linaro-dev September 2012

linaro-dev@lists.linaro.org

84 participants
100 discussions

by Dechesne, Nicolas

hi there, at HK connect i learned about the ARM energy probe ( http://www.arm.com/about/newsroom/arm-enables-energy-aware-coding-with-the-…). Since that we ordered some probes, and I was wondering if someone is working in linaro on enabling power measurements? I would be interested in DS5 or even command line tools to retrieve information, ideally from Panda... thx

11 years, 8 months

[PULL REQUEST]: ARM: perf: multi-PMU support

by Sudeep KarkadaNagesha

Hi Viresh, Please pull the following changes for the multiple CPU PMU support (re-based to v3.6-rc5). Few patches in the list below are already queued up for 3.7. Since you have access to internal repository, I am posting patches on the same. Let me know if you face any issues. --------------------------------------------------------------------------- The following changes since commit 55d512e245bc7699a8800e23df1a24195dd08217: Linux 3.6-rc5 (2012-09-08 16:43:45 -0700) are available in the git repository at: ssh://username@pdsw-ci.cambridge.arm.com:29418/kernel.git multi_pmu_v1 for you to fetch changes up to ec3a17b94b09870468db575b95fa92c50c9cc778: ARM: ux500: Fix build error due to missing include of asm/pmu.h in cpu-db8500.c (2012-09-14 10:00:47 +0100) ---------------------------------------------------------------- Axel Lin (1): ARM: ux500: Fix build error due to missing include of asm/pmu.h in cpu-db8500.c Jon Hunter (1): ARM: PMU: Add runtime PM Support Lorenzo Pieralisi (1): ARM: kernel: provide cluster to logical cpu mask mapping API Sudeep KarkadaNagesha (9): ARM: pmu: remove arm_pmu_type enumeration ARM: perf: move irq registration into pmu implementation ARM: perf: allocation of cpu_pmu at init time ARM: perf: change multiple arm_pmu function parameters to struct perf_event ARM: perf: rework on armv7_pmnc_counter_valid ARM: perf: define per-cpu arm_pmu instead of a single global pointer ARM: perf: register the init functions with the bindings ARM: perf: add support for per-cluster/multiple PMUs ARM: perf: save/restore pmu registers in pm notifier Will Deacon (6): ARM: perf: add devicetree bindings for 11MPcore, A5, A7 and A15 PMUs ARM: pmu: remove unused reservation mechanism ARM: perf: remove mysterious compiler barrier ARM: perf: probe devicetree in preference to current CPU ARM: perf: prepare for moving CPU PMU code into separate file ARM: perf: move CPU-specific PMU handling code into separate file Documentation/devicetree/bindings/arm/pmu.txt | 7 + MAINTAINERS | 1 - arch/arm/Kconfig | 8 +- arch/arm/include/asm/perf_event.h | 9 +- arch/arm/include/asm/pmu.h | 128 ++++---- arch/arm/include/asm/topology.h | 3 + arch/arm/kernel/Makefile | 4 +- arch/arm/kernel/perf_event.c | 391 +++++-------------------- arch/arm/kernel/perf_event_cpu.c | 351 ++++++++++++++++++++++ arch/arm/kernel/perf_event_v6.c | 152 +++++----- arch/arm/kernel/perf_event_v7.c | 330 ++++++++++++--------- arch/arm/kernel/perf_event_xscale.c | 179 ++++++----- arch/arm/kernel/pmu.c | 36 --- arch/arm/kernel/topology.c | 27 ++ arch/arm/mach-bcmring/arch.c | 3 +- arch/arm/mach-omap2/devices.c | 3 +- arch/arm/mach-pxa/devices.c | 3 +- arch/arm/mach-realview/realview_eb.c | 3 +- arch/arm/mach-realview/realview_pb1176.c | 3 +- arch/arm/mach-realview/realview_pb11mp.c | 3 +- arch/arm/mach-realview/realview_pba8.c | 3 +- arch/arm/mach-realview/realview_pbx.c | 3 +- arch/arm/mach-tegra/devices.c | 3 +- arch/arm/mach-ux500/cpu-db8500.c | 4 +- arch/arm/mach-vexpress/ct-ca9x4.c | 3 +- arch/arm/plat-iop/pmu.c | 3 +- arch/arm/plat-samsung/devs.c | 3 +- 27 files changed, 916 insertions(+), 750 deletions(-) create mode 100644 arch/arm/kernel/perf_event_cpu.c delete mode 100644 arch/arm/kernel/pmu.c

11 years, 8 months

[PATCH] linaro/configs: ubuntu: Disable support for generic OHCI platform driver

by Tushar Behera

OHCI-HCD driver does not support multiple SoC drivers during the compile time. Hence the generic driver should be disabled in ubuntu.conf and related OHCI Soc drivers should be enabled in respective board config files. Signed-off-by: Tushar Behera <tushar.behera(a)linaro.org> --- linaro/configs/ubuntu.conf | 1 - 1 files changed, 0 insertions(+), 1 deletions(-) diff --git a/linaro/configs/ubuntu.conf b/linaro/configs/ubuntu.conf index 5d0a372..88e58df 100644 --- a/linaro/configs/ubuntu.conf +++ b/linaro/configs/ubuntu.conf @@ -1556,7 +1556,6 @@ CONFIG_USB_OXU210HP_HCD=m CONFIG_USB_ISP116X_HCD=m CONFIG_USB_ISP1760_HCD=m CONFIG_USB_OHCI_HCD=y -CONFIG_USB_OHCI_HCD_PLATFORM=y CONFIG_USB_OHCI_LITTLE_ENDIAN=y CONFIG_USB_U132_HCD=m CONFIG_USB_SL811_HCD=m -- 1.7.4.1

