xref: /openbmc/linux/tools/perf/util/pmu.c (revision 32067712)
1 #include <linux/list.h>
2 #include <linux/compiler.h>
3 #include <sys/types.h>
4 #include <unistd.h>
5 #include <stdio.h>
6 #include <stdbool.h>
7 #include <stdarg.h>
8 #include <dirent.h>
9 #include <api/fs/fs.h>
10 #include <locale.h>
11 #include "util.h"
12 #include "pmu.h"
13 #include "parse-events.h"
14 #include "cpumap.h"
15 
16 struct perf_pmu_format {
17 	char *name;
18 	int value;
19 	DECLARE_BITMAP(bits, PERF_PMU_FORMAT_BITS);
20 	struct list_head list;
21 };
22 
23 #define EVENT_SOURCE_DEVICE_PATH "/bus/event_source/devices/"
24 
25 int perf_pmu_parse(struct list_head *list, char *name);
26 extern FILE *perf_pmu_in;
27 
28 static LIST_HEAD(pmus);
29 
30 /*
31  * Parse & process all the sysfs attributes located under
32  * the directory specified in 'dir' parameter.
33  */
34 int perf_pmu__format_parse(char *dir, struct list_head *head)
35 {
36 	struct dirent *evt_ent;
37 	DIR *format_dir;
38 	int ret = 0;
39 
40 	format_dir = opendir(dir);
41 	if (!format_dir)
42 		return -EINVAL;
43 
44 	while (!ret && (evt_ent = readdir(format_dir))) {
45 		char path[PATH_MAX];
46 		char *name = evt_ent->d_name;
47 		FILE *file;
48 
49 		if (!strcmp(name, ".") || !strcmp(name, ".."))
50 			continue;
51 
52 		snprintf(path, PATH_MAX, "%s/%s", dir, name);
53 
54 		ret = -EINVAL;
55 		file = fopen(path, "r");
56 		if (!file)
57 			break;
58 
59 		perf_pmu_in = file;
60 		ret = perf_pmu_parse(head, name);
61 		fclose(file);
62 	}
63 
64 	closedir(format_dir);
65 	return ret;
66 }
67 
68 /*
69  * Reading/parsing the default pmu format definition, which should be
70  * located at:
71  * /sys/bus/event_source/devices/<dev>/format as sysfs group attributes.
72  */
73 static int pmu_format(const char *name, struct list_head *format)
74 {
75 	struct stat st;
76 	char path[PATH_MAX];
77 	const char *sysfs = sysfs__mountpoint();
78 
79 	if (!sysfs)
80 		return -1;
81 
82 	snprintf(path, PATH_MAX,
83 		 "%s" EVENT_SOURCE_DEVICE_PATH "%s/format", sysfs, name);
84 
85 	if (stat(path, &st) < 0)
86 		return 0;	/* no error if format does not exist */
87 
88 	if (perf_pmu__format_parse(path, format))
89 		return -1;
90 
91 	return 0;
92 }
93 
94 static int perf_pmu__parse_scale(struct perf_pmu_alias *alias, char *dir, char *name)
95 {
96 	struct stat st;
97 	ssize_t sret;
98 	char scale[128];
99 	int fd, ret = -1;
100 	char path[PATH_MAX];
101 	const char *lc;
102 
103 	snprintf(path, PATH_MAX, "%s/%s.scale", dir, name);
104 
105 	fd = open(path, O_RDONLY);
106 	if (fd == -1)
107 		return -1;
108 
109 	if (fstat(fd, &st) < 0)
110 		goto error;
111 
112 	sret = read(fd, scale, sizeof(scale)-1);
113 	if (sret < 0)
114 		goto error;
115 
116 	if (scale[sret - 1] == '\n')
117 		scale[sret - 1] = '\0';
118 	else
119 		scale[sret] = '\0';
120 
121 	/*
122 	 * save current locale
123 	 */
124 	lc = setlocale(LC_NUMERIC, NULL);
125 
126 	/*
127 	 * force to C locale to ensure kernel
128 	 * scale string is converted correctly.
129 	 * kernel uses default C locale.
