perf_examples/perf_util.h

/*
 * perf_util.h - helper functions for perf_events
 *
 * Copyright (c) 2009 Google, Inc
 * Contributed by Stephane Eranian <eranian@gmail.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
 * of the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
 * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
 * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
 * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
 * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
#ifndef __PERF_UTIL_H__
#define __PERF_UTIL_H__

#include <sys/types.h>
#include <inttypes.h>
#include <err.h>
#include <perfmon/pfmlib_perf_event.h>

typedef struct {
	struct perf_event_attr hw;
	uint64_t values[3];
	uint64_t prev_values[3];
	char *name;
	uint64_t id; /* event id kernel */
	void *buf;
	size_t pgmsk;
	int group_leader;
	int fd;
	int max_fds;
	int idx; /* opaque libpfm event identifier */
	int cpu; /* cpu to program */
	char *fstr; /* fstr from library, must be freed */
} perf_event_desc_t;

/* handy shortcut */
#define PERF_FORMAT_SCALE (PERF_FORMAT_TOTAL_TIME_ENABLED|PERF_FORMAT_TOTAL_TIME_RUNNING)

extern int perf_setup_argv_events(const char **argv, perf_event_desc_t **fd, int *num_fds);
extern int perf_setup_list_events(const char *events, perf_event_desc_t **fd, int *num_fds);
extern int perf_read_buffer(perf_event_desc_t *hw, void *buf, size_t sz);
extern void perf_free_fds(perf_event_desc_t *fds, int num_fds);
extern void perf_skip_buffer(perf_event_desc_t *hw, size_t sz);

static inline int
perf_read_buffer_32(perf_event_desc_t *hw, void *buf)
{
	return perf_read_buffer(hw, buf, sizeof(uint32_t));
}

static inline int
perf_read_buffer_64(perf_event_desc_t *hw, void *buf)
{
	return perf_read_buffer(hw, buf, sizeof(uint64_t));
}

/*
 * values[0] = raw count
 * values[1] = TIME_ENABLED
 * values[2] = TIME_RUNNING
 */
static inline uint64_t
perf_scale(uint64_t *values)
{
	uint64_t res = 0;

	if (!values[2] && !values[1] && values[0])
		warnx("WARNING: time_running = 0 = time_enabled, raw count not zero\n");

	if (values[2] > values[1])
		warnx("WARNING: time_running > time_enabled\n");

	if (values[2])
		res = (uint64_t)((double)values[0] * values[1]/values[2]);
	return res;
}

static inline uint64_t
perf_scale_delta(uint64_t *values, uint64_t *prev_values)
{
	double pval[3], val[3];
	uint64_t res = 0;

	if (!values[2] && !values[1] && values[0])
		warnx("WARNING: time_running = 0 = time_enabled, raw count not zero\n");

	if (values[2] > values[1])
		warnx("WARNING: time_running > time_enabled\n");

	if (values[2] - prev_values[2]) {
		/* covnert everything to double to avoid overflows! */
		pval[0] = prev_values[0];
		pval[1] = prev_values[1];
		pval[2] = prev_values[2];
		val[0] = values[0];
		val[1] = values[1];
		val[2] = values[2];
		res = (uint64_t)(((val[0] - pval[0]) * (val[1] - pval[1])/ (val[2] - pval[2])));
	}
	return res;
}


/*
 * TIME_RUNNING/TIME_ENABLED
 */
static inline double
perf_scale_ratio(uint64_t *values)
{
	if (!values[1])
		return 0.0;

	return values[2]*1.0/values[1];
}

static inline int
perf_fd2event(perf_event_desc_t *fds, int num_events, int fd)
{
	int i;

	for(i=0; i < num_events; i++)
		if (fds[i].fd == fd)
			return i;
	return -1;
}

/*
 * id = PERF_FORMAT_ID
 */
static inline int
perf_id2event(perf_event_desc_t *fds, int num_events, uint64_t id)
{
	int j;
	for(j=0; j < num_events; j++)
		if (fds[j].id == id)
			return j;
	return -1;
}

static inline int
perf_is_group_leader(perf_event_desc_t *fds, int idx)
{
	return fds[idx].group_leader == idx;
}

extern int perf_get_group_nevents(perf_event_desc_t *fds, int num, int leader);
extern int perf_display_sample(perf_event_desc_t *fds, int num_fds, int idx, struct perf_event_header *ehdr, FILE *fp);
extern uint64_t display_lost(perf_event_desc_t *hw, perf_event_desc_t *fds, int num_fds, FILE *fp);
extern void display_exit(perf_event_desc_t *hw, FILE *fp);
extern void display_freq(int mode, perf_event_desc_t *hw, FILE *fp);
#endif