[mirror_ubuntu-artful-kernel.git] / kernel / trace / ring_buffer_benchmark.c

/*
 * ring buffer tester and benchmark
 *
 * Copyright (C) 2009 Steven Rostedt <srostedt@redhat.com>
 */
#include <linux/ring_buffer.h>
#include <linux/completion.h>
#include <linux/kthread.h>
#include <linux/module.h>
#include <linux/time.h>

struct rb_page {
	u64		ts;
	local_t		commit;
	char		data[4080];
};

/* run time and sleep time in seconds */
#define RUN_TIME	10
#define SLEEP_TIME	10

/* number of events for writer to wake up the reader */
static int wakeup_interval = 100;

static int reader_finish;
static struct completion read_start;
static struct completion read_done;

static struct ring_buffer *buffer;
static struct task_struct *producer;
static struct task_struct *consumer;
static unsigned long read;

static int disable_reader;
module_param(disable_reader, uint, 0644);
MODULE_PARM_DESC(disable_reader, "only run producer");

static int write_iteration = 50;
module_param(write_iteration, uint, 0644);
MODULE_PARM_DESC(write_iteration, "# of writes between timestamp readings");

static int read_events;

static int kill_test;

#define KILL_TEST()				\
	do {					\
		if (!kill_test) {		\
			kill_test = 1;		\
			WARN_ON(1);		\
		}				\
	} while (0)

enum event_status {
	EVENT_FOUND,
	EVENT_DROPPED,
};

static enum event_status read_event(int cpu)
{
	struct ring_buffer_event *event;
	int *entry;
	u64 ts;

	event = ring_buffer_consume(buffer, cpu, &ts);
	if (!event)
		return EVENT_DROPPED;

	entry = ring_buffer_event_data(event);
	if (*entry != cpu) {
		KILL_TEST();
		return EVENT_DROPPED;
	}

	read++;
	return EVENT_FOUND;
}

static enum event_status read_page(int cpu)
{
	struct ring_buffer_event *event;
	struct rb_page *rpage;
	unsigned long commit;
	void *bpage;
	int *entry;
	int ret;
	int inc;
	int i;

	bpage = ring_buffer_alloc_read_page(buffer);
	if (!bpage)
		return EVENT_DROPPED;

	ret = ring_buffer_read_page(buffer, &bpage, PAGE_SIZE, cpu, 1);
	if (ret >= 0) {
		rpage = bpage;
		commit = local_read(&rpage->commit);
		for (i = 0; i < commit && !kill_test; i += inc) {

			if (i >= (PAGE_SIZE - offsetof(struct rb_page, data))) {
				KILL_TEST();
				break;
			}

			inc = -1;
			event = (void *)&rpage->data[i];
			switch (event->type_len) {
			case RINGBUF_TYPE_PADDING:
				/* failed writes may be discarded events */
				if (!event->time_delta)
					KILL_TEST();
				inc = event->array[0] + 4;
				break;
			case RINGBUF_TYPE_TIME_EXTEND:
				inc = 8;
				break;
			case 0:
				entry = ring_buffer_event_data(event);
				if (*entry != cpu) {
					KILL_TEST();
					break;
				}
				read++;
				if (!event->array[0]) {
					KILL_TEST();
					break;
				}
				inc = event->array[0] + 4;
				break;
			default:
				entry = ring_buffer_event_data(event);
				if (*entry != cpu) {
					KILL_TEST();
					break;
				}
				read++;
				inc = ((event->type_len + 1) * 4);
			}
			if (kill_test)
				break;

			if (inc <= 0) {
				KILL_TEST();
				break;
			}
		}
	}
	ring_buffer_free_read_page(buffer, bpage);

	if (ret < 0)
		return EVENT_DROPPED;
	return EVENT_FOUND;
}

static void ring_buffer_consumer(void)
{
	/* toggle between reading pages and events */
	read_events ^= 1;

	read = 0;
	while (!reader_finish && !kill_test) {
		int found;

		do {
			int cpu;

			found = 0;
			for_each_online_cpu(cpu) {
				enum event_status stat;

				if (read_events)
					stat = read_event(cpu);
				else
					stat = read_page(cpu);

				if (kill_test)
					break;
				if (stat == EVENT_FOUND)
					found = 1;
			}
		} while (found && !kill_test);

		set_current_state(TASK_INTERRUPTIBLE);
		if (reader_finish)
			break;

		schedule();
		__set_current_state(TASK_RUNNING);
	}
	reader_finish = 0;
	complete(&read_done);
}

static void ring_buffer_producer(void)
{
	struct timeval start_tv;
	struct timeval end_tv;
	unsigned long long time;
	unsigned long long entries;
	unsigned long long overruns;
	unsigned long missed = 0;
	unsigned long hit = 0;
	unsigned long avg;
	int cnt = 0;

