Added event tracing for device_resume. This helps quickly pinpoint which
devices take a long time to resume.
Signed-off-by: Sameer Nanda <snanda@xxxxxxxxxxxx>
---
Documentation/trace/events-power.txt | 20 +++++++++++
drivers/base/power/main.c | 10 ++++++
include/trace/events/power.h | 59 ++++++++++++++++++++++++++++++++++
3 files changed, 89 insertions(+), 0 deletions(-)
diff --git a/Documentation/trace/events-power.txt b/Documentation/trace/events-power.txt
index cf794af..dbfb7f0 100644
--- a/Documentation/trace/events-power.txt
+++ b/Documentation/trace/events-power.txt
@@ -88,3 +88,23 @@ power_domain_target "%s state=%lu cpu_id=%lu"
The first parameter gives the power domain name (e.g. "mpu_pwrdm").
The second parameter is the power domain target state.
+4. Device resume events
+=======================
+The device resume events are used for measuring the time taken to resume
+devices.
+
+device_resume_in "device=%s driver=%s"
+device_resume_waited "device=%s driver=%s time_delta=%lld"
+device_resume_out "device=%s driver=%s time_delta=%lld"
+
+The first parameter is the device that is being resumed.
+
+The second parameter is the driver associated with the device being resumed.
+
+The third parameter in device_resume_waited is the time delta from the entry
+point of device_resume to the wait completion of parent device being resumed.
+The unit for time_delta is us.
+
+The third parameter in device_resume_out is the time delta from the wait
+completion of parent device being resumed to device_resume being completed.
+The unit for time_delta is us.
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index b462c0e..3ed01cd 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -28,6 +28,7 @@
#include <linux/sched.h>
#include <linux/async.h>
#include <linux/suspend.h>
+#include <trace/events/power.h>
#include "../base.h"
#include "power.h"
@@ -565,11 +566,19 @@ static int device_resume(struct device *dev, pm_message_t state, bool async)
char *info = NULL;
int error = 0;
bool put = false;
+ s64 in_time = ktime_to_us(ktime_get());
+ s64 wait_done_time;
+
+ trace_device_resume_in(dev);
TRACE_DEVICE(dev);
TRACE_RESUME(0);
dpm_wait(dev->parent, async);
+
+ wait_done_time = ktime_to_us(ktime_get());
+ trace_device_resume_waited(dev, wait_done_time - in_time);
+
device_lock(dev);
/*
@@ -638,6 +647,7 @@ static int device_resume(struct device *dev, pm_message_t state, bool async)
if (put)
pm_runtime_put_sync(dev);
+ trace_device_resume_out(dev, ktime_to_us(ktime_get()) - wait_done_time);
return error;
}
diff --git a/include/trace/events/power.h b/include/trace/events/power.h
index cae9a94..9601419 100644
--- a/include/trace/events/power.h
+++ b/include/trace/events/power.h
@@ -4,6 +4,7 @@
#if !defined(_TRACE_POWER_H) || defined(TRACE_HEADER_MULTI_READ)
#define _TRACE_POWER_H
+#include <linux/device.h>
#include <linux/ktime.h>
#include <linux/tracepoint.h>
@@ -48,6 +49,64 @@ DEFINE_EVENT(cpu, cpu_frequency,
TP_ARGS(frequency, cpu_id)
);
+#define get_driver_name(dev) dev->driver && dev->driver->name ? \
+ dev->driver->name : ""
+
+TRACE_EVENT(device_resume_in,
+
+ TP_PROTO(struct device *dev),
+
+ TP_ARGS(dev),
+
+ TP_STRUCT__entry(
+ __string( device_name, dev_name(dev) )
+ __string( driver_name, get_driver_name(dev) )
+ ),
+
+ TP_fast_assign(
+ __assign_str(device_name, dev_name(dev));
+ __assign_str(driver_name, get_driver_name(dev));
+ ),
+
+ TP_printk("device=%s driver=%s", __get_str(device_name), __get_str(driver_name))
+);
+
+DECLARE_EVENT_CLASS(device_resume_internal,
+
+ TP_PROTO(struct device *dev, s64 time_delta),
+
+ TP_ARGS(dev, time_delta),
+
+ TP_STRUCT__entry(
+ __field( s64, time_delta )
+ __string( device_name, dev_name(dev) )
+ __string( driver_name, get_driver_name(dev) )
+ ),
+
+ TP_fast_assign(
+ __entry->time_delta = time_delta;
+ __assign_str(device_name, dev_name(dev));
+ __assign_str(driver_name, get_driver_name(dev));
+ ),
+
+ TP_printk("device=%s driver=%s time_delta=%lld", __get_str(device_name),
+ __get_str(driver_name), __entry->time_delta)
+);
+
+DEFINE_EVENT(device_resume_internal, device_resume_waited,
+
+ TP_PROTO(struct device *dev, s64 time_delta),
+
+ TP_ARGS(dev, time_delta)
+);
+
+DEFINE_EVENT(device_resume_internal, device_resume_out,
+
+ TP_PROTO(struct device *dev, s64 time_delta),
+
+ TP_ARGS(dev, time_delta)
+);
+
TRACE_EVENT(machine_suspend,
TP_PROTO(unsigned int state),
--
1.7.7.3
--
To unsubscribe from this list: send the line "unsubscribe linux-doc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