11 years, 8 months

[PATCH 1/2] UBUNTU: dm-raid4-5: rename split_io to max_io_len

by Tushar Behera

Commit 542f90381422 ("dm: support non power of two target max_io_len") renames struct dm_target:split_io variable to max_io_len. Signed-off-by: Tushar Behera <tushar.behera(a)linaro.org> --- ubuntu/dm-raid4-5/dm-raid4-5.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/ubuntu/dm-raid4-5/dm-raid4-5.c b/ubuntu/dm-raid4-5/dm-raid4-5.c index e05b0e1..e69ab44 100644 --- a/ubuntu/dm-raid4-5/dm-raid4-5.c +++ b/ubuntu/dm-raid4-5/dm-raid4-5.c @@ -4073,7 +4073,7 @@ static int raid_ctr(struct dm_target *ti, unsigned argc, char **argv) * Make sure that dm core only hands maximum io size * length down and pays attention to io boundaries. */ - ti->split_io = rs->set.io_size; + ti->max_io_len = rs->set.io_size; ti->private = rs; /* Initialize work queue to handle this RAID set's io. */ -- 1.7.4.1

11 years, 8 months

[RFC] power: opp: rcu reclaim

by Vincent Guittot

synchronize_rcu blocks the caller of opp_enable/disbale for a complete grace period. This blocking duration prevents any intensive use of the functions. Replace synchronize_rcu by call_rcu which will call our function for freeing the old opp element. The duration of opp_enable and opp_disable will be no more dependant of the grace period. Signed-off-by: Vincent Guittot <vincent.guittot(a)linaro.org> --- drivers/base/power/opp.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index ac993ea..49e4626 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -64,6 +64,7 @@ struct opp { unsigned long u_volt; struct device_opp *dev_opp; + struct rcu_head head; }; /** @@ -441,6 +442,17 @@ int opp_add(struct device *dev, unsigned long freq, unsigned long u_volt) } /** + * opp_free_rcu() - helper to clear the struct opp when grace period has + * elapsed without blocking the the caller of opp_set_availability + */ +static void opp_free_rcu(struct rcu_head *head) +{ + struct opp *opp = container_of(head, struct opp, head); + + kfree(opp); +} + +/** * opp_set_availability() - helper to set the availability of an opp * @dev: device for which we do this operation * @freq: OPP frequency to modify availability @@ -511,7 +523,7 @@ static int opp_set_availability(struct device *dev, unsigned long freq, list_replace_rcu(&opp->node, &new_opp->node); mutex_unlock(&dev_opp_list_lock); - synchronize_rcu(); + call_rcu(&opp->head, opp_free_rcu); /* Notify the change of the OPP availability */ if (availability_req) @@ -521,13 +533,10 @@ static int opp_set_availability(struct device *dev, unsigned long freq, srcu_notifier_call_chain(&dev_opp->head, OPP_EVENT_DISABLE, new_opp); - /* clean up old opp */ - new_opp = opp; - goto out; + return 0; unlock: mutex_unlock(&dev_opp_list_lock); -out: kfree(new_opp); return r; } -- 1.7.9.5

11 years, 8 months

llct "stable" trees

by Andy Green

Hi - We've been getting some good mileage from the llct-based tilt-3.4 history tree the last months. However a couple of points have been raised by TI which really boil down to being about the deal with llct post-release. We know that it goes on mutating and tracking as it should, but the release-specific version, like "linux-linaro-3.4" just sits there afaik. The points raised were: 1) Can we have linux stable point release content in tilt-3.4? Rather than my doing it, isn't it better to add it to llc-3.4 and merge it on the lt history tree periodically? That way every lt can get them from one place. 2) What's the deal with things that were the latest and greatest at that time, ie, the best "CMA" or whatever series was in tracking, but after it got copied out to be linux-linaro-core-3.4, horrible bugs were fixed in linux-linaro-tracking? What's happening is that TI are sticking with these releases for a fair time as the basis for their release to customers. I can see there's tension between tracking-style fix it for the future, and backport to old and crusty things, there's also issue of testing, but there must be some cases where this makes some sense. Again people looking after the feature tree for llct are best placed to make those calls about, "hm, that looks like it should maybe also go on the last couple of llc release trees". What do you think about this? -Andy -- Andy Green | TI Landing Team Leader Linaro.org │ Open source software for ARM SoCs | Follow Linaro http://facebook.com/pages/Linaro/155974581091106 - http://twitter.com/#!/linaroorg - http://linaro.org/linaro-blog

