Commit 4f99f848 authored by Masami Hiramatsu's avatar Masami Hiramatsu Committed by Steven Rostedt (VMware)
Browse files

tracing/boot: Add per-group/all events enablement 

Add ftrace.event.<GROUP>.enable and ftrace.event.enable
boot-time tracing, which enables all events under
given GROUP and all events respectivly.

Link: https://lkml.kernel.org/r/162264438005.302580.12019174481201855444.stgit@devnote2



Signed-off-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
parent 6c610dba

kernel/trace/trace_boot.c

+25 −2
Original line number Diff line number Diff line
@@ -225,15 +225,38 @@ static void __init 
trace_boot_init_events(struct trace_array *tr, struct xbc_node *node)

{

	struct xbc_node *gnode, *enode;

	bool enable, enable_all = false;

	const char *data;



	node = xbc_node_find_child(node, "event");

	if (!node)

		return;

	/* per-event key starts with "event.GROUP.EVENT" */

	xbc_node_for_each_child(node, gnode)

		xbc_node_for_each_child(gnode, enode)

	xbc_node_for_each_child(node, gnode) {

		data = xbc_node_get_data(gnode);

		if (!strcmp(data, "enable")) {

			enable_all = true;

			continue;

		}

		enable = false;

		xbc_node_for_each_child(gnode, enode) {

			data = xbc_node_get_data(enode);

			if (!strcmp(data, "enable")) {

				enable = true;

				continue;

			}

			trace_boot_init_one_event(tr, gnode, enode);

		}

		/* Event enablement must be done after event settings */

		if (enable) {

			data = xbc_node_get_data(gnode);

			trace_array_set_clr_event(tr, data, NULL, true);

		}

	}

	/* Ditto */

	if (enable_all)

		trace_array_set_clr_event(tr, NULL, NULL, true);

}

#else

#define trace_boot_enable_events(tr, node) do {} while (0)

#define trace_boot_init_events(tr, node) do {} while (0)