xref: /openbmc/linux/tools/perf/util/pmu.c (revision 9a29ad52)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/list.h>
3 #include <linux/compiler.h>
4 #include <sys/types.h>
5 #include <errno.h>
6 #include <fcntl.h>
7 #include <sys/stat.h>
8 #include <unistd.h>
9 #include <stdio.h>
10 #include <stdbool.h>
11 #include <stdarg.h>
12 #include <dirent.h>
13 #include <api/fs/fs.h>
14 #include <locale.h>
15 #include <regex.h>
16 #include "util.h"
17 #include "pmu.h"
18 #include "parse-events.h"
19 #include "cpumap.h"
20 #include "header.h"
21 #include "pmu-events/pmu-events.h"
22 #include "cache.h"
23 #include "string2.h"
24 
25 struct perf_pmu_format {
26 	char *name;
27 	int value;
28 	DECLARE_BITMAP(bits, PERF_PMU_FORMAT_BITS);
29 	struct list_head list;
30 };
31 
32 #define EVENT_SOURCE_DEVICE_PATH "/bus/event_source/devices/"
33 
34 int perf_pmu_parse(struct list_head *list, char *name);
35 extern FILE *perf_pmu_in;
36 
37 static LIST_HEAD(pmus);
38 
39 /*
40  * Parse & process all the sysfs attributes located under
41  * the directory specified in 'dir' parameter.
42  */
43 int perf_pmu__format_parse(char *dir, struct list_head *head)
44 {
45 	struct dirent *evt_ent;
46 	DIR *format_dir;
47 	int ret = 0;
48 
49 	format_dir = opendir(dir);
50 	if (!format_dir)
51 		return -EINVAL;
52 
53 	while (!ret && (evt_ent = readdir(format_dir))) {
54 		char path[PATH_MAX];
55 		char *name = evt_ent->d_name;
56 		FILE *file;
57 
58 		if (!strcmp(name, ".") || !strcmp(name, ".."))
59 			continue;
60 
61 		snprintf(path, PATH_MAX, "%s/%s", dir, name);
62 
63 		ret = -EINVAL;
64 		file = fopen(path, "r");
65 		if (!file)
66 			break;
67 
68 		perf_pmu_in = file;
69 		ret = perf_pmu_parse(head, name);
70 		fclose(file);
71 	}
72 
73 	closedir(format_dir);
74 	return ret;
75 }
76 
77 /*
78  * Reading/parsing the default pmu format definition, which should be
79  * located at:
80  * /sys/bus/event_source/devices/<dev>/format as sysfs group attributes.
81  */
82 static int pmu_format(const char *name, struct list_head *format)
83 {
84 	struct stat st;
85 	char path[PATH_MAX];
86 	const char *sysfs = sysfs__mountpoint();
87 
88 	if (!sysfs)
89 		return -1;
90 
91 	snprintf(path, PATH_MAX,
92 		 "%s" EVENT_SOURCE_DEVICE_PATH "%s/format", sysfs, name);
93 
94 	if (stat(path, &st) < 0)
95 		return 0;	/* no error if format does not exist */
96 
97 	if (perf_pmu__format_parse(path, format))
98 		return -1;
99 
100 	return 0;
101 }
102 
103 static int convert_scale(const char *scale, char **end, double *sval)
104 {
105 	char *lc;
106 	int ret = 0;
107 
108 	/*
109 	 * save current locale
110 	 */
111 	lc = setlocale(LC_NUMERIC, NULL);
112 
113 	/*
114 	 * The lc string may be allocated in static storage,
115 	 * so get a dynamic copy to make it survive setlocale
116 	 * call below.
117 	 */
118 	lc = strdup(lc);
119 	if (!lc) {
120 		ret = -ENOMEM;
121 		goto out;
122 	}
123 
124 	/*
125 	 * force to C locale to ensure kernel
126 	 * scale string is converted correctly.
127 	 * kernel uses default C locale.
128 	 */
129 	setlocale(LC_NUMERIC, "C");
130 
131 	*sval = strtod(scale, end);
132 
133 out:
134 	/* restore locale */
135 	setlocale(LC_NUMERIC, lc);
136 	free(lc);
137 	return ret;
138 }
139 
140 static int perf_pmu__parse_scale(struct perf_pmu_alias *alias, char *dir, char *name)
141 {
142 	struct stat st;
143 	ssize_t sret;
144 	char scale[128];
145 	int fd, ret = -1;
146 	char path[PATH_MAX];
147 
148 	snprintf(path, PATH_MAX, "%s/%s.scale", dir, name);
149 
150 	fd = open(path, O_RDONLY);
151 	if (fd == -1)
152 		return -1;
153 
154 	if (fstat(fd, &st) < 0)
155 		goto error;
156 
157 	sret = read(fd, scale, sizeof(scale)-1);
158 	if (sret < 0)
159 		goto error;
160 
161 	if (scale[sret - 1] == '\n')
162 		scale[sret - 1] = '\0';
163 	else
164 		scale[sret] = '\0';
165 
166 	ret = convert_scale(scale, NULL, &alias->scale);
167 error:
168 	close(fd);
169 	return ret;
170 }
171 
172 static int perf_pmu__parse_unit(struct perf_pmu_alias *alias, char *dir, char *name)
173 {
174 	char path[PATH_MAX];
175 	ssize_t sret;
176 	int fd;
177 
178 	snprintf(path, PATH_MAX, "%s/%s.unit", dir, name);
179 
180 	fd = open(path, O_RDONLY);
181 	if (fd == -1)
182 		return -1;
183 
184 	sret = read(fd, alias->unit, UNIT_MAX_LEN);
185 	if (sret < 0)
186 		goto error;
187 
188 	close(fd);
189 
190 	if (alias->unit[sret - 1] == '\n')
191 		alias->unit[sret - 1] = '\0';
192 	else
193 		alias->unit[sret] = '\0';
194 
195 	return 0;
196 error:
197 	close(fd);
198 	alias->unit[0] = '\0';
199 	return -1;
200 }
201 
202 static int
203 perf_pmu__parse_per_pkg(struct perf_pmu_alias *alias, char *dir, char *name)
204 {
205 	char path[PATH_MAX];
206 	int fd;
207 
208 	snprintf(path, PATH_MAX, "%s/%s.per-pkg", dir, name);
209 
210 	fd = open(path, O_RDONLY);
211 	if (fd == -1)
212 		return -1;
213 
214 	close(fd);
215 
216 	alias->per_pkg = true;
217 	return 0;
218 }
219 
220 static int perf_pmu__parse_snapshot(struct perf_pmu_alias *alias,
221 				    char *dir, char *name)
222 {
223 	char path[PATH_MAX];
224 	int fd;
225 
226 	snprintf(path, PATH_MAX, "%s/%s.snapshot", dir, name);
227 
228 	fd = open(path, O_RDONLY);
229 	if (fd == -1)
230 		return -1;
231 
232 	alias->snapshot = true;
233 	close(fd);
234 	return 0;
235 }
236 
237 static void perf_pmu_assign_str(char *name, const char *field, char **old_str,
238 				char **new_str)
239 {
240 	if (!*old_str)
241 		goto set_new;
242 
243 	if (*new_str) {	/* Have new string, check with old */
244 		if (strcasecmp(*old_str, *new_str))
245 			pr_debug("alias %s differs in field '%s'\n",
246 				 name, field);
