Documentation/perf_counter/builtin-record.c - kernel/hikey-linaro - Gitiles



 #include "perf.h"
 #include "util/util.h"
 #include "util/parse-options.h"
 #include "util/parse-events.h"

 #include <sched.h>

 #define ALIGN(x, a)		__ALIGN_MASK(x, (typeof(x))(a)-1)
 #define __ALIGN_MASK(x, mask)	(((x)+(mask))&~(mask))

 static int			default_interval = 100000;
 static int			event_count[MAX_COUNTERS];

 static int			fd[MAX_NR_CPUS][MAX_COUNTERS];
 static int			nr_cpus				=  0;
 static unsigned int		page_size;
 static unsigned int		mmap_pages			= 16;
 static int			output;
 static const char		*output_name			= "output.perf";
 static int			group				= 0;
 static unsigned int		realtime_prio			= 0;
 static int			system_wide			= 0;
 static pid_t			target_pid			= -1;
 static int			inherit				= 1;
 static int			nmi				= 1;

 const unsigned int default_count[] = {
 	1000000,
 	1000000,
 	  10000,
 	  10000,
 	1000000,
 	  10000,
 };

 struct mmap_data {
 	int counter;
 	void *base;
 	unsigned int mask;
 	unsigned int prev;
 };

 static unsigned int mmap_read_head(struct mmap_data *md)
 {
 	struct perf_counter_mmap_page *pc = md->base;
 	int head;

 	head = pc->data_head;
 	rmb();

 	return head;
 }

 static long events;
 static struct timeval last_read, this_read;

 static void mmap_read(struct mmap_data *md)
 {
 	unsigned int head = mmap_read_head(md);
 	unsigned int old = md->prev;
 	unsigned char *data = md->base + page_size;
 	unsigned long size;
 	void *buf;
 	int diff;

 	gettimeofday(&this_read, NULL);

 	/*
 	 * If we're further behind than half the buffer, there's a chance
 	 * the writer will bite our tail and screw up the events under us.
 	 *
 	 * If we somehow ended up ahead of the head, we got messed up.
 	 *
 	 * In either case, truncate and restart at head.
 	 */
 	diff = head - old;
 	if (diff > md->mask / 2 || diff < 0) {
 		struct timeval iv;
 		unsigned long msecs;

 		timersub(&this_read, &last_read, &iv);
 		msecs = iv.tv_sec*1000 + iv.tv_usec/1000;

 		fprintf(stderr, "WARNING: failed to keep up with mmap data."
 				"  Last read %lu msecs ago.\n", msecs);

 		/*
 		 * head points to a known good entry, start there.
 		 */
 		old = head;
 	}

 	last_read = this_read;

 	if (old != head)
 		events++;

 	size = head - old;

 	if ((old & md->mask) + size != (head & md->mask)) {
 		buf = &data[old & md->mask];
 		size = md->mask + 1 - (old & md->mask);
 		old += size;
 		while (size) {
 			int ret = write(output, buf, size);
 			if (ret < 0) {
 				perror("failed to write");
 				exit(-1);
 			}
 			size -= ret;
 			buf += ret;
 		}
 	}

 	buf = &data[old & md->mask];
 	size = head - old;
 	old += size;
 	while (size) {
 		int ret = write(output, buf, size);
 		if (ret < 0) {
 			perror("failed to write");
 			exit(-1);
 		}
 		size -= ret;
 		buf += ret;
 	}

 	md->prev = old;
 }

 static volatile int done = 0;

 static void sig_handler(int sig)
 {
 	done = 1;
 }

 static struct pollfd event_array[MAX_NR_CPUS * MAX_COUNTERS];
 static struct mmap_data mmap_array[MAX_NR_CPUS][MAX_COUNTERS];

 static int nr_poll;
 static int nr_cpu;

 struct mmap_event {
 	struct perf_event_header header;
 	__u32 pid, tid;
 	__u64 start;
 	__u64 len;
 	__u64 pgoff;
 	char filename[PATH_MAX];
 };
 struct comm_event {
 	struct perf_event_header header;
 	__u32 pid,tid;
 	char comm[16];
 };

 static pid_t pid_synthesize_comm_event(pid_t pid)
 {
 	char filename[PATH_MAX];
 	char bf[BUFSIZ];
 	struct comm_event comm_ev;
 	size_t size;
 	int fd;

 	snprintf(filename, sizeof(filename), "/proc/%d/stat", pid);

