Commit 7d436400 authored by Steven Rostedt (Red Hat)'s avatar Steven Rostedt (Red Hat) Committed by Steven Rostedt
Browse files

tracing: Add error checks to creation of event files 



The creation of the set_event_pid file was assigned to a variable "entry"
but that variable was never used. Ideally, it should be used to check if the
file was created and warn if it was not.

The files header_page, header_event should also be checked and a warning if
they fail to be created.

The "enable" file was moved up, as it is a more crucial file to have and a
hard failure (return -ENOMEM) should be returned if it is not created.

Reported-by: default avatarDavid Binderman <dcb314@hotmail.com>
Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
parent 9dfed80d

kernel/trace/trace_events.c

+21 −9
Original line number Diff line number Diff line
@@ -2843,20 +2843,32 @@ create_event_toplevel_files(struct dentry *parent, struct trace_array *tr) 
		return -ENOMEM;

	}



	entry = trace_create_file("enable", 0644, d_events,

				  tr, &ftrace_tr_enable_fops);

	if (!entry) {

		pr_warn("Could not create tracefs 'enable' entry\n");

		return -ENOMEM;

	}



	/* There are not as crucial, just warn if they are not created */



	entry = tracefs_create_file("set_event_pid", 0644, parent,

				    tr, &ftrace_set_event_pid_fops);

	if (!entry)

		pr_warn("Could not create tracefs 'set_event_pid' entry\n");



	/* ring buffer internal formats */

	trace_create_file("header_page", 0444, d_events,

	entry = trace_create_file("header_page", 0444, d_events,

				  ring_buffer_print_page_header,

				  &ftrace_show_header_fops);

	if (!entry)

		pr_warn("Could not create tracefs 'header_page' entry\n");



	trace_create_file("header_event", 0444, d_events,

	entry = trace_create_file("header_event", 0444, d_events,

				  ring_buffer_print_entry_header,

				  &ftrace_show_header_fops);



	trace_create_file("enable", 0644, d_events,

			  tr, &ftrace_tr_enable_fops);

	if (!entry)

		pr_warn("Could not create tracefs 'header_event' entry\n");



	tr->event_dir = d_events;

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