[linux-2.6-block.git] / Documentation / perf_counter / builtin-record.c



#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);
}
Commit	Line	Data
de9ac07b PZ	1
de9ac07b PZ	2
1a482f38	3	#include "perf.h"
6eda5838	4	#include "util/util.h"
0e9b20b8	5	#include "util/parse-options.h"
8ad8db37	6	#include "util/parse-events.h"
6eda5838	7
de9ac07b	8	#include <sched.h>
de9ac07b	9
0e9b20b8 IM	10	#define ALIGN(x, a) __ALIGN_MASK(x, (typeof(x))(a)-1)
0e9b20b8 IM	11	#define __ALIGN_MASK(x, mask) (((x)+(mask))&~(mask))
1a853e36	12
de9ac07b PZ	13	static int default_interval = 100000;
de9ac07b PZ	14	static int event_count[MAX_COUNTERS];
8ad8db37	15
de9ac07b PZ	16	static int fd[MAX_NR_CPUS][MAX_COUNTERS];
	17	static int nr_cpus = 0;
	18	static unsigned int page_size;
	19	static unsigned int mmap_pages = 16;
	20	static int output;
0e9b20b8	21	static const char *output_name = "output.perf";
de9ac07b	22	static int group = 0;
16c8a109 PZ	23	static unsigned int realtime_prio = 0;
16c8a109 PZ	24	static int system_wide = 0;
1a853e36	25	static pid_t target_pid = -1;
16c8a109 PZ	26	static int inherit = 1;
16c8a109 PZ	27	static int nmi = 1;
de9ac07b PZ	28
	29	const unsigned int default_count[] = {
	30	1000000,
	31	1000000,
	32	10000,
	33	10000,
	34	1000000,
	35	10000,
	36	};
	37
de9ac07b PZ	38	struct mmap_data {
	39	int counter;
	40	void *base;
	41	unsigned int mask;
	42	unsigned int prev;
	43	};
	44
	45	static unsigned int mmap_read_head(struct mmap_data *md)
	46	{
	47	struct perf_counter_mmap_page *pc = md->base;
	48	int head;
	49
	50	head = pc->data_head;
	51	rmb();
	52
	53	return head;
	54	}
	55
	56	static long events;
	57	static struct timeval last_read, this_read;
	58
	59	static void mmap_read(struct mmap_data *md)
	60	{
	61	unsigned int head = mmap_read_head(md);
	62	unsigned int old = md->prev;
	63	unsigned char *data = md->base + page_size;
	64	unsigned long size;
	65	void *buf;
	66	int diff;
	67
	68	gettimeofday(&this_read, NULL);
	69
	70	/*
	71	* If we're further behind than half the buffer, there's a chance
	72	* the writer will bite our tail and screw up the events under us.
	73	*
	74	* If we somehow ended up ahead of the head, we got messed up.
	75	*
	76	* In either case, truncate and restart at head.
	77	*/
	78	diff = head - old;
	79	if (diff > md->mask / 2 \|\| diff < 0) {
	80	struct timeval iv;
	81	unsigned long msecs;
	82
	83	timersub(&this_read, &last_read, &iv);
	84	msecs = iv.tv_sec*1000 + iv.tv_usec/1000;
	85
	86	fprintf(stderr, "WARNING: failed to keep up with mmap data."
	87	" Last read %lu msecs ago.\n", msecs);
	88
	89	/*
	90	* head points to a known good entry, start there.