130 	 */
131 	setlocale(LC_NUMERIC, "C");
132 
133 	alias->scale = strtod(scale, NULL);
134 
135 	/* restore locale */
136 	setlocale(LC_NUMERIC, lc);
137 
138 	ret = 0;
139 error:
140 	close(fd);
141 	return ret;
142 }
143 
144 static int perf_pmu__parse_unit(struct perf_pmu_alias *alias, char *dir, char *name)
145 {
146 	char path[PATH_MAX];
147 	ssize_t sret;
148 	int fd;
149 
150 	snprintf(path, PATH_MAX, "%s/%s.unit", dir, name);
151 
152 	fd = open(path, O_RDONLY);
153 	if (fd == -1)
154 		return -1;
155 
156 		sret = read(fd, alias->unit, UNIT_MAX_LEN);
157 	if (sret < 0)
158 		goto error;
159 
160 	close(fd);
161 
162 	if (alias->unit[sret - 1] == '\n')
163 		alias->unit[sret - 1] = '\0';
164 	else
165 		alias->unit[sret] = '\0';
166 
167 	return 0;
168 error:
169 	close(fd);
170 	alias->unit[0] = '\0';
171 	return -1;
172 }
173 
174 static int
175 perf_pmu__parse_per_pkg(struct perf_pmu_alias *alias, char *dir, char *name)
176 {
177 	char path[PATH_MAX];
178 	int fd;
179 
180 	snprintf(path, PATH_MAX, "%s/%s.per-pkg", dir, name);
181 
182 	fd = open(path, O_RDONLY);
183 	if (fd == -1)
184 		return -1;
185 
186 	close(fd);
187 
188 	alias->per_pkg = true;
189 	return 0;
190 }
191 
192 static int perf_pmu__parse_snapshot(struct perf_pmu_alias *alias,
193 				    char *dir, char *name)
194 {
195 	char path[PATH_MAX];
196 	int fd;
197 
198 	snprintf(path, PATH_MAX, "%s/%s.snapshot", dir, name);
199 
200 	fd = open(path, O_RDONLY);
201 	if (fd == -1)
202 		return -1;
203 
204 	alias->snapshot = true;
205 	close(fd);
206 	return 0;
207 }
208 
209 static int __perf_pmu__new_alias(struct list_head *list, char *dir, char *name,
210 				 char *desc __maybe_unused, char *val)
211 {
212 	struct perf_pmu_alias *alias;
213 	int ret;
214 
215 	alias = malloc(sizeof(*alias));
216 	if (!alias)
217 		return -ENOMEM;
218 
219 	INIT_LIST_HEAD(&alias->terms);
220 	alias->scale = 1.0;
221 	alias->unit[0] = '\0';
222 	alias->per_pkg = false;
223 
224 	ret = parse_events_terms(&alias->terms, val);
225 	if (ret) {
226 		pr_err("Cannot parse alias %s: %d\n", val, ret);
227 		free(alias);
228 		return ret;
229 	}
230 
231 	alias->name = strdup(name);
232 	if (dir) {
233 		/*
234 		 * load unit name and scale if available
235 		 */
236 		perf_pmu__parse_unit(alias, dir, name);
237 		perf_pmu__parse_scale(alias, dir, name);
238 		perf_pmu__parse_per_pkg(alias, dir, name);
239 		perf_pmu__parse_snapshot(alias, dir, name);
240 	}
241 
242 	list_add_tail(&alias->list, list);
243 
244 	return 0;
245 }
246 
247 static int perf_pmu__new_alias(struct list_head *list, char *dir, char *name, FILE *file)
248 {
249 	char buf[256];
250 	int ret;
251 
252 	ret = fread(buf, 1, sizeof(buf), file);
253 	if (ret == 0)
254 		return -EINVAL;
255 
256 	buf[ret] = 0;
257 
258 	return __perf_pmu__new_alias(list, dir, name, NULL, buf);
259 }
260 
261 static inline bool pmu_alias_info_file(char *name)
262 {
263 	size_t len;
264 
265 	len = strlen(name);
266 	if (len > 5 && !strcmp(name + len - 5, ".unit"))
267 		return true;
268 	if (len > 6 && !strcmp(name + len - 6, ".scale"))
269 		return true;
270 	if (len > 8 && !strcmp(name + len - 8, ".per-pkg"))
271 		return true;
272 	if (len > 9 && !strcmp(name + len - 9, ".snapshot"))
273 		return true;
274 
275 	return false;
276 }
277 
278 /*
279  * Process all the sysfs attributes located under the directory
280  * specified in 'dir' parameter.
