From e8bca479c3f269ebb3a3acea5ef63314bb677060 Mon Sep 17 00:00:00 2001 From: Todd E Brandt Date: Tue, 10 Jun 2014 07:31:22 -0700 Subject: 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: Todd Brandt Signed-off-by: Rafael J. Wysocki --- drivers/base/power/main.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index de3fe4fe350a..bf412961a934 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -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); -- cgit v1.2.3