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

// SPDX-License-Identifier: GPL-2.0
#include <linux/list.h>
#include <linux/compiler.h>
#include <sys/types.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdio.h>
#include <stdbool.h>
#include <stdarg.h>
#include <dirent.h>
#include <api/fs/fs.h>
#include <locale.h>
#include <regex.h>
#include "util.h"
#include "pmu.h"
#include "parse-events.h"
#include "cpumap.h"
#include "header.h"
#include "pmu-events/pmu-events.h"
#include "cache.h"
#include "string2.h"

struct perf_pmu_format {
	char *name;
	int value;
	DECLARE_BITMAP(bits, PERF_PMU_FORMAT_BITS);
	struct list_head list;
};

int perf_pmu_parse(struct list_head *list, char *name);
extern FILE *perf_pmu_in;

static LIST_HEAD(pmus);

/*
 * Parse & process all the sysfs attributes located under
 * the directory specified in 'dir' parameter.
 */
int perf_pmu__format_parse(char *dir, struct list_head *head)
{
	struct dirent *evt_ent;
	DIR *format_dir;
	int ret = 0;

	format_dir = opendir(dir);
	if (!format_dir)
		return -EINVAL;

	while (!ret && (evt_ent = readdir(format_dir))) {
		char path[PATH_MAX];
		char *name = evt_ent->d_name;
		FILE *file;

		if (!strcmp(name, ".") || !strcmp(name, ".."))
			continue;

		snprintf(path, PATH_MAX, "%s/%s", dir, name);

		ret = -EINVAL;
		file = fopen(path, "r");
		if (!file)
			break;

		perf_pmu_in = file;
		ret = perf_pmu_parse(head, name);
		fclose(file);
	}

	closedir(format_dir);
	return ret;
}

/*
 * Reading/parsing the default pmu format definition, which should be
 * located at:
 * /sys/bus/event_source/devices/<dev>/format as sysfs group attributes.
 */
static int pmu_format(const char *name, struct list_head *format)
{
	struct stat st;
	char path[PATH_MAX];
	const char *sysfs = sysfs__mountpoint();

	if (!sysfs)
		return -1;

	snprintf(path, PATH_MAX,
		 "%s" EVENT_SOURCE_DEVICE_PATH "%s/format", sysfs, name);

	if (stat(path, &st) < 0)
		return 0;	/* no error if format does not exist */

	if (perf_pmu__format_parse(path, format))
		return -1;

	return 0;
}

static int convert_scale(const char *scale, char **end, double *sval)
{
	char *lc;
	int ret = 0;

	/*
	 * save current locale
	 */
	lc = setlocale(LC_NUMERIC, NULL);

	/*
	 * The lc string may be allocated in static storage,
	 * so get a dynamic copy to make it survive setlocale
	 * call below.
	 */
	lc = strdup(lc);
	if (!lc) {
		ret = -ENOMEM;
		goto out;
	}

	/*
	 * force to C locale to ensure kernel
	 * scale string is converted correctly.
	 * kernel uses default C locale.
	 */
	setlocale(LC_NUMERIC, "C");

	*sval = strtod(scale, end);

out:
	/* restore locale */
	setlocale(LC_NUMERIC, lc);
	free(lc);
	return ret;
}

static int perf_pmu__parse_scale(struct perf_pmu_alias *alias, char *dir, char *name)
{
	struct stat st;
	ssize_t sret;
	char scale[128];
	int fd, ret = -1;
	char path[PATH_MAX];

	scnprintf(path, PATH_MAX, "%s/%s.scale", dir, name);

	fd = open(path, O_RDONLY);
	if (fd == -1)
		return -1;

	if (fstat(fd, &st) < 0)
		goto error;

	sret = read(fd, scale, sizeof(scale)-1);
	if (sret < 0)
		goto error;

	if (scale[sret - 1] == '\n')
		scale[sret - 1] = '\0';
	else
		scale[sret] = '\0';

	ret = convert_scale(scale, NULL, &alias->scale);
error:
	close(fd);
	return ret;
}

static int perf_pmu__parse_unit(struct perf_pmu_alias *alias, char *dir, char *name)
{
	char path[PATH_MAX];
	ssize_t sret;
	int fd;

	scnprintf(path, PATH_MAX, "%s/%s.unit", dir, name);

	fd = open(path, O_RDONLY);
	if (fd == -1)
		return -1;

	sret = read(fd, alias->unit, UNIT_MAX_LEN);
	if (sret < 0)
		goto error;

	close(fd);

	if (alias->unit[sret - 1] == '\n')
		alias->unit[sret - 1] = '\0';
	else
		alias->unit[sret] = '\0';