281  */
282 static int pmu_aliases_parse(char *dir, struct list_head *head)
283 {
284 	struct dirent *evt_ent;
285 	DIR *event_dir;
286 	int ret = 0;
287 
288 	event_dir = opendir(dir);
289 	if (!event_dir)
290 		return -EINVAL;
291 
292 	while (!ret && (evt_ent = readdir(event_dir))) {
293 		char path[PATH_MAX];
294 		char *name = evt_ent->d_name;
295 		FILE *file;
296 
297 		if (!strcmp(name, ".") || !strcmp(name, ".."))
298 			continue;
299 
300 		/*
301 		 * skip info files parsed in perf_pmu__new_alias()
302 		 */
303 		if (pmu_alias_info_file(name))
304 			continue;
305 
306 		snprintf(path, PATH_MAX, "%s/%s", dir, name);
307 
308 		ret = -EINVAL;
309 		file = fopen(path, "r");
310 		if (!file)
311 			break;
312 
313 		ret = perf_pmu__new_alias(head, dir, name, file);
314 		fclose(file);
315 	}
316 
317 	closedir(event_dir);
318 	return ret;
319 }
320 
321 /*
322  * Reading the pmu event aliases definition, which should be located at:
323  * /sys/bus/event_source/devices/<dev>/events as sysfs group attributes.
324  */
325 static int pmu_aliases(const char *name, struct list_head *head)
326 {
327 	struct stat st;
328 	char path[PATH_MAX];
329 	const char *sysfs = sysfs__mountpoint();
330 
331 	if (!sysfs)
332 		return -1;
333 
334 	snprintf(path, PATH_MAX,
335 		 "%s/bus/event_source/devices/%s/events", sysfs, name);
336 
337 	if (stat(path, &st) < 0)
338 		return 0;	 /* no error if 'events' does not exist */
339 
340 	if (pmu_aliases_parse(path, head))
341 		return -1;
342 
343 	return 0;
344 }
345 
346 static int pmu_alias_terms(struct perf_pmu_alias *alias,
347 			   struct list_head *terms)
348 {
349 	struct parse_events_term *term, *cloned;
350 	LIST_HEAD(list);
351 	int ret;
352 
353 	list_for_each_entry(term, &alias->terms, list) {
354 		ret = parse_events_term__clone(&cloned, term);
355 		if (ret) {
356 			parse_events__free_terms(&list);
357 			return ret;
358 		}
359 		list_add_tail(&cloned->list, &list);
360 	}
361 	list_splice(&list, terms);
362 	return 0;
363 }
364 
365 /*
366  * Reading/parsing the default pmu type value, which should be
367  * located at:
368  * /sys/bus/event_source/devices/<dev>/type as sysfs attribute.
369  */
370 static int pmu_type(const char *name, __u32 *type)
371 {
372 	struct stat st;
373 	char path[PATH_MAX];
374 	FILE *file;
375 	int ret = 0;
376 	const char *sysfs = sysfs__mountpoint();
377 
378 	if (!sysfs)
379 		return -1;
380 
381 	snprintf(path, PATH_MAX,
382 		 "%s" EVENT_SOURCE_DEVICE_PATH "%s/type", sysfs, name);
383 
384 	if (stat(path, &st) < 0)
385 		return -1;
386 
387 	file = fopen(path, "r");
388 	if (!file)
389 		return -EINVAL;
390 
391 	if (1 != fscanf(file, "%u", type))
392 		ret = -1;
393 
394 	fclose(file);
395 	return ret;
396 }
397 
398 /* Add all pmus in sysfs to pmu list: */
399 static void pmu_read_sysfs(void)
400 {
401 	char path[PATH_MAX];
402 	DIR *dir;
403 	struct dirent *dent;
404 	const char *sysfs = sysfs__mountpoint();
405 
406 	if (!sysfs)
407 		return;
408 
409 	snprintf(path, PATH_MAX,
410 		 "%s" EVENT_SOURCE_DEVICE_PATH, sysfs);
411 
412 	dir = opendir(path);
413 	if (!dir)
414 		return;
415 
416 	while ((dent = readdir(dir))) {
417 		if (!strcmp(dent->d_name, ".") || !strcmp(dent->d_name, ".."))
