perf_counter tools: Move from Documentation/perf_counter/ to tools/perf/

Several people have suggested that 'perf' has become a full-fledged
tool that should be moved out of Documentation/. Move it to the
(new) tools/ directory.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 544 insertions, 0 deletions

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
new file mode 100644
index 0000000..aeab9c4
--- /dev/null
+++ b/tools/perf/builtin-record.c
@@ -0,0 +1,544 @@
+/*
+ * builtin-record.c
+ *
+ * Builtin record command: Record the profile of a workload
+ * (or a CPU, or a PID) into the perf.data output file - for
+ * later analysis via perf report.
+ */
+#include "builtin.h"
+
+#include "perf.h"
+
+#include "util/util.h"
+#include "util/parse-options.h"
+#include "util/parse-events.h"
+#include "util/string.h"
+
+#include <unistd.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			fd[MAX_NR_CPUS][MAX_COUNTERS];
+
+static long			default_interval		= 100000;
+
+static int			nr_cpus				= 0;
+static unsigned int		page_size;
+static unsigned int		mmap_pages			= 128;
+static int			freq				= 0;
+static int			output;
+static const char		*output_name			= "perf.data";
+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			force				= 0;
+static int			append_file			= 0;
+
+static long			samples;
+static struct timeval		last_read;
+static struct timeval		this_read;
+
+static __u64			bytes_written;
+
+static struct pollfd		event_array[MAX_NR_CPUS * MAX_COUNTERS];
+
+static int			nr_poll;
+static int			nr_cpu;
+
+struct mmap_event {
+	struct perf_event_header	header;
+	__u32				pid;
+	__u32				tid;
+	__u64				start;
+	__u64				len;
+	__u64				pgoff;
+	char				filename[PATH_MAX];
+};
+
+struct comm_event {
+	struct perf_event_header	header;
+	__u32				pid;
+	__u32				tid;
+	char				comm[16];
+};
+
+
+struct mmap_data {
+	int			counter;
+	void			*base;
+	unsigned int		mask;
+	unsigned int		prev;
+};
+
+static struct mmap_data		mmap_array[MAX_NR_CPUS][MAX_COUNTERS];
+
+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 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 mess up the samples 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)
+		samples++;
+
+	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)
+				die("failed to write");
+
+			size -= ret;
+			buf += ret;
+
+			bytes_written += ret;
+		}
+	}
+
+	buf = &data[old & md->mask];
+	size = head - old;
+	old += size;
+
+	while (size) {
+		int ret = write(output, buf, size);
+
+		if (ret < 0)
+			die("failed to write");
+
+		size -= ret;
+		buf += ret;
+
+		bytes_written += ret;
+	}
+
+	md->prev = old;
+}
+
+static volatile int done = 0;
+
+static void sig_handler(int sig)
+{
+	done = 1;
+}
+
+static void pid_synthesize_comm_event(pid_t pid, int full)
+{
+	struct comm_event comm_ev;
+	char filename[PATH_MAX];
+	char bf[BUFSIZ];
+	int fd, ret;
+	size_t size;
+	char *field, *sep;
+	DIR *tasks;
+	struct dirent dirent, *next;
+
+	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);
+
+	/* 9027 (cat) R 6747 9027 6747 34816 9027 ... */
+	memset(&comm_ev, 0, sizeof(comm_ev));
+	field = strchr(bf, '(');
+	if (field == NULL)
+		goto out_failure;
+	sep = strchr(++field, ')');
+	if (sep == NULL)
+		goto out_failure;
+	size = sep - field;
+	memcpy(comm_ev.comm, field, size++);
+
+	comm_ev.pid = pid;
+	comm_ev.header.type = PERF_EVENT_COMM;
+	size = ALIGN(size, sizeof(uint64_t));
+	comm_ev.header.size = sizeof(comm_ev) - (sizeof(comm_ev.comm) - size);
+
+	if (!full) {
+		comm_ev.tid = pid;
+
+		ret = write(output, &comm_ev, comm_ev.header.size);
+		if (ret < 0) {
+			perror("failed to write");
+			exit(-1);
+		}
+		return;
+	}
+
+	snprintf(filename, sizeof(filename), "/proc/%d/task", pid);
+
+	tasks = opendir(filename);
+	while (!readdir_r(tasks, &dirent, &next) && next) {
+		char *end;
+		pid = strtol(dirent.d_name, &end, 10);
+		if (*end)
+			continue;
+
+		comm_ev.tid = pid;
+
+		ret = write(output, &comm_ev, comm_ev.header.size);
+		if (ret < 0) {
+			perror("failed to write");
+			exit(-1);
+		}
+	}
+	closedir(tasks);
+	return;
+
+out_failure:
+	fprintf(stderr, "couldn't get COMM and pgid, malformed %s\n",
+		filename);
+	exit(EXIT_FAILURE);
+}
+
+static void pid_synthesize_mmap_samples(pid_t pid)
+{
+	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], *pbf = bf;
+		struct mmap_event mmap_ev = {
+			.header.type = PERF_EVENT_MMAP,
+		};
+		int n;
+		size_t size;
+		if (fgets(bf, sizeof(bf), fp) == NULL)
+			break;
+
+		/* 00400000-0040c000 r-xp 00000000 fd:01 41038  /bin/cat */
+		n = hex2u64(pbf, &mmap_ev.start);
+		if (n < 0)
+			continue;
+		pbf += n + 1;
+		n = hex2u64(pbf, &mmap_ev.len);
+		if (n < 0)
+			continue;
