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=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 5D748C2D0C5 for ; Tue, 17 Dec 2019 09:10:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3D0E72176D for ; Tue, 17 Dec 2019 09:10:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726783AbfLQJKe (ORCPT ); Tue, 17 Dec 2019 04:10:34 -0500 Received: from foss.arm.com ([217.140.110.172]:58904 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725805AbfLQJKe (ORCPT ); Tue, 17 Dec 2019 04:10:34 -0500 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 B7A4C30E; Tue, 17 Dec 2019 01:10:31 -0800 (PST) Received: from [10.37.12.145] (unknown [10.37.12.145]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 680673F6CF; Tue, 17 Dec 2019 01:10:27 -0800 (PST) Subject: Re: [PATCH 7/7] devfreq: move statistics to separate struct To: Chanwoo Choi Cc: Bartlomiej Zolnierkiewicz , Javi Merino , linux-samsung-soc@vger.kernel.org, linux-pm@vger.kernel.org, Kamil Konieczny , linux-kernel@vger.kernel.org, Krzysztof Kozlowski , Eduardo Valentin , Kyungmin Park , Kukjin Kim , MyungJoo Ham , Zhang Rui , =?UTF-8?Q?=c3=98rjan_Eide?= , linux-arm-kernel@lists.infradead.org, Marek Szyprowski , Dietmar Eggemann , a.hajda@samsung.com, robin.murphy@arm.com References: <20191113091336.5218-1-k.konieczny@samsung.com> <20191113091336.5218-8-k.konieczny@samsung.com> <4942d2ad-fef7-89be-91c1-c02c319546ff@samsung.com> <38350d81-e916-b386-6727-f4c85689c172@samsung.com> <85a29ce4-0f89-2b50-b046-dba747208933@samsung.com> <4ed6b8bf-b415-c42d-33d6-d2ed0504eaf4@samsung.com> <09c52ab9-fb99-62e1-07b3-1e124f0e96f8@samsung.com> From: Lukasz Luba Message-ID: <893a0d64-0bff-dea1-6e6a-78e5d59d2a13@arm.com> Date: Tue, 17 Dec 2019 09:10:24 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <09c52ab9-fb99-62e1-07b3-1e124f0e96f8@samsung.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Chanwoo, On 12/17/19 12:07 AM, Chanwoo Choi wrote: > Hi Lukaz, > > On 12/16/19 10:01 PM, Lukasz Luba wrote: >> Hi Bartek, >> >> [added Dietmar, Robin, Andrzej (for upcoming DRM drm-misc-next)] >> >> On 11/15/19 12:40 PM, Bartlomiej Zolnierkiewicz wrote: >>> >>> [ added Zhang, Eduardo, Ørjan and Javi to Cc: ] >>> >>> On 11/15/19 7:21 AM, Chanwoo Choi wrote: >>>> Hi Bartlomiej, >>>> >>>> On 11/15/19 12:25 PM, Chanwoo Choi wrote: >>>>> Hi Bartlomiej, >>>>> >>>>> On 11/15/19 3:01 AM, Bartlomiej Zolnierkiewicz wrote: >>>>>> >>>>>> Hi Chanwoo, >>>>>> >>>>>> On 11/14/19 2:52 AM, Chanwoo Choi wrote: >>>>>>> Hi Kamil, >>>>>>> >>>>>>> The 'freq_table' and 'max_state' in the devfreq_dev_profile >>>>>>> were used in the ARM Mali device driver[1][2][3]. Although ARM Mali >>>>>>> device driver was posted to mainline kernel, they used >>>>>>> them for a long time. It means that this patch break >>>>>>> the compatibility. The ARM Mali drivers are very >>>>>>> important devfreq device driver. >>>>>> >>>>>> This argument is not a a technical one and the official upstream >>>>>> kernel policy is to not depend on out-of-tree drivers. >>>>>> >>>>>> Besides the ARM Mali drivers are full of code like: >>>>>> >>>>>> #if LINUX_VERSION_CODE >= KERNEL_VERSION(x, y, z) >>>>>> ... >>>>>> #else >>>>>> ... >>>>>> #endif >>>>>> >>>>>> so few more instances of similar code won't do any harm.. ;-) >>>>>> >>>>>>> [1] https://protect2.fireeye.com/url?k=909caa5c-cd52abe8-909d2113-000babdfecba-812f16576c3614a3&u=https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/bifrost-kernel# >>>>>>> [2] https://protect2.fireeye.com/url?k=33265f96-6ee85e22-3327d4d9-000babdfecba-44c2daec328712e6&u=https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/midgard-kernel >>>>>>> [3] https://protect2.fireeye.com/url?k=69bdcab0-3473cb04-69bc41ff-000babdfecba-4b576facf85e0208&u=https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/utgard-kernel >>>>>> >>>>>> I took a look at ARM Mali drivers source code anyway and I fail to >>>>>> see a rationale behind their behavior of doing 'freq_table' and >>>>>> 'max_state' initialization in the driver itself (instead of leaving >>>>>> it up to the devfreq core code, like all in-kernel drivers are doing >>>>>> already). >>>>>> >>>>>> Could you please explain rationale behind ARM Mali drivers' special >>>>>> needs? >>>>>> >>>>>> [ Both ARM Mali and devfreq core code are using generic PM OPP code >>>>>>    these days to do 'freq_table' and 'max_state' initialization, the >>>>>>    only difference seems to be that ARM Mali creates the frequency >>>>>>    table in the descending order (but there also seems to be no real >>>>>>    need for it). ] >>>>>> >>>>>> Maybe this is an opportunity to simplify also the ARM Mali driver? >>>>> >>>>> OK. I agree to simplify them on this time. >>>>> For touching the 'freq_table' and 'max_state', need to fix >>>>> the descending order of freq_table. >>>>> >>>>> The partition_enable_ops() in the drivers/thermal/devfreq_cooling.c >>>>> requires the descending order of freq_table. Have to change it by using >>>>> the ascending time or support both ascending and descending order for freq_table. >>>>> >>>>> 1. Move freq_table, max_state of devfreq_dev_profile to struct devfreq >>>>> 2. Edit partition_enable_ops() in the drivers/thermal/devfreq_cooling.c >>>>>     by using ascending order instead of descending order. >>>>> >>>> >>>> After changed about 'freq_table' and 'max_state', the build error >>>> will happen on ARM mail driver because the initialization code of >>>> 'freq_table' in ARM mali driver, didn't check the kernel version. >>>> >>>> The first devfreq patch provided the 'freq_table' as optional variable >>>> in the 'struct devfreq_dev_profile'. Even if ARM mali driver is out of mainline tree, >>>> this change seems that break the usage rule of 'freq_table' in 'struct devfreq_dev_profile'. >>>> >>>> So, if there are no any beneficial reason, I just keep the current status of 'freq_table' >>>> in order to keep the previous usage rule of 'freq_table' in 'struct devfreq_dev_profile'. >>>> >>>> Frankly, I'm note sure that it is necessary. I don't want to make >>>> the side-effect without any useful reason. >>>> >>>> But, >>>> Separately, have to fix the ordering issue of partition_enable_ops() >>>> in the drivers/thermal/devfreq_cooling.c. >>> >>> Hmmm.. fixing partition_enable_opps() should be trivial but I wonder >>> why we are carrying devfreq_cooling.c code in upstream kernel at all? >> >> Well, the devfreq_cooling.c is going to have a client in mainline: >> the GPU driver - Panfrost. >> >> It is already in DRM branch 'drm-misc-next': >> https://protect2.fireeye.com/url?k=75a0e087-283b1ce4-75a16bc8-0cc47a31cdbc-4953aa9e0574f6dc&u=https://patchwork.freedesktop.org/patch/342848/ >> >> Regarding the devfreq_cooling.c code structure. >> I am currently working on cleaning up the devfreq cooling code and >> adding Energy Model instead for private freq, power tables. It will be >> in similar fashion as it is done in cpufreq_cooling. The model will >> be also simplified so hopefully more clients would come. >> It is under internal review and will be posted shortly. > > Good news about Energy Model. When you send the patch related to Energy model, > please add me to Cc list. I will add you, thanks. More eyeballs in capturing bugs are more than welcome. Regards, Lukasz > >> >>> >>> It has been merged in the following commit: >>> >>> commit a76caf55e5b356ba20a5a43ac4d9f7a04b20941d >>> Author: Ørjan Eide >>> Date:   Thu Sep 10 18:09:30 2015 +0100 >>> >>>      thermal: Add devfreq cooling >>>           Add a generic thermal cooling device for devfreq, that is similar to >>>      cpu_cooling. >>>           The device must use devfreq.  