	91	*/
	92	old = head;
	93	}
	94
	95	last_read = this_read;
	96
	97	if (old != head)
	98	events++;
	99
	100	size = head - old;
	101
102	if ((old & md->mask) + size != (head & md->mask)) {
103	buf = &data[old & md->mask];
104	size = md->mask + 1 - (old & md->mask);
105	old += size;
106	while (size) {
107	int ret = write(output, buf, size);
108	if (ret < 0) {
109	perror("failed to write");
110	exit(-1);
111	}
112	size -= ret;
113	buf += ret;
114	}
115	}
116
117	buf = &data[old & md->mask];
118	size = head - old;
119	old += size;
120	while (size) {
121	int ret = write(output, buf, size);
122	if (ret < 0) {
123	perror("failed to write");
124	exit(-1);
125	}
126	size -= ret;
127	buf += ret;
128	}
129
130	md->prev = old;
131	}
132
133	static volatile int done = 0;
134
16c8a109	135	static void sig_handler(int sig)
de9ac07b	136	{
16c8a109	137	done = 1;
de9ac07b PZ	138	}
de9ac07b PZ	139
16c8a109 PZ	140	static struct pollfd event_array[MAX_NR_CPUS * MAX_COUNTERS];
	141	static struct mmap_data mmap_array[MAX_NR_CPUS][MAX_COUNTERS];
	142
	143	static int nr_poll;
	144	static int nr_cpu;
	145
1a853e36 ACM	146	struct mmap_event {
	147	struct perf_event_header header;
	148	__u32 pid, tid;
	149	__u64 start;
	150	__u64 len;
	151	__u64 pgoff;
	152	char filename[PATH_MAX];
	153	};
	154	struct comm_event {
	155	struct perf_event_header header;
	156	__u32 pid,tid;
	157	char comm[16];
	158	};
	159
	160	static pid_t pid_synthesize_comm_event(pid_t pid)
	161	{
	162	char filename[PATH_MAX];
	163	char bf[BUFSIZ];
	164	struct comm_event comm_ev;
	165	size_t size;
	166	int fd;
	167
	168	snprintf(filename, sizeof(filename), "/proc/%d/stat", pid);
	169
	170	fd = open(filename, O_RDONLY);
	171	if (fd < 0) {
	172	fprintf(stderr, "couldn't open %s\n", filename);
	173	exit(EXIT_FAILURE);
	174	}
	175	if (read(fd, bf, sizeof(bf)) < 0) {
	176	fprintf(stderr, "couldn't read %s\n", filename);
	177	exit(EXIT_FAILURE);
	178	}
	179	close(fd);
	180
	181	pid_t spid, ppid;
	182	char state;
	183	char comm[18];
	184
	185	memset(&comm_ev, 0, sizeof(comm_ev));
	186	int nr = sscanf(bf, "%d %s %c %d %d ",
	187	&spid, comm, &state, &ppid, &comm_ev.pid);
	188	if (nr != 5) {
	189	fprintf(stderr, "couldn't get COMM and pgid, malformed %s\n",
	190	filename);
	191	exit(EXIT_FAILURE);
	192	}
	193	comm_ev.header.type = PERF_EVENT_COMM;
	194	comm_ev.tid = pid;
	195	size = strlen(comm);
	196	comm[--size] = '\0'; /* Remove the ')' at the end */
	197	--size; /* Remove the '(' at the begin */
	198	memcpy(comm_ev.comm, comm + 1, size);
	199	size = ALIGN(size, sizeof(uint64_t));
	200	comm_ev.header.size = sizeof(comm_ev) - (sizeof(comm_ev.comm) - size);
	201	int ret = write(output, &comm_ev, comm_ev.header.size);
	202	if (ret < 0) {
	203	perror("failed to write");
	204	exit(-1);
	205	}
	206	return comm_ev.pid;
	207	}
	208
	209	static void pid_synthesize_mmap_events(pid_t pid, pid_t pgid)
210	{
211	char filename[PATH_MAX];
212	FILE *fp;
213
214	snprintf(filename, sizeof(filename), "/proc/%d/maps", pid);
215
216	fp = fopen(filename, "r");
217	if (fp == NULL) {
218	fprintf(stderr, "couldn't open %s\n", filename);
219	exit(EXIT_FAILURE);
220	}
221	while (1) {
222	char bf[BUFSIZ];
223	unsigned char vm_read, vm_write, vm_exec, vm_mayshare;
