path: root/tools/perf/util/event.c

#include <linux/types.h>
#include "event.h"
#include "debug.h"
#include "sort.h"
#include "string.h"
#include "strlist.h"
#include "thread.h"
#include "thread_map.h"

static const char *perf_event__names[] = {
	[0]					= "TOTAL",
	[PERF_RECORD_MMAP]			= "MMAP",
	[PERF_RECORD_LOST]			= "LOST",
	[PERF_RECORD_COMM]			= "COMM",
	[PERF_RECORD_EXIT]			= "EXIT",
	[PERF_RECORD_THROTTLE]			= "THROTTLE",
	[PERF_RECORD_UNTHROTTLE]		= "UNTHROTTLE",
	[PERF_RECORD_FORK]			= "FORK",
	[PERF_RECORD_READ]			= "READ",
	[PERF_RECORD_SAMPLE]			= "SAMPLE",
	[PERF_RECORD_HEADER_ATTR]		= "ATTR",
	[PERF_RECORD_HEADER_EVENT_TYPE]		= "EVENT_TYPE",
	[PERF_RECORD_HEADER_TRACING_DATA]	= "TRACING_DATA",
	[PERF_RECORD_HEADER_BUILD_ID]		= "BUILD_ID",
	[PERF_RECORD_FINISHED_ROUND]		= "FINISHED_ROUND",
};

const char *perf_event__name(unsigned int id)
{
	if (id >= ARRAY_SIZE(perf_event__names))
		return "INVALID";
	if (!perf_event__names[id])
		return "UNKNOWN";
	return perf_event__names[id];
}

static struct perf_sample synth_sample = {
	.pid	   = -1,
	.tid	   = -1,
	.time	   = -1,
	.stream_id = -1,
	.cpu	   = -1,
	.period	   = 1,
};

static pid_t perf_event__get_comm_tgid(pid_t pid, char *comm, size_t len)
{
	char filename[PATH_MAX];
	char bf[BUFSIZ];
	FILE *fp;
	size_t size = 0;
	pid_t tgid = -1;

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

	fp = fopen(filename, "r");
	if (fp == NULL) {
		pr_debug("couldn't open %s\n", filename);
		return 0;
	}

	while (!comm[0] || (tgid < 0)) {
		if (fgets(bf, sizeof(bf), fp) == NULL) {
			pr_warning("couldn't get COMM and pgid, malformed %s\n",
				   filename);
			break;
		}

		if (memcmp(bf, "Name:", 5) == 0) {
			char *name = bf + 5;
			while (*name && isspace(*name))
				++name;
			size = strlen(name) - 1;
			if (size >= len)
				size = len - 1;
			memcpy(comm, name, size);
			comm[size] = '\0';

		} else if (memcmp(bf, "Tgid:", 5) == 0) {
			char *tgids = bf + 5;
			while (*tgids && isspace(*tgids))
				++tgids;
			tgid = atoi(tgids);
		}
	}

	fclose(fp);

	return tgid;
}

static pid_t perf_event__synthesize_comm(struct perf_tool *tool,
					 union perf_event *event, pid_t pid,
					 int full,
					 perf_event__handler_t process,
					 struct machine *machine)
{
	char filename[PATH_MAX];
	size_t size;
	DIR *tasks;
	struct dirent dirent, *next;
	pid_t tgid;

	memset(&event->comm, 0, sizeof(event->comm));

	tgid = perf_event__get_comm_tgid(pid, event->comm.comm,
					 sizeof(event->comm.comm));
	if (tgid < 0)
		goto out;

	event->comm.pid = tgid;
	event->comm.header.type = PERF_RECORD_COMM;

	size = strlen(event->comm.comm) + 1;
	size = ALIGN(size, sizeof(u64));
	memset(event->comm.comm + size, 0, machine->id_hdr_size);
	event->comm.header.size = (sizeof(event->comm) -
				(sizeof(event->comm.comm) - size) +
				machine->id_hdr_size);
	if (!full) {
		event->comm.tid = pid;

		process(tool, event, &synth_sample, machine);
		goto out;
	}

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

	tasks = opendir(filename);
	if (tasks == NULL) {
		pr_debug("couldn't open %s\n", filename);
		return 0;
	}

	while (!readdir_r(tasks, &dirent, &next) && next) {