	/*
	 * Hammer the buffer for 10 secs (this may
	 * make the system stall)
	 */
	trace_printk("Starting ring buffer hammer\n");
	do_gettimeofday(&start_tv);
	do {
		struct ring_buffer_event *event;
		int *entry;
		int i;

		for (i = 0; i < write_iteration; i++) {
			event = ring_buffer_lock_reserve(buffer, 10);
			if (!event) {
				missed++;
			} else {
				hit++;
				entry = ring_buffer_event_data(event);
				*entry = smp_processor_id();
				ring_buffer_unlock_commit(buffer, event);
			}
		}
		do_gettimeofday(&end_tv);

		cnt++;
		if (consumer && !(cnt % wakeup_interval))
			wake_up_process(consumer);

#ifndef CONFIG_PREEMPT
		/*
		 * If we are a non preempt kernel, the 10 second run will
		 * stop everything while it runs. Instead, we will call
		 * cond_resched and also add any time that was lost by a
		 * rescedule.
		 *
		 * Do a cond resched at the same frequency we would wake up
		 * the reader.
		 */
		if (cnt % wakeup_interval)
			cond_resched();
#endif

	} while (end_tv.tv_sec < (start_tv.tv_sec + RUN_TIME) && !kill_test);
	trace_printk("End ring buffer hammer\n");

	if (consumer) {
		/* Init both completions here to avoid races */
		init_completion(&read_start);
		init_completion(&read_done);
		/* the completions must be visible before the finish var */
		smp_wmb();
		reader_finish = 1;
		/* finish var visible before waking up the consumer */
		smp_wmb();
		wake_up_process(consumer);
		wait_for_completion(&read_done);
	}

	time = end_tv.tv_sec - start_tv.tv_sec;
	time *= USEC_PER_SEC;
	time += (long long)((long)end_tv.tv_usec - (long)start_tv.tv_usec);

	entries = ring_buffer_entries(buffer);
	overruns = ring_buffer_overruns(buffer);

	if (kill_test)
		trace_printk("ERROR!\n");
	trace_printk("Time:     %lld (usecs)\n", time);
	trace_printk("Overruns: %lld\n", overruns);
	if (disable_reader)
		trace_printk("Read:     (reader disabled)\n");
	else
		trace_printk("Read:     %ld  (by %s)\n", read,
			read_events ? "events" : "pages");
	trace_printk("Entries:  %lld\n", entries);
	trace_printk("Total:    %lld\n", entries + overruns + read);
	trace_printk("Missed:   %ld\n", missed);
	trace_printk("Hit:      %ld\n", hit);

	/* Convert time from usecs to millisecs */
	do_div(time, USEC_PER_MSEC);
	if (time)
		hit /= (long)time;
	else
		trace_printk("TIME IS ZERO??\n");

	trace_printk("Entries per millisec: %ld\n", hit);

	if (hit) {
		/* Calculate the average time in nanosecs */
		avg = NSEC_PER_MSEC / hit;
		trace_printk("%ld ns per entry\n", avg);
	}

	if (missed) {
		if (time)
			missed /= (long)time;

		trace_printk("Total iterations per millisec: %ld\n",
			     hit + missed);

		/* it is possible that hit + missed will overflow and be zero */
		if (!(hit + missed)) {
			trace_printk("hit + missed overflowed and totalled zero!\n");
			hit--; /* make it non zero */
		}