11 years, 8 months

[PATCH v2 0/3] devfreq: Add support for devices which can idle

by Rajagopal Venkat

From: Rajagopal Venkat <rajagopal.venkat(a)linaro.org> This patchset updates devfreq core to add support for devices which can idle. When device idleness is detected perhaps through runtime-pm, need some mechanism to suspend devfreq load monitoring and resume when device is back online. patch 1 introduce core design changes - per device work, decouple delayed work from core and event based interaction. patch 2 add devfreq suspend and resume apis. patch 3 add new sysfs attribute for governor predicted next target frequency and callback for current device frequency. The existing devfreq apis are kept intact. Two new apis devfreq_suspend_device() and devfreq_resume_device() are added to support suspend/resume of device devfreq. Changes since v1: - revised locking mechanism - added kerneldoc comments for load monitoring helper functions - Fixed minor review comments -- Rajagopal Venkat (3): devfreq: Core updates to support devices which can idle devfreq: Add suspend and resume apis devfreq: Add current freq callback in device profile Documentation/ABI/testing/sysfs-class-devfreq | 15 +- drivers/devfreq/devfreq.c | 413 +++++++++++--------------- drivers/devfreq/governor.h | 11 + drivers/devfreq/governor_performance.c | 16 +- drivers/devfreq/governor_powersave.c | 16 +- drivers/devfreq/governor_simpleondemand.c | 40 +++ drivers/devfreq/governor_userspace.c | 23 +- include/linux/devfreq.h | 46 ++- 8 files changed, 291 insertions(+), 289 deletions(-) -- 1.7.11.3