 	fd = open(filename, O_RDONLY);
 	if (fd < 0) {
 		fprintf(stderr, "couldn't open %s\n", filename);
 		exit(EXIT_FAILURE);
 	}
 	if (read(fd, bf, sizeof(bf)) < 0) {
 		fprintf(stderr, "couldn't read %s\n", filename);
 		exit(EXIT_FAILURE);
 	}
 	close(fd);

 	pid_t spid, ppid;
 	char state;
 	char comm[18];

 	memset(&comm_ev, 0, sizeof(comm_ev));
         int nr = sscanf(bf, "%d %s %c %d %d ",
 			&spid, comm, &state, &ppid, &comm_ev.pid);
 	if (nr != 5) {
 		fprintf(stderr, "couldn't get COMM and pgid, malformed %s\n",
 			filename);
 		exit(EXIT_FAILURE);
 	}
 	comm_ev.header.type = PERF_EVENT_COMM;
 	comm_ev.tid = pid;
 	size = strlen(comm);
 	comm[--size] = '\0'; /* Remove the ')' at the end */
 	--size; /* Remove the '(' at the begin */
 	memcpy(comm_ev.comm, comm + 1, size);
 	size = ALIGN(size, sizeof(uint64_t));
 	comm_ev.header.size = sizeof(comm_ev) - (sizeof(comm_ev.comm) - size);
 	int ret = write(output, &comm_ev, comm_ev.header.size);
 	if (ret < 0) {
 		perror("failed to write");
 		exit(-1);
 	}
 	return comm_ev.pid;
 }

 static void pid_synthesize_mmap_events(pid_t pid, pid_t pgid)
 {
 	char filename[PATH_MAX];
 	FILE *fp;

 	snprintf(filename, sizeof(filename), "/proc/%d/maps", pid);

 	fp = fopen(filename, "r");
 	if (fp == NULL) {
 		fprintf(stderr, "couldn't open %s\n", filename);
 		exit(EXIT_FAILURE);
 	}
 	while (1) {
 		char bf[BUFSIZ];
 		unsigned char vm_read, vm_write, vm_exec, vm_mayshare;
 		struct mmap_event mmap_ev = {
 			.header.type = PERF_EVENT_MMAP,
 		};
 		unsigned long ino;
 		int major, minor;
 		size_t size;
 		if (fgets(bf, sizeof(bf), fp) == NULL)
 			break;

 		/* 00400000-0040c000 r-xp 00000000 fd:01 41038  /bin/cat */
 		sscanf(bf, "%llx-%llx %c%c%c%c %llx %x:%x %lu",
 			&mmap_ev.start, &mmap_ev.len,
                         &vm_read, &vm_write, &vm_exec, &vm_mayshare,
                         &mmap_ev.pgoff, &major, &minor, &ino);
 		if (vm_exec == 'x') {
 			char *execname = strrchr(bf, ' ');

 			if (execname == NULL || execname[1] != '/')
 				continue;

 			execname += 1;
 			size = strlen(execname);
 			execname[size - 1] = '\0'; /* Remove \n */
 			memcpy(mmap_ev.filename, execname, size);
 			size = ALIGN(size, sizeof(uint64_t));
 			mmap_ev.len -= mmap_ev.start;
 			mmap_ev.header.size = (sizeof(mmap_ev) -
 					       (sizeof(mmap_ev.filename) - size));
 			mmap_ev.pid = pgid;
 			mmap_ev.tid = pid;

 			if (write(output, &mmap_ev, mmap_ev.header.size) < 0) {
 				perror("failed to write");
 				exit(-1);
 			}
 		}
 	}

 	fclose(fp);
 }

 static void open_counters(int cpu, pid_t pid)
 {
 	struct perf_counter_hw_event hw_event;
 	int counter, group_fd;
 	int track = 1;

 	if (pid > 0) {
 		pid_t pgid = pid_synthesize_comm_event(pid);
 		pid_synthesize_mmap_events(pid, pgid);
 	}

 	group_fd = -1;
 	for (counter = 0; counter < nr_counters; counter++) {

 		memset(&hw_event, 0, sizeof(hw_event));
 		hw_event.config		= event_id[counter];
 		hw_event.irq_period	= event_count[counter];
 		hw_event.record_type	= PERF_RECORD_IP | PERF_RECORD_TID;
 		hw_event.nmi		= nmi;
 		hw_event.mmap		= track;
 		hw_event.comm		= track;
 		hw_event.inherit	= (cpu < 0) && inherit;

 		track = 0; // only the first counter needs these

 		fd[nr_cpu][counter] =
 			sys_perf_counter_open(&hw_event, pid, cpu, group_fd, 0);

 		if (fd[nr_cpu][counter] < 0) {
 			int err = errno;
 			printf("kerneltop error: syscall returned with %d (%s)\n",
 					fd[nr_cpu][counter], strerror(err));
 			if (err == EPERM)
 				printf("Are you root?\n");
 			exit(-1);
 		}
 		assert(fd[nr_cpu][counter] >= 0);
 		fcntl(fd[nr_cpu][counter], F_SETFL, O_NONBLOCK);

