thermal/intel/x86_pkg_temp_thermal.c, > > > all those things do is report trip points. therm_throt reports > > > how > > > long > > > the hw throttled due to hitting a trip point, etc. > > > > > > IINM, of course so please correct me if I'm missing anything. > > > > > > But if not and this all is only for reporting and doesn't have > > > any > > > detrimental effects on the hardware when missing from the system, > > > then I > > > guess we could make CONFIG_X86_THERMAL_VECTOR user-selectable. > > > > We can make user selectable > > > > These drivers are used for reporting only. > > User space can select a trip temperature via x86_pkg_temp and get > > notification via uevent to start additional cooling system > > (additional > > I didn't see any uevent stuff. Is this part of out-of-tree modules or > proprietary code that's hooking into those EXPORT_SYMBOL (non-GPL) > exports? This is not out of tree. This is x86_pkg_temp driver as part of thermal subsystem, and thermal_zone_device_update() user space governor issues uevent. But those are different modifiable thresholds not the high/low temperature thresholds. > > > fans, liquid coooling etc), so that processor don't have to go self > > throttling mode. Self throttling depending on processor series and > > firmware can be very aggressive. > > In client systems thermald will set a temperature and starts power > > control once it reaches passive temperature limit. But it can > > function > > without x86_pkg_temp also, so even if user disables thermal > > reporting > > it can still function. > > The 2/3 patch may be interesting as well to you. This removes the > expensive work queue management stuff if the option is deselected, > since all those workqueues do is print messages to kmsg, while > retaining the rest of the infra.