		/* Caculate the average time in nanosecs */
		avg = NSEC_PER_MSEC / (hit + missed);
		trace_printk("%ld ns per entry\n", avg);
	}
}

static void wait_to_die(void)
{
	set_current_state(TASK_INTERRUPTIBLE);
	while (!kthread_should_stop()) {
		schedule();
		set_current_state(TASK_INTERRUPTIBLE);
	}
	__set_current_state(TASK_RUNNING);
}

static int ring_buffer_consumer_thread(void *arg)
{
	while (!kthread_should_stop() && !kill_test) {
		complete(&read_start);

		ring_buffer_consumer();

		set_current_state(TASK_INTERRUPTIBLE);
		if (kthread_should_stop() || kill_test)
			break;

		schedule();
		__set_current_state(TASK_RUNNING);
	}
	__set_current_state(TASK_RUNNING);

	if (kill_test)
		wait_to_die();

	return 0;
}

static int ring_buffer_producer_thread(void *arg)
{
	init_completion(&read_start);

	while (!kthread_should_stop() && !kill_test) {
		ring_buffer_reset(buffer);

		if (consumer) {
			smp_wmb();
			wake_up_process(consumer);
			wait_for_completion(&read_start);
		}

		ring_buffer_producer();

		trace_printk("Sleeping for 10 secs\n");
		set_current_state(TASK_INTERRUPTIBLE);
		schedule_timeout(HZ * SLEEP_TIME);
		__set_current_state(TASK_RUNNING);
	}

	if (kill_test)
		wait_to_die();

	return 0;
}

static int __init ring_buffer_benchmark_init(void)
{
	int ret;

	/* make a one meg buffer in overwite mode */
	buffer = ring_buffer_alloc(1000000, RB_FL_OVERWRITE);
	if (!buffer)
		return -ENOMEM;

	if (!disable_reader) {
		consumer = kthread_create(ring_buffer_consumer_thread,
					  NULL, "rb_consumer");
		ret = PTR_ERR(consumer);
		if (IS_ERR(consumer))
			goto out_fail;
	}

	producer = kthread_run(ring_buffer_producer_thread,
			       NULL, "rb_producer");
	ret = PTR_ERR(producer);

	if (IS_ERR(producer))
		goto out_kill;

	/*
	 * Run them as low-prio background tasks by default:
	 */
	set_user_nice(consumer, 19);
	set_user_nice(producer, 19);

	return 0;

 out_kill:
	if (consumer)
		kthread_stop(consumer);

 out_fail:
	ring_buffer_free(buffer);
	return ret;
}

static void __exit ring_buffer_benchmark_exit(void)
{
	kthread_stop(producer);
	if (consumer)
		kthread_stop(consumer);
	ring_buffer_free(buffer);
}

module_init(ring_buffer_benchmark_init);
module_exit(ring_buffer_benchmark_exit);