247 		zfree(old_str);
248 	} else		/* Nothing new --> keep old string */
249 		return;
250 set_new:
251 	*old_str = *new_str;
252 	*new_str = NULL;
253 }
254 
255 static void perf_pmu_update_alias(struct perf_pmu_alias *old,
256 				  struct perf_pmu_alias *newalias)
257 {
258 	perf_pmu_assign_str(old->name, "desc", &old->desc, &newalias->desc);
259 	perf_pmu_assign_str(old->name, "long_desc", &old->long_desc,
260 			    &newalias->long_desc);
261 	perf_pmu_assign_str(old->name, "topic", &old->topic, &newalias->topic);
262 	perf_pmu_assign_str(old->name, "metric_expr", &old->metric_expr,
263 			    &newalias->metric_expr);
264 	perf_pmu_assign_str(old->name, "metric_name", &old->metric_name,
265 			    &newalias->metric_name);
266 	perf_pmu_assign_str(old->name, "value", &old->str, &newalias->str);
267 	old->scale = newalias->scale;
268 	old->per_pkg = newalias->per_pkg;
269 	old->snapshot = newalias->snapshot;
270 	memcpy(old->unit, newalias->unit, sizeof(old->unit));
271 }
272 
273 /* Delete an alias entry. */
274 static void perf_pmu_free_alias(struct perf_pmu_alias *newalias)
275 {
276 	zfree(&newalias->name);
277 	zfree(&newalias->desc);
278 	zfree(&newalias->long_desc);
279 	zfree(&newalias->topic);
280 	zfree(&newalias->str);
281 	zfree(&newalias->metric_expr);
282 	zfree(&newalias->metric_name);
283 	parse_events_terms__purge(&newalias->terms);
284 	free(newalias);
285 }
286 
287 /* Merge an alias, search in alias list. If this name is already
288  * present merge both of them to combine all information.
289  */
290 static bool perf_pmu_merge_alias(struct perf_pmu_alias *newalias,
291 				 struct list_head *alist)
292 {
293 	struct perf_pmu_alias *a;
294 
295 	list_for_each_entry(a, alist, list) {
296 		if (!strcasecmp(newalias->name, a->name)) {
297 			perf_pmu_update_alias(a, newalias);
298 			perf_pmu_free_alias(newalias);
299 			return true;
300 		}
301 	}
302 	return false;
303 }
304 
305 static int __perf_pmu__new_alias(struct list_head *list, char *dir, char *name,
306 				 char *desc, char *val,
307 				 char *long_desc, char *topic,
308 				 char *unit, char *perpkg,
309 				 char *metric_expr,
310 				 char *metric_name)
311 {
312 	struct parse_events_term *term;
313 	struct perf_pmu_alias *alias;
314 	int ret;
315 	int num;
316 	char newval[256];
317 
318 	alias = malloc(sizeof(*alias));
319 	if (!alias)
320 		return -ENOMEM;
321 
322 	INIT_LIST_HEAD(&alias->terms);
323 	alias->scale = 1.0;
324 	alias->unit[0] = '\0';
325 	alias->per_pkg = false;
326 	alias->snapshot = false;
327 
328 	ret = parse_events_terms(&alias->terms, val);
329 	if (ret) {
330 		pr_err("Cannot parse alias %s: %d\n", val, ret);
331 		free(alias);
332 		return ret;
333 	}
334 
335 	/* Scan event and remove leading zeroes, spaces, newlines, some
336 	 * platforms have terms specified as
337 	 * event=0x0091 (read from files ../<PMU>/events/<FILE>
338 	 * and terms specified as event=0x91 (read from JSON files).
339 	 *
340 	 * Rebuild string to make alias->str member comparable.
341 	 */
342 	memset(newval, 0, sizeof(newval));
343 	ret = 0;
344 	list_for_each_entry(term, &alias->terms, list) {
345 		if (ret)
346 			ret += scnprintf(newval + ret, sizeof(newval) - ret,
347 					 ",");
348 		if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM)
349 			ret += scnprintf(newval + ret, sizeof(newval) - ret,
350 					 "%s=%#x", term->config, term->val.num);
351 		else if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR)
352 			ret += scnprintf(newval + ret, sizeof(newval) - ret,
353 					 "%s=%s", term->config, term->val.str);
354 	}
355 
356 	alias->name = strdup(name);
357 	if (dir) {
358 		/*
359 		 * load unit name and scale if available
360 		 */
361 		perf_pmu__parse_unit(alias, dir, name);
362 		perf_pmu__parse_scale(alias, dir, name);
363 		perf_pmu__parse_per_pkg(alias, dir, name);
364 		perf_pmu__parse_snapshot(alias, dir, name);
365 	}
366 
367 	alias->metric_expr = metric_expr ? strdup(metric_expr) : NULL;
368 	alias->metric_name = metric_name ? strdup(metric_name): NULL;
369 	alias->desc = desc ? strdup(desc) : NULL;
370 	alias->long_desc = long_desc ? strdup(long_desc) :
371 				desc ? strdup(desc) : NULL;
372 	alias->topic = topic ? strdup(topic) : NULL;
373 	if (unit) {
374 		if (convert_scale(unit, &unit, &alias->scale) < 0)
375 			return -1;
376 		snprintf(alias->unit, sizeof(alias->unit), "%s", unit);
377 	}
378 	alias->per_pkg = perpkg && sscanf(perpkg, "%d", &num) == 1 && num == 1;
379 	alias->str = strdup(newval);
380 
381 	if (!perf_pmu_merge_alias(alias, list))
382 		list_add_tail(&alias->list, list);
383 
384 	return 0;
385 }
386 
387 static int perf_pmu__new_alias(struct list_head *list, char *dir, char *name, FILE *file)
388 {
389 	char buf[256];
390 	int ret;
391 
392 	ret = fread(buf, 1, sizeof(buf), file);
393 	if (ret == 0)
394 		return -EINVAL;
395 
396 	buf[ret] = 0;
397 
398 	/* Remove trailing newline from sysfs file */
399 	rtrim(buf);
400 
401 	return __perf_pmu__new_alias(list, dir, name, NULL, buf, NULL, NULL, NULL,
402 				     NULL, NULL, NULL);
403 }
404 
405 static inline bool pmu_alias_info_file(char *name)
406 {
407 	size_t len;
408 
409 	len = strlen(name);
410 	if (len > 5 && !strcmp(name + len - 5, ".unit"))
411 		return true;
412 	if (len > 6 && !strcmp(name + len - 6, ".scale"))
413 		return true;
414 	if (len > 8 && !strcmp(name + len - 8, ".per-pkg"))
415 		return true;
416 	if (len > 9 && !strcmp(name + len - 9, ".snapshot"))
417 		return true;
418 
419 	return false;
420 }
421 
422 /*
423  * Process all the sysfs attributes located under the directory
424  * specified in 'dir' parameter.