 		/*
 		 * First counter acts as the group leader:
 		 */
 		if (group && group_fd == -1)
 			group_fd = fd[nr_cpu][counter];

 		event_array[nr_poll].fd = fd[nr_cpu][counter];
 		event_array[nr_poll].events = POLLIN;
 		nr_poll++;

 		mmap_array[nr_cpu][counter].counter = counter;
 		mmap_array[nr_cpu][counter].prev = 0;
 		mmap_array[nr_cpu][counter].mask = mmap_pages*page_size - 1;
 		mmap_array[nr_cpu][counter].base = mmap(NULL, (mmap_pages+1)*page_size,
 				PROT_READ, MAP_SHARED, fd[nr_cpu][counter], 0);
 		if (mmap_array[nr_cpu][counter].base == MAP_FAILED) {
 			printf("kerneltop error: failed to mmap with %d (%s)\n",
 					errno, strerror(errno));
 			exit(-1);
 		}
 	}
 	nr_cpu++;
 }

 static int __cmd_record(int argc, const char **argv)
 {
 	int i, counter;
 	pid_t pid;
 	int ret;

 	page_size = sysconf(_SC_PAGE_SIZE);
 	nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
 	assert(nr_cpus <= MAX_NR_CPUS);
 	assert(nr_cpus >= 0);

 	output = open(output_name, O_CREAT|O_RDWR, S_IRWXU);
 	if (output < 0) {
 		perror("failed to create output file");
 		exit(-1);
 	}

 	if (!system_wide) {
 		open_counters(-1, target_pid != -1 ? target_pid : 0);
 	} else for (i = 0; i < nr_cpus; i++)
 		open_counters(i, target_pid);

 	signal(SIGCHLD, sig_handler);
 	signal(SIGINT, sig_handler);

 	if (target_pid == -1) {
 		pid = fork();
 		if (pid < 0)
 			perror("failed to fork");

 		if (!pid) {
 			if (execvp(argv[0], (char **)argv)) {
 				perror(argv[0]);
 				exit(-1);
 			}
 		}
 	}

 	if (realtime_prio) {
 		struct sched_param param;

 		param.sched_priority = realtime_prio;
 		if (sched_setscheduler(0, SCHED_FIFO, &param)) {
 			printf("Could not set realtime priority.\n");
 			exit(-1);
 		}
 	}

 	/*
 	 * TODO: store the current /proc/$/maps information somewhere
 	 */

 	while (!done) {
 		int hits = events;

 		for (i = 0; i < nr_cpu; i++) {
 			for (counter = 0; counter < nr_counters; counter++)
 				mmap_read(&mmap_array[i][counter]);
 		}

 		if (hits == events)
 			ret = poll(event_array, nr_poll, 100);
 	}

 	return 0;
 }

 static const char * const record_usage[] = {
 	"perf record [<options>] <command>",
 	NULL
 };

 static char events_help_msg[EVENTS_HELP_MAX];

 static const struct option options[] = {
 	OPT_CALLBACK('e', "event", NULL, "event",
 		     events_help_msg, parse_events),
 	OPT_INTEGER('c', "count", &default_interval,
 		    "event period to sample"),
 	OPT_INTEGER('m', "mmap-pages", &mmap_pages,
 		    "number of mmap data pages"),
 	OPT_STRING('o', "output", &output_name, "file",
 		    "output file name"),
 	OPT_BOOLEAN('i', "inherit", &inherit,
 		    "child tasks inherit counters"),
 	OPT_INTEGER('p', "pid", &target_pid,
 		    "record events on existing pid"),
 	OPT_INTEGER('r', "realtime", &realtime_prio,
 		    "collect data with this RT SCHED_FIFO priority"),
 	OPT_BOOLEAN('a', "all-cpus", &system_wide,
 			    "system-wide collection from all CPUs"),
 	OPT_END()
 };

 int cmd_record(int argc, const char **argv, const char *prefix)
 {
 	int counter;

 	create_events_help(events_help_msg);

 	argc = parse_options(argc, argv, options, record_usage, 0);
 	if (!argc)
 		usage_with_options(record_usage, options);

 	if (!nr_counters) {
 		nr_counters = 1;
 		event_id[0] = 0;
 	}

 	for (counter = 0; counter < nr_counters; counter++) {
 		if (event_count[counter])
 			continue;

 		event_count[counter] = default_interval;
 	}

 	return __cmd_record(argc, argv);
 }


	#include "perf.h"
	#include "util/util.h"
	#include "util/parse-options.h"
	#include "util/parse-events.h"