224	struct mmap_event mmap_ev = {
225	.header.type = PERF_EVENT_MMAP,
226	};
227	unsigned long ino;
228	int major, minor;
229	size_t size;
230	if (fgets(bf, sizeof(bf), fp) == NULL)
231	break;
232
233	/* 00400000-0040c000 r-xp 00000000 fd:01 41038 /bin/cat */
234	sscanf(bf, "%llx-%llx %c%c%c%c %llx %x:%x %lu",
235	&mmap_ev.start, &mmap_ev.len,
236	&vm_read, &vm_write, &vm_exec, &vm_mayshare,
237	&mmap_ev.pgoff, &major, &minor, &ino);
238	if (vm_exec == 'x') {
239	char *execname = strrchr(bf, ' ');
240
241	if (execname == NULL \|\| execname[1] != '/')
242	continue;
243
244	execname += 1;
245	size = strlen(execname);
246	execname[size - 1] = '\0'; /* Remove \n */
247	memcpy(mmap_ev.filename, execname, size);
248	size = ALIGN(size, sizeof(uint64_t));
249	mmap_ev.len -= mmap_ev.start;
250	mmap_ev.header.size = (sizeof(mmap_ev) -
251	(sizeof(mmap_ev.filename) - size));
252	mmap_ev.pid = pgid;
253	mmap_ev.tid = pid;
254
255	if (write(output, &mmap_ev, mmap_ev.header.size) < 0) {
256	perror("failed to write");
257	exit(-1);
258	}
259	}
260	}
261
262	fclose(fp);
263	}
264
265	static void open_counters(int cpu, pid_t pid)
de9ac07b	266	{
de9ac07b	267	struct perf_counter_hw_event hw_event;
16c8a109 PZ	268	int counter, group_fd;
16c8a109 PZ	269	int track = 1;
16c8a109	270
1a853e36 ACM	271	if (pid > 0) {
	272	pid_t pgid = pid_synthesize_comm_event(pid);
	273	pid_synthesize_mmap_events(pid, pgid);
	274	}
16c8a109 PZ	275
	276	group_fd = -1;
	277	for (counter = 0; counter < nr_counters; counter++) {
	278
	279	memset(&hw_event, 0, sizeof(hw_event));
	280	hw_event.config = event_id[counter];
	281	hw_event.irq_period = event_count[counter];
	282	hw_event.record_type = PERF_RECORD_IP \| PERF_RECORD_TID;
	283	hw_event.nmi = nmi;
	284	hw_event.mmap = track;
	285	hw_event.comm = track;
	286	hw_event.inherit = (cpu < 0) && inherit;
	287
	288	track = 0; // only the first counter needs these
	289
	290	fd[nr_cpu][counter] =
	291	sys_perf_counter_open(&hw_event, pid, cpu, group_fd, 0);
	292
	293	if (fd[nr_cpu][counter] < 0) {
	294	int err = errno;
	295	printf("kerneltop error: syscall returned with %d (%s)\n",
	296	fd[nr_cpu][counter], strerror(err));
	297	if (err == EPERM)
	298	printf("Are you root?\n");
	299	exit(-1);
	300	}
	301	assert(fd[nr_cpu][counter] >= 0);
	302	fcntl(fd[nr_cpu][counter], F_SETFL, O_NONBLOCK);
	303
	304	/*
	305	* First counter acts as the group leader:
	306	*/
	307	if (group && group_fd == -1)
	308	group_fd = fd[nr_cpu][counter];
	309
	310	event_array[nr_poll].fd = fd[nr_cpu][counter];
	311	event_array[nr_poll].events = POLLIN;
	312	nr_poll++;
	313
	314	mmap_array[nr_cpu][counter].counter = counter;
	315	mmap_array[nr_cpu][counter].prev = 0;
	316	mmap_array[nr_cpu][counter].mask = mmap_pages*page_size - 1;
	317	mmap_array[nr_cpu][counter].base = mmap(NULL, (mmap_pages+1)*page_size,
	318	PROT_READ, MAP_SHARED, fd[nr_cpu][counter], 0);
	319	if (mmap_array[nr_cpu][counter].base == MAP_FAILED) {
	320	printf("kerneltop error: failed to mmap with %d (%s)\n",
	321	errno, strerror(errno));
	322	exit(-1);
	323	}
	324	}
	325	nr_cpu++;
	326	}
	327
0e9b20b8	328	static int __cmd_record(int argc, const char **argv)
16c8a109 PZ	329	{
16c8a109 PZ	330	int i, counter;