425  */
426 static int pmu_aliases_parse(char *dir, struct list_head *head)
427 {
428 	struct dirent *evt_ent;
429 	DIR *event_dir;
430 
431 	event_dir = opendir(dir);
432 	if (!event_dir)
433 		return -EINVAL;
434 
435 	while ((evt_ent = readdir(event_dir))) {
436 		char path[PATH_MAX];
437 		char *name = evt_ent->d_name;
438 		FILE *file;
439 
440 		if (!strcmp(name, ".") || !strcmp(name, ".."))
441 			continue;
442 
443 		/*
444 		 * skip info files parsed in perf_pmu__new_alias()
445 		 */
446 		if (pmu_alias_info_file(name))
447 			continue;
448 
449 		scnprintf(path, PATH_MAX, "%s/%s", dir, name);
450 
451 		file = fopen(path, "r");
452 		if (!file) {
453 			pr_debug("Cannot open %s\n", path);
454 			continue;
455 		}
456 
457 		if (perf_pmu__new_alias(head, dir, name, file) < 0)
458 			pr_debug("Cannot set up %s\n", name);
459 		fclose(file);
460 	}
461 
462 	closedir(event_dir);
463 	return 0;
464 }
465 
466 /*
467  * Reading the pmu event aliases definition, which should be located at:
468  * /sys/bus/event_source/devices/<dev>/events as sysfs group attributes.
469  */
470 static int pmu_aliases(const char *name, struct list_head *head)
471 {
472 	struct stat st;
473 	char path[PATH_MAX];
474 	const char *sysfs = sysfs__mountpoint();
475 
476 	if (!sysfs)
477 		return -1;
478 
479 	snprintf(path, PATH_MAX,
480 		 "%s/bus/event_source/devices/%s/events", sysfs, name);
481 
482 	if (stat(path, &st) < 0)
483 		return 0;	 /* no error if 'events' does not exist */
484 
485 	if (pmu_aliases_parse(path, head))
486 		return -1;
487 
488 	return 0;
489 }
490 
491 static int pmu_alias_terms(struct perf_pmu_alias *alias,
492 			   struct list_head *terms)
493 {
494 	struct parse_events_term *term, *cloned;
495 	LIST_HEAD(list);
496 	int ret;
497 
498 	list_for_each_entry(term, &alias->terms, list) {
499 		ret = parse_events_term__clone(&cloned, term);
500 		if (ret) {
501 			parse_events_terms__purge(&list);
502 			return ret;
503 		}
504 		/*
505 		 * Weak terms don't override command line options,
506 		 * which we don't want for implicit terms in aliases.
507 		 */
508 		cloned->weak = true;
509 		list_add_tail(&cloned->list, &list);
510 	}
511 	list_splice(&list, terms);
512 	return 0;
513 }
514 
515 /*
516  * Reading/parsing the default pmu type value, which should be
517  * located at:
518  * /sys/bus/event_source/devices/<dev>/type as sysfs attribute.
519  */
520 static int pmu_type(const char *name, __u32 *type)
521 {
522 	struct stat st;
523 	char path[PATH_MAX];
524 	FILE *file;
525 	int ret = 0;
526 	const char *sysfs = sysfs__mountpoint();
527 
528 	if (!sysfs)
529 		return -1;
530 
531 	snprintf(path, PATH_MAX,
532 		 "%s" EVENT_SOURCE_DEVICE_PATH "%s/type", sysfs, name);
533 
534 	if (stat(path, &st) < 0)
535 		return -1;
536 
537 	file = fopen(path, "r");
538 	if (!file)
539 		return -EINVAL;
540 
541 	if (1 != fscanf(file, "%u", type))
542 		ret = -1;
543 
544 	fclose(file);
545 	return ret;
546 }
547 
548 /* Add all pmus in sysfs to pmu list: */
549 static void pmu_read_sysfs(void)
550 {
551 	char path[PATH_MAX];
552 	DIR *dir;
553 	struct dirent *dent;
554 	const char *sysfs = sysfs__mountpoint();
555 
556 	if (!sysfs)
557 		return;
558 
559 	snprintf(path, PATH_MAX,
560 		 "%s" EVENT_SOURCE_DEVICE_PATH, sysfs);
561 
562 	dir = opendir(path);
563 	if (!dir)
564 		return;
565 
566 	while ((dent = readdir(dir))) {
567 		if (!strcmp(dent->d_name, ".") || !strcmp(dent->d_name, ".."))
568 			continue;
569 		/* add to static LIST_HEAD(pmus): */
570 		perf_pmu__find(dent->d_name);
571 	}
572 
573 	closedir(dir);
574 }
575 
576 static struct cpu_map *__pmu_cpumask(const char *path)
577 {
578 	FILE *file;
579 	struct cpu_map *cpus;
580 
581 	file = fopen(path, "r");
582 	if (!file)
583 		return NULL;
584 
585 	cpus = cpu_map__read(file);
586 	fclose(file);
587 	return cpus;
588 }
589 
590 /*
591  * Uncore PMUs have a "cpumask" file under sysfs. CPU PMUs (e.g. on arm/arm64)
592  * may have a "cpus" file.
