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.
 */
#define _FILE_OFFSET_BITS 64

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

enum write_mode_t {
	WRITE_FORCE,
	WRITE_APPEND
};

struct perf_record {
	struct perf_tool	tool;
	struct perf_record_opts	opts;
	u64			bytes_written;
	const char		*output_name;
	struct perf_evlist	*evlist;
	struct perf_session	*session;
	const char		*progname;
	int			output;
	unsigned int		page_size;
	int			realtime_prio;
	enum write_mode_t	write_mode;
	bool			no_buildid;
	bool			no_buildid_cache;
	bool			force;
	bool			file_new;
	bool			append_file;
	long			samples;
	off_t			post_processing_offset;
};

static void advance_output(struct perf_record *rec, size_t size)
{
	rec->bytes_written += size;
}

static void write_output(struct perf_record *rec, void *buf, size_t size)
{
	while (size) {
		int ret = write(rec->output, buf, size);

		if (ret < 0)
			die("failed to write");

		size -= ret;
		buf += ret;

		rec->bytes_written += ret;
	}
}

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

static void 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 + rec->page_size;
	unsigned long size;
	void *buf;

	if (old == head)
		return;

	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;

		write_output(rec, buf, size);
	}

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

	write_output(rec, buf, size);

	md->prev = old;
	perf_mmap__write_tail(md, old);
}

static volatile int done = 0;
static volatile int signr = -1;
static volatile int child_finished = 0;

static void sig_handler(int sig)
{
	if (sig == SIGCHLD)
		child_finished = 1;

	done = 1;
	signr = sig;
}

static void perf_record__sig_exit(int exit_status __used, void *arg)
{
	struct perf_record *rec = arg;
	int status;

	if (rec->evlist->workload.pid > 0) {
		if (!child_finished)
			kill(rec->evlist->workload.pid, SIGTERM);

		wait(&status);
		if (WIFSIGNALED(status))
			psignal(WTERMSIG(status), rec->progname);
	}

	if (signr == -1 || signr == SIGUSR1)
		return;

	signal(signr, SIG_DFL);
	kill(getpid(), signr);
}

static bool perf_evlist__equal(struct perf_evlist *evlist,
			       struct perf_evlist *other)
{
	struct perf_evsel *pos, *pair;

	if (evlist->nr_entries