In order to use the power extension of the >>>      cooling device, it must have registered its OPPs using the OPP library. >>>           Cc: Zhang Rui >>>      Cc: Eduardo Valentin >>>      Signed-off-by: Javi Merino >>>      Signed-off-by: Ørjan Eide >>>      Signed-off-by: Eduardo Valentin >>> ... >>> >>> but 4 years later there is still no single in-kernel user for this code? >> >> There will be, via DRM tree. >> >> Regards, >> Lukasz >> >>> >>> Best regards, >>> -- >>> Bartlomiej Zolnierkiewicz >>> Samsung R&D Institute Poland >>> Samsung Electronics >>> >>>>>> >>>>>>> Also, the devfreq device driver specifies their own >>>>>>> information and data into devfreq_dev_profile structure >>>>>>> before registering the devfreq device with devfreq_add_device(). >>>>>>> This patch breaks the basic usage rule of devfreq_dev_profile structure. >>>>>> >>>>>> Well, 'struct devfreq_stats *stats' can be trivially moved out of >>>>>> 'struct devfreq_profile' to 'struct devfreq' if you prefer it that >>>>>> way.. >>>>>> >>>>>> Best regards, >>>>>> -- >>>>>> Bartlomiej Zolnierkiewicz >>>>>> Samsung R&D Institute Poland >>>>>> Samsung Electronics >>>>>> >>>>>>> So, I can't agree this patch. Not ack. >>>>>>> >>>>>>> Regards, >>>>>>> Chanwoo Choi >>>>>>> >>>>>>> On 11/13/19 6:13 PM, Kamil Konieczny wrote: >>>>>>>> Count time and transitions between devfreq frequencies in separate struct >>>>>>>> for improved code readability and maintenance. >>>>>>>> >>>>>>>> Signed-off-by: Kamil Konieczny >>>>>>>> --- >>>>>>>>   drivers/devfreq/devfreq.c          | 156 ++++++++++++++++------------- >>>>>>>>   drivers/devfreq/exynos-bus.c       |   6 +- >>>>>>>>   drivers/devfreq/governor_passive.c |  26 +++-- >>>>>>>>   include/linux/devfreq.h            |  43 ++++---- >>>>>>>>   4 files changed, 129 insertions(+), 102 deletions(-) >>>>>>>> >>>>>>>> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c >>>>>>>> index d79412b0de59..d85867a91230 100644 >>>>>>>> --- a/drivers/devfreq/devfreq.c >>>>>>>> +++ b/drivers/devfreq/devfreq.c >>>>>>>> @@ -105,10 +105,11 @@ static unsigned long find_available_max_freq(struct devfreq *devfreq) >>>>>>>>    */ >>>>>>>>   static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq) >>>>>>>>   { >>>>>>>> +    struct devfreq_stats *stats = devfreq->profile->stats; >>>>>>>>       int lev; >>>>>>>>   -    for (lev = 0; lev < devfreq->profile->max_state; lev++) >>>>>>>> -        if (freq == devfreq->profile->freq_table[lev]) >>>>>>>> +    for (lev = 0; lev < stats->max_state; lev++) >>>>>>>> +        if (freq == stats->freq_table[lev]) >>>>>>>>               return lev; >>>>>>>>         return -EINVAL; >>>>>>>> @@ -117,56 +118,64 @@ static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq) >>>>>>>>   static int set_freq_table(struct devfreq *devfreq) >>>>>>>>   { >>>>>>>>       struct devfreq_dev_profile *profile = devfreq->profile; >>>>>>>> +    struct devfreq_stats *stats; >>>>>>>>       struct dev_pm_opp *opp; >>>>>>>>       unsigned long freq; >>>>>>>> -    int i, count; >>>>>>>> +    int i, count, err = -ENOMEM; >>>>>>>>         /* Initialize the freq_table from OPP table */ >>>>>>>>       count = dev_pm_opp_get_opp_count(devfreq->dev.parent); >>>>>>>>       if (count <= 0) >>>>>>>>           return -EINVAL; >>>>>>>>   -    profile->max_state = count; >>>>>>>> -    profile->freq_table = devm_kcalloc(devfreq->dev.parent, >>>>>>>> -                    count, >>>>>>>> -                    sizeof(*profile->freq_table), >>>>>>>> -                    GFP_KERNEL); >>>>>>>> -    if (!profile->freq_table) { >>>>>>>> -        profile->max_state = 0; >>>>>>>> +    stats = devm_kzalloc(devfreq->dev.parent, >>>>>>>> +                 sizeof(struct devfreq_stats), GFP_KERNEL); >>>>>>>> +    if (!stats) >>>>>>>>           return -ENOMEM; >>>>>>>> -    } >>>>>>>>   -    for (i = 0, freq = 0; i < profile->max_state; i++, freq++) { >>>>>>>> +    profile->stats = stats; >>>>>>>> +    stats->max_state = count; >>>>>>>> +    stats->freq_table = devm_kcalloc(devfreq->dev.parent, >>>>>>>> +                     count, >>>>>>>> +                     sizeof(*stats->freq_table), >>>>>>>> +                     GFP_KERNEL); >>>>>>>> +    if (!stats->freq_table) >>>>>>>> +        goto err_no_mem; >>>>>>>> + >>>>>>>> +    for (i = 0, freq = 0; i < count; i++, freq++) { >>>>>>>>           opp = dev_pm_opp_find_freq_ceil(devfreq->dev.parent, &freq); >>>>>>>>           if (IS_ERR(opp)) { >>>>>>>> -            