593  */
594 #define CPUS_TEMPLATE_UNCORE	"%s/bus/event_source/devices/%s/cpumask"
595 #define CPUS_TEMPLATE_CPU	"%s/bus/event_source/devices/%s/cpus"
596 
597 static struct cpu_map *pmu_cpumask(const char *name)
598 {
599 	char path[PATH_MAX];
600 	struct cpu_map *cpus;
601 	const char *sysfs = sysfs__mountpoint();
602 	const char *templates[] = {
603 		CPUS_TEMPLATE_UNCORE,
604 		CPUS_TEMPLATE_CPU,
605 		NULL
606 	};
607 	const char **template;
608 
609 	if (!sysfs)
610 		return NULL;
611 
612 	for (template = templates; *template; template++) {
613 		snprintf(path, PATH_MAX, *template, sysfs, name);
614 		cpus = __pmu_cpumask(path);
615 		if (cpus)
616 			return cpus;
617 	}
618 
619 	return NULL;
620 }
621 
622 static bool pmu_is_uncore(const char *name)
623 {
624 	char path[PATH_MAX];
625 	struct cpu_map *cpus;
626 	const char *sysfs = sysfs__mountpoint();
627 
628 	snprintf(path, PATH_MAX, CPUS_TEMPLATE_UNCORE, sysfs, name);
629 	cpus = __pmu_cpumask(path);
630 	cpu_map__put(cpus);
631 
632 	return !!cpus;
633 }
634 
635 /*
636  *  PMU CORE devices have different name other than cpu in sysfs on some
637  *  platforms.
638  *  Looking for possible sysfs files to identify the arm core device.
639  */
640 static int is_arm_pmu_core(const char *name)
641 {
642 	struct stat st;
643 	char path[PATH_MAX];
644 	const char *sysfs = sysfs__mountpoint();
645 
646 	if (!sysfs)
647 		return 0;
648 
649 	/* Look for cpu sysfs (specific to arm) */
650 	scnprintf(path, PATH_MAX, "%s/bus/event_source/devices/%s/cpus",
651 				sysfs, name);
652 	if (stat(path, &st) == 0)
653 		return 1;
654 
655 	/* Look for cpu sysfs (specific to s390) */
656 	scnprintf(path, PATH_MAX, "%s/bus/event_source/devices/%s",
657 		  sysfs, name);
658 	if (stat(path, &st) == 0 && !strncmp(name, "cpum_", 5))
659 		return 1;
660 
661 	return 0;
662 }
663 
664 /*
665  * Return the CPU id as a raw string.
666  *
667  * Each architecture should provide a more precise id string that
668  * can be use to match the architecture's "mapfile".
669  */
670 char * __weak get_cpuid_str(struct perf_pmu *pmu __maybe_unused)
671 {
672 	return NULL;
673 }
674 
675 /* Return zero when the cpuid from the mapfile.csv matches the
676  * cpuid string generated on this platform.
677  * Otherwise return non-zero.
678  */
679 int strcmp_cpuid_str(const char *mapcpuid, const char *cpuid)
680 {
681 	regex_t re;
682 	regmatch_t pmatch[1];
683 	int match;
684 
685 	if (regcomp(&re, mapcpuid, REG_EXTENDED) != 0) {
686 		/* Warn unable to generate match particular string. */
687 		pr_info("Invalid regular expression %s\n", mapcpuid);
688 		return 1;
689 	}
690 
691 	match = !regexec(&re, cpuid, 1, pmatch, 0);
692 	regfree(&re);
693 	if (match) {
694 		size_t match_len = (pmatch[0].rm_eo - pmatch[0].rm_so);
695 
696 		/* Verify the entire string matched. */
697 		if (match_len == strlen(cpuid))
698 			return 0;
699 	}
700 	return 1;
701 }
702 
703 static char *perf_pmu__getcpuid(struct perf_pmu *pmu)
704 {
705 	char *cpuid;
706 	static bool printed;
707 
708 	cpuid = getenv("PERF_CPUID");
709 	if (cpuid)
710 		cpuid = strdup(cpuid);
711 	if (!cpuid)
712 		cpuid = get_cpuid_str(pmu);
713 	if (!cpuid)
714 		return NULL;
715 
716 	if (!printed) {
717 		pr_debug("Using CPUID %s\n", cpuid);
718 		printed = true;
719 	}
720 	return cpuid;
721 }
722 
723 struct pmu_events_map *perf_pmu__find_map(struct perf_pmu *pmu)
724 {
725 	struct pmu_events_map *map;
726 	char *cpuid = perf_pmu__getcpuid(pmu);
727 	int i;
728 
729 	/* on some platforms which uses cpus map, cpuid can be NULL for
730 	 * PMUs other than CORE PMUs.
731 	 */
732 	if (!cpuid)
733 		return NULL;
734 
735 	i = 0;
736 	for (;;) {
737 		map = &pmu_events_map[i++];
738 		if (!map->table) {
739 			map = NULL;
740 			break;
741 		}
742 
743 		if (!strcmp_cpuid_str(map->cpuid, cpuid))
744 			break;
745 	}
746 	free(cpuid);
747 	return map;
748 }
749 
750 /*
751  * From the pmu_events_map, find the table of PMU events that corresponds
752  * to the current running CPU. Then, add all PMU events from that table
753  * as aliases.
754  */
755 static void pmu_add_cpu_aliases(struct list_head *head, struct perf_pmu *pmu)
756 {
757 	int i;
758 	struct pmu_events_map *map;
759 	struct pmu_event *pe;
760 	const char *name = pmu->name;
761 	const char *pname;
762 
763 	map = perf_pmu__find_map(pmu);
764 	if (!map)
765 		return;
766 
767 	/*
768 	 * Found a matching PMU events table. Create aliases
769 	 */
770 	i = 0;
771 	while (1) {
772 
773 		pe = &map->table[i++];
774 		if (!pe->name) {
775 			if (pe->metric_group || pe->metric_name)
776 				continue;
777 			break;
778 		}
779 
780 		if (!is_arm_pmu_core(name)) {
781 			pname = pe->pmu ? pe->pmu : "cpu";
782 			if (strncmp(pname, name, strlen(pname)))
783 				continue;
784 		}
785 
786 		/* need type casts to override 'const' */
787 		__perf_pmu__new_alias(head, NULL, (char *)pe->name,
788 				(char *)pe->desc, (char *)pe->event,
789 				(char *)pe->long_desc, (char *)pe->topic,
790 				(char *)pe->unit, (char *)pe->perpkg,
791 				(char *)pe->metric_expr,
792 				(char *)pe->metric_name);
793 	}
794 }
795 
796 struct perf_event_attr * __weak
797 perf_pmu__get_default_config(struct perf_pmu *pmu __maybe_unused)
798 {
799 	return NULL;
800 }
801 
802 static struct perf_pmu *pmu_lookup(const char *name)
803 {
804 	struct perf_pmu *pmu;
805 	LIST_HEAD(format);
806 	LIST_HEAD(aliases);
807 	__u32 type;
808 
809 	/*
810 	 * The pmu data we store & need consists of the pmu
811 	 * type value and format definitions. Load both right
812 	 * now.
