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=-8.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham 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 740FDC4CEC4 for ; Mon, 23 Sep 2019 18:47:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3830320820 for ; Mon, 23 Sep 2019 18:47:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="IYUeEtJX" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731169AbfIWSry (ORCPT ); Mon, 23 Sep 2019 14:47:54 -0400 Received: from mail-pf1-f194.google.com ([209.85.210.194]:44569 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726993AbfIWSry (ORCPT ); Mon, 23 Sep 2019 14:47:54 -0400 Received: by mail-pf1-f194.google.com with SMTP id q21so9632088pfn.11 for ; Mon, 23 Sep 2019 11:47:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=0CBkmXcDAyhOIJqhA2ULW0sHJ2yoexO3BhmE1zV/RMg=; b=IYUeEtJXp7RVmhOXjjhxUXjVjWFTgGkRXaUGQ0di134k5x9Mwm/JDvEu242RNxyoXm fPblK8yjEFZnouwPLm9MDga24tjCFS13RKja4XHC1rVPLb6/9ssRB/25XPo2xidjSEf5 8iowXvgKdkzq8LEW3hFSSNPtdqfeGetOY8cxs= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=0CBkmXcDAyhOIJqhA2ULW0sHJ2yoexO3BhmE1zV/RMg=; b=YjshJS3FZuB9J6Clu6E3UqG9IH3D3lY2PcCbalS44e/RFrZ5rD9Hn0RRWOSDKOGa6F Ej0FX6bt6KV4qQrytYbkZXe3icn21rVz7BRluVS0yrWuvY/et0MpJnaZDq0hR6iABh3C 72JmbBMdKmwaFSQXrFdSKHwekcWz5/lWOlLDWfjS74cKh7mXyaC8MfYhtnIYyhDhZOpe liJaMD9v36uy0RY8gicXm1KQfS3kkgUlL+UI5M790HWiysz4azz/V5JgByZN03hk+LD9 bMo4nDC4mOti+G3Y910ntWWiK9fzHj8NeiQGIvtelIDs8a/Rc3MZ9H0wUjQ0rcTEVDYA gvHw== X-Gm-Message-State: APjAAAVgu3eja3lJaDC/Sf8QXyBBoB+0G8o2sNzmyQtCExy57cjGrhf+ ERX4L+IUwiTqUbSys7KX94tEtw== X-Google-Smtp-Source: APXvYqwY4PIF+uaXM+GJQN/H4ktQnNEgQ3czxz00rTi2CUVRwIag2ol+YEKs+3UJsBpl44llMWgg9w== X-Received: by 2002:a62:32c5:: with SMTP id y188mr1072011pfy.97.1569264473646; Mon, 23 Sep 2019 11:47:53 -0700 (PDT) Received: from localhost ([2620:15c:202:1:75a:3f6e:21d:9374]) by smtp.gmail.com with ESMTPSA id t68sm11213382pgt.61.2019.09.23.11.47.52 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 23 Sep 2019 11:47:53 -0700 (PDT) Date: Mon, 23 Sep 2019 11:47:50 -0700 From: Matthias Kaehlcke To: Leonard Crestez Cc: MyungJoo Ham , Kyungmin Park , Chanwoo Choi , Artur =?utf-8?B?xZp3aWdvxYQ=?= , Saravana Kannan , Krzysztof Kozlowski , Alexandre Bailon , Georgi Djakov , Abel Vesa , Jacky Bai , Viresh Kumar , Lukasz Luba , linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, NXP Linux Team Subject: Re: [PATCH v6 6/6] PM / devfreq: Use PM QoS for sysfs min/max_freq Message-ID: <20190923184750.GB133864@google.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On Mon, Sep 23, 2019 at 06:51:09PM +0300, Leonard Crestez wrote: > Switch the handling of min_freq and max_freq from sysfs to use the > dev_pm_qos_request interface. > > Since PM QoS handles frequencies as kHz this change reduces the > precision of min_freq and max_freq. This shouldn't introduce problems > because frequencies which are not an integer number of kHz are likely > not an integer number of Hz either. > > Try to ensure compatibility by rounding min values down and rounding > max values up. > > Signed-off-by: Leonard Crestez > --- > drivers/devfreq/devfreq.c | 49 +++++++++++++++++++++++++-------------- > include/linux/devfreq.h | 9 +++---- > 2 files changed, 36 insertions(+), 22 deletions(-) > > diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c > index a4c7dde17a06..4c58fbf7d4e4 100644 > --- a/drivers/devfreq/devfreq.c > +++ b/drivers/devfreq/devfreq.c > @@ -132,14 +132,10 @@ static void devfreq_get_freq_range(struct devfreq *devfreq, > *min_freq = max(*min_freq, HZ_PER_KHZ * (unsigned long)dev_pm_qos_read_value( > devfreq->dev.parent, DEV_PM_QOS_MIN_FREQUENCY)); > *max_freq = min(*max_freq, HZ_PER_KHZ * (unsigned long)dev_pm_qos_read_value( > devfreq->dev.parent, DEV_PM_QOS_MAX_FREQUENCY)); > > - /* constraints from sysfs: */ > - *min_freq = max(*min_freq, devfreq->min_freq); > - *max_freq = min(*max_freq, devfreq->max_freq); > - > /* constraints from OPP interface: */ > *min_freq = max(*min_freq, devfreq->scaling_min_freq); > /* scaling_max_freq can be zero on error */ > if (devfreq->scaling_max_freq) > *max_freq = min(*max_freq, devfreq->scaling_max_freq); > @@ -674,10 +670,12 @@ static void devfreq_dev_release(struct device *dev) > DEV_PM_QOS_MIN_FREQUENCY); > > if (devfreq->profile->exit) > devfreq->profile->exit(devfreq->dev.parent); > > + dev_pm_qos_remove_request(&devfreq->user_max_freq_req); > + dev_pm_qos_remove_request(&devfreq->user_min_freq_req); > kfree(devfreq->time_in_state); > kfree(devfreq->trans_table); > mutex_destroy(&devfreq->lock); > kfree(devfreq); > } > @@ -742,18 +740,26 @@ struct devfreq *devfreq_add_device(struct device *dev, > devfreq->scaling_min_freq = find_available_min_freq(devfreq); > if (!devfreq->scaling_min_freq) { > err = -EINVAL; > goto err_dev; > } > - devfreq->min_freq = devfreq->scaling_min_freq; > > devfreq->scaling_max_freq = find_available_max_freq(devfreq); > if (!devfreq->scaling_max_freq) { > err = -EINVAL; > goto err_dev; > } > - devfreq->max_freq = devfreq->scaling_max_freq; > + > + /* PM QoS requests for min/max freq from sysfs */ > + err = dev_pm_qos_add_request(dev, &devfreq->user_min_freq_req, > + DEV_PM_QOS_MIN_FREQUENCY, 0); > + if (err < 0) > + goto err_dev; > + err = dev_pm_qos_add_request(dev, &devfreq->user_max_freq_req, > + DEV_PM_QOS_MAX_FREQUENCY, S32_MAX); > + if (err < 0) > + goto err_dev; > > devfreq->suspend_freq = dev_pm_opp_get_suspend_opp_freq(dev); > atomic_set(&devfreq->suspend_count, 0); > > devfreq->trans_table = kzalloc( > @@ -837,10 +843,14 @@ struct devfreq *devfreq_add_device(struct device *dev, > err_dev: > /* > * Cleanup path for errors that happen before registration. > * Otherwise we rely on devfreq_dev_release > */ > + if (dev_pm_qos_request_active(&devfreq->user_max_freq_req)) > + dev_pm_qos_remove_request(&devfreq->user_max_freq_req); > + if (dev_pm_qos_request_active(&devfreq->user_min_freq_req)) > + dev_pm_qos_remove_request(&devfreq->user_min_freq_req); > kfree(devfreq->time_in_state); > kfree(devfreq->trans_table); > kfree(devfreq); > err_out: > return ERR_PTR(err); > @@ -1401,14 +1411,17 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr, > > ret = sscanf(buf, "%lu", &value); > if (ret != 1) > return -EINVAL; > > - mutex_lock(&df->lock); > - df->min_freq = value; > - update_devfreq(df); > - mutex_unlock(&df->lock); > + /* round down to kHz for dev_pm_qos */ > + if (value) > + value = value / HZ_PER_KHZ; > + > + ret = dev_pm_qos_update_request(&df->user_min_freq_req, value); > + if (ret < 0) > + return ret; > > return count; > } > > static ssize_t min_freq_show(struct device *dev, struct device_attribute *attr, > @@ -1433,19 +1446,19 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr, > > ret = sscanf(buf, "%lu", &value); > if (ret != 1) > return -EINVAL; > > - mutex_lock(&df->lock); > - > - /* Interpret zero as "don't care" */ > - if (!value) > - value = ULONG_MAX; > + /* round up to kHz for dev_pm_qos and interpret zero as "don't care" */ > + if (value) > + value = DIV_ROUND_UP(value, HZ_PER_KHZ); > + else > + value = S32_MAX; > > - df->max_freq = value; > - update_devfreq(df); > - mutex_unlock(&df->lock); > + ret = dev_pm_qos_update_request(&df->user_max_freq_req, value); > + if (ret < 0) > + return ret; > > return count; > } > static DEVICE_ATTR_RW(min_freq); > > diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h > index dac0dffeabb4..7849fe4c666d 100644 > --- a/include/linux/devfreq.h > +++ b/include/linux/devfreq.h > @@ -11,10 +11,11 @@ > #define __LINUX_DEVFREQ_H__ > > #include > #include > #include > +#include > > #define DEVFREQ_NAME_LEN 16 > > /* DEVFREQ governor name */ > #define DEVFREQ_GOV_SIMPLE_ONDEMAND "simple_ondemand" > @@ -121,12 +122,12 @@ struct devfreq_dev_profile { > * devfreq.nb to the corresponding register notifier call chain. > * @work: delayed work for load monitoring. > * @previous_freq: previously configured frequency value. > * @data: Private data of the governor. The devfreq framework does not > * touch this. > - * @min_freq: Limit minimum frequency requested by user (0: none) > - * @max_freq: Limit maximum frequency requested by user (0: none) > + * @user_min_freq_req: PM QoS min frequency request from user (via sysfs) > + * @user_max_freq_req: PM QoS max frequency request from user (via sysfs) > * @scaling_min_freq: Limit minimum frequency requested by OPP interface > * @scaling_max_freq: Limit maximum frequency requested by OPP interface > * @stop_polling: devfreq polling status of a device. > * @suspend_freq: frequency of a device set during suspend phase. > * @resume_freq: frequency of a device set in resume phase. > @@ -161,12 +162,12 @@ struct devfreq { > unsigned long previous_freq; > struct devfreq_dev_status last_status; > > void *data; /* private data for governors */ > > - unsigned long min_freq; > - unsigned long max_freq; > + struct dev_pm_qos_request user_min_freq_req; > + struct dev_pm_qos_request user_max_freq_req; > unsigned long scaling_min_freq; > unsigned long scaling_max_freq; > bool stop_polling; > > unsigned long suspend_freq; Reviewed-by: Matthias Kaehlcke