greybus: tracing: define interface traces

Define a new gb_module trace point event class, used to trace events
associated with the interface abstraction.  Define four basic trace
points for this--creation time, drop of last reference, before
registring interfaces and after de-registering them.  In addition,
define traces for activating and deactivating, and enabling and
disabling an interface.

Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

drivers/staging/greybus/greybus_trace.h

@@ -209,6 +209,86 @@ DEFINE_MODULE_EVENT(gb_module_del);
 
 #undef DEFINE_MODULE_EVENT
 
+DECLARE_EVENT_CLASS(gb_interface,
+
+	TP_PROTO(struct gb_interface *intf),
+
+	TP_ARGS(intf),
+
+	TP_STRUCT__entry(
+		__field(u8, id)		/* Interface id */
+		__field(u8, module_id)
+		__field(u8, device_id)
+		__field(bool, disconnected)
+		__field(bool, ejected)
+		__field(bool, active)
+		__field(bool, enabled)
+	),
+
+	TP_fast_assign(
+		__entry->id = intf->interface_id;
+		__entry->module_id = intf->module->module_id;
+		__entry->device_id = intf->device_id;
+		__entry->disconnected = intf->disconnected;
+		__entry->ejected = intf->ejected;
+		__entry->active = intf->active;
+		__entry->enabled = intf->enabled;
+	),
+
+	TP_printk("greybus: intf_id=%hhu device_id=%hhu module_id=%hhu D=%u J=%u A=%u E=%u",
+		__entry->id, __entry->device_id, __entry->module_id,
+		__entry->disconnected, __entry->ejected, __entry->active,
+		__entry->enabled)
+);
+
+#define DEFINE_INTERFACE_EVENT(name)					\
+		DEFINE_EVENT(gb_interface, name,			\
+				TP_PROTO(struct gb_interface *intf),	\
+				TP_ARGS(intf))
+
+/*
+ * Occurs after a new interface is successfully created.
+ */
+DEFINE_INTERFACE_EVENT(gb_interface_create);
+
+/*
+ * Occurs after the last reference to an interface has been dropped.
+ */
+DEFINE_INTERFACE_EVENT(gb_interface_release);
+
+/*
+ * Occurs after an interface been registerd.
+ */
+DEFINE_INTERFACE_EVENT(gb_interface_add);
+
+/*
+ * Occurs when a registered interface gets deregisterd.
+ */
+DEFINE_INTERFACE_EVENT(gb_interface_del);
+
+/*
+ * Occurs when a registered interface has been successfully
+ * activated.
+ */
+DEFINE_INTERFACE_EVENT(gb_interface_activate);
+
+/*
+ * Occurs when an activated interface is being deactivated.
+ */
+DEFINE_INTERFACE_EVENT(gb_interface_deactivate);
+
+/*
+ * Occurs when an interface has been successfully enabled.
+ */
+DEFINE_INTERFACE_EVENT(gb_interface_enable);
+
+/*
+ * Occurs when an enabled interface is being disabled.
+ */
+DEFINE_INTERFACE_EVENT(gb_interface_disable);
+
+#undef DEFINE_INTERFACE_EVENT
+
 DECLARE_EVENT_CLASS(gb_host_device,
 
 	TP_PROTO(struct gb_host_device *hd),

drivers/staging/greybus/interface.c

@@ -9,6 +9,7 @@
 
 #include "greybus.h"
 
+#include "greybus_trace.h"
 
 #define GB_INTERFACE_DEVICE_ID_BAD	0xff
 
@@ -326,6 +327,8 @@ static void gb_interface_release(struct device *dev)
 {
 	struct gb_interface *intf = to_gb_interface(dev);
 
+	trace_gb_interface_release(intf);
+
 	kfree(intf);
 }
 
@@ -375,6 +378,8 @@ struct gb_interface *gb_interface_create(struct gb_module *module,
 	dev_set_name(&intf->dev, "%s.%u", dev_name(&module->dev),
 			interface_id);
 
+	trace_gb_interface_create(intf);
+
 	return intf;
 }
 
@@ -506,6 +511,8 @@ int gb_interface_activate(struct gb_interface *intf)
 
 	intf->active = true;
 
+	trace_gb_interface_activate(intf);
+
 	return 0;
 
 err_hibernate_link:
@@ -530,6 +537,8 @@ void gb_interface_deactivate(struct gb_interface *intf)
 	if (!intf->active)
 		return;
 
+	trace_gb_interface_deactivate(intf);
+
 	gb_interface_route_destroy(intf);
 	gb_interface_hibernate_link(intf);
 	gb_interface_unipro_set(intf, false);
@@ -629,6 +638,8 @@ int gb_interface_enable(struct gb_interface *intf)
 
 	intf->enabled = true;
 
+	trace_gb_interface_enable(intf);
+
 	return 0;
 
 err_destroy_bundles:
@@ -658,6 +669,8 @@ void gb_interface_disable(struct gb_interface *intf)
 	if (!intf->enabled)
 		return;
 
+	trace_gb_interface_disable(intf);
+
 	/*
 	 * Disable the control-connection early to avoid operation timeouts
 	 * when the interface is already gone.
@@ -687,6 +700,8 @@ int gb_interface_add(struct gb_interface *intf)
 		return ret;
 	}
 
+	trace_gb_interface_add(intf);
+
 	dev_info(&intf->dev, "Interface added: VID=0x%08x, PID=0x%08x\n",
 		 intf->vendor_id, intf->product_id);
 	dev_info(&intf->dev, "DDBL1 Manufacturer=0x%08x, Product=0x%08x\n",
@@ -699,6 +714,8 @@ int gb_interface_add(struct gb_interface *intf)
 void gb_interface_del(struct gb_interface *intf)
 {
 	if (device_is_registered(&intf->dev)) {
+		trace_gb_interface_del(intf);
+
 		device_del(&intf->dev);
 		dev_info(&intf->dev, "Interface removed\n");
 	}