/* * ring buffer based function tracer * * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> * * Based on code from the latency_tracer, that is: * *  Copyright (C) 2004-2006 Ingo Molnar *  Copyright (C) 2004 William Lee Irwin III */#include <linux/debugfs.h>#include <linux/uaccess.h>#include <linux/ftrace.h>#include <linux/fs.h> #include "trace.h" static void function_reset(struct trace_array *tr){	int cpu; 	tr->time_start = ftrace_now(tr->cpu); 	for_each_online_cpu(cpu)		tracing_reset(tr, cpu);} static void start_function_trace(struct trace_array *tr){	tr->cpu = get_cpu();	function_reset(tr);	put_cpu(); 	tracing_start_cmdline_record();	tracing_start_function_trace();} static void stop_function_trace(struct trace_array *tr){	tracing_stop_function_trace();	tracing_stop_cmdline_record();} static void function_trace_init(struct trace_array *tr){	if (tr->ctrl)		start_function_trace(tr);} static void function_trace_reset(struct trace_array *tr){	if (tr->ctrl)		stop_function_trace(tr);} static void function_trace_ctrl_update(struct trace_array *tr){	if (tr->ctrl)		start_function_trace(tr);	else		stop_function_trace(tr);} static struct tracer function_trace __read_mostly ={	.name	     = "function",	.init	     = function_trace_init,	.reset	     = function_trace_reset,	.ctrl_update = function_trace_ctrl_update,#ifdef CONFIG_FTRACE_SELFTEST	.selftest    = trace_selftest_startup_function,#endif}; static __init int init_function_trace(void){	return register_tracer(&function_trace);} device_initcall(init_function_trace);