1/*
  2 * trace context switch
  3 *
  4 * Copyright (C) 2007 Steven Rostedt <srostedt@redhat.com>
  5 *
  6 */
  7#include <linux/module.h>
  8#include <linux/kallsyms.h>
  9#include <linux/uaccess.h>
 10#include <linux/ftrace.h>
 11#include <trace/events/sched.h>
 12
 13#include "trace.h"
 14
 15static int			sched_ref;
 16static DEFINE_MUTEX(sched_register_mutex);
 17
 18static void
 19probe_sched_switch(void *ignore, bool preempt,
 20		   struct task_struct *prev, struct task_struct *next)
 21{
 22	if (unlikely(!sched_ref))
 23		return;
 24
 25	tracing_record_cmdline(prev);
 26	tracing_record_cmdline(next);
 27}
 28
 29static void
 30probe_sched_wakeup(void *ignore, struct task_struct *wakee)
 31{
 32	if (unlikely(!sched_ref))
 33		return;
 34
 35	tracing_record_cmdline(current);
 36}
 37
 38static int tracing_sched_register(void)
 39{
 40	int ret;
 41
 42	ret = register_trace_sched_wakeup(probe_sched_wakeup, NULL);
 43	if (ret) {
 44		pr_info("wakeup trace: Couldn't activate tracepoint"
 45			" probe to kernel_sched_wakeup\n");
 46		return ret;
 47	}
 48
 49	ret = register_trace_sched_wakeup_new(probe_sched_wakeup, NULL);
 50	if (ret) {
 51		pr_info("wakeup trace: Couldn't activate tracepoint"
 52			" probe to kernel_sched_wakeup_new\n");
 53		goto fail_deprobe;
 54	}
 55
 56	ret = register_trace_sched_switch(probe_sched_switch, NULL);
 57	if (ret) {
 58		pr_info("sched trace: Couldn't activate tracepoint"
 59			" probe to kernel_sched_switch\n");
 60		goto fail_deprobe_wake_new;
 61	}
 62
 63	return ret;
 64fail_deprobe_wake_new:
 65	unregister_trace_sched_wakeup_new(probe_sched_wakeup, NULL);
 66fail_deprobe:
 67	unregister_trace_sched_wakeup(probe_sched_wakeup, NULL);
 68	return ret;
 69}
 70
 71static void tracing_sched_unregister(void)
 72{
 73	unregister_trace_sched_switch(probe_sched_switch, NULL);
 74	unregister_trace_sched_wakeup_new(probe_sched_wakeup, NULL);
 75	unregister_trace_sched_wakeup(probe_sched_wakeup, NULL);
 76}
 77
 78static void tracing_start_sched_switch(void)
 79{
 80	mutex_lock(&sched_register_mutex);
 81	if (!(sched_ref++))
 82		tracing_sched_register();
 83	mutex_unlock(&sched_register_mutex);
 84}
 85
 86static void tracing_stop_sched_switch(void)
 87{
 88	mutex_lock(&sched_register_mutex);
 89	if (!(--sched_ref))
 90		tracing_sched_unregister();
 91	mutex_unlock(&sched_register_mutex);
 92}
 93
 94void tracing_start_cmdline_record(void)
 95{
 96	tracing_start_sched_switch();
 97}
 98
 99void tracing_stop_cmdline_record(void)
100{
101	tracing_stop_sched_switch();
102}

  1/*
  2 * trace context switch
  3 *
  4 * Copyright (C) 2007 Steven Rostedt <srostedt@redhat.com>
  5 *
  6 */
  7#include <linux/module.h>
  8#include <linux/kallsyms.h>
  9#include <linux/uaccess.h>
 10#include <linux/ftrace.h>
 11#include <trace/events/sched.h>
 12
 13#include "trace.h"
 14
 15static int			sched_ref;
 16static DEFINE_MUTEX(sched_register_mutex);
 17
 18static void
 19probe_sched_switch(void *ignore, bool preempt,
 20		   struct task_struct *prev, struct task_struct *next)
 21{
 22	if (unlikely(!sched_ref))
 23		return;
 24
 25	tracing_record_cmdline(prev);
 26	tracing_record_cmdline(next);
 27}
 28
 29static void
 30probe_sched_wakeup(void *ignore, struct task_struct *wakee)
 31{
 32	if (unlikely(!sched_ref))
 33		return;
 34
 35	tracing_record_cmdline(current);
 36}
 37
 38static int tracing_sched_register(void)
 39{
 40	int ret;
 41
 42	ret = register_trace_sched_wakeup(probe_sched_wakeup, NULL);
 43	if (ret) {
 44		pr_info("wakeup trace: Couldn't activate tracepoint"
 45			" probe to kernel_sched_wakeup\n");
 46		return ret;
 47	}
 48
 49	ret = register_trace_sched_wakeup_new(probe_sched_wakeup, NULL);
 50	if (ret) {
 51		pr_info("wakeup trace: Couldn't activate tracepoint"
 52			" probe to kernel_sched_wakeup_new\n");
 53		goto fail_deprobe;
 54	}
 55
 56	ret = register_trace_sched_switch(probe_sched_switch, NULL);
 57	if (ret) {
 58		pr_info("sched trace: Couldn't activate tracepoint"
 59			" probe to kernel_sched_switch\n");
 60		goto fail_deprobe_wake_new;
 61	}
 62
 63	return ret;
 64fail_deprobe_wake_new:
 65	unregister_trace_sched_wakeup_new(probe_sched_wakeup, NULL);
 66fail_deprobe:
 67	unregister_trace_sched_wakeup(probe_sched_wakeup, NULL);
 68	return ret;
 69}
 70
 71static void tracing_sched_unregister(void)
 72{
 73	unregister_trace_sched_switch(probe_sched_switch, NULL);
 74	unregister_trace_sched_wakeup_new(probe_sched_wakeup, NULL);
 75	unregister_trace_sched_wakeup(probe_sched_wakeup, NULL);
 76}
 77
 78static void tracing_start_sched_switch(void)
 79{
 80	mutex_lock(&sched_register_mutex);
 81	if (!(sched_ref++))
 82		tracing_sched_register();
 83	mutex_unlock(&sched_register_mutex);
 84}
 85
 86static void tracing_stop_sched_switch(void)
 87{
 88	mutex_lock(&sched_register_mutex);
 89	if (!(--sched_ref))
 90		tracing_sched_unregister();
 91	mutex_unlock(&sched_register_mutex);
 92}
 93
 94void tracing_start_cmdline_record(void)
 95{
 96	tracing_start_sched_switch();
 97}
 98
 99void tracing_stop_cmdline_record(void)
100{
101	tracing_stop_sched_switch();
102}