[PATCH] pm: Add runtime PM statistics to sysfs
in [Kernel]
|
From: Arjan van de Ven on 9 Jul 2010 01:50 From: Arjan van de Ven <arjan(a)linux.intel.com> Subject: pm: Add runtime PM statistics to sysfs In order for PowerTOP to be able to report how well the new runtime PM is working for the various drivers, the kernel needs to export some basic statistics in sysfs. This patch adds two sysfs files in the runtime PM domain that expose the total time a device has been active, and the time a device has been suspended. With this PowerTOP can compute the activity percentage Active %age = 100 * (delta active) / (delta active + delta suspended) and present the information to the user. I've written the PowerTOP code (slated for version 1.12) already, and the output looks like this: Runtime Device Power Management statistics Active Device name 10.0% 06:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8101E/RTL8102E Signed-off-by: Arjan van de Ven <arjan(a)linux.intel.com> -- 3 files changed, 58 insertions(+) diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index b0ec0e9..4493775 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -123,6 +123,27 @@ int pm_runtime_idle(struct device *dev) } EXPORT_SYMBOL_GPL(pm_runtime_idle); +void update_pm_runtime_accounting(struct device *dev) +{ + unsigned long now = jiffies; + int delta; + + delta = now - dev->power.accounting_timestamp; + + if (delta < 0) + delta = 0; + + dev->power.accounting_timestamp = now; + + if (dev->power.disable_depth > 0) + return; + + if (dev->power.runtime_status == RPM_SUSPENDED) + dev->power.suspended_jiffies += delta; + else + dev->power.active_jiffies += delta; +} + /** * __pm_runtime_suspend - Carry out run-time suspend of given device. * @dev: Device to suspend. @@ -237,6 +258,7 @@ int __pm_runtime_suspend(struct device *dev, bool from_wq) pm_runtime_cancel_pending(dev); } } else { + update_pm_runtime_accounting(dev); dev->power.runtime_status = RPM_SUSPENDED; pm_runtime_deactivate_timer(dev); @@ -411,6 +433,7 @@ int __pm_runtime_resume(struct device *dev, bool from_wq) } if (retval) { + update_pm_runtime_accounting(dev); dev->power.runtime_status = RPM_SUSPENDED; pm_runtime_cancel_pending(dev); } else { @@ -1077,6 +1100,7 @@ void pm_runtime_init(struct device *dev) dev->power.request_pending = false; dev->power.request = RPM_REQ_NONE; dev->power.deferred_resume = false; + dev->power.accounting_timestamp = jiffies; INIT_WORK(&dev->power.work, pm_runtime_work); dev->power.timer_expires = 0; diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c index a4c33bc..f45c316 100644 --- a/drivers/base/power/sysfs.c +++ b/drivers/base/power/sysfs.c @@ -6,6 +6,7 @@ #include <linux/string.h> #include <linux/pm_runtime.h> #include <asm/atomic.h> +#include <linux/jiffies.h> #include "power.h" /* @@ -190,9 +191,34 @@ static ssize_t rtpm_status_show(struct device *dev, return -EIO; } +static ssize_t rtpm_active_time_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int ret; + spin_lock_irq(&dev->power.lock); + update_pm_runtime_accounting(dev); + ret = sprintf(buf, "%i\n", jiffies_to_msecs(dev->power.active_jiffies)); + spin_unlock_irq(&dev->power.lock); + return ret; +} + +static ssize_t rtpm_suspended_time_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int ret; + spin_lock_irq(&dev->power.lock); + update_pm_runtime_accounting(dev); + ret = sprintf(buf, "%i\n", + jiffies_to_msecs(dev->power.suspended_jiffies)); + spin_unlock_irq(&dev->power.lock); + return ret; +} + static DEVICE_ATTR(runtime_usage, 0444, rtpm_usagecount_show, NULL); static DEVICE_ATTR(runtime_active_kids, 0444, rtpm_children_show, NULL); static DEVICE_ATTR(runtime_status, 0444, rtpm_status_show, NULL); +static DEVICE_ATTR(runtime_active_time, 0444, rtpm_active_time_show, NULL); +static DEVICE_ATTR(runtime_suspended_time, 0444, rtpm_suspended_time_show, NULL); static DEVICE_ATTR(runtime_enabled, 0444, rtpm_enabled_show, NULL); #endif @@ -234,6 +260,8 @@ static struct attribute * power_attrs[] = { &dev_attr_async.attr, #ifdef CONFIG_PM_RUNTIME &dev_attr_runtime_usage.attr, + &dev_attr_runtime_suspended_time.attr, + &dev_attr_runtime_active_time.attr, &dev_attr_runtime_active_kids.attr, &dev_attr_runtime_status.attr, &dev_attr_runtime_enabled.attr, diff --git a/include/linux/pm.h b/include/linux/pm.h index 8e258c7..dca597f 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -476,9 +476,15 @@ struct dev_pm_info { enum rpm_request request; enum rpm_status runtime_status; int runtime_error; + unsigned long active_jiffies; + unsigned long suspended_jiffies; + unsigned long accounting_timestamp; #endif }; +extern void update_pm_runtime_accounting(struct device *dev); + + /* * The PM_EVENT_ messages are also used by drivers implementing the legacy * suspend framework, based on the ->suspend() and ->resume() callbacks common -- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Alan Stern on 9 Jul 2010 11:10 On Thu, 8 Jul 2010, Arjan van de Ven wrote: > From: Arjan van de Ven <arjan(a)linux.intel.com> > Subject: pm: Add runtime PM statistics to sysfs > > In order for PowerTOP to be able to report how well the new runtime PM is working > for the various drivers, the kernel needs to export some basic statistics in sysfs. > > This patch adds two sysfs files in the runtime PM domain that expose the > total time a device has been active, and the time a device has been suspended. > > With this PowerTOP can compute the activity percentage > > Active %age = 100 * (delta active) / (delta active + delta suspended) > > and present the information to the user. > > I've written the PowerTOP code (slated for version 1.12) already, and the output looks > like this: > > Runtime Device Power Management statistics > Active Device name > 10.0% 06:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8101E/RTL8102E > @@ -411,6 +433,7 @@ int __pm_runtime_resume(struct device *dev, bool from_wq) > } > > if (retval) { > + update_pm_runtime_accounting(dev); > dev->power.runtime_status = RPM_SUSPENDED; > pm_runtime_cancel_pending(dev); > } else { This line was added in the wrong place. It belongs either before the "if (retval) {" or after the "} else {". Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Alan Stern on 9 Jul 2010 11:20 On Fri, 9 Jul 2010, Alan Stern wrote: > On Thu, 8 Jul 2010, Arjan van de Ven wrote: > > > From: Arjan van de Ven <arjan(a)linux.intel.com> > > Subject: pm: Add runtime PM statistics to sysfs > > > > In order for PowerTOP to be able to report how well the new runtime PM is working > > for the various drivers, the kernel needs to export some basic statistics in sysfs. > > > > This patch adds two sysfs files in the runtime PM domain that expose the > > total time a device has been active, and the time a device has been suspended. > > > > With this PowerTOP can compute the activity percentage > > > > Active %age = 100 * (delta active) / (delta active + delta suspended) > > > > and present the information to the user. > > > > I've written the PowerTOP code (slated for version 1.12) already, and the output looks > > like this: > > > > Runtime Device Power Management statistics > > Active Device name > > 10.0% 06:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8101E/RTL8102E > > > > @@ -411,6 +433,7 @@ int __pm_runtime_resume(struct device *dev, bool from_wq) > > } > > > > if (retval) { > > + update_pm_runtime_accounting(dev); > > dev->power.runtime_status = RPM_SUSPENDED; > > pm_runtime_cancel_pending(dev); > > } else { > > This line was added in the wrong place. It belongs either before the > "if (retval) {" or after the "} else {". Whoops, sorry, my mistake. It doesn't belong here at all. It belongs considerably earlier in the function, before the line: dev->power.runtime_status = RPM_RESUMING; This is because update_pm_runtime_accounting() doesn't take into account the existence of the RPM_RESUMING and RPM_SUSPENDING states; it treats them all the same as RPM_ACTIVE. Also, it looks like you forgot to add a call in __pm_runtime_set_status(). Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Arjan van de Ven on 10 Jul 2010 12:00 On Fri, 9 Jul 2010 11:11:06 -0400 (EDT) Alan Stern <stern(a)rowland.harvard.edu> wrote: > On Fri, 9 Jul 2010, Alan Stern wrote: > > > On Thu, 8 Jul 2010, Arjan van de Ven wrote: > > > > > From: Arjan van de Ven <arjan(a)linux.intel.com> > > > Subject: pm: Add runtime PM statistics to sysfs > > > > > > In order for PowerTOP to be able to report how well the new > > > runtime PM is working for the various drivers, the kernel needs > > > to export some basic statistics in sysfs. > > > > > > This patch adds two sysfs files in the runtime PM domain that > > > expose the total time a device has been active, and the time a > > > device has been suspended. > > > > > > With this PowerTOP can compute the activity percentage > > > > > > Active %age = 100 * (delta active) / (delta active + delta > > > suspended) > > > > > > and present the information to the user. > > > > > > I've written the PowerTOP code (slated for version 1.12) already, > > > and the output looks like this: > > > > > > Runtime Device Power Management statistics > > > Active Device name > > > 10.0% 06:00.0 Ethernet controller: Realtek Semiconductor > > > Co., Ltd. RTL8101E/RTL8102E > > > > > > > @@ -411,6 +433,7 @@ int __pm_runtime_resume(struct device *dev, > > > bool from_wq) } > > > > > > if (retval) { > > > + update_pm_runtime_accounting(dev); > > > dev->power.runtime_status = RPM_SUSPENDED; > > > pm_runtime_cancel_pending(dev); > > > } else { > > > > This line was added in the wrong place. It belongs either before > > the "if (retval) {" or after the "} else {". > > Whoops, sorry, my mistake. It doesn't belong here at all. It > belongs considerably earlier in the function, before the line: you are correct. I'll fix it, I think I'll make a small helper that does the account and assignment in one place, so that we then can have a rule that nobody updates this field without calling the function -- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Arjan van de Ven on 10 Jul 2010 12:30 On Fri, 9 Jul 2010 11:11:06 -0400 (EDT) Alan Stern <stern(a)rowland.harvard.edu> wrote: > > This is because update_pm_runtime_accounting() doesn't take into > account the existence of the RPM_RESUMING and RPM_SUSPENDING states; > it treats them all the same as RPM_ACTIVE. this is by design fwiw; I'm considering the time spent going in and out of suspend as "active", it's a little on the conservative side, but the underlying assumption is that you're still burning power until you're really suspended. Better to be conservative and not count it as really suspended.... -- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
|
Pages: 1 Prev: linux-next: Tree for July 9 Next: [PATCH] mtdpart: memory accessor interface for MTD layer |