devm_kfree(devfreq->dev.parent, profile->freq_table); >>>>>>>> -            profile->max_state = 0; >>>>>>>> -            return PTR_ERR(opp); >>>>>>>> +            devm_kfree(devfreq->dev.parent, stats->freq_table); >>>>>>>> +            stats->max_state = 0; >>>>>>>> +            err = PTR_ERR(opp); >>>>>>>> +            goto err_no_mem; >>>>>>>>           } >>>>>>>>           dev_pm_opp_put(opp); >>>>>>>> -        profile->freq_table[i] = freq; >>>>>>>> +        stats->freq_table[i] = freq; >>>>>>>>       } >>>>>>>>   -    profile->trans_table = devm_kzalloc(devfreq->dev.parent, >>>>>>>> -                        array3_size(sizeof(unsigned int), >>>>>>>> -                            count, count), >>>>>>>> -                        GFP_KERNEL); >>>>>>>> -    if (!profile->trans_table) >>>>>>>> +    stats->trans_table = devm_kzalloc(devfreq->dev.parent, >>>>>>>> +                      array3_size(sizeof(unsigned int), >>>>>>>> +                              count, count), >>>>>>>> +                      GFP_KERNEL); >>>>>>>> +    if (!stats->trans_table) >>>>>>>>           goto err_no_mem; >>>>>>>>   -    profile->time_in_state = devm_kcalloc(devfreq->dev.parent, count, >>>>>>>> -                          sizeof(*profile->time_in_state), >>>>>>>> -                          GFP_KERNEL); >>>>>>>> -    if (!profile->time_in_state) >>>>>>>> +    stats->time_in_state = devm_kcalloc(devfreq->dev.parent, count, >>>>>>>> +                        sizeof(*stats->time_in_state), >>>>>>>> +                        GFP_KERNEL); >>>>>>>> +    if (!stats->time_in_state) >>>>>>>>           goto err_no_mem; >>>>>>>>   -    profile->last_time = get_jiffies_64(); >>>>>>>> -    spin_lock_init(&profile->stats_lock); >>>>>>>> +    stats->last_time = get_jiffies_64(); >>>>>>>> +    spin_lock_init(&stats->stats_lock); >>>>>>>>         return 0; >>>>>>>>   err_no_mem: >>>>>>>> -    profile->max_state = 0; >>>>>>>> -    return -ENOMEM; >>>>>>>> +    stats->max_state = 0; >>>>>>>> +    devm_kfree(devfreq->dev.parent, profile->stats); >>>>>>>> +    profile->stats = NULL; >>>>>>>> +    return err; >>>>>>>>   } >>>>>>>>     /** >>>>>>>> @@ -176,7 +185,7 @@ static int set_freq_table(struct devfreq *devfreq) >>>>>>>>    */ >>>>>>>>   int devfreq_update_status(struct devfreq *devfreq, unsigned long freq) >>>>>>>>   { >>>>>>>> -    struct devfreq_dev_profile *profile = devfreq->profile; >>>>>>>> +    struct devfreq_stats *stats = devfreq->profile->stats; >>>>>>>>       unsigned long long cur_time; >>>>>>>>       int lev, prev_lev, ret = 0; >>>>>>>>   @@ -184,22 +193,21 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq) >>>>>>>>         /* Immediately exit if previous_freq is not initialized yet. */ >>>>>>>>       if (!devfreq->previous_freq) { >>>>>>>> -        spin_lock(&profile->stats_lock); >>>>>>>> -        profile->last_time = cur_time; >>>>>>>> -        spin_unlock(&profile->stats_lock); >>>>>>>> +        spin_lock(&stats->stats_lock); >>>>>>>> +        stats->last_time = cur_time; >>>>>>>> +        spin_unlock(&stats->stats_lock); >>>>>>>>           return 0; >>>>>>>>       } >>>>>>>>         prev_lev = devfreq_get_freq_level(devfreq, devfreq->previous_freq); >>>>>>>>   -    spin_lock(&profile->stats_lock); >>>>>>>> +    spin_lock(&stats->stats_lock); >>>>>>>>       if (prev_lev < 0) { >>>>>>>>           ret = prev_lev; >>>>>>>>           goto out; >>>>>>>>       } >>>>>>>>   -    profile->time_in_state[prev_lev] += >>>>>>>> -             cur_time - profile->last_time; >>>>>>>> +    stats->time_in_state[prev_lev] += cur_time - stats->last_time; >>>>>>>>       lev = devfreq_get_freq_level(devfreq, freq); >>>>>>>>       if (lev < 0) { >>>>>>>>           ret = lev; >>>>>>>> @@ -207,14 +215,14 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq) >>>>>>>>       } >>>>>>>>         if (lev != prev_lev) { >>>>>>>> -        profile->trans_table[(prev_lev * >>>>>>>> -                profile->max_state) + lev]++; >>>>>>>> -        profile->total_trans++; >>>>>>>> +        stats->trans_table[(prev_lev * >>>>>>>> +                