From patchwork Fri May 27 04:53:15 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: MyungJoo Ham X-Patchwork-Id: 822932 Received: from smtp1.linux-foundation.org (smtp1.linux-foundation.org [140.211.169.13]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id p4R4tF5j032717 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL) for ; Fri, 27 May 2011 04:55:36 GMT Received: from daredevil.linux-foundation.org (localhost [127.0.0.1]) by smtp1.linux-foundation.org (8.14.2/8.13.5/Debian-3ubuntu1.1) with ESMTP id p4R4reZH019609; Thu, 26 May 2011 21:53:41 -0700 Received: from mailout3.samsung.com (mailout3.samsung.com [203.254.224.33]) by smtp1.linux-foundation.org (8.14.2/8.13.5/Debian-3ubuntu1.1) with ESMTP id p4R4rIgA019526 for ; Thu, 26 May 2011 21:53:25 -0700 Received: from epcpsbgm2.samsung.com (mailout3.samsung.com [203.254.224.33]) by mailout3.samsung.com (Oracle Communications Messaging Exchange Server 7u4-19.01 64bit (built Sep 7 2010)) with ESMTP id <0LLU002W788S1HH0@mailout3.samsung.com> for linux-pm@lists.linux-foundation.org; Fri, 27 May 2011 13:53:17 +0900 (KST) X-AuditID: cbfee61b-b7c62ae0000056ed-ed-4ddf2e3cf7ab Received: from epmmp1 ( [203.254.227.16]) by epcpsbgm2.samsung.com (MMPCPMTA) with SMTP id E1.25.22253.C3E2FDD4; Fri, 27 May 2011 13:53:16 +0900 (KST) Received: from TNRNDGASPAPP1.tn.corp.samsungelectronics.net ([165.213.149.150]) by mmp1.samsung.com (iPlanet Messaging Server 5.2 Patch 2 (built Jul 14 2004)) with ESMTPA id <0LLU000VB88SF8@mmp1.samsung.com> for linux-pm@lists.linux-foundation.org; Fri, 27 May 2011 13:53:16 +0900 (KST) Received: from localhost.localdomain ([165.213.219.116]) by TNRNDGASPAPP1.tn.corp.samsungelectronics.net with Microsoft SMTPSVC(6.0.3790.4675); Fri, 27 May 2011 13:53:15 +0900 Date: Fri, 27 May 2011 13:53:15 +0900 From: MyungJoo Ham In-reply-to: <1306471995-4048-1-git-send-email-myungjoo.ham@samsung.com> To: linux-pm@lists.linux-foundation.org Message-id: <1306471995-4048-3-git-send-email-myungjoo.ham@samsung.com> X-Mailer: git-send-email 1.7.4.1 References: <1306471995-4048-1-git-send-email-myungjoo.ham@samsung.com> X-OriginalArrivalTime: 27 May 2011 04:53:15.0021 (UTC) FILETIME=[FCF763D0:01CC1C29] X-Brightmail-Tracker: AAAAAA== Received-SPF: pass (localhost is always allowed.) X-Spam-Status: No, hits=-12.118 required=5 tests=AWL, BAYES_00, OSDL_HEADER_SUBJECT_BRACKETED, SAMSUNG_WEBMAIL_OSDL X-Spam-Checker-Version: SpamAssassin 3.2.4-osdl_revision__1.47__ X-MIMEDefang-Filter: lf$Revision: 1.188 $ X-Scanned-By: MIMEDefang 2.63 on 140.211.169.21 Cc: Len Brown , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, Kyungmin Park , Thomas Gleixner Subject: [linux-pm] [PATCH v3 3/3] PM / DEVFREQ: add sysfs interface (including user tickling) X-BeenThere: linux-pm@lists.linux-foundation.org X-Mailman-Version: 2.1.9 Precedence: list List-Id: Linux power management List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter1.kernel.org [140.211.167.41]); Fri, 27 May 2011 04:55:36 +0000 (UTC) 1. System-wide sysfs interface - tickle_all R: number of tickle_all execution W: tickle all devfreq devices - min_interval R: devfreq monitoring base interval in ms - monitoring R: shows whether devfreq monitoring is active or not. 2. Device specific sysfs interface - tickle R: number of tickle execution for the device W: tickle the device Signed-off-by: MyungJoo Ham Signed-off-by: Kyungmin Park --- Changed from v2 - add ABI entries for devfreq sysfs interface --- Documentation/ABI/testing/sysfs-devices-devfreq | 21 ++++ Documentation/ABI/testing/sysfs-power | 43 ++++++++ drivers/base/power/devfreq.c | 133 ++++++++++++++++++++++- include/linux/devfreq.h | 3 + 4 files changed, 199 insertions(+), 1 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-devices-devfreq diff --git a/Documentation/ABI/testing/sysfs-devices-devfreq b/Documentation/ABI/testing/sysfs-devices-devfreq new file mode 100644 index 0000000..7f35a64 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-devices-devfreq @@ -0,0 +1,21 @@ +What: /sys/devices/.../devfreq/ +Date: May 2011 +Contact: MyungJoo Ham +Description: + The /sys/device/.../devfreq directory will contain files + that provide interfaces to DEVFREQ for a specific device. + +What: /sys/devices/.../devfreq/tickle +Date: May 2011 +Contact: MyungJoo Ham +Description: + The /sys/devices/.../devfreq/tickle file allows user space + to force the corresponding device to operate at its maximum + operable frequency instaneously and temporarily. After a + designated duration has passed, the operating frequency returns + to normal. When a user reads the tickle entry, it returns + the number of tickle executions for the device. When a user + writes to the tickle entry with the tickle duration in ms, + the effect of device tickling is held for the designated + duration. Note that the duration is rounded-up by + the value DEVFREQ_INTERVAL defined in devfreq.c diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power index b464d12..4d8434b 100644 --- a/Documentation/ABI/testing/sysfs-power +++ b/Documentation/ABI/testing/sysfs-power @@ -172,3 +172,46 @@ Description: Reading from this file will display the current value, which is set to 1 MB by default. + +What: /sys/power/devfreq/ +Date: May 2011 +Contact: MyungJoo Ham +Description: + The /sys/power/devfreq directory will contain files that will + provide a unified interface to the DEVFREQ, a generic DVFS + (dynamic voltage and frequency scaling) framework. + +What: /sys/power/devfreq/tickle_all +Date: May 2011 +Contact: MyungJoo Ham +Description: + The /sys/power/devfreq/tickle_all file allows user space to + force every device with DEVFREQ to operate at the maximum + frequency of the device instaneously and temporarily. After + a designated delay has passed, the operating frequency returns + to normal. If a user reads the tickle_all entry, it returns + the number of tickle_all executions. When writing to the + tickle_all entry, the user should supply with the duration of + tickle in ms (the "designated delay" mentioned before). Then, + the effect of tickle_all will hold for the denoted duration. + Note that the duration is rounded by the monitoring period + defined by DEVFREQ_INTERVAL in /drivers/base/power/devfreq.c. + +What: /sys/power/devfreq/min_interval +Date: May 2011 +Contact: MyungJoo Ham +Description: + The /sys/power/devfreq/min_interval file shows the monitoring + period defined by DEVFREQ_INTERVAL in + /drivers/base/power/devfreq.c. The duration of device tickling + is rounded-up by DEVFREQ_INTERVAL. + +What: /sys/power/devfreq/monitoring +Date: May 2011 +Contact: MyungJoo Ham +Description: + The /sys/power/devfreq/monitoring file shows whether DEVFREQ + is periodically monitoring. Periodic monitoring is activated + if there is a device that wants periodic monitoring for DVFS or + there is a device that is tickled (and the tickling duration is + not yet expired). diff --git a/drivers/base/power/devfreq.c b/drivers/base/power/devfreq.c index 7648a94..709c138 100644 --- a/drivers/base/power/devfreq.c +++ b/drivers/base/power/devfreq.c @@ -40,6 +40,9 @@ static LIST_HEAD(devfreq_list); /* Exclusive access to devfreq_list and its elements */ static DEFINE_MUTEX(devfreq_list_lock); +static struct kobject *devfreq_kobj; +static struct attribute_group dev_attr_group; + /** * find_device_devfreq() - find devfreq struct using device pointer * @dev: device pointer used to lookup device DEVFREQ. @@ -237,6 +240,8 @@ int devfreq_add_device(struct device *dev, struct devfreq_dev_profile *profile, queue_delayed_work(devfreq_wq, &devfreq_work, msecs_to_jiffies(DEVFREQ_INTERVAL)); } + + sysfs_update_group(&dev->kobj, &dev_attr_group); out: mutex_unlock(&devfreq_list_lock); @@ -263,6 +268,8 @@ int devfreq_remove_device(struct device *dev) return -EINVAL; } + sysfs_remove_group(&dev->kobj, &dev_attr_group); + list_del(&devfreq->node); kfree(devfreq); @@ -344,7 +351,7 @@ static int _devfreq_tickle_device(struct devfreq *df, unsigned long delay) if (devfreq_wq && !polling) { polling = true; queue_delayed_work(devfreq_wq, &devfreq_work, - msecs_to_jiffies(DEVFREQ_INTERVAL)); + msecs_to_jiffies(DEVFREQ_INTERVAL)); } return err; @@ -382,6 +389,116 @@ int devfreq_tickle_device(struct device *dev, unsigned long duration_ms) return err; } +static int num_tickle_all; +static ssize_t tickle_all(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + int duration = 0; + struct devfreq *tmp; + unsigned long delay; + + sscanf(buf, "%d", &duration); + if (duration < DEVFREQ_INTERVAL) + duration = DEVFREQ_INTERVAL; + + if (unlikely(IS_ERR_OR_NULL(dev))) { + pr_err("%s: Invalid parameters\n", __func__); + return -EINVAL; + } + + delay = DIV_ROUND_UP(duration, DEVFREQ_INTERVAL); + + mutex_lock(&devfreq_list_lock); + list_for_each_entry(tmp, &devfreq_list, node) { + _devfreq_tickle_device(tmp, delay); + } + mutex_unlock(&devfreq_list_lock); + + num_tickle_all++; + return count; +} + +static ssize_t show_num_tickle_all(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", num_tickle_all); +} + +static ssize_t show_min_interval(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", DEVFREQ_INTERVAL); +} + +static ssize_t show_monitoring(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", monitoring ? 1 : 0); +} + +static DEVICE_ATTR(tickle_all, 0644, show_num_tickle_all, tickle_all); +static DEVICE_ATTR(min_interval, 0444, show_min_interval, NULL); +static DEVICE_ATTR(monitoring, 0444, show_monitoring, NULL); +static struct attribute *devfreq_entries[] = { + &dev_attr_tickle_all.attr, + &dev_attr_min_interval.attr, + &dev_attr_monitoring.attr, + NULL, +}; +static struct attribute_group devfreq_attr_group = { + .name = NULL, + .attrs = devfreq_entries, +}; + +static ssize_t tickle(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + int duration; + struct devfreq *df; + unsigned long delay; + + sscanf(buf, "%d", &duration); + if (duration < DEVFREQ_INTERVAL) + duration = DEVFREQ_INTERVAL; + + if (unlikely(IS_ERR_OR_NULL(dev))) { + pr_err("%s: Invalid parameters\n", __func__); + return -EINVAL; + } + + delay = DIV_ROUND_UP(duration, DEVFREQ_INTERVAL); + + mutex_lock(&devfreq_list_lock); + df = find_device_devfreq(dev); + _devfreq_tickle_device(df, delay); + mutex_unlock(&devfreq_list_lock); + + return count; +} + +static ssize_t show_num_tickle(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct devfreq *df; + + df = find_device_devfreq(dev); + + if (!IS_ERR(df)) + return sprintf(buf, "%d\n", df->num_tickle); + + return PTR_ERR(df); +} + +static DEVICE_ATTR(tickle, 0644, show_num_tickle, tickle); +static struct attribute *dev_entries[] = { + &dev_attr_tickle.attr, + NULL, +}; +static struct attribute_group dev_attr_group = { + .name = "devfreq", + .attrs = dev_entries, +}; + static int __init devfreq_init(void) { mutex_lock(&devfreq_list_lock); @@ -389,6 +506,20 @@ static int __init devfreq_init(void) polling = false; devfreq_wq = create_freezable_workqueue("devfreq_wq"); INIT_DELAYED_WORK_DEFERRABLE(&devfreq_work, devfreq_monitor); + +#ifdef CONFIG_PM + /* Create sysfs */ + devfreq_kobj = kobject_create_and_add("devfreq", power_kobj); + if (!devfreq_kobj) { + pr_err("Unable to create DEVFREQ kobject.\n"); + goto out; + } + if (sysfs_create_group(devfreq_kobj, &devfreq_attr_group)) { + pr_err("Unable to create DEVFREQ sysfs entries.\n"); + goto out; + } +#endif +out: mutex_unlock(&devfreq_list_lock); devfreq_monitor(&devfreq_work.work); diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h index 1ec9a40..69334e7 100644 --- a/include/linux/devfreq.h +++ b/include/linux/devfreq.h @@ -59,6 +59,7 @@ struct devfreq_governor { * at each executino of devfreq_monitor, tickle is decremented. * User may tickle a device-devfreq in order to set maximum * frequency instaneously with some guaranteed duration. + * @num_tickle number of tickle calls. * * This structure stores the DEVFREQ information for a give device. */ @@ -72,6 +73,8 @@ struct devfreq { unsigned long previous_freq; unsigned int next_polling; unsigned int tickle; + + unsigned int num_tickle; }; #if defined(CONFIG_PM_DEVFREQ)