Commit 4f712a4d authored by Masami Hiramatsu's avatar Masami Hiramatsu Committed by Steven Rostedt (VMware)
Browse files

tracing/boot: Add instance node support 

Add instance node support to boot-time tracing. User can set
some options and event nodes under instance node.

 - ftrace.instance.INSTANCE[...]
   Add new INSTANCE instance. Some options and event nodes
   are acceptable for instance node.

Link: http://lkml.kernel.org/r/157867242413.17873.9814204526141500278.stgit@devnote2



Signed-off-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
parent 3fbe2d6e

kernel/trace/trace_boot.c

+38 −5
Original line number Diff line number Diff line
@@ -20,7 +20,7 @@ extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr, 
					  unsigned long size, int cpu_id);



static void __init

trace_boot_set_ftrace_options(struct trace_array *tr, struct xbc_node *node)

trace_boot_set_instance_options(struct trace_array *tr, struct xbc_node *node)

{

	struct xbc_node *anode;

	const char *p;
@@ -242,6 +242,40 @@ trace_boot_enable_tracer(struct trace_array *tr, struct xbc_node *node) 
	}

}



static void __init

trace_boot_init_one_instance(struct trace_array *tr, struct xbc_node *node)

{

	trace_boot_set_instance_options(tr, node);

	trace_boot_init_events(tr, node);

	trace_boot_enable_events(tr, node);

	trace_boot_enable_tracer(tr, node);

}



static void __init

trace_boot_init_instances(struct xbc_node *node)

{

	struct xbc_node *inode;

	struct trace_array *tr;

	const char *p;



	node = xbc_node_find_child(node, "instance");

	if (!node)

		return;



	xbc_node_for_each_child(node, inode) {

		p = xbc_node_get_data(inode);

		if (!p || *p == '\0')

			continue;



		tr = trace_array_get_by_name(p);

		if (IS_ERR(tr)) {

			pr_err("Failed to get trace instance %s\n", p);

			continue;

		}

		trace_boot_init_one_instance(tr, inode);

	}

}



static int __init trace_boot_init(void)

{

	struct xbc_node *trace_node;
@@ -255,10 +289,9 @@ static int __init trace_boot_init(void) 
	if (!tr)

		return 0;



	trace_boot_set_ftrace_options(tr, trace_node);

	trace_boot_init_events(tr, trace_node);

	trace_boot_enable_events(tr, trace_node);

	trace_boot_enable_tracer(tr, trace_node);

	/* Global trace array is also one instance */

	trace_boot_init_one_instance(tr, trace_node);

	trace_boot_init_instances(trace_node);



	return 0;

}

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