11 years, 8 months

Re: [PATCH 1/3] devfreq: core updates to support devices which can idle

by 함명주

> Prepare devfreq core framework to support devices which > can idle. When device idleness is detected perhaps through > runtime-pm, need some mechanism to suspend devfreq load > monitoring and resume back when device is online. Present > code continues monitoring unless device is removed from > devfreq core. > > This patch introduces following design changes, > > - use per device work instead of global work to monitor device > load. This enables suspend/resume of device devfreq and > reduces monitoring code complexity. > - decouple delayed work based load monitoring logic from core > by introducing helpers functions to be used by governors. This > provides flexibility for governors either to use delayed work > based monitoring functions or to implement their own mechanism. > - devfreq core interacts with governors via events to perform > specific actions. These events include start/stop devfreq. > This sets ground for adding suspend/resume events. > > The devfreq apis are not modified and are kept intact. Hello, Please revise locking mechanism along with event handler. It appears that we need to do mutex_lock(&devfreq->lock) before calling devfreq->governor->event_handler(); Or at least, userspace_init and userspace_exit functions require mutex_lock. Event_handler callback won't want the properties in devfreq to be changed externally during its execution. Plus, please edit Documentation/ABI entry (central_polling is being removed) Other than that, it looks fine. Cheers! MyungJoo > > Signed-off-by: Rajagopal Venkat <rajagopal.venkat(a)linaro.org> > --- > drivers/devfreq/devfreq.c | 376 ++++++++++-------------------- > drivers/devfreq/governor.h | 9 + > drivers/devfreq/governor_performance.c | 16 +- > drivers/devfreq/governor_powersave.c | 16 +- > drivers/devfreq/governor_simpleondemand.c | 33 +++ > drivers/devfreq/governor_userspace.c | 23 +- > include/linux/devfreq.h | 31 +-- > 7 files changed, 220 insertions(+), 284 deletions(-) > > diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c > index b146d76..be524c7 100644 > --- a/drivers/devfreq/devfreq.c > +++ b/drivers/devfreq/devfreq.c > @@ -30,17 +30,11 @@ > struct class *devfreq_class; > > /* > - * devfreq_work periodically monitors every registered device. > - * The minimum polling interval is one jiffy. The polling interval is > - * determined by the minimum polling period among all polling devfreq > - * devices. The resolution of polling interval is one jiffy. > + * devfreq core provides delayed work based load monitoring helper > + * functions. Governors can use these or can implement their own > + * monitoring mechanism. > */ > -static bool polling; > static struct workqueue_struct *devfreq_wq; > -static struct delayed_work devfreq_work; > - > -/* wait removing if this is to be removed */ > -static struct devfreq *wait_remove_device; > > /* The list of all device-devfreq */ > static LIST_HEAD(devfreq_list); > @@ -72,6 +66,8 @@ static struct devfreq *find_device_devfreq(struct device *dev) > return ERR_PTR(-ENODEV); > } > > +/* Load monitoring helper functions for governors use */ > + > /** > * update_devfreq() - Reevaluate the device and configure frequency. > * @devfreq: the devfreq instance. > @@ -121,6 +117,90 @@ int update_devfreq(struct devfreq *devfreq) > } > > /** > + * devfreq_monitor() - Periodically poll devfreq objects. > + * @work: the work struct used to run devfreq_monitor periodically. > + * > + */ > +static void devfreq_monitor(struct work_struct *work) > +{ > + int err; > + struct devfreq *devfreq = container_of(work, > + struct devfreq, work.work); > + > + mutex_lock(&devfreq->lock); > + err = update_devfreq(devfreq); > + mutex_unlock(&devfreq->lock); > + if (err) > + dev_err(&devfreq->dev, "dvfs failed with (%d) error\n", err); > + > + queue_delayed_work(devfreq_wq, &devfreq->work, > + msecs_to_jiffies(devfreq->profile->polling_ms)); > +} > + > +/** > + * devfreq_monitor_start() - Start load monitoring of devfreq instance > + * using default delayed work > + * @devfreq: the devfreq instance. > + * > + * Returns 0 if monitoring started, non-zero otherwise. > + * Note: This function is exported for governors. > + */ > +int devfreq_monitor_start(struct devfreq *devfreq) > +{ > + INIT_DEFERRABLE_WORK(&devfreq->work, devfreq_monitor); > + return !queue_delayed_work(devfreq_wq, &devfreq->work, > + msecs_to_jiffies(devfreq->profile->polling_ms)); > +} > + > +/** > + * devfreq_monitor_stop() - Stop load monitoring of a devfreq instance > + * @devfreq: the devfreq instance. > + * > + * Note: This function is exported for governors. > + */ > +void devfreq_monitor_stop(struct devfreq *devfreq) > +{ > + cancel_delayed_work_sync(&devfreq->work); > +} > + > +/** > + * devfreq_monitor_suspend() - Suspend load monitoring of a devfreq instance > + * @devfreq: the devfreq instance. > + * > + * Note: This function is exported for governors. > + */ > +int devfreq_monitor_suspend(struct devfreq *devfreq) > +{ > + int ret = -EPERM; > + > + if (delayed_work_pending(&devfreq->work)) { > + cancel_delayed_work_sync(&devfreq->work); > + ret = 0; > + } > + > + return ret; > +} > + > +/** > + * devfreq_monitor_resume() - Resume load monitoring of a devfreq instance > + * @devfreq: the devfreq instance. > + * > + * Returns 0 if monitoring re-started, non-zero otherwise. > + * Note: This function is exported for governors. > + */ > +int devfreq_monitor_resume(struct devfreq *devfreq) > +{ > + int ret = -EPERM; > + > + if (!delayed_work_pending(&devfreq->work)) { > + ret = !queue_delayed_work(devfreq_wq, &devfreq->work, > + msecs_to_jiffies(devfreq->profile->polling_ms)); > + } > + > + return ret; > +} > + > +/** > * devfreq_notifier_call() - Notify that the device frequency requirements > * has been changed out of devfreq framework. > * @nb the notifier_block (supposed to be devfreq->nb) > @@ -143,59 +223,33 @@ static int devfreq_notifier_call(struct notifier_block *nb, unsigned long type, > } > > /** > - * _remove_devfreq() - Remove devfreq from the device. > + * _remove_devfreq() - Remove devfreq from the devfreq list and > + release its resources. > * @devfreq: the devfreq struct > * @skip: skip calling device_unregister(). > - * > - * Note that the caller should lock devfreq->lock before calling > - * this. _remove_devfreq() will unlock it and free devfreq > - * internally. devfreq_list_lock should be locked by the caller > - * as well (not relased at return) > - * > - * Lock usage: > - * devfreq->lock: locked before call. > - * unlocked at return (and freed) > - * devfreq_list_lock: locked before call. > - * kept locked at return. > - * if devfreq is centrally polled. > - * > - * Freed memory: > - * devfreq > */ > static void _remove_devfreq(struct devfreq *devfreq, bool skip) > { > - if (!mutex_is_locked(&devfreq->lock)) { > - WARN(true, "devfreq->lock must be locked by the caller.