path: root/tools/perf/builtin-record.c

/*
 * 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/build-id.h"
#include "util/util.h"
#include "util/parse-options.h"
#include "util/parse-events.h"

#include "util/header.h"
#include "util/event.h"
#include "util/evlist.h"
#include "util/evsel.h"
#include "util/debug.h"
#include "util/session.h"
#include "util/tool.h"
#include "util/symbol.h"
#include "util/cpumap.h"
#include "util/thread_map.h"
#include "util/data.h"

#include <unistd.h>
#include <sched.h>
#include <sys/mman.h>

#ifndef HAVE_ON_EXIT_SUPPORT
#ifndef ATEXIT_MAX
#define ATEXIT_MAX 32
#endif
static int __on_exit_count = 0;
typedef void (*on_exit_func_t) (int, void *);
static on_exit_func_t __on_exit_funcs[ATEXIT_MAX];
static void *__on_exit_args[ATEXIT_MAX];
static int __exitcode = 0;
static void __handle_on_exit_funcs(void);
static int on_exit(on_exit_func_t function, void *arg);
#define exit(x) (exit)(__exitcode = (x))

static int on_exit(on_exit_func_t function, void *arg)
{
	if (__on_exit_count == ATEXIT_MAX)
		return -ENOMEM;
	else if (__on_exit_count == 0)
		atexit(__handle_on_exit_funcs);
	__on_exit_funcs[__on_exit_count] = function;
	__on_exit_args[__on_exit_count++] = arg;
	return 0;
}

static void __handle_on_exit_funcs(void)
{
	int i;
	for (i = 0; i < __on_exit_count; i++)
		__on_exit_funcs[i] (__exitcode, __on_exit_args[i]);
}
#endif

struct perf_record {
	struct perf_tool	tool;
	struct perf_record_opts	opts;
	u64			bytes_written;
	struct perf_data_file	file;
	struct perf_evlist	*evlist;
	struct perf_session	*session;
	const char		*progname;
	int			realtime_prio;
	bool			no_buildid;
	bool			no_buildid_cache;
	long			samples;
};

static int do_write_output(struct perf_record *rec, void *buf, size_t size)
{
	struct perf_data_file *file = &rec->file;

	while (size) {
		ssize_t ret = write(file->fd, buf, size);

		if (ret < 0) {
			pr_err("failed to write perf data, error: %m\n");
			return -1;
		}

		size -= ret;
		buf += ret;

		rec->bytes_written += ret;
	}

	return 0;
}

static int write_output(struct perf_record *rec, void *buf, size_t size)
{
	return do_write_output(rec, buf, size);
}

static int process_synthesized_event(struct perf_tool *tool,
				     union perf_event *event,
				     struct perf_sample *sample __maybe_unused,
				     struct machine *machine __maybe_unused)
{
	struct perf_record *rec = container_of(tool, struct perf_record, tool);
	if (write_output(rec, event, event->header.size) < 0)
		return -1;

	return 0;
}

static int perf_record__mmap_read(struct perf_record *rec,
				   struct perf_mmap *md)
{
	unsigned int head = perf_mmap__read_head(md);
	unsigned int old = md->prev;
	unsigned char *data = md->base + page_size;
	unsigned long size;
	void *buf;
	int rc = 0;

	if (old == head)
		return 0;

	rec->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;

		if (write_output(rec, buf, size) < 0) {
			rc = -1;
			goto out;
		}
	}

	buf = &data[old & md->mask];
	size = head - old;
	old += size;

	if (wr