+		pbf += n + 3;
+		if (*pbf == 'x') { /* vm_exec */
+			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 = pid;
+			mmap_ev.tid = pid;
+
+			if (write(output, &mmap_ev, mmap_ev.header.size) < 0) {
+				perror("failed to write");
+				exit(-1);
+			}
+		}
+	}
+
+	fclose(fp);
+}
+
+static void synthesize_samples(void)
+{
+	DIR *proc;
+	struct dirent dirent, *next;
+
+	proc = opendir("/proc");
+
+	while (!readdir_r(proc, &dirent, &next) && next) {
+		char *end;
+		pid_t pid;
+
+		pid = strtol(dirent.d_name, &end, 10);
+		if (*end) /* only interested in proper numerical dirents */
+			continue;
+
+		pid_synthesize_comm_event(pid, 1);
+		pid_synthesize_mmap_samples(pid);
+	}
+
+	closedir(proc);
+}
+
+static int group_fd;
+
+static void create_counter(int counter, int cpu, pid_t pid)
+{
+	struct perf_counter_attr *attr = attrs + counter;
+	int track = 1;
+
+	attr->sample_type	= PERF_SAMPLE_IP | PERF_SAMPLE_TID | PERF_SAMPLE_PERIOD;
+	if (freq) {
+		attr->freq		= 1;
+		attr->sample_freq	= freq;
+	}
+	attr->mmap		= track;
+	attr->comm		= track;
+	attr->inherit		= (cpu < 0) && inherit;
+
+	track = 0; /* only the first counter needs these */
+
+	fd[nr_cpu][counter] = sys_perf_counter_open(attr, pid, cpu, group_fd, 0);
+
+	if (fd[nr_cpu][counter] < 0) {
+		int err = errno;
+
+		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) {
+		error("failed to mmap with %d (%s)\n", errno, strerror(errno));
+		exit(-1);
+	}
+}
+
+static void open_counters(int cpu, pid_t pid)
+{
+	int counter;
+
+	if (pid > 0) {
+		pid_synthesize_comm_event(pid, 0);
+		pid_synthesize_mmap_samples(pid);
+	}
+
+	group_fd = -1;
+	for (counter = 0; counter < nr_counters; counter++)
+		create_counter(counter, cpu, pid);
+
+	nr_cpu++;
+}
+
+static int __cmd_record(int argc, const char **argv)
+{
+	int i, counter;
+	struct stat st;
+	pid_t pid;
+	int flags;
+	int ret;
+
+	page_size = sysconf(_SC_PAGE_SIZE);
+	nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
+	assert(nr_cpus <= MAX_NR_CPUS);
+	assert(nr_cpus >= 0);
+
+	if (!stat(output_name, &st) && !force && !append_file) {
+		fprintf(stderr, "Error, output file %s exists, use -A to append or -f to overwrite.\n",
+				output_name);
+		exit(-1);
+	}
+
+	flags = O_CREAT|O_RDWR;
+	if (append_file)
+		flags |= O_APPEND;
+	else
+		flags |= O_TRUNC;
+
+	output = open(output_name, flags, S_IRUSR|S_IWUSR);
+	if (output < 0) {
+		perror("failed to create output file");
+		exit(-1);
+	}
+
+	if (!system_wide) {
+		open_counters(-1, target_pid != -1 ? target_pid : getpid());
+	} 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 && argc) {
+		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);
+		}
+	}
+
+	if (system_wide)
+		synthesize_samples();
+
+	while (!done) {
+		int hits = samples;
+
+		for (i = 0; i < nr_cpu; i++) {
+			for (counter = 0; counter < nr_counters; counter++)
+				mmap_read(&mmap_array[i][counter]);
+		}
+
+		if (hits == samples)
+			ret = poll(event_array, nr_poll, 100);
+	}
+
+	/*
+	 * Approximate RIP event size: 24 bytes.
+	 */
+	fprintf(stderr,
+		"[ perf record: Captured and wrote %.3f MB %s (~%lld samples) ]\n",
+		(double)bytes_written / 1024.0 / 1024.0,
+		output_name,
+		bytes_written / 24);
+
+	return 0;
+}
+
+static const char * const record_usage[] = {
+	"perf record [<options>] [<command>]",
+	"perf record [<options>] -- <command> [<options>]",
+	NULL
+};
+
+static const struct option options[] = {
+	OPT_CALLBACK('e', "event", NULL, "event",
+		     "event selector. use 'perf list' to list available events",
+		     parse_events),
+	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_BOOLEAN('A', "append", &append_file,
+			    "append to the output file to do incremental profiling"),
+	OPT_BOOLEAN('f', "force", &force,
+			"overwrite existing data file"),
+	OPT_LONG('c', "count", &default_interval,
+		    "event period to sample"),
+	OPT_STRING('o', "output", &output_name, "file",
+		    "output file name"),
+	OPT_BOOLEAN('i', "inherit", &inherit,
+		    "child tasks inherit counters"),
+	OPT_INTEGER('F', "freq", &freq,
+		    "profile at this frequency"),
+	OPT_INTEGER('m', "mmap-pages", &mmap_pages,
+		    "number of mmap data pages"),
+	OPT_END()
+};
+
+int cmd_record(int argc, const char **argv, const char *prefix)
+{
+	int counter;
+
+	argc = parse_options(argc, argv, options, record_usage, 0);
+	if (!argc && target_pid == -1 && !system_wide)
+		usage_with_options(record_usage, options);
+
+	if (!nr_counters)
+		nr_counters = 1;
+
+	for (counter = 0; counter < nr_counters; counter++) {
+		if (attrs[counter].sample_period)
+			continue;
+
+		attrs[counter].sample_period = default_interval;
+	}
+
+	return __cmd_record(argc, argv);
+}