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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B8C85C77B76 for ; Fri, 14 Apr 2023 15:21:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230462AbjDNPVJ (ORCPT ); Fri, 14 Apr 2023 11:21:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40974 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229866AbjDNPVH (ORCPT ); Fri, 14 Apr 2023 11:21:07 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 98F4810C2; Fri, 14 Apr 2023 08:21:05 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 8E28A2F4; Fri, 14 Apr 2023 08:21:49 -0700 (PDT) Received: from [10.57.19.153] (unknown [10.57.19.153]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 02D153F6C4; Fri, 14 Apr 2023 08:21:02 -0700 (PDT) Message-ID: <6022d391-9ae8-2bb4-0f81-2c99466dc556@arm.com> Date: Fri, 14 Apr 2023 16:21:01 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.9.0 Subject: Re: [PATCH V3] thermal/core/power_allocator: avoid thermal cdev can not be reset Content-Language: en-US To: Daniel Lezcano Cc: Di Shen , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, xuewen.yan@unisoc.com, jeson.gao@unisoc.com, zhanglyra@gmail.com, orsonzhai@gmail.com, rui.zhang@intel.com, amitk@kernel.org, rafael@kernel.org, Di Shen References: <20230320095620.7480-1-di.shen@unisoc.com> <6055bc39-5c00-d12f-b5c3-fa21a9649d63@arm.com> <637a3bb1-ba1c-e707-01b7-06c1358583ca@linaro.org> <6aad180f-410c-5b11-b30b-c7bc02cbe054@linaro.org> From: Lukasz Luba In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/14/23 16:06, Daniel Lezcano wrote: > On 14/04/2023 16:18, Lukasz Luba wrote: >> >> >> On 4/14/23 12:12, Daniel Lezcano wrote: >>> On 13/04/2023 10:40, Di Shen wrote: >>>> We have discussed this question in patch-v1: >>>> https://lore.kernel.org/all/f6aaa5f1-495d-a158-14d8-ddb2bffbd9c2@arm.com/ >>>> >>>> Simply put, we use the trip_temp in the Android System; set different >>>> trip_temp for thermal control of different scenarios. >>> >>> The changes are dealing with the trip points and trying to detect the >>> threshold. That part should be handled in the thermal core or thermal >>> trip side, not in the governor. >>> >>> AFAICT, if a trip point is changed, then the power allocator should >>> be reset, including the cdev state. >>> >>> It would be more convenient to add an ops to the governor ops >>> structure to reset the governor and then call it when a trip point is >>> changed in thermal_zone_set_trip() >>> >>> >> >> Sounds reasonable to have a proper API and fwk handling this corner >> case scenario. >> Although, if there is a need for a 'easy-to-backport' fix for IPA only, >> I agree with this patch, since it's straight forward to put in some >> Android kernel. We can later fix the framework to handle this properly. >> Anyway, both ways are OK to me. > > Unfortunately, we can not do the maintenance of the Linux kernel based > on an 'easy-to-backport' policy to Android. > > This patch could be applied from-list to Android as a hotfix. But for > Linux the fix should be more elaborated. One solution is to add a > 'reset' ops and call it from the trip point update function. Fair enough. > > Did you double check the issue is not impacting the other governors too ? No, unfortunately, I haven't checked other governors.