813 	 */
814 	if (pmu_format(name, &format))
815 		return NULL;
816 
817 	/*
818 	 * Check the type first to avoid unnecessary work.
819 	 */
820 	if (pmu_type(name, &type))
821 		return NULL;
822 
823 	if (pmu_aliases(name, &aliases))
824 		return NULL;
825 
826 	pmu = zalloc(sizeof(*pmu));
827 	if (!pmu)
828 		return NULL;
829 
830 	pmu->cpus = pmu_cpumask(name);
831 	pmu->name = strdup(name);
832 	pmu->type = type;
833 	pmu->is_uncore = pmu_is_uncore(name);
834 	pmu_add_cpu_aliases(&aliases, pmu);
835 
836 	INIT_LIST_HEAD(&pmu->format);
837 	INIT_LIST_HEAD(&pmu->aliases);
838 	list_splice(&format, &pmu->format);
839 	list_splice(&aliases, &pmu->aliases);
840 	list_add_tail(&pmu->list, &pmus);
841 
842 	pmu->default_config = perf_pmu__get_default_config(pmu);
843 
844 	return pmu;
845 }
846 
847 static struct perf_pmu *pmu_find(const char *name)
848 {
849 	struct perf_pmu *pmu;
850 
851 	list_for_each_entry(pmu, &pmus, list)
852 		if (!strcmp(pmu->name, name))
853 			return pmu;
854 
855 	return NULL;
856 }
857 
858 struct perf_pmu *perf_pmu__scan(struct perf_pmu *pmu)
859 {
860 	/*
861 	 * pmu iterator: If pmu is NULL, we start at the begin,
862 	 * otherwise return the next pmu. Returns NULL on end.
863 	 */
864 	if (!pmu) {
865 		pmu_read_sysfs();
866 		pmu = list_prepare_entry(pmu, &pmus, list);
867 	}
868 	list_for_each_entry_continue(pmu, &pmus, list)
869 		return pmu;
870 	return NULL;
871 }
872 
873 struct perf_pmu *perf_pmu__find(const char *name)
874 {
875 	struct perf_pmu *pmu;
876 
877 	/*
878 	 * Once PMU is loaded it stays in the list,
879 	 * so we keep us from multiple reading/parsing
880 	 * the pmu format definitions.
881 	 */
882 	pmu = pmu_find(name);
883 	if (pmu)
884 		return pmu;
885 
886 	return pmu_lookup(name);
887 }
888 
889 static struct perf_pmu_format *
890 pmu_find_format(struct list_head *formats, const char *name)
891 {
892 	struct perf_pmu_format *format;
893 
894 	list_for_each_entry(format, formats, list)
895 		if (!strcmp(format->name, name))
896 			return format;
897 
898 	return NULL;
899 }
900 
901 __u64 perf_pmu__format_bits(struct list_head *formats, const char *name)
902 {
903 	struct perf_pmu_format *format = pmu_find_format(formats, name);
904 	__u64 bits = 0;
905 	int fbit;
906 
907 	if (!format)
908 		return 0;
909 
910 	for_each_set_bit(fbit, format->bits, PERF_PMU_FORMAT_BITS)
911 		bits |= 1ULL << fbit;
912 
913 	return bits;
914 }
915 
916 /*
917  * Sets value based on the format definition (format parameter)
918  * and unformated value (value parameter).
919  */
920 static void pmu_format_value(unsigned long *format, __u64 value, __u64 *v,
921 			     bool zero)
922 {
923 	unsigned long fbit, vbit;
924 
925 	for (fbit = 0, vbit = 0; fbit < PERF_PMU_FORMAT_BITS; fbit++) {
926 
927 		if (!test_bit(fbit, format))
928 			continue;
929 
930 		if (value & (1llu << vbit++))
931 			*v |= (1llu << fbit);
932 		else if (zero)
933 			*v &= ~(1llu << fbit);
934 	}
935 }
936 
937 static __u64 pmu_format_max_value(const unsigned long *format)
938 {
939 	__u64 w = 0;
940 	int fbit;
941 
942 	for_each_set_bit(fbit, format, PERF_PMU_FORMAT_BITS)
943 		w |= (1ULL << fbit);
944 
945 	return w;
946 }
947 
948 /*
949  * Term is a string term, and might be a param-term. Try to look up it's value
950  * in the remaining terms.
951  * - We have a term like "base-or-format-term=param-term",
952  * - We need to find the value supplied for "param-term" (with param-term named
953  *   in a config string) later on in the term list.
954  */
955 static int pmu_resolve_param_term(struct parse_events_term *term,
956 				  struct list_head *head_terms,
957 				  __u64 *value)
958 {
959 	struct parse_events_term *t;
960 
961 	list_for_each_entry(t, head_terms, list) {
962 		if (t->type_val == PARSE_EVENTS__TERM_TYPE_NUM) {
963 			if (!strcmp(t->config, term->config)) {
964 				t->used = true;
965 				*value = t->val.num;
966 				return 0;
967 			}
968 		}
969 	}
970 
971 	if (verbose > 0)
972 		printf("Required parameter '%s' not specified\n", term->config);
973 
974 	return -1;
975 }
976 
977 static char *pmu_formats_string(struct list_head *formats)
978 {
979 	struct perf_pmu_format *format;
980 	char *str = NULL;
981 	struct strbuf buf = STRBUF_INIT;
982 	unsigned i = 0;
983 
984 	if (!formats)
985 		return NULL;
986 
987 	/* sysfs exported terms */
988 	list_for_each_entry(format, formats, list)
989 		if (strbuf_addf(&buf, i++ ? ",%s" : "%s", format->name) < 0)
990 			goto error;
991 
992 	str = strbuf_detach(&buf, NULL);
993 error:
994 	strbuf_release(&buf);
995 
996 	return str;
997 }
998 
999 /*
1000  * Setup one of config[12] attr members based on the
1001  * user input data - term parameter.
