From 536446772f1181f3afdf332780b5325d1b6980c6 Mon Sep 17 00:00:00 2001 From: Shuah Khan Date: Fri, 26 Jul 2013 13:30:20 -0600 Subject: PM / Sleep: new trace event to print device suspend and resume times A new trace event is added to PM events to print the time it takes to suspend and resume a device. It generates trace messages that include device, driver, parent information in addition to the type of PM ops invoked as well as the PM event and error status from the PM ops. Example trace below: bash-2239 [000] .... 290.883035: device_pm_report_time: backlight acpi_video0 parent=0000:00:02.0 state=freeze ops=class nsecs=332 err=0 bash-2239 [000] .... 290.883041: device_pm_report_time: rfkill rf kill3 parent=phy0 state=freeze ops=legacy class nsecs=216 err=0 bash-2239 [001] .... 290.973892: device_pm_report_time: ieee80211 phy0 parent=0000:01:00.0 state=freeze ops=legacy class nsecs=90846477 err=0 bash-2239 [001] .... 293.660129: device_pm_report_time: ieee80211 phy0 parent=0000:01:00.0 state=restore ops=legacy class nsecs=101295162 err=0 bash-2239 [001] .... 293.660147: device_pm_report_time: rfkill rfkill3 parent=phy0 state=restore ops=legacy class nsecs=1804 err=0 bash-2239 [001] .... 293.660157: device_pm_report_time: backlight acpi_video0 parent=0000:00:02.0 state=restore ops=class nsecs=757 err=0 Signed-off-by: Shuah Khan Signed-off-by: Rafael J. Wysocki --- drivers/base/power/main.c | 77 ++++++++++++++++++++++++++--------------------- 1 file changed, 43 insertions(+), 34 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 5a9b6569dd74..9f098a82cf04 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -28,6 +28,7 @@ #include #include #include +#include #include #include "../base.h" #include "power.h" @@ -56,6 +57,30 @@ static pm_message_t pm_transition; static int async_error; +static char *pm_verb(int event) +{ + switch (event) { + case PM_EVENT_SUSPEND: + return "suspend"; + case PM_EVENT_RESUME: + return "resume"; + case PM_EVENT_FREEZE: + return "freeze"; + case PM_EVENT_QUIESCE: + return "quiesce"; + case PM_EVENT_HIBERNATE: + return "hibernate"; + case PM_EVENT_THAW: + return "thaw"; + case PM_EVENT_RESTORE: + return "restore"; + case PM_EVENT_RECOVER: + return "recover"; + default: + return "(unknown PM event)"; + } +} + /** * device_pm_sleep_init - Initialize system suspend-related device fields. * @dev: Device object being initialized. @@ -172,16 +197,21 @@ static ktime_t initcall_debug_start(struct device *dev) } static void initcall_debug_report(struct device *dev, ktime_t calltime, - int error) + int error, pm_message_t state, char *info) { - ktime_t delta, rettime; + ktime_t rettime; + s64 nsecs; + + rettime = ktime_get(); + nsecs = (s64) ktime_to_ns(ktime_sub(rettime, calltime)); if (pm_print_times_enabled) { - rettime = ktime_get(); - delta = ktime_sub(rettime, calltime); pr_info("call %s+ returned %d after %Ld usecs\n", dev_name(dev), - error, (unsigned long long)ktime_to_ns(delta) >> 10); + error, (unsigned long long)nsecs >> 10); } + + trace_device_pm_report_time(dev, info, nsecs, pm_verb(state.event), + error); } /** @@ -309,30 +339,6 @@ static pm_callback_t pm_noirq_op(const struct dev_pm_ops *ops, pm_message_t stat return NULL; } -static char *pm_verb(int event) -{ - switch (event) { - case PM_EVENT_SUSPEND: - return "suspend"; - case PM_EVENT_RESUME: - return "resume"; - case PM_EVENT_FREEZE: - return "freeze"; - case PM_EVENT_QUIESCE: - return "quiesce"; - case PM_EVENT_HIBERNATE: - return "hibernate"; - case PM_EVENT_THAW: - return "thaw"; - case PM_EVENT_RESTORE: - return "restore"; - case PM_EVENT_RECOVER: - return "recover"; - default: - return "(unknown PM event)"; - } -} - static void pm_dev_dbg(struct device *dev, pm_message_t state, char *info) { dev_dbg(dev, "%s%s%s\n", info, pm_verb(state.event), @@ -379,7 +385,7 @@ static int dpm_run_callback(pm_callback_t cb, struct device *dev, error = cb(dev); suspend_report_result(cb, error); - initcall_debug_report(dev, calltime, error); + initcall_debug_report(dev, calltime, error, state, info); return error; } @@ -1027,7 +1033,8 @@ EXPORT_SYMBOL_GPL(dpm_suspend_end); * @cb: Suspend callback to execute. */ static int legacy_suspend(struct device *dev, pm_message_t state, - int (*cb)(struct device *dev, pm_message_t state)) + int (*cb)(struct device *dev, pm_message_t state), + char *info) { int error; ktime_t calltime; @@ -1037,7 +1044,7 @@ static int legacy_suspend(struct device *dev, pm_message_t state, error = cb(dev, state); suspend_report_result(cb, error); - initcall_debug_report(dev, calltime, error); + initcall_debug_report(dev, calltime, error, state, info); return error; } @@ -1097,7 +1104,8 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async) goto Run; } else if (dev->class->suspend) { pm_dev_dbg(dev, state, "legacy class "); - error = legacy_suspend(dev, state, dev->class->suspend); + error = legacy_suspend(dev, state, dev->class->suspend, + "legacy class "); goto End; } } @@ -1108,7 +1116,8 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async) callback = pm_op(dev->bus->pm, state); } else if (dev->bus->suspend) { pm_dev_dbg(dev, state, "legacy bus "); - error = legacy_suspend(dev, state, dev->bus->suspend); + error = legacy_suspend(dev, state, dev->bus->suspend, + "legacy bus "); goto End; } } -- cgit v1.2.3-55-g7522 From b071f2b21acf27c2fddd36aa193e015033b9c357 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Sun, 4 Aug 2013 01:23:41 +0200 Subject: PM / OPP: Export opp_add() Export opp_add() so that modules can use it. Signed-off-by: Viresh Kumar Acked-by: Nishanth Menon Signed-off-by: Rafael J. Wysocki --- drivers/base/power/opp.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/base') diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index c8ec186303db..ef89897c6043 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -460,6 +460,7 @@ int opp_add(struct device *dev, unsigned long freq, unsigned long u_volt) srcu_notifier_call_chain(&dev_opp->head, OPP_EVENT_ADD, new_opp); return 0; } +EXPORT_SYMBOL_GPL(opp_add); /** * opp_set_availability() - helper to set the availability of an opp -- cgit v1.2.3-55-g7522 From f86e4718f24b83be0c42894d2b97accc993d65d3 Mon Sep 17 00:00:00 2001 From: Sudeep KarkadaNagesha Date: Mon, 17 Jun 2013 12:58:45 +0100 Subject: driver/core: cpu: initialize of_node in cpu's device struture CPUs are also registered as devices but the of_node in these cpu devices are not initialized. Currently different drivers requiring to access cpu device node are parsing the nodes themselves and initialising the of_node in cpu device. The of_node in all the cpu devices needs to be initialized properly and at one place. The best place to update this is CPU subsystem driver when registering the cpu devices. The OF/DT core library now provides of_get_cpu_node to retrieve a cpu device node for a given logical index by abstracting the architecture specific details. This patch uses of_get_cpu_node to assign of_node when registering the cpu devices. Acked-by: Greg Kroah-Hartman Acked-by: Rob Herring Signed-off-by: Sudeep KarkadaNagesha --- drivers/base/cpu.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/base') diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index 4c358bc44c72..4cf071764be3 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -14,6 +14,7 @@ #include #include #include +#include #include "base.h" @@ -289,6 +290,7 @@ int register_cpu(struct cpu *cpu, int num) cpu->dev.release = cpu_device_release; cpu->dev.offline_disabled = !cpu->hotpluggable; cpu->dev.offline = !cpu_online(num); + cpu->dev.of_node = of_get_cpu_node(num, NULL); #ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE cpu->dev.bus->uevent = arch_cpu_uevent; #endif -- cgit v1.2.3-55-g7522 From 5e33bc4165f3edd558d9633002465a95230effc1 Mon Sep 17 00:00:00 2001 From: Rafael J. Wysocki Date: Wed, 28 Aug 2013 21:41:01 +0200 Subject: driver core / ACPI: Avoid device hot remove locking issues device_hotplug_lock is held around the acpi_bus_trim() call in acpi_scan_hot_remove() which generally removes devices (it removes ACPI device objects at least, but it may also remove "physical" device objects through .detach() callbacks of ACPI scan handlers). Thus, potentially, device sysfs attributes are removed under that lock and to remove those attributes it is necessary to hold the s_active references of their directory entries for writing. On the other hand, the