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=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 86375C43331 for ; Sun, 10 Nov 2019 16:49:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5270F2080F for ; Sun, 10 Nov 2019 16:49:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573404569; bh=IaXEgDreolxql+OnLwDbTike/4OS7jtVgJGn4rCxdyQ=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=xvXc28NNIirZWWMLoY4a4bXcbqDe8QDD3MG1hGo5WIWAOJc2F7yIGyFr/bo63mnOS rQ8ICVAy8fqPmO1ocz7RHB1xmVoYWR0K6ugbhSjcVtvIP3md3IIjDB2aAekgUXskwD 2snaEzGOQpa5vaNtc/aG3n+OjNE1IbOhKIBtrfs0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726957AbfKJQt1 (ORCPT ); Sun, 10 Nov 2019 11:49:27 -0500 Received: from mail-oi1-f194.google.com ([209.85.167.194]:37905 "EHLO mail-oi1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726616AbfKJQt1 (ORCPT ); Sun, 10 Nov 2019 11:49:27 -0500 Received: by mail-oi1-f194.google.com with SMTP id a14so9502040oid.5; Sun, 10 Nov 2019 08:49:26 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=hF4gcvRLoFI5GEISKxekVetVmnJbmxGGWorHkggFZtA=; b=sXVjINRN6dWhI1jhVw8iTzaoBt/EPUnV57oeUIVJaRdcEmnSNIDufKV0S0RCdGu0HH 5J+mzPvPYN6SPsPphDDhY/Q8gjftn1NOgJDBMUOYKq4sVEegCq+PcXA3P7li3FpN6HJW zIgkm0CzkYGvNH524H2AsU/WDd/EUYnZFSqBU2yJABgRkl5Lw4PQjBngetigI2dBNMxk A3HUmb8ut/oPwQpK2JbBG9Y7uE3fcVcUS0XgKzPzdymyizsm4KmtfRW34o1Ox2E2T7MX IV5eeccJZeSgD0uU6mA4M8d0NGhC1BRXBTD5DbiTPLKRXjH4aGUFKtY4cmkFtBLq3/IM 88wg== X-Gm-Message-State: APjAAAW67e0RqwhcNv10TaUyWUMdBl0PIl4w4fQhspffBHVsEdolzWuF LKlpbjNiBjdjmcKqJeMiYUwV5CQ1xB+v/Rb0H7s= X-Google-Smtp-Source: APXvYqwocqyArLhnCTnNgpL3WAP1SlQIayKttbriLtJ/Bn6+a1Gk2C0XMzoFr6MqDTM+6calLN3MF5baVVqrCEI7law= X-Received: by 2002:aca:d4c6:: with SMTP id l189mr19566038oig.68.1573404565469; Sun, 10 Nov 2019 08:49:25 -0800 (PST) MIME-Version: 1.0 References: <20191030075141.1039-1-daniel.lezcano@linaro.org> <20191030075141.1039-2-daniel.lezcano@linaro.org> <143021538.HHUP3Pj7i7@kreacher> <9dfe3bd3-1903-4dc4-0605-27cc867d87ad@linaro.org> <59f10030-cef0-4d75-5135-9d0590385fda@linaro.org> In-Reply-To: <59f10030-cef0-4d75-5135-9d0590385fda@linaro.org> From: "Rafael J. Wysocki" Date: Sun, 10 Nov 2019 17:49:10 +0100 Message-ID: Subject: Re: [PATCH V6 2/3] cpuidle: play_idle: Specify play_idle with an idle state To: Daniel Lezcano Cc: "Rafael J. Wysocki" , "Rafael J. Wysocki" , Mathieu Poirier , Ingo Molnar , Peter Zijlstra , Linux PM , Linux Kernel Mailing List , Ulf Hansson Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 8, 2019 at 2:33 PM Daniel Lezcano wrote: > > On 08/11/2019 11:56, Rafael J. Wysocki wrote: > > On Fri, Nov 8, 2019 at 11:47 AM Daniel Lezcano > > wrote: > >> > >> On 08/11/2019 02:20, Rafael J. Wysocki wrote: > >>> On Wednesday, October 30, 2019 8:51:40 AM CET Daniel Lezcano wrote: > >>>> Currently, the play_idle function does not allow to tell which idle > >>>> state we want to go. Improve this by passing the idle state as > >>>> parameter to the function. > >>>> > >>>> Export cpuidle_find_deepest_state() symbol as it is used from the > >>>> intel_powerclamp driver as a module. > >>>> > >>>> There is no functional changes, the cpuidle state is the deepest one. > >>>> > >>>> Signed-off-by: Daniel Lezcano > >>>> Acked-by: Mathieu Poirier > >>>> Reviewed-by: Ulf Hansson > >>>> --- > >>>> V6: > >>>> - Change variable name 'state' -> 'index': > >>>> https://lkml.org/lkml/2019/10/28/874 > >>>> V4: > >>>> - Add EXPORT_SYMBOL_GPL(cpuidle_find_deepest_state) for the > >>>> intel_powerclamp driver when this one is compiled as a module > >>>> V3: > >>>> - Add missing cpuidle.h header > >>>> --- > >>>> drivers/cpuidle/cpuidle.c | 1 + > >>>> drivers/powercap/idle_inject.c | 4 +++- > >>>> drivers/thermal/intel/intel_powerclamp.c | 4 +++- > >>>> include/linux/cpu.h | 2 +- > >>>> kernel/sched/idle.c | 4 ++-- > >>>> 5 files changed, 10 insertions(+), 5 deletions(-) > >>>> > >>>> diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c > >>>> index 18523ea6b11b..b871fc2e8e67 100644 > >>>> --- a/drivers/cpuidle/cpuidle.c > >>>> +++ b/drivers/cpuidle/cpuidle.c > >>>> @@ -126,6 +126,7 @@ int cpuidle_find_deepest_state(void) > >>>> > >>>> return find_deepest_state(drv, dev, UINT_MAX, 0, false); > >>>> } > >>>> +EXPORT_SYMBOL_GPL(cpuidle_find_deepest_state); > >>> > >>> That doesn't appear to be really necessary to me. > >>> > >>>> > >>>> #ifdef CONFIG_SUSPEND > >>>> static void enter_s2idle_proper(struct cpuidle_driver *drv, > >>>> diff --git a/drivers/powercap/idle_inject.c b/drivers/powercap/idle_inject.c > >>>> index cd1270614cc6..233c878cbf46 100644 > >>>> --- a/drivers/powercap/idle_inject.c > >>>> +++ b/drivers/powercap/idle_inject.c > >>>> @@ -38,6 +38,7 @@ > >>>> #define pr_fmt(fmt) "ii_dev: " fmt > >>>> > >>>> #include > >>>> +#include > >>>> #include > >>>> #include > >>>> #include > >>>> @@ -138,7 +139,8 @@ static void idle_inject_fn(unsigned int cpu) > >>>> */ > >>>> iit->should_run = 0; > >>>> > >>>> - play_idle(READ_ONCE(ii_dev->idle_duration_us)); > >>>> + play_idle(READ_ONCE(ii_dev->idle_duration_us), > >>>> + cpuidle_find_deepest_state()); > >>> > >>> The next patch changes this again and I'm not sure why this intermediate > >>> change is useful. > >>> > >>>> } > >>>> > >>>> /** > >>>> diff --git a/drivers/thermal/intel/intel_powerclamp.c b/drivers/thermal/intel/intel_powerclamp.c > >>>> index 53216dcbe173..b55786c169ae 100644 > >>>> --- a/drivers/thermal/intel/intel_powerclamp.c > >>>> +++ b/drivers/thermal/intel/intel_powerclamp.c > >>>> @@ -29,6 +29,7 @@ > >>>> #include > >>>> #include > >>>> #include > >>>> +#include > >>>> #include > >>>> #include > >>>> #include > >>>> @@ -430,7 +431,8 @@ static void clamp_idle_injection_func(struct kthread_work *work) > >>>> if (should_skip) > >>>> goto balance; > >>>> > >>>> - play_idle(jiffies_to_usecs(w_data->duration_jiffies)); > >>>> + play_idle(jiffies_to_usecs(w_data->duration_jiffies), > >>>> + cpuidle_find_deepest_state()); > >>> > >>> I don't see a reason for changing the code here like this. > >>> > >>> What you really need is to have a way to set a limit on the idle > >>> state exit latency for idle injection on ARM. > >> > >> Mmh, yes you are right. The idle state number is part of the internals > >> of the cpuidle framework while the exit latency is an input (from user > >> or kernel). > >> > >>> For that you can pass the exit latency limit to play_idle(), but then > >>> you need to change powerclamp to pass UNIT_MAX or similar which is > >>> ugly, or you can redefine cpuidle_use_deepest_state() to take the > >>> exit latency limit as the arg (with 0 meaning use_deepest_state == false). > >> > >> Should it make sense to just get the resume latency in > >> cpuidle_use_deepest_state() and pass the value to find_deepest_state()? > > > > Yes, I would change cpuidle_use_deepest_state() to take the max exit > > latency as the arg (maybe with 0 meaning "don't use the deepest state > > only any more"). > > Why not simply ? > > int cpuidle_find_deepest_state(struct cpuidle_driver *drv, > struct cpuidle_device *dev) > { > int latency = cpuidle_governor_latency_req(dev->cpu); > > return find_deepest_state(drv, dev, latency_req, 0, false); > } Because, AFAICS, that doesn't work for powerclamp.