1002  */
1003 static int pmu_config_term(struct list_head *formats,
1004 			   struct perf_event_attr *attr,
1005 			   struct parse_events_term *term,
1006 			   struct list_head *head_terms,
1007 			   bool zero, struct parse_events_error *err)
1008 {
1009 	struct perf_pmu_format *format;
1010 	__u64 *vp;
1011 	__u64 val, max_val;
1012 
1013 	/*
1014 	 * If this is a parameter we've already used for parameterized-eval,
1015 	 * skip it in normal eval.
1016 	 */
1017 	if (term->used)
1018 		return 0;
1019 
1020 	/*
1021 	 * Hardcoded terms should be already in, so nothing
1022 	 * to be done for them.
1023 	 */
1024 	if (parse_events__is_hardcoded_term(term))
1025 		return 0;
1026 
1027 	format = pmu_find_format(formats, term->config);
1028 	if (!format) {
1029 		if (verbose > 0)
1030 			printf("Invalid event/parameter '%s'\n", term->config);
1031 		if (err) {
1032 			char *pmu_term = pmu_formats_string(formats);
1033 
1034 			err->idx  = term->err_term;
1035 			err->str  = strdup("unknown term");
1036 			err->help = parse_events_formats_error_string(pmu_term);
1037 			free(pmu_term);
1038 		}
1039 		return -EINVAL;
1040 	}
1041 
1042 	switch (format->value) {
1043 	case PERF_PMU_FORMAT_VALUE_CONFIG:
1044 		vp = &attr->config;
1045 		break;
1046 	case PERF_PMU_FORMAT_VALUE_CONFIG1:
1047 		vp = &attr->config1;
1048 		break;
1049 	case PERF_PMU_FORMAT_VALUE_CONFIG2:
1050 		vp = &attr->config2;
1051 		break;
1052 	default:
1053 		return -EINVAL;
1054 	}
1055 
1056 	/*
1057 	 * Either directly use a numeric term, or try to translate string terms
1058 	 * using event parameters.
1059 	 */
1060 	if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM) {
1061 		if (term->no_value &&
1062 		    bitmap_weight(format->bits, PERF_PMU_FORMAT_BITS) > 1) {
1063 			if (err) {
1064 				err->idx = term->err_val;
1065 				err->str = strdup("no value assigned for term");
1066 			}
1067 			return -EINVAL;
1068 		}
1069 
1070 		val = term->val.num;
1071 	} else if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR) {
1072 		if (strcmp(term->val.str, "?")) {
1073 			if (verbose > 0) {
1074 				pr_info("Invalid sysfs entry %s=%s\n",
1075 						term->config, term->val.str);
1076 			}
1077 			if (err) {
1078 				err->idx = term->err_val;
1079 				err->str = strdup("expected numeric value");
1080 			}
1081 			return -EINVAL;
1082 		}
1083 
1084 		if (pmu_resolve_param_term(term, head_terms, &val))
1085 			return -EINVAL;
1086 	} else
1087 		return -EINVAL;
1088 
1089 	max_val = pmu_format_max_value(format->bits);
1090 	if (val > max_val) {
1091 		if (err) {
1092 			err->idx = term->err_val;
1093 			if (asprintf(&err->str,
1094 				     "value too big for format, maximum is %llu",
1095 				     (unsigned long long)max_val) < 0)
1096 				err->str = strdup("value too big for format");
1097 			return -EINVAL;
1098 		}
1099 		/*
1100 		 * Assume we don't care if !err, in which case the value will be
1101 		 * silently truncated.
1102 		 */
1103 	}
1104 
1105 	pmu_format_value(format->bits, val, vp, zero);
1106 	return 0;
1107 }
1108 
1109 int perf_pmu__config_terms(struct list_head *formats,
1110 			   struct perf_event_attr *attr,
1111 			   struct list_head *head_terms,
1112 			   bool zero, struct parse_events_error *err)
1113 {
1114 	struct parse_events_term *term;
1115 
1116 	list_for_each_entry(term, head_terms, list) {
1117 		if (pmu_config_term(formats, attr, term, head_terms,
1118 				    zero, err))
1119 			return -EINVAL;
1120 	}
1121 
1122 	return 0;
1123 }
1124 
1125 /*
1126  * Configures event's 'attr' parameter based on the:
1127  * 1) users input - specified in terms parameter
1128  * 2) pmu format definitions - specified by pmu parameter
1129  */
1130 int perf_pmu__config(struct perf_pmu *pmu, struct perf_event_attr *attr,
1131 		     struct list_head *head_terms,
1132 		     struct parse_events_error *err)
1133 {
1134 	bool zero = !!pmu->default_config;
1135 
1136 	attr->type = pmu->type;
1137 	return perf_pmu__config_terms(&pmu->format, attr, head_terms,
1138 				      zero, err);
1139 }
1140 
1141 static struct perf_pmu_alias *pmu_find_alias(struct perf_pmu *pmu,
1142 					     struct parse_events_term *term)
1143 {
1144 	struct perf_pmu_alias *alias;
1145 	char *name;
1146 
1147 	if (parse_events__is_hardcoded_term(term))
1148 		return NULL;
1149 
1150 	if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM) {
1151 		if (term->val.num != 1)
1152 			return NULL;
1153 		if (pmu_find_format(&pmu->format, term->config))
1154 			return NULL;
1155 		name = term->config;
1156 	} else if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR) {
1157 		if (strcasecmp(term->config, "event"))
1158 			return NULL;
1159 		name = term->val.str;
1160 	} else {
1161 		return NULL;
1162 	}
1163 
1164 	list_for_each_entry(alias, &pmu->aliases, list) {
1165 		if (!strcasecmp(alias->name, name))
1166 			return alias;
1167 	}
1168 	return NULL;
1169 }
1170 
1171 
1172 static int check_info_data(struct perf_pmu_alias *alias,
1173 			   struct perf_pmu_info *info)
1174 {
1175 	/*
1176 	 * Only one term in event definition can
1177 	 * define unit, scale and snapshot, fail
1178 	 * if there's more than one.