418 			continue;
419 		/* add to static LIST_HEAD(pmus): */
420 		perf_pmu__find(dent->d_name);
421 	}
422 
423 	closedir(dir);
424 }
425 
426 static struct cpu_map *pmu_cpumask(const char *name)
427 {
428 	struct stat st;
429 	char path[PATH_MAX];
430 	FILE *file;
431 	struct cpu_map *cpus;
432 	const char *sysfs = sysfs__mountpoint();
433 
434 	if (!sysfs)
435 		return NULL;
436 
437 	snprintf(path, PATH_MAX,
438 		 "%s/bus/event_source/devices/%s/cpumask", sysfs, name);
439 
440 	if (stat(path, &st) < 0)
441 		return NULL;
442 
443 	file = fopen(path, "r");
444 	if (!file)
445 		return NULL;
446 
447 	cpus = cpu_map__read(file);
448 	fclose(file);
449 	return cpus;
450 }
451 
452 struct perf_event_attr * __weak
453 perf_pmu__get_default_config(struct perf_pmu *pmu __maybe_unused)
454 {
455 	return NULL;
456 }
457 
458 static struct perf_pmu *pmu_lookup(const char *name)
459 {
460 	struct perf_pmu *pmu;
461 	LIST_HEAD(format);
462 	LIST_HEAD(aliases);
463 	__u32 type;
464 
465 	/* No support for intel_bts or intel_pt so disallow them */
466 	if (!strcmp(name, "intel_bts") || !strcmp(name, "intel_pt"))
467 		return NULL;
468 
469 	/*
470 	 * The pmu data we store & need consists of the pmu
471 	 * type value and format definitions. Load both right
472 	 * now.
473 	 */
474 	if (pmu_format(name, &format))
475 		return NULL;
476 
477 	if (pmu_aliases(name, &aliases))
478 		return NULL;
479 
480 	if (pmu_type(name, &type))
481 		return NULL;
482 
483 	pmu = zalloc(sizeof(*pmu));
484 	if (!pmu)
485 		return NULL;
486 
487 	pmu->cpus = pmu_cpumask(name);
488 
489 	INIT_LIST_HEAD(&pmu->format);
490 	INIT_LIST_HEAD(&pmu->aliases);
491 	list_splice(&format, &pmu->format);
492 	list_splice(&aliases, &pmu->aliases);
493 	pmu->name = strdup(name);
494 	pmu->type = type;
495 	list_add_tail(&pmu->list, &pmus);
496 
497 	pmu->default_config = perf_pmu__get_default_config(pmu);
498 
499 	return pmu;
500 }
501 
502 static struct perf_pmu *pmu_find(const char *name)
503 {
504 	struct perf_pmu *pmu;
505 
506 	list_for_each_entry(pmu, &pmus, list)
507 		if (!strcmp(pmu->name, name))
508 			return pmu;
509 
510 	return NULL;
511 }
512 
513 struct perf_pmu *perf_pmu__scan(struct perf_pmu *pmu)
514 {
515 	/*
516 	 * pmu iterator: If pmu is NULL, we start at the begin,
517 	 * otherwise return the next pmu. Returns NULL on end.
518 	 */
519 	if (!pmu) {
520 		pmu_read_sysfs();
521 		pmu = list_prepare_entry(pmu, &pmus, list);
522 	}
523 	list_for_each_entry_continue(pmu, &pmus, list)
524 		return pmu;
525 	return NULL;
526 }
527 
528 struct perf_pmu *perf_pmu__find(const char *name)
529 {
530 	struct perf_pmu *pmu;
531 
532 	/*
533 	 * Once PMU is loaded it stays in the list,
534 	 * so we keep us from multiple reading/parsing
535 	 * the pmu format definitions.
