Commit e8bca479 authored by Todd E Brandt's avatar Todd E Brandt Committed by Rafael J. Wysocki
Browse files

PM / sleep: trace events for device PM callbacks 



Adds two trace events which supply the same info that initcall_debug
provides, but via ftrace instead of dmesg. The existing initcall_debug
calls require the pm_print_times_enabled var to be set (either via
sysfs or via the kernel cmd line). The new trace events provide all the
same info as the initcall_debug prints but with less overhead, and also
with coverage of device prepare and complete device callbacks.

These events replace the device_pm_report_time event (which has been
removed). device_pm_callback_start is called first and provides the device
and callback info. device_pm_callback_end is called after with the
device name and error info. The time and pid are gathered from the trace
data headers.

Signed-off-by: default avatarTodd Brandt <todd.e.brandt@intel.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent bb3632c6

drivers/base/power/main.c

+10 −4
Original line number Diff line number Diff line
@@ -214,9 +214,6 @@ static void initcall_debug_report(struct device *dev, ktime_t calltime, 
		pr_info("call %s+ returned %d after %Ld usecs\n", dev_name(dev),

			error, (unsigned long long)nsecs >> 10);

	}



	trace_device_pm_report_time(dev, info, nsecs, pm_verb(state.event),

				    error);

}



/**
@@ -387,7 +384,9 @@ static int dpm_run_callback(pm_callback_t cb, struct device *dev, 
	calltime = initcall_debug_start(dev);



	pm_dev_dbg(dev, state, info);

	trace_device_pm_callback_start(dev, info, state.event);

	error = cb(dev);

	trace_device_pm_callback_end(dev, error);

	suspend_report_result(cb, error);



	initcall_debug_report(dev, calltime, error, state, info);
@@ -919,7 +918,9 @@ static void device_complete(struct device *dev, pm_message_t state) 


	if (callback) {

		pm_dev_dbg(dev, state, info);

		trace_device_pm_callback_start(dev, info, state.event);

		callback(dev);

		trace_device_pm_callback_end(dev, 0);

	}



	device_unlock(dev);
@@ -1307,7 +1308,9 @@ static int legacy_suspend(struct device *dev, pm_message_t state, 


	calltime = initcall_debug_start(dev);



	trace_device_pm_callback_start(dev, info, state.event);

	error = cb(dev, state);

	trace_device_pm_callback_end(dev, error);

	suspend_report_result(cb, error);



	initcall_debug_report(dev, calltime, error, state, info);
@@ -1563,8 +1566,11 @@ static int device_prepare(struct device *dev, pm_message_t state) 
		callback = dev->driver->pm->prepare;

	}



	if (callback)

	if (callback) {

		trace_device_pm_callback_start(dev, info, state.event);

		ret = callback(dev);

		trace_device_pm_callback_end(dev, ret);

	}



	device_unlock(dev);

include/trace/events/power.h

+42 −18
Original line number Diff line number Diff line
@@ -93,6 +93,17 @@ TRACE_EVENT(pstate_sample, 
#define PWR_EVENT_EXIT -1

#endif



#define pm_verb_symbolic(event) \

	__print_symbolic(event, \

		{ PM_EVENT_SUSPEND, "suspend" }, \

		{ PM_EVENT_RESUME, "resume" }, \

		{ PM_EVENT_FREEZE, "freeze" }, \

		{ PM_EVENT_QUIESCE, "quiesce" }, \

		{ PM_EVENT_HIBERNATE, "hibernate" }, \

		{ PM_EVENT_THAW, "thaw" }, \

		{ PM_EVENT_RESTORE, "restore" }, \

		{ PM_EVENT_RECOVER, "recover" })



DEFINE_EVENT(cpu, cpu_frequency,



	TP_PROTO(unsigned int frequency, unsigned int cpu_id),
@@ -100,41 +111,54 @@ DEFINE_EVENT(cpu, cpu_frequency, 
	TP_ARGS(frequency, cpu_id)

);



TRACE_EVENT(device_pm_report_time,

TRACE_EVENT(device_pm_callback_start,



	TP_PROTO(struct device *dev, const char *pm_ops, s64 ops_time,

		 char *pm_event_str, int error),

	TP_PROTO(struct device *dev, const char *pm_ops, int event),



	TP_ARGS(dev, pm_ops, ops_time, pm_event_str, error),

	TP_ARGS(dev, pm_ops, event),



	TP_STRUCT__entry(

		__string(device, dev_name(dev))

		__string(driver, dev_driver_string(dev))

		__string(parent, dev->parent ? dev_name(dev->parent) : "none")

		__string(pm_ops, pm_ops ? pm_ops : "none ")

		__string(pm_event_str, pm_event_str)

		__field(s64, ops_time)

		__field(int, error)

		__field(int, event)

	),



	TP_fast_assign(

		const char *tmp = dev->parent ? dev_name(dev->parent) : "none";

		const char *tmp_i = pm_ops ? pm_ops : "none ";

		__assign_str(device, dev_name(dev));

		__assign_str(driver, dev_driver_string(dev));

		__assign_str(parent,

			dev->parent ? dev_name(dev->parent) : "none");

		__assign_str(pm_ops, pm_ops ? pm_ops : "none ");

		__entry->event = event;

	),



	TP_printk("%s %s, parent: %s, %s[%s]", __get_str(driver),

		__get_str(device), __get_str(parent), __get_str(pm_ops),

		pm_verb_symbolic(__entry->event))

);



TRACE_EVENT(device_pm_callback_end,



	TP_PROTO(struct device *dev, int error),



	TP_ARGS(dev, error),



	TP_STRUCT__entry(

		__string(device, dev_name(dev))

		__string(driver, dev_driver_string(dev))

		__field(int, error)

	),



	TP_fast_assign(

		__assign_str(device, dev_name(dev));

		__assign_str(driver, dev_driver_string(dev));

		__assign_str(parent, tmp);

		__assign_str(pm_ops, tmp_i);

		__assign_str(pm_event_str, pm_event_str);

		__entry->ops_time = ops_time;

		__entry->error = error;

	),



	/* ops_str has an extra space at the end */

	TP_printk("%s %s parent=%s state=%s ops=%snsecs=%lld err=%d",

		__get_str(driver), __get_str(device), __get_str(parent),

		__get_str(pm_event_str), __get_str(pm_ops),

		__entry->ops_time, __entry->error)

	TP_printk("%s %s, err=%d",

		__get_str(driver), __get_str(device), __entry->error)

);



TRACE_EVENT(suspend_resume,

CRA Git | Maintained and supported by SUSTech CRA and CCSE