\n"); > - return; > - } > - if (!devfreq->governor->no_central_polling && > - !mutex_is_locked(&devfreq_list_lock)) { > - WARN(true, "devfreq_list_lock must be locked by the caller.\n"); > + mutex_lock(&devfreq_list_lock); > + if (IS_ERR(find_device_devfreq(devfreq->dev.parent))) { > + mutex_unlock(&devfreq_list_lock); > + dev_warn(&devfreq->dev, "releasing devfreq which doesn't exist\n"); > return; > } > + list_del(&devfreq->node); > + mutex_unlock(&devfreq_list_lock); > > - if (devfreq->being_removed) > - return; > - > - devfreq->being_removed = true; > + devfreq->governor->event_handler(devfreq, DEVFREQ_GOV_STOP); > > if (devfreq->profile->exit) > devfreq->profile->exit(devfreq->dev.parent); > > - if (devfreq->governor->exit) > - devfreq->governor->exit(devfreq); > - > if (!skip && get_device(&devfreq->dev)) { > device_unregister(&devfreq->dev); > put_device(&devfreq->dev); > } > > - if (!devfreq->governor->no_central_polling) > - list_del(&devfreq->node); > - > - mutex_unlock(&devfreq->lock); > mutex_destroy(&devfreq->lock); > - > kfree(devfreq); > } > > @@ -210,130 +264,8 @@ static void _remove_devfreq(struct devfreq *devfreq, bool skip) > static void devfreq_dev_release(struct device *dev) > { > struct devfreq *devfreq = to_devfreq(dev); > - bool central_polling = !devfreq->governor->no_central_polling; > - > - /* > - * If devfreq_dev_release() was called by device_unregister() of > - * _remove_devfreq(), we cannot mutex_lock(&devfreq->lock) and > - * being_removed is already set. This also partially checks the case > - * where devfreq_dev_release() is called from a thread other than > - * the one called _remove_devfreq(); however, this case is > - * dealt completely with another following being_removed check. > - * > - * Because being_removed is never being > - * unset, we do not need to worry about race conditions on > - * being_removed. > - */ > - if (devfreq->being_removed) > - return; > - > - if (central_polling) > - mutex_lock(&devfreq_list_lock); > - > - mutex_lock(&devfreq->lock); > - > - /* > - * Check being_removed flag again for the case where > - * devfreq_dev_release() was called in a thread other than the one > - * possibly called _remove_devfreq(). > - */ > - if (devfreq->being_removed) { > - mutex_unlock(&devfreq->lock); > - goto out; > - } > > - /* devfreq->lock is unlocked and removed in _removed_devfreq() */ > _remove_devfreq(devfreq, true); > - > -out: > - if (central_polling) > - mutex_unlock(&devfreq_list_lock); > -} > - > -/** > - * devfreq_monitor() - Periodically poll devfreq objects. > - * @work: the work struct used to run devfreq_monitor periodically. > - * > - */ > -static void devfreq_monitor(struct work_struct *work) > -{ > - static unsigned long last_polled_at; > - struct devfreq *devfreq, *tmp; > - int error; > - unsigned long jiffies_passed; > - unsigned long next_jiffies = ULONG_MAX, now = jiffies; > - struct device *dev; > - > - /* Initially last_polled_at = 0, polling every device at bootup */ > - jiffies_passed = now - last_polled_at; > - last_polled_at = now; > - if (jiffies_passed == 0) > - jiffies_passed = 1; > - > - mutex_lock(&devfreq_list_lock); > - list_for_each_entry_safe(devfreq, tmp, &devfreq_list, node) { > - mutex_lock(&devfreq->lock); > - dev = devfreq->dev.parent; > - > - /* Do not remove tmp for a while */ > - wait_remove_device = tmp; > - > - if (devfreq->governor->no_central_polling || > - devfreq->next_polling == 0) { > - mutex_unlock(&devfreq->lock); > - continue; > - } > - mutex_unlock(&devfreq_list_lock); > - > - /* > - * Reduce more next_polling if devfreq_wq took an extra > - * delay. (i.e., CPU has been idled.) > - */ > - if (devfreq->next_polling <= jiffies_passed) { > - error = update_devfreq(devfreq); > - > - /* Remove a devfreq with an error. */ > - if (error && error != -EAGAIN) { > - > - dev_err(dev, "Due to update_devfreq error(%d), devfreq(%s) is removed from the device\n", > - error, devfreq->governor->name); > - > - /* > - * Unlock devfreq before locking the list > - * in order to avoid deadlock with > - * find_device_devfreq or others > - */ > - mutex_unlock(&devfreq->lock); > - mutex_lock(&devfreq_list_lock); > - /* Check if devfreq is already removed */ > - if (IS_ERR(find_device_devfreq(dev))) > - continue; > - mutex_lock(&devfreq->lock); > - /* This unlocks devfreq->lock and free it */ > - _remove_devfreq(devfreq, false); > - continue; > - } > - devfreq->next_polling = devfreq->polling_jiffies; > - } else { > - devfreq->next_polling -= jiffies_passed; > - } > - > - if (devfreq->next_polling) > - next_jiffies = (next_jiffies > devfreq->next_polling) ? > - devfreq->next_polling : next_jiffies; > - > - mutex_unlock(&devfreq->lock); > - mutex_lock(&devfreq_list_lock); > - } > - wait_remove_device = NULL; > - mutex_unlock(&devfreq_list_lock); > - > - if (next_jiffies > 0 && next_jiffies < ULONG_MAX) { > - polling = true; > - queue_delayed_work(devfreq_wq, &devfreq_work, next_jiffies); > - } else { > - polling = false; > - } > } > > /** > @@ -357,16 +289,13 @@ struct devfreq *devfreq_add_device(struct device *dev, > return ERR_PTR(-EINVAL); > } > > - > - if (!governor->no_central_polling) { > - mutex_lock(&devfreq_list_lock); > - devfreq = find_device_devfreq(dev); > - mutex_unlock(&devfreq_list_lock); > - if (!IS_ERR(devfreq)) { > - dev_err(dev, "%s: Unable to create devfreq for the device. It already has one.\n", __func__); > - err = -EINVAL; > - goto err_out; > - } > + mutex_lock(&devfreq_list_lock); > + devfreq = find_device_devfreq(dev); > + mutex_unlock(&devfreq_list_lock); > + if (!IS_ERR(devfreq)) { > + dev_err(dev, "%s: Unable to create devfreq for the device. It already has one.