536 	 */
537 	pmu = pmu_find(name);
538 	if (pmu)
539 		return pmu;
540 
541 	return pmu_lookup(name);
542 }
543 
544 static struct perf_pmu_format *
545 pmu_find_format(struct list_head *formats, char *name)
546 {
547 	struct perf_pmu_format *format;
548 
549 	list_for_each_entry(format, formats, list)
550 		if (!strcmp(format->name, name))
551 			return format;
552 
553 	return NULL;
554 }
555 
556 /*
557  * Sets value based on the format definition (format parameter)
558  * and unformated value (value parameter).
559  */
560 static void pmu_format_value(unsigned long *format, __u64 value, __u64 *v,
561 			     bool zero)
562 {
563 	unsigned long fbit, vbit;
564 
565 	for (fbit = 0, vbit = 0; fbit < PERF_PMU_FORMAT_BITS; fbit++) {
566 
567 		if (!test_bit(fbit, format))
568 			continue;
569 
570 		if (value & (1llu << vbit++))
571 			*v |= (1llu << fbit);
572 		else if (zero)
573 			*v &= ~(1llu << fbit);
574 	}
575 }
576 
577 /*
578  * Term is a string term, and might be a param-term. Try to look up it's value
579  * in the remaining terms.
580  * - We have a term like "base-or-format-term=param-term",
581  * - We need to find the value supplied for "param-term" (with param-term named
582  *   in a config string) later on in the term list.
583  */
584 static int pmu_resolve_param_term(struct parse_events_term *term,
585 				  struct list_head *head_terms,
586 				  __u64 *value)
587 {
588 	struct parse_events_term *t;
589 
590 	list_for_each_entry(t, head_terms, list) {
591 		if (t->type_val == PARSE_EVENTS__TERM_TYPE_NUM) {
592 			if (!strcmp(t->config, term->config)) {
593 				t->used = true;
594 				*value = t->val.num;
595 				return 0;
596 			}
597 		}
598 	}
599 
600 	if (verbose)
601 		printf("Required parameter '%s' not specified\n", term->config);
602 
603 	return -1;
604 }
605 
606 static char *formats_error_string(struct list_head *formats)
607 {
608 	struct perf_pmu_format *format;
609 	char *err, *str;
610 	static const char *static_terms = "config,config1,config2,name,period,branch_type,time\n";
611 	unsigned i = 0;
612 
613 	if (!asprintf(&str, "valid terms:"))
614 		return NULL;
615 
616 	/* sysfs exported terms */
617 	list_for_each_entry(format, formats, list) {
618 		char c = i++ ? ',' : ' ';
619 
620 		err = str;
621 		if (!asprintf(&str, "%s%c%s", err, c, format->name))
622 			goto fail;
623 		free(err);
624 	}
625 
626 	/* static terms */
627 	err = str;
628 	if (!asprintf(&str, "%s,%s", err, static_terms))
629 		goto fail;
630 
631 	free(err);
632 	return str;
633 fail:
634 	free(err);
635 	return NULL;
636 }
637 
638 /*
639  * Setup one of config[12] attr members based on the
640  * user input data - term parameter.
641  */
642 static int pmu_config_term(struct list_head *formats,
643 			   struct perf_event_attr *attr,
644 			   struct parse_events_term *term,
645 			   struct list_head *head_terms,
646 			   bool zero, struct parse_events_error *err)
647 {
648 	struct perf_pmu_format *format;
649 	__u64 *vp;
650 	__u64 val;
651 
652 	/*
653 	 * If this is a parameter we've already used for parameterized-eval,
654 	 * skip it in normal eval.
655 	 */
656 	if (term->used)
657 		return 0;
658 
659 	/*
660 	 * Hardcoded terms should be already in, so nothing
661 	 * to be done for them.