stats->max_state) + lev]++; >>>>>>>> +        stats->total_trans++; >>>>>>>>       } >>>>>>>>     out: >>>>>>>> -    profile->last_time = cur_time; >>>>>>>> -    spin_unlock(&profile->stats_lock); >>>>>>>> +    stats->last_time = cur_time; >>>>>>>> +    spin_unlock(&stats->stats_lock); >>>>>>>>       return ret; >>>>>>>>   } >>>>>>>>   EXPORT_SYMBOL(devfreq_update_status); >>>>>>>> @@ -504,9 +512,9 @@ void devfreq_monitor_resume(struct devfreq *devfreq) >>>>>>>>           queue_delayed_work(devfreq_wq, &devfreq->work, >>>>>>>>               msecs_to_jiffies(profile->polling_ms)); >>>>>>>>   -    spin_lock(&profile->stats_lock); >>>>>>>> -    profile->last_time = get_jiffies_64(); >>>>>>>> -    spin_unlock(&profile->stats_lock); >>>>>>>> +    spin_lock(&profile->stats->stats_lock); >>>>>>>> +    profile->stats->last_time = get_jiffies_64(); >>>>>>>> +    spin_unlock(&profile->stats->stats_lock); >>>>>>>>       devfreq->stop_polling = false; >>>>>>>>         if (profile->get_cur_freq && >>>>>>>> @@ -677,7 +685,7 @@ struct devfreq *devfreq_add_device(struct device *dev, >>>>>>>>       devfreq->data = data; >>>>>>>>       devfreq->nb.notifier_call = devfreq_notifier_call; >>>>>>>>   -    if (!profile->max_state && !profile->freq_table) { >>>>>>>> +    if (!profile->stats) { >>>>>>>>           mutex_unlock(&devfreq->lock); >>>>>>>>           err = set_freq_table(devfreq); >>>>>>>>           if (err < 0) >>>>>>>> @@ -1282,6 +1290,7 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr, >>>>>>>>                     const char *buf, size_t count) >>>>>>>>   { >>>>>>>>       struct devfreq *df = to_devfreq(dev); >>>>>>>> +    struct devfreq_stats *stats = df->profile->stats; >>>>>>>>       unsigned long value; >>>>>>>>       int ret; >>>>>>>>   @@ -1297,13 +1306,13 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr, >>>>>>>>               goto unlock; >>>>>>>>           } >>>>>>>>       } else { >>>>>>>> -        unsigned long *freq_table = df->profile->freq_table; >>>>>>>> +        unsigned long *freq_table = stats->freq_table; >>>>>>>>             /* Get minimum frequency according to sorting order */ >>>>>>>> -        if (freq_table[0] < freq_table[df->profile->max_state - 1]) >>>>>>>> +        if (freq_table[0] < freq_table[stats->max_state - 1]) >>>>>>>>               value = freq_table[0]; >>>>>>>>           else >>>>>>>> -            value = freq_table[df->profile->max_state - 1]; >>>>>>>> +            value = freq_table[stats->max_state - 1]; >>>>>>>>       } >>>>>>>>         df->min_freq = value; >>>>>>>> @@ -1326,6 +1335,7 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr, >>>>>>>>                     const char *buf, size_t count) >>>>>>>>   { >>>>>>>>       struct devfreq *df = to_devfreq(dev); >>>>>>>> +    struct devfreq_stats *stats = df->profile->stats; >>>>>>>>       unsigned long value; >>>>>>>>       int ret; >>>>>>>>   @@ -1341,11 +1351,11 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr, >>>>>>>>               goto unlock; >>>>>>>>           } >>>>>>>>       } else { >>>>>>>> -        unsigned long *freq_table = df->profile->freq_table; >>>>>>>> +        unsigned long *freq_table = stats->freq_table; >>>>>>>>             /* Get maximum frequency according to sorting order */ >>>>>>>> -        if (freq_table[0] < freq_table[df->profile->max_state - 1]) >>>>>>>> -            value = freq_table[df->profile->max_state - 1]; >>>>>>>> +        if (freq_table[0] < freq_table[stats->max_state - 1]) >>>>>>>> +            value = freq_table[stats->max_state - 1]; >>>>>>>>           else >>>>>>>>               value = freq_table[0]; >>>>>>>>       } >>>>>>>> @@ -1373,14 +1383,15 @@ static ssize_t available_frequencies_show(struct device *d, >>>>>>>>                         char *buf) >>>>>>>>   { >>>>>>>>       struct devfreq *df = to_devfreq(d); >>>>>>>> +    struct devfreq_stats *stats = df->profile->stats; >>>>>>>>       ssize_t count = 0; >>>>>>>>       int i; >>>>>>>>         mutex_lock(&df->lock); >>>>>>>>   -    for (i = 0; i < df->profile->max_state; i++) >>>>>>>> +    for (i = 0; i < stats->max_state; i++) >>>>>>>>           count += scnprintf(&buf[count], (PAGE_SIZE - count - 2), >>>>>>>> -                "%lu ", df->profile->freq_table[i]); >>>>>>>> +                "%lu ", stats->freq_table[i]); >>>>>>>>         mutex_unlock(&df->lock); >>>>>>>>       /* Truncate the trailing space */ >>>>>>>> @@ -1398,9 +1409,10 @@ static ssize_t trans_stat_show(struct device *dev, >>>>>>>>   { >>>>>>>>       struct devfreq *devfreq = to_devfreq(dev); >>>>>>>>       struct devfreq_dev_profile *profile = devfreq->profile; >>>>>>>> +    struct devfreq_stats *stats = profile->stats; >>>>>>>> +    unsigned int max_state = stats->max_state; >>>>>>>>       ssize_t len; >>>>>>>>       int i, j; >>>>>>>> -    unsigned int max_state = profile->max_state; >>>>>>>>         if (!devfreq->stop_polling && >>>>>>>>               devfreq_update_status(devfreq, devfreq->previous_freq)) >>>>>>>> @@ -1411,45 +1423,45 @@ static ssize_t trans_stat_show(struct device *dev, >>>>>>>>       len = sprintf(buf, "     From  :   To\n"); >>>>>>>>       len += sprintf(buf + len, "           :"); >>>>>>>>   -    spin_lock(&profile->stats_lock); >>>>>>>> +    spin_lock(&stats->stats_lock); >>>>>>>>       for (i = 0; i < max_state; i++) >>>>>>>>           len += sprintf(buf + len, "%10lu", >>>>>>>> -                profile->freq_table[i]); >>>>>>>> +                stats->freq_table[i]); >>>>>>>>         len += sprintf(buf + len, "   time(ms)\n"); >>>>>>>>         for (i = 0; i < max_state; i++) { >>>>>>>> -        if (profile->freq_table[i] == devfreq->previous_freq) >>>>>>>> +        if (stats->freq_table[i] == devfreq->previous_freq) >>>>>>>>               len += sprintf(buf + len, "*"); >>>>>>>>           else >>>>>>>>               len += sprintf(buf + len, " "); >>>>>>>>             len += sprintf(buf + len, "%10lu:", >>>>>>>> -                profile->freq_table[i]); >>>>>>>> +                stats->freq_table[i]); >>>>>>>>           for (j = 0; j < max_state; j++) >>>>>>>>               len += sprintf(buf + len, "%10u", >>>>>>>> -                profile->trans_table[(i * max_state) + j]); >>>>>>>> +                stats->trans_table[(i * max_state) + j]); >>>>>>>>           len += sprintf(buf + len, "%10llu\n", (u64) >>>>>>>> -            jiffies64_to_msecs(profile->time_in_state[i])); >>>>>>>> +            jiffies64_to_msecs(stats->time_in_state[i])); >>>>>>>>       } >>>>>>>>         len += sprintf(buf + len, "Total transition : %u\n", >>>>>>>> -                    profile->total_trans); >>>>>>>> -    spin_unlock(&profile->stats_lock); >>>>>>>> +                    stats->total_trans); >>>>>>>> +    spin_unlock(&stats->stats_lock); >>>>>>>>       return len; >>>>>>>>   } >>>>>>>>   static DEVICE_ATTR_RO(trans_stat); >>>>>>>>   -static void defvreq_stats_clear_table(struct devfreq_dev_profile *profile) >>>>>>>> +static void defvreq_stats_clear_table(struct devfreq_stats *stats) >>>>>>>>   { >>>>>>>> -    unsigned int count = profile->max_state; >>>>>>>> - >>>>>>>> -    spin_lock(&profile->stats_lock); >>>>>>>> -    memset(profile->time_in_state, 0, count * sizeof(u64)); >>>>>>>> -    memset(profile->trans_table, 0, count * count * sizeof(int)); >>>>>>>> -    profile->last_time = get_jiffies_64(); >>>>>>>> -    profile->total_trans = 0; >>>>>>>> -    spin_unlock(&profile->stats_lock); >>>>>>>> +    unsigned int count = stats->max_state; >>>>>>>> + >>>>>>>> +    spin_lock(&stats->stats_lock); >>>>>>>> +    memset(stats->time_in_state, 0, count * sizeof(u64)); >>>>>>>> +    memset(stats->trans_table, 0, count * count * sizeof(int)); >>>>>>>> +    stats->last_time = get_jiffies_64(); >>>>>>>> +    stats->total_trans = 0; >>>>>>>> +    spin_unlock(&stats->stats_lock); >>>>>>>>   } >>>>>>>>     static ssize_t trans_reset_store(struct device *dev, >>>>>>>> @@ -1459,7 +1471,7 @@ static ssize_t trans_reset_store(struct device *dev, >>>>>>>>   { >>>>>>>>       struct devfreq *devfreq = to_devfreq(dev); >>>>>>>>   -    defvreq_stats_clear_table(devfreq->profile); >>>>>>>> +    