execution of a .show() or .store() callback from a sysfs attribute is carried out with that attribute's s_active reference held for reading. Consequently, if any device sysfs attribute that may be removed from within acpi_scan_hot_remove() through acpi_bus_trim() has a .store() or .show() callback which acquires device_hotplug_lock, the execution of that callback may deadlock with the removal of the attribute. [Unfortunately, the "online" device attribute of CPUs and memory blocks is one of them.] To avoid such deadlocks, make all of the sysfs attribute callbacks that need to lock device hotplug, for example store_online(), use a special function, lock_device_hotplug_sysfs(), to lock device hotplug and return the result of that function immediately if it is not zero. This will cause the s_active reference of the directory entry in question to be released and the syscall to be restarted if device_hotplug_lock cannot be acquired. [show_online() actually doesn't need to lock device hotplug, but it is useful to serialize it with respect to device_offline() and device_online() for the same device (in case user space attempts to run them concurrently) which can be done with the help of device_lock().] Reported-by: Yasuaki Ishimatsu Reported-and-tested-by: Gu Zheng Suggested-by: Tejun Heo Signed-off-by: Rafael J. Wysocki Acked-by: Greg Kroah-Hartman Acked-by: Toshi Kani --- drivers/base/core.c | 43 ++++++++++++++++++++++++++++--------------- drivers/base/memory.c | 4 +++- include/linux/device.h | 1 + 3 files changed, 32 insertions(+), 16 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/core.c b/drivers/base/core.c index 8856d74545d9..ac419a15fcd4 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -49,6 +49,28 @@ static struct kobject *dev_kobj; struct kobject *sysfs_dev_char_kobj; struct kobject *sysfs_dev_block_kobj; +static DEFINE_MUTEX(device_hotplug_lock); + +void lock_device_hotplug(void) +{ + mutex_lock(&device_hotplug_lock); +} + +void unlock_device_hotplug(void) +{ + mutex_unlock(&device_hotplug_lock); +} + +int lock_device_hotplug_sysfs(void) +{ + if (mutex_trylock(&device_hotplug_lock)) + return 0; + + /* Avoid busy looping (5 ms of sleep should do). */ + msleep(5); + return restart_syscall(); +} + #ifdef CONFIG_BLOCK static inline int device_is_not_partition(struct device *dev) { @@ -408,9 +430,9 @@ static ssize_t show_online(struct device *dev, struct device_attribute *attr, { bool val; - lock_device_hotplug(); + device_lock(dev); val = !dev->offline; - unlock_device_hotplug(); + device_unlock(dev); return sprintf(buf, "%u\n", val); } @@ -424,7 +446,10 @@ static ssize_t store_online(struct device *dev, struct device_attribute *attr, if (ret < 0) return ret; - lock_device_hotplug(); + ret = lock_device_hotplug_sysfs(); + if (ret) + return ret; + ret = val ? device_online(dev) : device_offline(dev); unlock_device_hotplug(); return ret < 0 ? ret : count; @@ -1479,18 +1504,6 @@ EXPORT_SYMBOL_GPL(put_device); EXPORT_SYMBOL_GPL(device_create_file); EXPORT_SYMBOL_GPL(device_remove_file); -static DEFINE_MUTEX(device_hotplug_lock); - -void lock_device_hotplug(void) -{ - mutex_lock(&device_hotplug_lock); -} - -void unlock_device_hotplug(void) -{ - mutex_unlock(&device_hotplug_lock); -} - static int device_check_offline(struct device *dev, void *not_used) { int ret; diff --git a/drivers/base/memory.c b/drivers/base/memory.c index 2b7813ec6d02..6f4c99ff1ce7 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -351,7 +351,9 @@ store_mem_state(struct device *dev, mem = container_of(dev, struct memory_block, dev); - lock_device_hotplug(); + ret = lock_device_hotplug_sysfs(); + if (ret) + return ret; if (!strncmp(buf, "online_kernel", min_t(int, count, 13))) { offline = false; diff --git a/include/linux/device.h b/include/linux/device.h index 22b546a58591..545a04285120 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -895,6 +895,7 @@ static inline bool device_supports_offline(struct device *dev) extern void lock_device_hotplug(void); extern void unlock_device_hotplug(void); +extern int lock_device_hotplug_sysfs(void); extern int device_offline(struct device *dev); extern int device_online(struct device *dev); /* -- cgit v1.2.3-55-g7522