662 	 */
663 	if (parse_events__is_hardcoded_term(term))
664 		return 0;
665 
666 	format = pmu_find_format(formats, term->config);
667 	if (!format) {
668 		if (verbose)
669 			printf("Invalid event/parameter '%s'\n", term->config);
670 		if (err) {
671 			err->idx  = term->err_term;
672 			err->str  = strdup("unknown term");
673 			err->help = formats_error_string(formats);
674 		}
675 		return -EINVAL;
676 	}
677 
678 	switch (format->value) {
679 	case PERF_PMU_FORMAT_VALUE_CONFIG:
680 		vp = &attr->config;
681 		break;
682 	case PERF_PMU_FORMAT_VALUE_CONFIG1:
683 		vp = &attr->config1;
684 		break;
685 	case PERF_PMU_FORMAT_VALUE_CONFIG2:
686 		vp = &attr->config2;
687 		break;
688 	default:
689 		return -EINVAL;
690 	}
691 
692 	/*
693 	 * Either directly use a numeric term, or try to translate string terms
694 	 * using event parameters.
695 	 */
696 	if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM)
697 		val = term->val.num;
698 	else if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR) {
699 		if (strcmp(term->val.str, "?")) {
700 			if (verbose) {
701 				pr_info("Invalid sysfs entry %s=%s\n",
702 						term->config, term->val.str);
703 			}
704 			if (err) {
705 				err->idx = term->err_val;
706 				err->str = strdup("expected numeric value");
707 			}
708 			return -EINVAL;
709 		}
710 
711 		if (pmu_resolve_param_term(term, head_terms, &val))
712 			return -EINVAL;
713 	} else
714 		return -EINVAL;
715 
716 	pmu_format_value(format->bits, val, vp, zero);
717 	return 0;
718 }
719 
720 int perf_pmu__config_terms(struct list_head *formats,
721 			   struct perf_event_attr *attr,
722 			   struct list_head *head_terms,
723 			   bool zero, struct parse_events_error *err)
724 {
725 	struct parse_events_term *term;
726 
727 	list_for_each_entry(term, head_terms, list) {
728 		if (pmu_config_term(formats, attr, term, head_terms,
729 				    zero, err))
730 			return -EINVAL;
731 	}
732 
733 	return 0;
734 }
735 
736 /*
737  * Configures event's 'attr' parameter based on the:
738  * 1) users input - specified in terms parameter
739  * 2) pmu format definitions - specified by pmu parameter
740  */
741 int perf_pmu__config(struct perf_pmu *pmu, struct perf_event_attr *attr,
742 		     struct list_head *head_terms,
743 		     struct parse_events_error *err)
744 {
745 	bool zero = !!pmu->default_config;
746 
747 	attr->type = pmu->type;
748 	return perf_pmu__config_terms(&pmu->format, attr, head_terms,
749 				      zero, err);
750 }
751 
752 static struct perf_pmu_alias *pmu_find_alias(struct perf_pmu *pmu,
753 					     struct parse_events_term *term)
754 {
755 	struct perf_pmu_alias *alias;
756 	char *name;
757 
758 	if (parse_events__is_hardcoded_term(term))
759 		return NULL;
760 
761 	if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM) {
762 		if (term->val.num != 1)
763 			return NULL;
764 		if (pmu_find_format(&pmu->format, term->config))
765 			return NULL;
766 		name = term->config;
767 	} else if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR) {
768 		if (strcasecmp(term->config, "event"))
769 			return NULL;
770 		name = term->val.str;
771 	} else {
772 		return NULL;
773 	}
774 
775 	list_for_each_entry(alias, &pmu->aliases, list) {
776 		if (!strcasecmp(alias->name, name))
777 			return alias;
778 	}
779 	return NULL;
780 }
781 
782 
783 static int check_info_data(struct perf_pmu_alias *alias,
784 			   struct perf_pmu_info *info)
785 {
786 	/*
787 	 * Only one term in event definition can
788 	 * define unit, scale and snapshot, fail
789 	 * if there's more than one.
