[PATCH V4 2/3] usb: gadget: configfs: add function link trace entry

[Linyu Yuan <quic_linyyuan@quicinc.com>]

add trace in function config_usb_cfg_link()
will show which function was added to gadget configuration.

Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
---
 drivers/usb/gadget/configfs.c       |  4 ++++
 drivers/usb/gadget/configfs_trace.h | 17 +++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/drivers/usb/gadget/configfs.c b/drivers/usb/gadget/configfs.c
index f7f3af8..8c64640 100644
--- a/drivers/usb/gadget/configfs.c
+++ b/drivers/usb/gadget/configfs.c
@@ -426,6 +426,10 @@ static int config_usb_cfg_link(
 	struct usb_function *f;
 	int ret;
 
+	trace_config_usb_cfg_link(config_item_name(&gi->group.cg_item),
+				config_item_name(usb_cfg_ci),
+				config_item_name(usb_func_ci));
+
 	mutex_lock(&gi->lock);
 	/*
 	 * Make sure this function is from within our _this_ gadget and not
diff --git a/drivers/usb/gadget/configfs_trace.h b/drivers/usb/gadget/configfs_trace.h
index f2e17e4..5c666f1 100644
--- a/drivers/usb/gadget/configfs_trace.h
+++ b/drivers/usb/gadget/configfs_trace.h
@@ -26,6 +26,23 @@ TRACE_EVENT(gadget_dev_desc_UDC_store,
 		__get_str(udc_name))
 );
 
+TRACE_EVENT(config_usb_cfg_link,
+	TP_PROTO(char *name, char *cfg, char *func),
+	TP_ARGS(name, cfg, func),
+	TP_STRUCT__entry(
+		__string(group_name, name)
+		__string(cfg_name, cfg)
+		__string(func_name, func)
+	),
+	TP_fast_assign(
+		__assign_str(group_name, name);
+		__assign_str(cfg_name, cfg);
+		__assign_str(func_name, func)
+	),
+	TP_printk("gadget:%s cfg:%s link func:%s", __get_str(group_name),
+		__get_str(cfg_name), __get_str(func_name))
+);
+
 #endif /* __GADGET_TRACE_H */
 
 /* this part has to be here */
-- 
2.7.4