de9ac07b PZ	331	pid_t pid;
	332	int ret;
	333
	334	page_size = sysconf(_SC_PAGE_SIZE);
de9ac07b PZ	335	nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
	336	assert(nr_cpus <= MAX_NR_CPUS);
	337	assert(nr_cpus >= 0);
	338
	339	output = open(output_name, O_CREAT\|O_RDWR, S_IRWXU);
	340	if (output < 0) {
	341	perror("failed to create output file");
	342	exit(-1);
	343	}
	344
1a853e36 ACM	345	if (!system_wide) {
	346	open_counters(-1, target_pid != -1 ? target_pid : 0);
	347	} else for (i = 0; i < nr_cpus; i++)
	348	open_counters(i, target_pid);
de9ac07b	349
16c8a109 PZ	350	signal(SIGCHLD, sig_handler);
16c8a109 PZ	351	signal(SIGINT, sig_handler);
de9ac07b	352
1a853e36 ACM	353	if (target_pid == -1) {
	354	pid = fork();
	355	if (pid < 0)
	356	perror("failed to fork");
de9ac07b	357
1a853e36	358	if (!pid) {
0e9b20b8	359	if (execvp(argv[0], (char **)argv)) {
1a853e36 ACM	360	perror(argv[0]);
	361	exit(-1);
	362	}
de9ac07b PZ	363	}
	364	}
	365
	366	if (realtime_prio) {
	367	struct sched_param param;
	368
	369	param.sched_priority = realtime_prio;
	370	if (sched_setscheduler(0, SCHED_FIFO, &param)) {
	371	printf("Could not set realtime priority.\n");
	372	exit(-1);
	373	}
	374	}
	375
	376	/*
	377	* TODO: store the current /proc/$/maps information somewhere
	378	*/
	379
	380	while (!done) {
	381	int hits = events;
	382
16c8a109	383	for (i = 0; i < nr_cpu; i++) {
de9ac07b PZ	384	for (counter = 0; counter < nr_counters; counter++)
	385	mmap_read(&mmap_array[i][counter]);
	386	}
	387
	388	if (hits == events)
	389	ret = poll(event_array, nr_poll, 100);
	390	}
	391
	392	return 0;
	393	}
0e9b20b8	394
0e9b20b8 IM	395	static const char * const record_usage[] = {
	396	"perf record [<options>] <command>",
	397	NULL
	398	};
	399
8ad8db37 IM	400	static char events_help_msg[EVENTS_HELP_MAX];
8ad8db37 IM	401
5242519b	402	static const struct option options[] = {
0e9b20b8	403	OPT_CALLBACK('e', "event", NULL, "event",
8ad8db37	404	events_help_msg, parse_events),
0e9b20b8 IM	405	OPT_INTEGER('c', "count", &default_interval,
	406	"event period to sample"),
	407	OPT_INTEGER('m', "mmap-pages", &mmap_pages,
	408	"number of mmap data pages"),
	409	OPT_STRING('o', "output", &output_name, "file",
	410	"output file name"),
	411	OPT_BOOLEAN('i', "inherit", &inherit,
	412	"child tasks inherit counters"),
	413	OPT_INTEGER('p', "pid", &target_pid,
	414	"record events on existing pid"),
	415	OPT_INTEGER('r', "realtime", &realtime_prio,
	416	"collect data with this RT SCHED_FIFO priority"),
	417	OPT_BOOLEAN('a', "all-cpus", &system_wide,
	418	"system-wide collection from all CPUs"),
	419	OPT_END()
	420	};
	421
	422	int cmd_record(int argc, const char *argv, const char prefix)
	423	{
	424	int counter;
	425
8ad8db37	426	create_events_help(events_help_msg);
0e9b20b8 IM	427
	428	argc = parse_options(argc, argv, options, record_usage, 0);
	429	if (!argc)
	430	usage_with_options(record_usage, options);
	431
	432	if (!nr_counters) {
	433	nr_counters = 1;
	434	event_id[0] = 0;
	435	}
	436
	437	for (counter = 0; counter < nr_counters; counter++) {
	438	if (event_count[counter])
	439	continue;
	440
	441	event_count[counter] = default_interval;
	442	}
	443
	444	return __cmd_record(argc, argv);
	445	}