greybus: tracing: define connection traces

Define a new gb_connection trace point event class, used to trace
events associated with the connection abstraction.  Define four basic
trace events for this--creation, drop of last reference, and when
adding or dropping any other reference.  There are certainly
more events that we might want to add, but aim is to just get the
basic framework in place.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

1 files changed, 21 insertions, 0 deletions

diff --git a/drivers/staging/greybus/connection.c b/drivers/staging/greybus/connection.c
index 3be767b9a0de..d35e95a17c56 100644
--- a/drivers/staging/greybus/connection.c
+++ b/drivers/staging/greybus/connection.c
@@ -10,6 +10,7 @@
 #include <linux/workqueue.h>
 
 #include "greybus.h"
+#include "greybus_trace.h"
 
 
 static void gb_connection_kref_release(struct kref *kref);
@@ -38,10 +39,14 @@ gb_connection_intf_find(struct gb_interface *intf, u16 cport_id)
 static void gb_connection_get(struct gb_connection *connection)
 {
 	kref_get(&connection->kref);
+
+	trace_gb_connection_get(connection);
 }
 
 static void gb_connection_put(struct gb_connection *connection)
 {
+	trace_gb_connection_put(connection);
+
 	kref_put(&connection->kref, gb_connection_kref_release);
 }
 
@@ -93,6 +98,8 @@ static void gb_connection_kref_release(struct kref *kref)
 
 	connection = container_of(kref, struct gb_connection, kref);
 
+	trace_gb_connection_release(connection);
+
 	kfree(connection);
 }
 
@@ -204,6 +211,8 @@ _gb_connection_create(struct gb_host_device *hd, int hd_cport_id,
 
 	mutex_unlock(&gb_connection_mutex);
 
+	trace_gb_connection_create(connection);
+
 	return connection;
 
 err_free_connection:
@@ -709,6 +718,9 @@ int gb_connection_enable(struct gb_connection *connection)
 		goto out_unlock;
 
 	ret = _gb_connection_enable(connection, true);
+	if (!ret)
+		trace_gb_connection_enable(connection);
+
 out_unlock:
 	mutex_unlock(&connection->mutex);
 
@@ -731,6 +743,9 @@ int gb_connection_enable_tx(struct gb_connection *connection)
 		goto out_unlock;
 
 	ret = _gb_connection_enable(connection, false);
+	if (!ret)
+		trace_gb_connection_enable(connection);
+
 out_unlock:
 	mutex_unlock(&connection->mutex);
 
@@ -751,6 +766,8 @@ void gb_connection_disable_rx(struct gb_connection *connection)
 	gb_connection_flush_incoming_operations(connection, -ESHUTDOWN);
 	spin_unlock_irq(&connection->lock);
 
+	trace_gb_connection_disable(connection);
+
 out_unlock:
 	mutex_unlock(&connection->mutex);
 }
@@ -793,6 +810,8 @@ void gb_connection_disable(struct gb_connection *connection)
 
 	connection->state = GB_CONNECTION_STATE_DISABLED;
 
+	trace_gb_connection_disable(connection);
+
 	/* control-connection tear down is deferred when mode switching */
 	if (!connection->mode_switch) {
 		gb_connection_svc_connection_destroy(connection);
@@ -822,6 +841,8 @@ void gb_connection_disable_forced(struct gb_connection *connection)
 	gb_connection_svc_connection_destroy(connection);
 	gb_connection_hd_cport_disable(connection);
 
+	trace_gb_connection_disable(connection);
+
 out_unlock:
 	mutex_unlock(&connection->mutex);
 }