\n", __func__); > + err = -EINVAL; > + goto err_out; > } > > devfreq = kzalloc(sizeof(struct devfreq), GFP_KERNEL); > @@ -386,48 +315,40 @@ struct devfreq *devfreq_add_device(struct device *dev, > devfreq->governor = governor; > devfreq->previous_freq = profile->initial_freq; > devfreq->data = data; > - devfreq->next_polling = devfreq->polling_jiffies > - = msecs_to_jiffies(devfreq->profile->polling_ms); > devfreq->nb.notifier_call = devfreq_notifier_call; > > dev_set_name(&devfreq->dev, dev_name(dev)); > err = device_register(&devfreq->dev); > if (err) { > put_device(&devfreq->dev); > + mutex_unlock(&devfreq->lock); > goto err_dev; > } > > - if (governor->init) > - err = governor->init(devfreq); > - if (err) > - goto err_init; > - > mutex_unlock(&devfreq->lock); > > - if (governor->no_central_polling) > - goto out; > - > mutex_lock(&devfreq_list_lock); > - > list_add(&devfreq->node, &devfreq_list); > + mutex_unlock(&devfreq_list_lock); > > - if (devfreq_wq && devfreq->next_polling && !polling) { > - polling = true; > - queue_delayed_work(devfreq_wq, &devfreq_work, > - devfreq->next_polling); > + err = devfreq->governor->event_handler(devfreq, DEVFREQ_GOV_START); > + if (err) { > + dev_err(dev, "%s: Unable to start governor for the device\n", > + __func__); > + goto err_init; > } > - mutex_unlock(&devfreq_list_lock); > -out: > + > return devfreq; > > err_init: > + list_del(&devfreq->node); > device_unregister(&devfreq->dev); > err_dev: > - mutex_unlock(&devfreq->lock); > kfree(devfreq); > err_out: > return ERR_PTR(err); > } > +EXPORT_SYMBOL(devfreq_add_device); > > /** > * devfreq_remove_device() - Remove devfreq feature from a device. > @@ -435,30 +356,14 @@ err_out: > */ > int devfreq_remove_device(struct devfreq *devfreq) > { > - bool central_polling; > - > if (!devfreq) > return -EINVAL; > > - central_polling = !devfreq->governor->no_central_polling; > - > - if (central_polling) { > - mutex_lock(&devfreq_list_lock); > - while (wait_remove_device == devfreq) { > - mutex_unlock(&devfreq_list_lock); > - schedule(); > - mutex_lock(&devfreq_list_lock); > - } > - } > - > - mutex_lock(&devfreq->lock); > - _remove_devfreq(devfreq, false); /* it unlocks devfreq->lock */ > - > - if (central_polling) > - mutex_unlock(&devfreq_list_lock); > + _remove_devfreq(devfreq, false); > > return 0; > } > +EXPORT_SYMBOL(devfreq_remove_device); > > static ssize_t show_governor(struct device *dev, > struct device_attribute *attr, char *buf) > @@ -492,33 +397,15 @@ static ssize_t store_polling_interval(struct device *dev, > > mutex_lock(&df->lock); > df->profile->polling_ms = value; > - df->next_polling = df->polling_jiffies > - = msecs_to_jiffies(value); > mutex_unlock(&df->lock); > > + df->governor->event_handler(df, DEVFREQ_GOV_INTERVAL); > ret = count; > > - if (df->governor->no_central_polling) > - goto out; > - > - mutex_lock(&devfreq_list_lock); > - if (df->next_polling > 0 && !polling) { > - polling = true; > - queue_delayed_work(devfreq_wq, &devfreq_work, > - df->next_polling); > - } > - mutex_unlock(&devfreq_list_lock); > out: > return ret; > } > > -static ssize_t show_central_polling(struct device *dev, > - struct device_attribute *attr, char *buf) > -{ > - return sprintf(buf, "%d\n", > - !to_devfreq(dev)->governor->no_central_polling); > -} > - > static ssize_t store_min_freq(struct device *dev, struct device_attribute *attr, > const char *buf, size_t count) > { > @@ -590,7 +477,6 @@ static ssize_t show_max_freq(struct device *dev, struct device_attribute *attr, > static struct device_attribute devfreq_attrs[] = { > __ATTR(governor, S_IRUGO, show_governor, NULL), > __ATTR(cur_freq, S_IRUGO, show_freq, NULL), > - __ATTR(central_polling, S_IRUGO, show_central_polling, NULL), > __ATTR(polling_interval, S_IRUGO | S_IWUSR, show_polling_interval, > store_polling_interval), > __ATTR(min_freq, S_IRUGO | S_IWUSR, show_min_freq, store_min_freq), > @@ -598,23 +484,6 @@ static struct device_attribute devfreq_attrs[] = { > { }, > }; > > -/** > - * devfreq_start_polling() - Initialize data structure for devfreq framework and > - * start polling registered devfreq devices. > - */ > -static int __init devfreq_start_polling(void) > -{ > - mutex_lock(&devfreq_list_lock); > - polling = false; > - devfreq_wq = create_freezable_workqueue("devfreq_wq"); > - INIT_DEFERRABLE_WORK(&devfreq_work, devfreq_monitor); > - mutex_unlock(&devfreq_list_lock); > - > - devfreq_monitor(&devfreq_work.work); > - return 0; > -} > -late_initcall(devfreq_start_polling); > - > static int __init devfreq_init(void) > { > devfreq_class = class_create(THIS_MODULE, "devfreq"); > @@ -622,7 +491,15 @@ static int __init devfreq_init(void) > pr_err("%s: couldn't create class\n", __FILE__); > return PTR_ERR(devfreq_class); > } > + > + devfreq_wq = create_freezable_workqueue("devfreq_wq"); > + if (IS_ERR(devfreq_wq)) { > + class_destroy(devfreq_class); > + pr_err("%s: couldn't create workqueue\n", __FILE__); > + return PTR_ERR(devfreq_wq); > + } > devfreq_class->dev_attrs = devfreq_attrs; > + > return 0; > } > subsys_initcall(devfreq_init); > @@ -630,6 +507,7 @@ subsys_initcall(devfreq_init); > static void __exit devfreq_exit(void) > { > class_destroy(devfreq_class); > + destroy_workqueue(devfreq_wq); > } > module_exit(devfreq_exit); > > diff --git a/drivers/devfreq/governor.h b/drivers/devfreq/governor.h > index ea7f13c..4a86af7 100644 > --- a/drivers/devfreq/governor.h > +++ b/drivers/devfreq/governor.h > @@ -18,7 +18,16 @@ > > #define to_devfreq(DEV) container_of((DEV), struct devfreq, dev) > > +/* Devfreq events */ > +#define DEVFREQ_GOV_START 0x1 > +#define DEVFREQ_GOV_STOP 0x2 > +#define DEVFREQ_GOV_INTERVAL 0x3 > + > /* Caution: devfreq->lock must be locked before calling update_devfreq */ > extern int update_devfreq(struct devfreq *devfreq); > > +extern int devfreq_monitor_start(struct devfreq *devfreq); > +extern void devfreq_monitor_stop(struct devfreq *devfreq); > +extern int devfreq_monitor_suspend(struct devfreq *devfreq); > +extern int devfreq_monitor_resume(struct devfreq *devfreq); > #endif /* _GOVERNOR_H */ > diff --git a/drivers/devfreq/governor_performance.c b/drivers/devfreq/governor_performance.c > index af75ddd..b657eff 100644 > --- a/drivers/devfreq/governor_performance.c > +++ b/drivers/devfreq/governor_performance.c > @@ -26,14 +26,22 @@ static int devfreq_performance_func(struct devfreq *df, > return 0; > } > > -static int performance_init(struct devfreq *devfreq) > +static int devfreq_performance_handler(struct devfreq *devfreq, > + unsigned int event) > { > - return update_devfreq(devfreq); > + int ret = 0; > + > + if (event == DEVFREQ_GOV_START) { > + mutex_lock(&devfreq->lock); > + ret = update_devfreq(devfreq); > + mutex_unlock(&devfreq->lock); > + } > + > + return