1179 	 */
1180 	if ((info->unit && alias->unit[0]) ||
1181 	    (info->scale && alias->scale) ||
1182 	    (info->snapshot && alias->snapshot))
1183 		return -EINVAL;
1184 
1185 	if (alias->unit[0])
1186 		info->unit = alias->unit;
1187 
1188 	if (alias->scale)
1189 		info->scale = alias->scale;
1190 
1191 	if (alias->snapshot)
1192 		info->snapshot = alias->snapshot;
1193 
1194 	return 0;
1195 }
1196 
1197 /*
1198  * Find alias in the terms list and replace it with the terms
1199  * defined for the alias
1200  */
1201 int perf_pmu__check_alias(struct perf_pmu *pmu, struct list_head *head_terms,
1202 			  struct perf_pmu_info *info)
1203 {
1204 	struct parse_events_term *term, *h;
1205 	struct perf_pmu_alias *alias;
1206 	int ret;
1207 
1208 	info->per_pkg = false;
1209 
1210 	/*
1211 	 * Mark unit and scale as not set
1212 	 * (different from default values, see below)
1213 	 */
1214 	info->unit     = NULL;
1215 	info->scale    = 0.0;
1216 	info->snapshot = false;
1217 	info->metric_expr = NULL;
1218 	info->metric_name = NULL;
1219 
1220 	list_for_each_entry_safe(term, h, head_terms, list) {
1221 		alias = pmu_find_alias(pmu, term);
1222 		if (!alias)
1223 			continue;
1224 		ret = pmu_alias_terms(alias, &term->list);
1225 		if (ret)
1226 			return ret;
1227 
1228 		ret = check_info_data(alias, info);
1229 		if (ret)
1230 			return ret;
1231 
1232 		if (alias->per_pkg)
1233 			info->per_pkg = true;
1234 		info->metric_expr = alias->metric_expr;
1235 		info->metric_name = alias->metric_name;
1236 
1237 		list_del(&term->list);
1238 		free(term);
1239 	}
1240 
1241 	/*
1242 	 * if no unit or scale foundin aliases, then
1243 	 * set defaults as for evsel
1244 	 * unit cannot left to NULL
1245 	 */
1246 	if (info->unit == NULL)
1247 		info->unit   = "";
1248 
1249 	if (info->scale == 0.0)
1250 		info->scale  = 1.0;
1251 
1252 	return 0;
1253 }
1254 
1255 int perf_pmu__new_format(struct list_head *list, char *name,
1256 			 int config, unsigned long *bits)
1257 {
1258 	struct perf_pmu_format *format;
1259 
1260 	format = zalloc(sizeof(*format));
1261 	if (!format)
1262 		return -ENOMEM;
1263 
1264 	format->name = strdup(name);
1265 	format->value = config;
1266 	memcpy(format->bits, bits, sizeof(format->bits));
1267 
1268 	list_add_tail(&format->list, list);
1269 	return 0;
1270 }
1271 
1272 void perf_pmu__set_format(unsigned long *bits, long from, long to)
1273 {
1274 	long b;
1275 
1276 	if (!to)
1277 		to = from;
1278 
1279 	memset(bits, 0, BITS_TO_BYTES(PERF_PMU_FORMAT_BITS));
1280 	for (b = from; b <= to; b++)
1281 		set_bit(b, bits);
1282 }
1283 
1284 static int sub_non_neg(int a, int b)
1285 {
1286 	if (b > a)
1287 		return 0;
1288 	return a - b;
1289 }
1290 
1291 static char *format_alias(char *buf, int len, struct perf_pmu *pmu,
1292 			  struct perf_pmu_alias *alias)
1293 {
1294 	struct parse_events_term *term;
1295 	int used = snprintf(buf, len, "%s/%s", pmu->name, alias->name);
1296 
1297 	list_for_each_entry(term, &alias->terms, list) {
1298 		if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR)
1299 			used += snprintf(buf + used, sub_non_neg(len, used),
1300 					",%s=%s", term->config,
1301 					term->val.str);
1302 	}
1303 
1304 	if (sub_non_neg(len, used) > 0) {
1305 		buf[used] = '/';
1306 		used++;
1307 	}
1308 	if (sub_non_neg(len, used) > 0) {
1309 		buf[used] = '\0';
1310 		used++;
1311 	} else
1312 		buf[len - 1] = '\0';
1313 
1314 	return buf;
1315 }
1316 
1317 static char *format_alias_or(char *buf, int len, struct perf_pmu *pmu,
1318 			     struct perf_pmu_alias *alias)
1319 {
1320 	snprintf(buf, len, "%s OR %s/%s/", alias->name, pmu->name, alias->name);
1321 	return buf;
1322 }
1323 
1324 struct sevent {
1325 	char *name;
1326 	char *desc;
1327 	char *topic;
1328 	char *str;
1329 	char *pmu;
1330 	char *metric_expr;
1331 	char *metric_name;
1332 };
1333 
1334 static int cmp_sevent(const void *a, const void *b)
1335 {
1336 	const struct sevent *as = a;
1337 	const struct sevent *bs = b;
1338 
1339 	/* Put extra events last */
1340 	if (!!as->desc != !!bs->desc)
1341 		return !!as->desc - !!bs->desc;
1342 	if (as->topic && bs->topic) {
1343 		int n = strcmp(as->topic, bs->topic);
1344 
1345 		if (n)
1346 			return n;
1347 	}
1348 	return strcmp(as->name, bs->name);
1349 }
1350 
1351 static void wordwrap(char *s, int start, int max, int corr)
1352 {
1353 	int column = start;
1354 	int n;
1355 
1356 	while (*s) {
1357 		int wlen = strcspn(s, " \t");
1358 
1359 		if (column + wlen >= max && column > start) {
1360 			printf("\n%*s", start, "");
1361 			column = start + corr;
1362 		}
1363 		n = printf("%s%.*s", column > start ? " " : "", wlen, s);
1364 		if (n <= 0)
1365 			break;
1366 		s += wlen;
1367 		column += n;
1368 		s = ltrim(s);
1369 	}
1370 }
1371 
1372 void print_pmu_events(const char *event_glob, bool name_only, bool quiet_flag,
1373 			bool long_desc, bool details_flag)
1374 {