	return 0;
error:
	close(fd);
	alias->unit[0] = '\0';
	return -1;
}

static int
perf_pmu__parse_per_pkg(struct perf_pmu_alias *alias, char *dir, char *name)
{
	char path[PATH_MAX];
	int fd;

	scnprintf(path, PATH_MAX, "%s/%s.per-pkg", dir, name);

	fd = open(path, O_RDONLY);
	if (fd == -1)
		return -1;

	close(fd);

	alias->per_pkg = true;
	return 0;
}

static int perf_pmu__parse_snapshot(struct perf_pmu_alias *alias,
				    char *dir, char *name)
{
	char path[PATH_MAX];
	int fd;

	scnprintf(path, PATH_MAX, "%s/%s.snapshot", dir, name);

	fd = open(path, O_RDONLY);
	if (fd == -1)
		return -1;

	alias->snapshot = true;
	close(fd);
	return 0;
}

static void perf_pmu_assign_str(char *name, const char *field, char **old_str,
				char **new_str)
{
	if (!*old_str)
		goto set_new;

	if (*new_str) {	/* Have new string, check with old */
		if (strcasecmp(*old_str, *new_str))
			pr_debug("alias %s differs in field '%s'\n",
				 name, field);
		zfree(old_str);
	} else		/* Nothing new --> keep old string */
		return;
set_new:
	*old_str = *new_str;
	*new_str = NULL;
}

static void perf_pmu_update_alias(struct perf_pmu_alias *old,
				  struct perf_pmu_alias *newalias)
{
	perf_pmu_assign_str(old->name, "desc", &old->desc, &newalias->desc);
	perf_pmu_assign_str(old->name, "long_desc", &old->long_desc,
			    &newalias->long_desc);
	perf_pmu_assign_str(old->name, "topic", &old->topic, &newalias->topic);
	perf_pmu_assign_str(old->name, "metric_expr", &old->metric_expr,
			    &newalias->metric_expr);
	perf_pmu_assign_str(old->name, "metric_name", &old->metric_name,
			    &newalias->metric_name);
	perf_pmu_assign_str(old->name, "value", &old->str, &newalias->str);
	old->scale = newalias->scale;
	old->per_pkg = newalias->per_pkg;
	old->snapshot = newalias->snapshot;
	memcpy(old->unit, newalias->unit, sizeof(old->unit));
}

/* Delete an alias entry. */
static void perf_pmu_free_alias(struct perf_pmu_alias *newalias)
{
	zfree(&newalias->name);
	zfree(&newalias->desc);
	zfree(&newalias->long_desc);
	zfree(&newalias->topic);
	zfree(&newalias->str);
	zfree(&newalias->metric_expr);
	zfree(&newalias->metric_name);
	parse_events_terms__purge(&newalias->terms);
	free(newalias);
}

/* Merge an alias, search in alias list. If this name is already
 * present merge both of them to combine all information.
 */
static bool perf_pmu_merge_alias(struct perf_pmu_alias *newalias,
				 struct list_head *alist)
{
	struct perf_pmu_alias *a;

	list_for_each_entry(a, alist, list) {
		if (!strcasecmp(newalias->name, a->name)) {
			perf_pmu_update_alias(a, newalias);
			perf_pmu_free_alias(newalias);
			return true;
		}
	}
	return false;
}

static int __perf_pmu__new_alias(struct list_head *list, char *dir, char *name,
				 char *desc, char *val,
				 char *long_desc, char *topic,
				 char *unit, char *perpkg,
				 char *metric_expr,
				 char *metric_name)
{
	struct parse_events_term *term;
	struct perf_pmu_alias *alias;
	int ret;
	int num;
	char newval[256];

	alias = malloc(sizeof(*alias));
	if (!alias)
		return -ENOMEM;

	INIT_LIST_HEAD(&alias->terms);
	alias->scale = 1.0;
	alias->unit[0] = '\0';
	alias->per_pkg = false;
	alias->snapshot = false;

	ret = parse_events_terms(&alias->terms, val);
	if (ret) {
		pr_err("Cannot parse alias %s: %d\n", val, ret);
		free(alias);
		return ret;
	}

	/* Scan event and remove leading zeroes, spaces, newlines, some
	 * platforms have terms specified as
	 * event=0x0091 (read from files ../<PMU>/events/<FILE>
	 * and terms specified as event=0x91 (read from JSON files).
	 *
	 * Rebuild string to make alias->str member comparable.
	 */
	memset(newval, 0, sizeof(newval));
	ret = 0;
	list_for_each_entry(term, &alias->terms, list) {
		if (ret)
			ret += scnprintf(newval + ret, sizeof(newval) - ret,
					 ",");
		if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM)
			ret += scnprintf(newval + ret, sizeof(newval) - ret,
					 "%s=