MODULE_AUTHOR("Steven Rostedt");
MODULE_DESCRIPTION("ring_buffer_benchmark");
MODULE_LICENSE("GPL");
Commit	Line	Data
5092dbc9 SR	1	/*
	2	* ring buffer tester and benchmark
	3	*
	4	* Copyright (C) 2009 Steven Rostedt <srostedt@redhat.com>
	5	*/
	6	#include <linux/ring_buffer.h>
	7	#include <linux/completion.h>
	8	#include <linux/kthread.h>
	9	#include <linux/module.h>
	10	#include <linux/time.h>
	11
	12	struct rb_page {
	13	u64 ts;
	14	local_t commit;
	15	char data[4080];
	16	};
	17
	18	/* run time and sleep time in seconds */
	19	#define RUN_TIME 10
	20	#define SLEEP_TIME 10
	21
	22	/* number of events for writer to wake up the reader */
	23	static int wakeup_interval = 100;
	24
	25	static int reader_finish;
	26	static struct completion read_start;
	27	static struct completion read_done;
	28
	29	static struct ring_buffer *buffer;
	30	static struct task_struct *producer;
	31	static struct task_struct *consumer;
	32	static unsigned long read;
	33
	34	static int disable_reader;
	35	module_param(disable_reader, uint, 0644);
	36	MODULE_PARM_DESC(disable_reader, "only run producer");
	37
a6f0eb6a SR	38	static int write_iteration = 50;
	39	module_param(write_iteration, uint, 0644);
	40	MODULE_PARM_DESC(write_iteration, "# of writes between timestamp readings");
	41
5092dbc9 SR	42	static int read_events;
	43
	44	static int kill_test;
	45
	46	#define KILL_TEST() \
	47	do { \
	48	if (!kill_test) { \
	49	kill_test = 1; \
	50	WARN_ON(1); \
	51	} \
	52	} while (0)
	53
	54	enum event_status {
	55	EVENT_FOUND,
	56	EVENT_DROPPED,
	57	};
	58
	59	static enum event_status read_event(int cpu)
	60	{
	61	struct ring_buffer_event *event;
	62	int *entry;
	63	u64 ts;
	64
	65	event = ring_buffer_consume(buffer, cpu, &ts);
	66	if (!event)
	67	return EVENT_DROPPED;
	68
	69	entry = ring_buffer_event_data(event);
	70	if (*entry != cpu) {
	71	KILL_TEST();
	72	return EVENT_DROPPED;
	73	}
	74
	75	read++;
	76	return EVENT_FOUND;
	77	}
	78
	79	static enum event_status read_page(int cpu)
	80	{
	81	struct ring_buffer_event *event;
	82	struct rb_page *rpage;
	83	unsigned long commit;
	84	void *bpage;
	85	int *entry;
	86	int ret;
	87	int inc;
	88	int i;
	89
	90	bpage = ring_buffer_alloc_read_page(buffer);
00c81a58 SR	91	if (!bpage)
	92	return EVENT_DROPPED;
	93
5092dbc9 SR	94	ret = ring_buffer_read_page(buffer, &bpage, PAGE_SIZE, cpu, 1);
	95	if (ret >= 0) {
	96	rpage = bpage;
	97	commit = local_read(&rpage->commit);
	98	for (i = 0; i < commit && !kill_test; i += inc) {
	99
	100	if (i >= (PAGE_SIZE - offsetof(struct rb_page, data))) {
	101	KILL_TEST();
	102	break;
	103	}
	104
	105	inc = -1;
	106	event = (void *)&rpage->data[i];
	107	switch (event->type_len) {
	108	case RINGBUF_TYPE_PADDING:
9086c7b9 SR	109	/* failed writes may be discarded events */
	110	if (!event->time_delta)
	111	KILL_TEST();
	112	inc = event->array[0] + 4;
5092dbc9 SR	113	break;
	114	case RINGBUF_TYPE_TIME_EXTEND:
	115	inc = 8;
	116	break;
	117	case 0:
	118	entry = ring_buffer_event_data(event);
	119	if (*entry != cpu) {
	120	KILL_TEST();
	121	break;
	122	}
	123	read++;
	124	if (!event->array[0]) {
	125	KILL_TEST();
	126	break;
	127	}
9086c7b9	128	inc = event->array[0] + 4;
5092dbc9 SR	129	break;
	130	default:
	131	entry = ring_buffer_event_data(event);
	132	if (*entry != cpu) {
	133	KILL_TEST();
	134	break;
	135	}
	136	read++;
	137	inc = ((event->type_len + 1) * 4);
	138	}
	139	if (kill_test)
	140	break;
	141
	142	if (inc <= 0) {
	143	KILL_TEST();
	144	break;
	145	}
	146	}
	147	}
	148	ring_buffer_free_read_page(buffer, bpage);
	149
	150	if (ret < 0)
	151	return EVENT_DROPPED;
	152	return EVENT_FOUND;
	153	}
	154
	155	static void ring_buffer_consumer(void)
	156	{
	157	/* toggle between reading pages and events */
