[PATCH 4/5] tracing: use NULL directly to create root level tracefs

[Wei Yang]

tracing_init_dentry() has two types of return value:

  * NULL if succeed
  * IS_ERR() if failed

If the function return error, the following check would return from the
function. So we are sure d_tracer passed in here is NULL.

This is a preparation for following cleanup.

Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxxxxxxxxxx>
---
 kernel/trace/trace_events.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index f6f55682d3e2..8b3aa57dcea6 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -3446,7 +3446,7 @@ __init int event_trace_init(void)
 	if (IS_ERR(d_tracer))
 		return 0;
 
-	entry = tracefs_create_file("available_events", 0444, d_tracer,
+	entry = tracefs_create_file("available_events", 0444, NULL,
 				    tr, &ftrace_avail_fops);
 	if (!entry)
 		pr_warn("Could not create tracefs 'available_events' entry\n");
@@ -3457,7 +3457,7 @@ __init int event_trace_init(void)
 	if (trace_define_common_fields())
 		pr_warn("tracing: Failed to allocate common fields");
 
-	ret = early_event_add_tracer(d_tracer, tr);
+	ret = early_event_add_tracer(NULL, tr);
 	if (ret)
 		return ret;
 
-- 
2.20.1 (Apple Git-117)