790 	 */
791 	if ((info->unit && alias->unit) ||
792 	    (info->scale && alias->scale) ||
793 	    (info->snapshot && alias->snapshot))
794 		return -EINVAL;
795 
796 	if (alias->unit)
797 		info->unit = alias->unit;
798 
799 	if (alias->scale)
800 		info->scale = alias->scale;
801 
802 	if (alias->snapshot)
803 		info->snapshot = alias->snapshot;
804 
805 	return 0;
806 }
807 
808 /*
809  * Find alias in the terms list and replace it with the terms
810  * defined for the alias
811  */
812 int perf_pmu__check_alias(struct perf_pmu *pmu, struct list_head *head_terms,
813 			  struct perf_pmu_info *info)
814 {
815 	struct parse_events_term *term, *h;
816 	struct perf_pmu_alias *alias;
817 	int ret;
818 
819 	info->per_pkg = false;
820 
821 	/*
822 	 * Mark unit and scale as not set
823 	 * (different from default values, see below)
824 	 */
825 	info->unit     = NULL;
826 	info->scale    = 0.0;
827 	info->snapshot = false;
828 
829 	list_for_each_entry_safe(term, h, head_terms, list) {
830 		alias = pmu_find_alias(pmu, term);
831 		if (!alias)
832 			continue;
833 		ret = pmu_alias_terms(alias, &term->list);
834 		if (ret)
835 			return ret;
836 
837 		ret = check_info_data(alias, info);
838 		if (ret)
839 			return ret;
840 
841 		if (alias->per_pkg)
842 			info->per_pkg = true;
843 
844 		list_del(&term->list);
845 		free(term);
846 	}
847 
848 	/*
849 	 * if no unit or scale foundin aliases, then
850 	 * set defaults as for evsel
851 	 * unit cannot left to NULL
852 	 */
853 	if (info->unit == NULL)
854 		info->unit   = "";
855 
856 	if (info->scale == 0.0)
857 		info->scale  = 1.0;
858 
859 	return 0;
860 }
861 
862 int perf_pmu__new_format(struct list_head *list, char *name,
863 			 int config, unsigned long *bits)
864 {
865 	struct perf_pmu_format *format;
866 
867 	format = zalloc(sizeof(*format));
868 	if (!format)
869 		return -ENOMEM;
870 
871 	format->name = strdup(name);
872 	format->value = config;
873 	memcpy(format->bits, bits, sizeof(format->bits));
874 
875 	list_add_tail(&format->list, list);
876 	return 0;
877 }
878 
879 void perf_pmu__set_format(unsigned long *bits, long from, long to)
880 {
881 	long b;
882 
883 	if (!to)
884 		to = from;
885 
886 	memset(bits, 0, BITS_TO_BYTES(PERF_PMU_FORMAT_BITS));
887 	for (b = from; b <= to; b++)
888 		set_bit(b, bits);
889 }
890 
891 static int sub_non_neg(int a, int b)
892 {
893 	if (b > a)
894 		return 0;
895 	return a - b;
896 }
897 
898 static char *format_alias(char *buf, int len, struct perf_pmu *pmu,
899 			  struct perf_pmu_alias *alias)
900 {
901 	struct parse_events_term *term;
902 	int used = snprintf(buf, len, "%s/%s", pmu->name, alias->name);
903 
904 	list_for_each_entry(term, &alias->terms, list) {
905 		if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR)
906 			used += snprintf(buf + used, sub_non_neg(len, used),
907 					",%s=%s", term->config,
908 					term->val.str);
909 	}
910 
911 	if (sub_non_neg(len, used) > 0) {
912 		buf[used] = '/';
913 		used++;
914 	}
915 	if (sub_non_neg(len, used) > 0) {
916 		buf[used] = '\0';
917 		used++;
918 	} else
919 		buf[len - 1] = '\0';
920 
921 	return buf;
922 }
923 
924 static char *format_alias_or(char *buf, int len, struct perf_pmu *pmu,
925 			     struct perf_pmu_alias *alias)
926 {
927 	snprintf(buf, len, "%s OR %s/%s/", alias->name, pmu->name, alias->name);