ret; > } > > const struct devfreq_governor devfreq_performance = { > .name = "performance", > - .init = performance_init, > .get_target_freq = devfreq_performance_func, > - .no_central_polling = true, > + .event_handler = devfreq_performance_handler, > }; > diff --git a/drivers/devfreq/governor_powersave.c b/drivers/devfreq/governor_powersave.c > index fec0cdb..daa5732 100644 > --- a/drivers/devfreq/governor_powersave.c > +++ b/drivers/devfreq/governor_powersave.c > @@ -23,14 +23,22 @@ static int devfreq_powersave_func(struct devfreq *df, > return 0; > } > > -static int powersave_init(struct devfreq *devfreq) > +static int devfreq_powersave_handler(struct devfreq *devfreq, > + unsigned int event) > { > - return update_devfreq(devfreq); > + int ret = 0; > + > + if (event == DEVFREQ_GOV_START) { > + mutex_lock(&devfreq->lock); > + ret = update_devfreq(devfreq); > + mutex_unlock(&devfreq->lock); > + } > + > + return ret; > } > > const struct devfreq_governor devfreq_powersave = { > .name = "powersave", > - .init = powersave_init, > .get_target_freq = devfreq_powersave_func, > - .no_central_polling = true, > + .event_handler = devfreq_powersave_handler, > }; > diff --git a/drivers/devfreq/governor_simpleondemand.c b/drivers/devfreq/governor_simpleondemand.c > index a2e3eae..9802bf9 100644 > --- a/drivers/devfreq/governor_simpleondemand.c > +++ b/drivers/devfreq/governor_simpleondemand.c > @@ -12,6 +12,7 @@ > #include <linux/errno.h> > #include <linux/devfreq.h> > #include <linux/math64.h> > +#include "governor.h" > > /* Default constants for DevFreq-Simple-Ondemand (DFSO) */ > #define DFSO_UPTHRESHOLD (90) > @@ -88,7 +89,39 @@ static int devfreq_simple_ondemand_func(struct devfreq *df, > return 0; > } > > +int devfreq_simple_ondemand_handler(struct devfreq *devfreq, > + unsigned int event) > +{ > + int ret = 0; > + > + switch (event) { > + case DEVFREQ_GOV_START: > + ret = devfreq_monitor_start(devfreq); > + break; > + > + case DEVFREQ_GOV_STOP: > + devfreq_monitor_stop(devfreq); > + break; > + > + case DEVFREQ_GOV_INTERVAL: > + /* > + * if polling interval is set to zero, stop monitoring. > + * otherwise resume load monitoring. > + */ > + if (!devfreq->profile->polling_ms) > + ret = devfreq_monitor_suspend(devfreq); > + else > + ret = devfreq_monitor_resume(devfreq); > + break; > + default: > + break; > + } > + > + return ret; > +} > + > const struct devfreq_governor devfreq_simple_ondemand = { > .name = "simple_ondemand", > .get_target_freq = devfreq_simple_ondemand_func, > + .event_handler = devfreq_simple_ondemand_handler, > }; > diff --git a/drivers/devfreq/governor_userspace.c b/drivers/devfreq/governor_userspace.c > index 0681246..c48fca0 100644 > --- a/drivers/devfreq/governor_userspace.c > +++ b/drivers/devfreq/governor_userspace.c > @@ -116,10 +116,27 @@ static void userspace_exit(struct devfreq *devfreq) > devfreq->data = NULL; > } > > +int devfreq_userspace_handler(struct devfreq *devfreq, > + unsigned int event) > +{ > + int ret = 0; > + > + switch (event) { > + case DEVFREQ_GOV_START: > + ret = userspace_init(devfreq); > + break; > + case DEVFREQ_GOV_STOP: > + userspace_exit(devfreq); > + break; > + default: > + break; > + } > + > + return ret; > +} > + > const struct devfreq_governor devfreq_userspace = { > .name = "userspace", > .get_target_freq = devfreq_userspace_func, > - .init = userspace_init, > - .exit = userspace_exit, > - .no_central_polling = true, > + .event_handler = devfreq_userspace_handler, > }; > diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h > index 281c72a..7a11c3e 100644 > --- a/include/linux/devfreq.h > +++ b/include/linux/devfreq.h > @@ -91,25 +91,17 @@ struct devfreq_dev_profile { > * status of the device (load = busy_time / total_time). > * If no_central_polling is set, this callback is called > * only with update_devfreq() notified by OPP. > - * @init Called when the devfreq is being attached to a device > - * @exit Called when the devfreq is being removed from a > - * device. Governor should stop any internal routines > - * before return because related data may be > - * freed after exit(). > - * @no_central_polling Do not use devfreq's central polling mechanism. > - * When this is set, devfreq will not call > - * get_target_freq with devfreq_monitor(). However, > - * devfreq will call get_target_freq with > - * devfreq_update() notified by OPP framework. > + * @event_handler Callback for devfreq core framework to notify events > + * to governors. Events include per device governor > + * init and exit, opp changes out of devfreq, suspend > + * and resume of per device devfreq during device idle. > * > * Note that the callbacks are called with devfreq->lock locked by devfreq. > */ > struct devfreq_governor { > const char name[DEVFREQ_NAME_LEN]; > int (*get_target_freq)(struct devfreq *this, unsigned long *freq); > - int (*init)(struct devfreq *this); > - void (*exit)(struct devfreq *this); > - const bool no_central_polling; > + int (*event_handler)(struct devfreq *devfreq, unsigned int event); > }; > > /** > @@ -124,16 +116,10 @@ struct devfreq_governor { > * @nb notifier block used to notify devfreq object that it should > * reevaluate operable frequencies. Devfreq users may use > * devfreq.nb to the corresponding register notifier call chain. > - * @polling_jiffies interval in jiffies. > + * @work delayed work for load monitoring. > * @previous_freq previously configured frequency value. > - * @next_polling the number of remaining jiffies to poll with > - * "devfreq_monitor" executions to reevaluate > - * frequency/voltage of the device. Set by > - * profile's polling_ms interval. > * @data Private data of the governor. The devfreq framework does not > * touch this. > - * @being_removed a flag to mark that this object is being removed in > - * order to prevent trying to remove the object multiple times. > * @min_freq Limit minimum frequency requested by user (0: none) > * @max_freq Limit maximum frequency requested by user (0: none) > * > @@ -153,15 +139,12 @@ struct devfreq { > struct devfreq_dev_profile *profile; > const struct devfreq_governor *governor; > struct notifier_block nb; > + struct delayed_work work; > > - unsigned long polling_jiffies; > unsigned long previous_freq; > - unsigned int next_polling; > > void *data; /* private data for governors */ > > - bool being_removed; > - > unsigned long min_freq; > unsigned long max_freq; > }; > -- > 1.7.11.3 > > > > > > > >