	158	read_events ^= 1;
	159
	160	read = 0;
	161	while (!reader_finish && !kill_test) {
	162	int found;
	163
	164	do {
	165	int cpu;
	166
	167	found = 0;
	168	for_each_online_cpu(cpu) {
	169	enum event_status stat;
	170
	171	if (read_events)
	172	stat = read_event(cpu);
	173	else
	174	stat = read_page(cpu);
	175
	176	if (kill_test)
	177	break;
	178	if (stat == EVENT_FOUND)
	179	found = 1;
	180	}
	181	} while (found && !kill_test);
	182
	183	set_current_state(TASK_INTERRUPTIBLE);
	184	if (reader_finish)
	185	break;
	186
	187	schedule();
	188	__set_current_state(TASK_RUNNING);
	189	}
	190	reader_finish = 0;
	191	complete(&read_done);
	192	}
193
194	static void ring_buffer_producer(void)
195	{
196	struct timeval start_tv;
197	struct timeval end_tv;
198	unsigned long long time;
199	unsigned long long entries;
200	unsigned long long overruns;
201	unsigned long missed = 0;
202	unsigned long hit = 0;
203	unsigned long avg;
204	int cnt = 0;
205
206	/*
207	* Hammer the buffer for 10 secs (this may
208	* make the system stall)
209	*/
4b221f03	210	trace_printk("Starting ring buffer hammer\n");
5092dbc9 SR	211	do_gettimeofday(&start_tv);
	212	do {
	213	struct ring_buffer_event *event;
	214	int *entry;
a6f0eb6a SR	215	int i;
	216
	217	for (i = 0; i < write_iteration; i++) {
	218	event = ring_buffer_lock_reserve(buffer, 10);
	219	if (!event) {
	220	missed++;
	221	} else {
	222	hit++;
	223	entry = ring_buffer_event_data(event);
	224	*entry = smp_processor_id();
	225	ring_buffer_unlock_commit(buffer, event);
	226	}
5092dbc9 SR	227	}
	228	do_gettimeofday(&end_tv);
	229
0574ea42 SR	230	cnt++;
0574ea42 SR	231	if (consumer && !(cnt % wakeup_interval))
5092dbc9 SR	232	wake_up_process(consumer);
5092dbc9 SR	233
0574ea42	234	#ifndef CONFIG_PREEMPT
29c8000e SR	235	/*
	236	* If we are a non preempt kernel, the 10 second run will
	237	* stop everything while it runs. Instead, we will call
	238	* cond_resched and also add any time that was lost by a
	239	* rescedule.
0574ea42 SR	240	*
	241	* Do a cond resched at the same frequency we would wake up
	242	* the reader.
29c8000e	243	*/
0574ea42 SR	244	if (cnt % wakeup_interval)
	245	cond_resched();
	246	#endif
3e07a4f6	247
5092dbc9	248	} while (end_tv.tv_sec < (start_tv.tv_sec + RUN_TIME) && !kill_test);
4b221f03	249	trace_printk("End ring buffer hammer\n");
5092dbc9 SR	250
	251	if (consumer) {
	252	/* Init both completions here to avoid races */
	253	init_completion(&read_start);
	254	init_completion(&read_done);
	255	/* the completions must be visible before the finish var */
	256	smp_wmb();
	257	reader_finish = 1;
	258	/* finish var visible before waking up the consumer */
	259	smp_wmb();
	260	wake_up_process(consumer);
	261	wait_for_completion(&read_done);
	262	}
	263
	264	time = end_tv.tv_sec - start_tv.tv_sec;
5a772b2b	265	time *= USEC_PER_SEC;
5092dbc9 SR	266	time += (long long)((long)end_tv.tv_usec - (long)start_tv.tv_usec);
	267
	268	entries = ring_buffer_entries(buffer);
	269	overruns = ring_buffer_overruns(buffer);
	270
	271	if (kill_test)
4b221f03 SR	272	trace_printk("ERROR!\n");
	273	trace_printk("Time: %lld (usecs)\n", time);
	274	trace_printk("Overruns: %lld\n", overruns);
5092dbc9	275	if (disable_reader)
4b221f03	276	trace_printk("Read: (reader disabled)\n");
5092dbc9	277	else
4b221f03	278	trace_printk("Read: %ld (by %s)\n", read,
5092dbc9	279	read_events ? "events" : "pages");
4b221f03 SR	280	trace_printk("Entries: %lld\n", entries);
	281	trace_printk("Total: %lld\n", entries + overruns + read);
	282	trace_printk("Missed: %ld\n", missed);
	283	trace_printk("Hit: %ld\n", hit);
5092dbc9	284
5a772b2b SR	285	/* Convert time from usecs to millisecs */
5a772b2b SR	286	do_div(time, USEC_PER_MSEC);
5092dbc9 SR	287	if (time)