1375 	struct perf_pmu *pmu;
1376 	struct perf_pmu_alias *alias;
1377 	char buf[1024];
1378 	int printed = 0;
1379 	int len, j;
1380 	struct sevent *aliases;
1381 	int numdesc = 0;
1382 	int columns = pager_get_columns();
1383 	char *topic = NULL;
1384 
1385 	pmu = NULL;
1386 	len = 0;
1387 	while ((pmu = perf_pmu__scan(pmu)) != NULL) {
1388 		list_for_each_entry(alias, &pmu->aliases, list)
1389 			len++;
1390 		if (pmu->selectable)
1391 			len++;
1392 	}
1393 	aliases = zalloc(sizeof(struct sevent) * len);
1394 	if (!aliases)
1395 		goto out_enomem;
1396 	pmu = NULL;
1397 	j = 0;
1398 	while ((pmu = perf_pmu__scan(pmu)) != NULL) {
1399 		list_for_each_entry(alias, &pmu->aliases, list) {
1400 			char *name = alias->desc ? alias->name :
1401 				format_alias(buf, sizeof(buf), pmu, alias);
1402 			bool is_cpu = !strcmp(pmu->name, "cpu");
1403 
1404 			if (event_glob != NULL &&
1405 			    !(strglobmatch_nocase(name, event_glob) ||
1406 			      (!is_cpu && strglobmatch_nocase(alias->name,
1407 						       event_glob)) ||
1408 			      (alias->topic &&
1409 			       strglobmatch_nocase(alias->topic, event_glob))))
1410 				continue;
1411 
1412 			if (is_cpu && !name_only && !alias->desc)
1413 				name = format_alias_or(buf, sizeof(buf), pmu, alias);
1414 
1415 			aliases[j].name = name;
1416 			if (is_cpu && !name_only && !alias->desc)
1417 				aliases[j].name = format_alias_or(buf,
1418 								  sizeof(buf),
1419 								  pmu, alias);
1420 			aliases[j].name = strdup(aliases[j].name);
1421 			if (!aliases[j].name)
1422 				goto out_enomem;
1423 
1424 			aliases[j].desc = long_desc ? alias->long_desc :
1425 						alias->desc;
1426 			aliases[j].topic = alias->topic;
1427 			aliases[j].str = alias->str;
1428 			aliases[j].pmu = pmu->name;
1429 			aliases[j].metric_expr = alias->metric_expr;
1430 			aliases[j].metric_name = alias->metric_name;
1431 			j++;
1432 		}
1433 		if (pmu->selectable &&
1434 		    (event_glob == NULL || strglobmatch(pmu->name, event_glob))) {
1435 			char *s;
1436 			if (asprintf(&s, "%s//", pmu->name) < 0)
1437 				goto out_enomem;
1438 			aliases[j].name = s;
1439 			j++;
1440 		}
1441 	}
1442 	len = j;
1443 	qsort(aliases, len, sizeof(struct sevent), cmp_sevent);
1444 	for (j = 0; j < len; j++) {
1445 		/* Skip duplicates */
1446 		if (j > 0 && !strcmp(aliases[j].name, aliases[j - 1].name))
1447 			continue;
1448 		if (name_only) {
1449 			printf("%s ", aliases[j].name);
1450 			continue;
1451 		}
1452 		if (aliases[j].desc && !quiet_flag) {
1453 			if (numdesc++ == 0)
1454 				printf("\n");
1455 			if (aliases[j].topic && (!topic ||
1456 					strcmp(topic, aliases[j].topic))) {
1457 				printf("%s%s:\n", topic ? "\n" : "",
1458 						aliases[j].topic);
1459 				topic = aliases[j].topic;
1460 			}
1461 			printf("  %-50s\n", aliases[j].name);
1462 			printf("%*s", 8, "[");
1463 			wordwrap(aliases[j].desc, 8, columns, 0);
1464 			printf("]\n");
1465 			if (details_flag) {
1466 				printf("%*s%s/%s/ ", 8, "", aliases[j].pmu, aliases[j].str);
1467 				if (aliases[j].metric_name)
1468 					printf(" MetricName: %s", aliases[j].metric_name);
1469 				if (aliases[j].metric_expr)
1470 					printf(" MetricExpr: %s", aliases[j].metric_expr);
1471 				putchar('\n');
1472 			}
1473 		} else
1474 			printf("  %-50s [Kernel PMU event]\n", aliases[j].name);
1475 		printed++;
1476 	}
1477 	if (printed && pager_in_use())
1478 		printf("\n");
1479 out_free:
1480 	for (j = 0; j < len; j++)
1481 		zfree(&aliases[j].name);
1482 	zfree(&aliases);
1483 	return;
1484 
1485 out_enomem:
1486 	printf("FATAL: not enough memory to print PMU events\n");
1487 	if (aliases)
1488 		goto out_free;
1489 }
1490 
1491 bool pmu_have_event(const char *pname, const char *name)
1492 {
1493 	struct perf_pmu *pmu;
1494 	struct perf_pmu_alias *alias;
1495 
1496 	pmu = NULL;
1497 	while ((pmu = perf_pmu__scan(pmu)) != NULL) {
1498 		if (strcmp(pname, pmu->name))
1499 			continue;
1500 		list_for_each_entry(alias, &pmu->aliases, list)
1501 			if (!strcmp(alias->name, name))
1502 				return true;
1503 	}
1504 	return false;
1505 }
1506 
1507 static FILE *perf_pmu__open_file(struct perf_pmu *pmu, const char *name)
1508 {
1509 	struct stat st;
1510 	char path[PATH_MAX];
1511 	const char *sysfs;
1512 
1513 	sysfs = sysfs__mountpoint();
1514 	if (!sysfs)
1515 		return NULL;
1516 
1517 	snprintf(path, PATH_MAX,
1518 		 "%s" EVENT_SOURCE_DEVICE_PATH "%s/%s", sysfs, pmu->name, name);
1519 
1520 	if (stat(path, &st) < 0)
1521 		return NULL;
1522 
1523 	return fopen(path, "r");
1524 }
1525 
1526 int perf_pmu__scan_file(struct perf_pmu *pmu, const char *name, const char *fmt,
1527 			...)
1528 {
1529 	va_list args;
1530 	FILE *file;
1531 	int ret = EOF;
1532 
1533 	va_start(args, fmt);
1534 	file = perf_pmu__open_file(pmu, name);
1535 	if (file) {
1536 		ret = vfscanf(file, fmt, args);
1537 		fclose(file);
1538 	}
1539 	va_end(args);
1540 	return ret;
1541 }
1542