11 years, 8 months

[RFC] sched: nohz_idle_balance

by Vincent Guittot

On tickless system, one CPU runs load balance for all idle CPUs. The cpu_load of this CPU is updated before starting the load balance of each other idle CPUs. We should instead update the cpu_load of the balance_cpu. Signed-off-by: Vincent Guittot <vincent.guittot(a)linaro.org> --- kernel/sched/fair.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 1ca4fe4..9ae3a5b 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4794,14 +4794,15 @@ static void nohz_idle_balance(int this_cpu, enum cpu_idle_type idle) if (need_resched()) break; - raw_spin_lock_irq(&this_rq->lock); - update_rq_clock(this_rq); - update_idle_cpu_load(this_rq); - raw_spin_unlock_irq(&this_rq->lock); + rq = cpu_rq(balance_cpu); + + raw_spin_lock_irq(&rq->lock); + update_rq_clock(rq); + update_idle_cpu_load(rq); + raw_spin_unlock_irq(&rq->lock); rebalance_domains(balance_cpu, CPU_IDLE); - rq = cpu_rq(balance_cpu); if (time_after(this_rq->next_balance, rq->next_balance)) this_rq->next_balance = rq->next_balance; } -- 1.7.9.5

11 years, 8 months

[PATCH v4 0/5] ARM: topology: set the capacity of each cores for big.LITTLE

by Vincent Guittot

This patchset creates an arch_scale_freq_power function for ARM, which is used to set the relative capacity of each core of a big.LITTLE system. It also removes the broken power estimation of x86. Modification since v3: - Add comments - Add optimization for SMP system - Ensure that capacity of a CPU will be at most 1 Modification since v2: - set_power_scale function becomes static - Rework loop in update_siblings_masks - Remove useless code in parse_dt_topology Modification since v1: - Add and update explanation about the use of the table and the range of the value - Remove the use of NR_CPUS and use nr_cpu_ids instead - Remove broken power estimation of x86 Peter Zijlstra (1): sched, x86: Remove broken power estimation Vincent Guittot (4): ARM: topology: Add arch_scale_freq_power function ARM: topology: factorize the update of sibling masks ARM: topology: Update cpu_power according to DT information sched: cpu_power: enable ARCH_POWER arch/arm/kernel/topology.c | 239 ++++++++++++++++++++++++++++++++++++++---- arch/x86/kernel/cpu/Makefile | 2 +- arch/x86/kernel/cpu/sched.c | 55 ---------- kernel/sched/features.h | 2 +- 4 files changed, 219 insertions(+), 79 deletions(-) delete mode 100644 arch/x86/kernel/cpu/sched.c -- 1.7.9.5

11 years, 8 months

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linaro-dev September 2012