	288	hit /= (long)time;
	289	else
4b221f03	290	trace_printk("TIME IS ZERO??\n");
5092dbc9	291
4b221f03	292	trace_printk("Entries per millisec: %ld\n", hit);
5092dbc9 SR	293
5092dbc9 SR	294	if (hit) {
5a772b2b SR	295	/* Calculate the average time in nanosecs */
5a772b2b SR	296	avg = NSEC_PER_MSEC / hit;
4b221f03	297	trace_printk("%ld ns per entry\n", avg);
5092dbc9	298	}
7da3046d	299
7da3046d SR	300	if (missed) {
	301	if (time)
	302	missed /= (long)time;
	303
4b221f03 SR	304	trace_printk("Total iterations per millisec: %ld\n",
4b221f03 SR	305	hit + missed);
7da3046d	306
d988ff94 SR	307	/* it is possible that hit + missed will overflow and be zero */
d988ff94 SR	308	if (!(hit + missed)) {
4b221f03	309	trace_printk("hit + missed overflowed and totalled zero!\n");
d988ff94 SR	310	hit--; /* make it non zero */
	311	}
	312
5a772b2b SR	313	/* Caculate the average time in nanosecs */
5a772b2b SR	314	avg = NSEC_PER_MSEC / (hit + missed);
4b221f03	315	trace_printk("%ld ns per entry\n", avg);
7da3046d	316	}
5092dbc9 SR	317	}
	318
	319	static void wait_to_die(void)
	320	{
	321	set_current_state(TASK_INTERRUPTIBLE);
	322	while (!kthread_should_stop()) {
	323	schedule();
	324	set_current_state(TASK_INTERRUPTIBLE);
	325	}
	326	__set_current_state(TASK_RUNNING);
	327	}
	328
	329	static int ring_buffer_consumer_thread(void *arg)
	330	{
	331	while (!kthread_should_stop() && !kill_test) {
	332	complete(&read_start);
	333
	334	ring_buffer_consumer();
	335
	336	set_current_state(TASK_INTERRUPTIBLE);
	337	if (kthread_should_stop() \|\| kill_test)
	338	break;
	339
	340	schedule();
	341	__set_current_state(TASK_RUNNING);
	342	}
	343	__set_current_state(TASK_RUNNING);
	344
	345	if (kill_test)
	346	wait_to_die();
	347
	348	return 0;
	349	}
	350
	351	static int ring_buffer_producer_thread(void *arg)
	352	{
	353	init_completion(&read_start);
	354
	355	while (!kthread_should_stop() && !kill_test) {
	356	ring_buffer_reset(buffer);
	357
	358	if (consumer) {
	359	smp_wmb();
	360	wake_up_process(consumer);
	361	wait_for_completion(&read_start);
	362	}
	363
	364	ring_buffer_producer();
	365
4b221f03	366	trace_printk("Sleeping for 10 secs\n");
5092dbc9 SR	367	set_current_state(TASK_INTERRUPTIBLE);
	368	schedule_timeout(HZ * SLEEP_TIME);
	369	__set_current_state(TASK_RUNNING);
	370	}
	371
	372	if (kill_test)
	373	wait_to_die();
	374
	375	return 0;
	376	}
	377
	378	static int __init ring_buffer_benchmark_init(void)
	379	{
	380	int ret;
	381
	382	/* make a one meg buffer in overwite mode */
	383	buffer = ring_buffer_alloc(1000000, RB_FL_OVERWRITE);
	384	if (!buffer)
	385	return -ENOMEM;
	386
	387	if (!disable_reader) {
	388	consumer = kthread_create(ring_buffer_consumer_thread,
	389	NULL, "rb_consumer");
	390	ret = PTR_ERR(consumer);
	391	if (IS_ERR(consumer))
	392	goto out_fail;
	393	}
	394
	395	producer = kthread_run(ring_buffer_producer_thread,
	396	NULL, "rb_producer");
	397	ret = PTR_ERR(producer);
	398
	399	if (IS_ERR(producer))
	400	goto out_kill;
	401
98e4833b IM	402	/*
	403	* Run them as low-prio background tasks by default:
	404	*/
	405	set_user_nice(consumer, 19);
	406	set_user_nice(producer, 19);
	407
5092dbc9 SR	408	return 0;
	409
	410	out_kill:
	411	if (consumer)
	412	kthread_stop(consumer);
	413
	414	out_fail:
	415	ring_buffer_free(buffer);
	416	return ret;
	417	}
	418
	419	static void __exit ring_buffer_benchmark_exit(void)
	420	{
	421	kthread_stop(producer);
	422	if (consumer)
	423	kthread_stop(consumer);
	424	ring_buffer_free(buffer);
	425	}
	426
	427	module_init(ring_buffer_benchmark_init);
	428	module_exit(ring_buffer_benchmark_exit);
	429
	430	MODULE_AUTHOR("Steven Rostedt");
	431	MODULE_DESCRIPTION("ring_buffer_benchmark");
	432	MODULE_LICENSE("GPL");