928 	return buf;
929 }
930 
931 static int cmp_string(const void *a, const void *b)
932 {
933 	const char * const *as = a;
934 	const char * const *bs = b;
935 	return strcmp(*as, *bs);
936 }
937 
938 void print_pmu_events(const char *event_glob, bool name_only)
939 {
940 	struct perf_pmu *pmu;
941 	struct perf_pmu_alias *alias;
942 	char buf[1024];
943 	int printed = 0;
944 	int len, j;
945 	char **aliases;
946 
947 	pmu = NULL;
948 	len = 0;
949 	while ((pmu = perf_pmu__scan(pmu)) != NULL) {
950 		list_for_each_entry(alias, &pmu->aliases, list)
951 			len++;
952 		if (pmu->selectable)
953 			len++;
954 	}
955 	aliases = zalloc(sizeof(char *) * len);
956 	if (!aliases)
957 		goto out_enomem;
958 	pmu = NULL;
959 	j = 0;
960 	while ((pmu = perf_pmu__scan(pmu)) != NULL) {
961 		list_for_each_entry(alias, &pmu->aliases, list) {
962 			char *name = format_alias(buf, sizeof(buf), pmu, alias);
963 			bool is_cpu = !strcmp(pmu->name, "cpu");
964 
965 			if (event_glob != NULL &&
966 			    !(strglobmatch(name, event_glob) ||
967 			      (!is_cpu && strglobmatch(alias->name,
968 						       event_glob))))
969 				continue;
970 
971 			if (is_cpu && !name_only)
972 				name = format_alias_or(buf, sizeof(buf), pmu, alias);
973 
974 			aliases[j] = strdup(name);
975 			if (aliases[j] == NULL)
976 				goto out_enomem;
977 			j++;
978 		}
979 		if (pmu->selectable) {
980 			char *s;
981 			if (asprintf(&s, "%s//", pmu->name) < 0)
982 				goto out_enomem;
983 			aliases[j] = s;
984 			j++;
985 		}
986 	}
987 	len = j;
988 	qsort(aliases, len, sizeof(char *), cmp_string);
989 	for (j = 0; j < len; j++) {
990 		if (name_only) {
991 			printf("%s ", aliases[j]);
992 			continue;
993 		}
994 		printf("  %-50s [Kernel PMU event]\n", aliases[j]);
995 		printed++;
996 	}
997 	if (printed)
998 		printf("\n");
999 out_free:
1000 	for (j = 0; j < len; j++)
1001 		zfree(&aliases[j]);
1002 	zfree(&aliases);
1003 	return;
1004 
1005 out_enomem:
1006 	printf("FATAL: not enough memory to print PMU events\n");
1007 	if (aliases)
1008 		goto out_free;
1009 }
1010 
1011 bool pmu_have_event(const char *pname, const char *name)
1012 {
1013 	struct perf_pmu *pmu;
1014 	struct perf_pmu_alias *alias;
1015 
1016 	pmu = NULL;
1017 	while ((pmu = perf_pmu__scan(pmu)) != NULL) {
1018 		if (strcmp(pname, pmu->name))
1019 			continue;
1020 		list_for_each_entry(alias, &pmu->aliases, list)
1021 			if (!strcmp(alias->name, name))
1022 				return true;
1023 	}
1024 	return false;
1025 }
1026 
1027 static FILE *perf_pmu__open_file(struct perf_pmu *pmu, const char *name)
1028 {
1029 	struct stat st;
1030 	char path[PATH_MAX];
1031 	const char *sysfs;
1032 
1033 	sysfs = sysfs__mountpoint();
1034 	if (!sysfs)
1035 		return NULL;
1036 
1037 	snprintf(path, PATH_MAX,
1038 		 "%s" EVENT_SOURCE_DEVICE_PATH "%s/%s", sysfs, pmu->name, name);
1039 
1040 	if (stat(path, &st) < 0)
1041 		return NULL;
1042 
1043 	return fopen(path, "r");
1044 }
1045 
1046 int perf_pmu__scan_file(struct perf_pmu *pmu, const char *name, const char *fmt,
1047 			...)
1048 {
1049 	va_list args;
1050 	FILE *file;
1051 	int ret = EOF;
1052 
1053 	va_start(args, fmt);
1054 	file = perf_pmu__open_file(pmu, name);
1055 	if (file) {
1056 		ret = vfscanf(file, fmt, args);
1057 		fclose(file);
1058 	}
1059 	va_end(args);
1060 	return ret;
1061 }
1062