PM / QoS: Add dev_pm_qos_request tracepoints

Adds tracepoints to dev_pm_qos_add_request, dev_pm_qos_update_request,
and dev_pm_qos_remove_request.  It's useful for checking device name,
dev_pm_qos_request_type, and value.

Signed-off-by: Sahara <keun-o.park@windriver.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/base/power/qos.c b/drivers/base/power/qos.c
index 71671c4..5c1361a 100644
--- a/drivers/base/power/qos.c
+++ b/drivers/base/power/qos.c
@@ -42,6 +42,7 @@
 #include <linux/export.h>
 #include <linux/pm_runtime.h>
 #include <linux/err.h>
+#include <trace/events/power.h>
 
 #include "power.h"
 
@@ -305,6 +306,7 @@
 	else if (!dev->power.qos)
 		ret = dev_pm_qos_constraints_allocate(dev);
 
+	trace_dev_pm_qos_add_request(dev_name(dev), type, value);
 	if (!ret) {
 		req->dev = dev;
 		req->type = type;
@@ -349,6 +351,8 @@
 		return -EINVAL;
 	}
 
+	trace_dev_pm_qos_update_request(dev_name(req->dev), req->type,
+					new_value);
 	if (curr_value != new_value)
 		ret = apply_constraint(req, PM_QOS_UPDATE_REQ, new_value);
 
@@ -398,6 +402,8 @@
 	if (IS_ERR_OR_NULL(req->dev->power.qos))
 		return -ENODEV;
 
+	trace_dev_pm_qos_remove_request(dev_name(req->dev), req->type,
+					PM_QOS_DEFAULT_VALUE);
 	ret = apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE);
 	memset(req, 0, sizeof(*req));
 	return ret;