defvreq_stats_clear_table(devfreq->profile->stats); >>>>>>>>         return count; >>>>>>>>   } >>>>>>>> diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c >>>>>>>> index d9f377912c10..b212aae2bb3e 100644 >>>>>>>> --- a/drivers/devfreq/exynos-bus.c >>>>>>>> +++ b/drivers/devfreq/exynos-bus.c >>>>>>>> @@ -496,9 +496,9 @@ static int exynos_bus_probe(struct platform_device *pdev) >>>>>>>>       } >>>>>>>>     out: >>>>>>>> -    max_state = bus->devfreq->profile->max_state; >>>>>>>> -    min_freq = (bus->devfreq->profile->freq_table[0] / 1000); >>>>>>>> -    max_freq = (bus->devfreq->profile->freq_table[max_state - 1] / 1000); >>>>>>>> +    max_state = profile->stats->max_state; >>>>>>>> +    min_freq = (profile->stats->freq_table[0] / 1000); >>>>>>>> +    max_freq = (profile->stats->freq_table[max_state - 1] / 1000); >>>>>>>>       pr_info("exynos-bus: new bus device registered: %s (%6ld KHz ~ %6ld KHz)\n", >>>>>>>>               dev_name(dev), min_freq, max_freq); >>>>>>>>   diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c >>>>>>>> index 58308948b863..b2d87a88335c 100644 >>>>>>>> --- a/drivers/devfreq/governor_passive.c >>>>>>>> +++ b/drivers/devfreq/governor_passive.c >>>>>>>> @@ -18,6 +18,8 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq, >>>>>>>>       struct devfreq_passive_data *p_data >>>>>>>>               = (struct devfreq_passive_data *)devfreq->data; >>>>>>>>       struct devfreq *parent_devfreq = (struct devfreq *)p_data->parent; >>>>>>>> +    struct devfreq_stats *parent_stats = parent_devfreq->profile->stats; >>>>>>>> +    struct devfreq_stats *stats; >>>>>>>>       unsigned long child_freq = ULONG_MAX; >>>>>>>>       struct dev_pm_opp *opp; >>>>>>>>       int i, count, ret = 0; >>>>>>>> @@ -47,10 +49,14 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq, >>>>>>>>        * device. And then the index is used for getting the suitable >>>>>>>>        * new frequency for passive devfreq device. >>>>>>>>        */ >>>>>>>> -    if (!devfreq->profile || !devfreq->profile->freq_table >>>>>>>> -        || devfreq->profile->max_state <= 0) >>>>>>>> +    if (!devfreq->profile || !devfreq->profile->stats || >>>>>>>> +        devfreq->profile->stats->max_state <= 0 || >>>>>>>> +        !parent_devfreq->profile ||    !parent_devfreq->profile->stats || >>>>>>>> +        parent_devfreq->profile->stats->max_state <= 0) >>>>>>>>           return -EINVAL; >>>>>>>>   +    stats = devfreq->profile->stats; >>>>>>>> +    parent_stats = parent_devfreq->profile->stats; >>>>>>>>       /* >>>>>>>>        * The passive governor have to get the correct frequency from OPP >>>>>>>>        * list of parent device. Because in this case, *freq is temporary >>>>>>>> @@ -68,21 +74,21 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq, >>>>>>>>        * Get the OPP table's index of decided freqeuncy by governor >>>>>>>>        * of parent device. >>>>>>>>        */ >>>>>>>> -    for (i = 0; i < parent_devfreq->profile->max_state; i++) >>>>>>>> -        if (parent_devfreq->profile->freq_table[i] == *freq) >>>>>>>> +    for (i = 0; i < parent_stats->max_state; i++) >>>>>>>> +        if (parent_stats->freq_table[i] == *freq) >>>>>>>>               break; >>>>>>>>   -    if (i == parent_devfreq->profile->max_state) { >>>>>>>> +    if (i == parent_stats->max_state) { >>>>>>>>           ret = -EINVAL; >>>>>>>>           goto out; >>>>>>>>       } >>>>>>>>         /* Get the suitable frequency by using index of parent device. */ >>>>>>>> -    if (i < devfreq->profile->max_state) { >>>>>>>> -        child_freq = devfreq->profile->freq_table[i]; >>>>>>>> +    if (i < stats->max_state) { >>>>>>>> +        child_freq = stats->freq_table[i]; >>>>>>>>       } else { >>>>>>>> -        count = devfreq->profile->max_state; >>>>>>>> -        child_freq = devfreq->profile->freq_table[count - 1]; >>>>>>>> +        count = stats->max_state; >>>>>>>> +        child_freq = stats->freq_table[count - 1]; >>>>>>>>       } >>>>>>>>         /* Return the suitable frequency for passive device. */ >>>>>>>> @@ -109,7 +115,7 @@ static int update_devfreq_passive(struct devfreq *devfreq, unsigned long freq) >>>>>>>>       if (ret < 0) >>>>>>>>           goto out; >>>>>>>>   -    if (devfreq->profile->freq_table >>>>>>>> +    if (devfreq->profile->stats >>>>>>>>           && (devfreq_update_status(devfreq, freq))) >>>>>>>>           dev_err(&devfreq->dev, >>>>>>>>               "Couldn't update frequency transition information.