	#include <sched.h>

	#define ALIGN(x, a) __ALIGN_MASK(x, (typeof(x))(a)-1)
	#define __ALIGN_MASK(x, mask) (((x)+(mask))&~(mask))

	static int default_interval = 100000;
	static int event_count[MAX_COUNTERS];

	static int fd[MAX_NR_CPUS][MAX_COUNTERS];
	static int nr_cpus = 0;
	static unsigned int page_size;
	static unsigned int mmap_pages = 16;
	static int output;
	static const char *output_name = "output.perf";
	static int group = 0;
	static unsigned int realtime_prio = 0;
	static int system_wide = 0;
	static pid_t target_pid = -1;
	static int inherit = 1;
	static int nmi = 1;

	const unsigned int default_count[] = {
	1000000,
	1000000,
	10000,
	10000,
	1000000,
	10000,
	};

	struct mmap_data {
	int counter;
	void *base;
	unsigned int mask;
	unsigned int prev;
	};

	static unsigned int mmap_read_head(struct mmap_data *md)
	{
	struct perf_counter_mmap_page *pc = md->base;
	int head;

	head = pc->data_head;
	rmb();

	return head;
	}

	static long events;
	static struct timeval last_read, this_read;

	static void mmap_read(struct mmap_data *md)
	{
	unsigned int head = mmap_read_head(md);
	unsigned int old = md->prev;
	unsigned char *data = md->base + page_size;
	unsigned long size;
	void *buf;
	int diff;

	gettimeofday(&this_read, NULL);

	/*
	* If we're further behind than half the buffer, there's a chance
	* the writer will bite our tail and screw up the events under us.
	*
	* If we somehow ended up ahead of the head, we got messed up.
	*
	* In either case, truncate and restart at head.
	*/
	diff = head - old;
	if (diff > md->mask / 2 \|\| diff < 0) {
	struct timeval iv;
	unsigned long msecs;

	timersub(&this_read, &last_read, &iv);
	msecs = iv.tv_sec*1000 + iv.tv_usec/1000;

	fprintf(stderr, "WARNING: failed to keep up with mmap data."
	" Last read %lu msecs ago.\n", msecs);

	/*
	* head points to a known good entry, start there.
	*/
	old = head;
	}

	last_read = this_read;

	if (old != head)
	events++;

	size = head - old;

	if ((old & md->mask) + size != (head & md->mask)) {
	buf = &data[old & md->mask];
	size = md->mask + 1 - (old & md->mask);
	old += size;
	while (size) {
	int ret = write(output, buf, size);
	if (ret < 0) {
	perror("failed to write");
	exit(-1);
	}
	size -= ret;
	buf += ret;
	}
	}

	buf = &data[old & md->mask];
	size = head - old;
	old += size;
	while (size) {
	int ret = write(output, buf, size);
	if (ret < 0) {
	perror("failed to write");
	exit(-1);
	}
	size -= ret;
	buf += ret;
	}

	md->prev = old;
	}

	static volatile int done = 0;

	static void sig_handler(int sig)
	{
	done = 1;
	}

	static struct pollfd event_array[MAX_NR_CPUS * MAX_COUNTERS];
	static struct mmap_data mmap_array[MAX_NR_CPUS][MAX_COUNTERS];

	static int nr_poll;
	static int nr_cpu;

	struct mmap_event {
	struct perf_event_header header;
	__u32 pid, tid;
	__u64 start;
	__u64 len;
	__u64 pgoff;
	char filename[PATH_MAX];
	};
	struct comm_event {
	struct perf_event_header header;
	__u32 pid,tid;
	char comm[16];
	};

	static pid_t pid_synthesize_comm_event(pid_t pid)
	{
	char filename[PATH_MAX];
	char bf[BUFSIZ];
	struct comm_event comm_ev;
	size_t size;
	int fd;

	snprintf(filename, sizeof(filename), "/proc/%d/stat", pid);

	fd = open(filename, O_RDONLY);
	if (fd < 0) {
	fprintf(stderr, "couldn't open %s\n", filename);
	exit(EXIT_FAILURE);
	}
	if (read(fd, bf, sizeof(bf)) < 0) {
	fprintf(stderr, "couldn't read %s\n", filename);
	exit(EXIT_FAILURE);
	}
	close(fd);

	pid_t spid, ppid;
	char state;
	char comm[18];

	memset(&comm_ev, 0, sizeof(comm_ev));
	int nr = sscanf(bf, "%d %s %c %d %d ",
	&spid, comm, &state, &ppid, &comm_ev.pid);
	if (nr != 5) {
	fprintf(stderr, "couldn't get COMM and pgid, malformed %s\n",
	filename);
	exit(EXIT_FAILURE);
	}
	comm_ev.header.type = PERF_EVENT_COMM;
	comm_ev.tid = pid;
	size = strlen(comm);
	comm[--size] = '\0'; /* Remove the ')' at the end */
	--size; /* Remove the '(' at the begin */
	memcpy(comm_ev.comm, comm + 1, size);
	size = ALIGN(size, sizeof(uint64_t));
	comm_ev.header.size = sizeof(comm_ev) - (sizeof(comm_ev.comm) - size);
	int ret = write(output, &comm_ev, comm_ev.header.size);
	if (ret < 0) {
	perror("failed to write");
	exit(-1);
	}
	return comm_ev.pid;
	}

	static void pid_synthesize_mmap_events(pid_t pid, pid_t pgid)
	{
	char filename[PATH_MAX];
	FILE *fp;

	snprintf(filename, sizeof(filename), "/proc/%d/maps", pid);

	fp = fopen(filename, "r");
	if (fp == NULL) {
	fprintf(stderr, "couldn't open %s\n", filename);
	exit(EXIT_FAILURE);
	}
	while (1) {
	char bf[BUFSIZ];
	unsigned char vm_read, vm_write, vm_exec, vm_mayshare;
	struct mmap_event mmap_ev = {
	.header.type = PERF_EVENT_MMAP,
	};
	unsigned long ino;
	int major, minor;
	size_t size;
	if (fgets(bf, sizeof(bf), fp) == NULL)
	break;

	/* 00400000-0040c000 r-xp 00000000 fd:01 41038 /bin/cat */
	sscanf(bf, "%llx-%llx %c%c%c%c %llx %x:%x %lu",
	&mmap_ev.start, &mmap_ev.len,
	&vm_read, &vm_write, &vm_exec, &vm_mayshare,
	&mmap_ev.pgoff, &major, &minor, &ino);
	if (vm_exec == 'x') {
	char *execname = strrchr(bf, ' ');

	if (execname == NULL \|\| execname[1] != '/')
	continue;

	execname += 1;
	size = strlen(execname);
	execname[size - 1] = '\0'; /* Remove \n */
	memcpy(mmap_ev.filename, execname, size);
	size = ALIGN(size, sizeof(uint64_t));
	mmap_ev.len -= mmap_ev.start;
	mmap_ev.header.size = (sizeof(mmap_ev) -
	(sizeof(mmap_ev.filename) - size));
	mmap_ev.pid = pgid;
	mmap_ev.tid = pid;

	if (write(output, &mmap_ev, mmap_ev.header.size) < 0) {
	perror("failed to write");
	exit(-1);
	}
	}
	}

	fclose(fp);
	}

	static void open_counters(int cpu, pid_t pid)
	{
	struct perf_counter_hw_event hw_event;
	int counter, group_fd;
	int track = 1;

	if (pid > 0) {
	pid_t pgid = pid_synthesize_comm_event(pid);
	pid_synthesize_mmap_events(pid, pgid);
	}

	group_fd = -1;
	for (counter = 0; counter < nr_counters; counter++) {

	memset(&hw_event, 0, sizeof(hw_event));
	hw_event.config = event_id[counter];
	hw_event.irq_period = event_count[counter];
	hw_event.record_type = PERF_RECORD_IP \| PERF_RECORD_TID;
	hw_event.nmi = nmi;
	hw_event.mmap = track;
	hw_event.comm = track;
	hw_event.inherit = (cpu < 0) && inherit;

	track = 0; // only the first counter needs these

	fd[nr_cpu][counter] =
	sys_perf_counter_open(&hw_event, pid, cpu, group_fd, 0);

	if (fd[nr_cpu][counter] < 0) {
	int err = errno;
	printf("kerneltop error: syscall returned with %d (%s)\n",
	fd[nr_cpu][counter], strerror(err));
	if (err == EPERM)
	printf("Are you root?\n");
	exit(-1);
	}
	assert(fd[nr_cpu][counter] >= 0);
	fcntl(fd[nr_cpu][counter], F_SETFL, O_NONBLOCK);