\n"); >>>>>>>> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h >>>>>>>> index 4ceb2a517a9c..8459af1a1583 100644 >>>>>>>> --- a/include/linux/devfreq.h >>>>>>>> +++ b/include/linux/devfreq.h >>>>>>>> @@ -64,6 +64,30 @@ struct devfreq_dev_status { >>>>>>>>    */ >>>>>>>>   #define DEVFREQ_FLAG_LEAST_UPPER_BOUND        0x1 >>>>>>>>   +/** >>>>>>>> + * struct devfreq_stats - Devfreq's transitions stats counters >>>>>>>> + * @freq_table:        Optional list of frequencies to support statistics >>>>>>>> + *            and freq_table must be generated in ascending order. >>>>>>>> + * @max_state:        The size of freq_table. >>>>>>>> + * @total_trans:    Number of devfreq transitions >>>>>>>> + * @trans_table:    Statistics of devfreq transitions >>>>>>>> + * @time_in_state:    Statistics of devfreq states >>>>>>>> + * @last_time:        The last time stats were updated >>>>>>>> + * @stats_lock:        Lock protecting trans_table, time_in_state, >>>>>>>> + *            last_time and total_trans used for statistics >>>>>>>> + */ >>>>>>>> +struct devfreq_stats { >>>>>>>> +    unsigned long *freq_table; >>>>>>>> +    unsigned int max_state; >>>>>>>> + >>>>>>>> +    /* information for device frequency transition */ >>>>>>>> +    unsigned int total_trans; >>>>>>>> +    unsigned int *trans_table; >>>>>>>> +    u64 *time_in_state; >>>>>>>> +    unsigned long long last_time; >>>>>>>> +    spinlock_t stats_lock; >>>>>>>> +}; >>>>>>>> + >>>>>>>>   /** >>>>>>>>    * struct devfreq_dev_profile - Devfreq's user device profile >>>>>>>>    * @initial_freq:    The operating frequency when devfreq_add_device() is >>>>>>>> @@ -88,15 +112,7 @@ struct devfreq_dev_status { >>>>>>>>    *            from devfreq_remove_device() call. If the user >>>>>>>>    *            has registered devfreq->nb at a notifier-head, >>>>>>>>    *            this is the time to unregister it. >>>>>>>> - * @freq_table:        Optional list of frequencies to support statistics >>>>>>>> - *            and freq_table must be generated in ascending order. >>>>>>>> - * @max_state:        The size of freq_table. >>>>>>>> - * @total_trans:    Number of devfreq transitions >>>>>>>> - * @trans_table:    Statistics of devfreq transitions >>>>>>>> - * @time_in_state:    Statistics of devfreq states >>>>>>>> - * @last_time:        The last time stats were updated >>>>>>>> - * @stats_lock:        Lock protecting trans_table, time_in_state, >>>>>>>> - *            last_time and total_trans used for statistics >>>>>>>> + * @stats:        Statistics of devfreq states and state transitions >>>>>>>>    */ >>>>>>>>   struct devfreq_dev_profile { >>>>>>>>       unsigned long initial_freq; >>>>>>>> @@ -108,14 +124,7 @@ struct devfreq_dev_profile { >>>>>>>>       int (*get_cur_freq)(struct device *dev, unsigned long *freq); >>>>>>>>       void (*exit)(struct device *dev); >>>>>>>>   -    unsigned long *freq_table; >>>>>>>> -    unsigned int max_state; >>>>>>>> -    /* information for device frequency transition */ >>>>>>>> -    unsigned int total_trans; >>>>>>>> -    unsigned int *trans_table; >>>>>>>> -    u64 *time_in_state; >>>>>>>> -    unsigned long long last_time; >>>>>>>> -    spinlock_t stats_lock; >>>>>>>> +    struct devfreq_stats *stats; >>>>>>>>   }; >>>>>>>>     /** >>>>>>>> >>> >>> _______________________________________________ >>> linux-arm-kernel mailing list >>> linux-arm-kernel@lists.infradead.org >>> https://protect2.fireeye.com/url?k=856913bb-d8f2efd8-856898f4-0cc47a31cdbc-5cb40ce5f31ed8ed&u=http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >>> >> >> > >