	/*
	* First counter acts as the group leader:
	*/
	if (group && group_fd == -1)
	group_fd = fd[nr_cpu][counter];

	event_array[nr_poll].fd = fd[nr_cpu][counter];
	event_array[nr_poll].events = POLLIN;
	nr_poll++;

	mmap_array[nr_cpu][counter].counter = counter;
	mmap_array[nr_cpu][counter].prev = 0;
	mmap_array[nr_cpu][counter].mask = mmap_pages*page_size - 1;
	mmap_array[nr_cpu][counter].base = mmap(NULL, (mmap_pages+1)*page_size,
	PROT_READ, MAP_SHARED, fd[nr_cpu][counter], 0);
	if (mmap_array[nr_cpu][counter].base == MAP_FAILED) {
	printf("kerneltop error: failed to mmap with %d (%s)\n",
	errno, strerror(errno));
	exit(-1);
	}
	}
	nr_cpu++;
	}

	static int __cmd_record(int argc, const char **argv)
	{
	int i, counter;
	pid_t pid;
	int ret;

	page_size = sysconf(_SC_PAGE_SIZE);
	nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
	assert(nr_cpus <= MAX_NR_CPUS);
	assert(nr_cpus >= 0);

	output = open(output_name, O_CREAT\|O_RDWR, S_IRWXU);
	if (output < 0) {
	perror("failed to create output file");
	exit(-1);
	}

	if (!system_wide) {
	open_counters(-1, target_pid != -1 ? target_pid : 0);
	} else for (i = 0; i < nr_cpus; i++)
	open_counters(i, target_pid);

	signal(SIGCHLD, sig_handler);
	signal(SIGINT, sig_handler);

	if (target_pid == -1) {
	pid = fork();
	if (pid < 0)
	perror("failed to fork");

	if (!pid) {
	if (execvp(argv[0], (char **)argv)) {
	perror(argv[0]);
	exit(-1);
	}
	}
	}

	if (realtime_prio) {
	struct sched_param param;

	param.sched_priority = realtime_prio;
	if (sched_setscheduler(0, SCHED_FIFO, &param)) {
	printf("Could not set realtime priority.\n");
	exit(-1);
	}
	}

	/*
	* TODO: store the current /proc/$/maps information somewhere
	*/

	while (!done) {
	int hits = events;

	for (i = 0; i < nr_cpu; i++) {
	for (counter = 0; counter < nr_counters; counter++)
	mmap_read(&mmap_array[i][counter]);
	}

	if (hits == events)
	ret = poll(event_array, nr_poll, 100);
	}

	return 0;
	}

	static const char * const record_usage[] = {
	"perf record [<options>] <command>",
	NULL
	};

	static char events_help_msg[EVENTS_HELP_MAX];

	static const struct option options[] = {
	OPT_CALLBACK('e', "event", NULL, "event",
	events_help_msg, parse_events),
	OPT_INTEGER('c', "count", &default_interval,
	"event period to sample"),
	OPT_INTEGER('m', "mmap-pages", &mmap_pages,
	"number of mmap data pages"),
	OPT_STRING('o', "output", &output_name, "file",
	"output file name"),
	OPT_BOOLEAN('i', "inherit", &inherit,
	"child tasks inherit counters"),
	OPT_INTEGER('p', "pid", &target_pid,
	"record events on existing pid"),
	OPT_INTEGER('r', "realtime", &realtime_prio,
	"collect data with this RT SCHED_FIFO priority"),
	OPT_BOOLEAN('a', "all-cpus", &system_wide,
	"system-wide collection from all CPUs"),
	OPT_END()
	};

	int cmd_record(int argc, const char *argv, const char prefix)
	{
	int counter;

	create_events_help(events_help_msg);

	argc = parse_options(argc, argv, options, record_usage, 0);
	if (!argc)
	usage_with_options(record_usage, options);

	if (!nr_counters) {
	nr_counters = 1;
	event_id[0] = 0;
	}

	for (counter = 0; counter < nr_counters; counter++) {
	if (event_count[counter])
	continue;

	event_count[counter] = default_interval;
	}

	return __cmd_record(argc, argv);
	}