xref: /openbmc/linux/tools/perf/util/pmu.c (revision 50a9667c)
1 
2 #include <linux/list.h>
3 #include <sys/types.h>
4 #include <sys/stat.h>
5 #include <unistd.h>
6 #include <stdio.h>
7 #include <dirent.h>
8 #include "sysfs.h"
9 #include "util.h"
10 #include "pmu.h"
11 #include "parse-events.h"
12 
13 #define EVENT_SOURCE_DEVICE_PATH "/bus/event_source/devices/"
14 
15 int perf_pmu_parse(struct list_head *list, char *name);
16 extern FILE *perf_pmu_in;
17 
18 static LIST_HEAD(pmus);
19 
20 /*
21  * Parse & process all the sysfs attributes located under
22  * the directory specified in 'dir' parameter.
23  */
24 static int pmu_format_parse(char *dir, struct list_head *head)
25 {
26 	struct dirent *evt_ent;
27 	DIR *format_dir;
28 	int ret = 0;
29 
30 	format_dir = opendir(dir);
31 	if (!format_dir)
32 		return -EINVAL;
33 
34 	while (!ret && (evt_ent = readdir(format_dir))) {
35 		char path[PATH_MAX];
36 		char *name = evt_ent->d_name;
37 		FILE *file;
38 
39 		if (!strcmp(name, ".") || !strcmp(name, ".."))
40 			continue;
41 
42 		snprintf(path, PATH_MAX, "%s/%s", dir, name);
43 
44 		ret = -EINVAL;
45 		file = fopen(path, "r");
46 		if (!file)
47 			break;
48 
49 		perf_pmu_in = file;
50 		ret = perf_pmu_parse(head, name);
51 		fclose(file);
52 	}
53 
54 	closedir(format_dir);
55 	return ret;
56 }
57 
58 /*
59  * Reading/parsing the default pmu format definition, which should be
60  * located at:
61  * /sys/bus/event_source/devices/<dev>/format as sysfs group attributes.
62  */
63 static int pmu_format(char *name, struct list_head *format)
64 {
65 	struct stat st;
66 	char path[PATH_MAX];
67 	const char *sysfs;
68 
69 	sysfs = sysfs_find_mountpoint();
70 	if (!sysfs)
71 		return -1;
72 
73 	snprintf(path, PATH_MAX,
74 		 "%s" EVENT_SOURCE_DEVICE_PATH "%s/format", sysfs, name);
75 
76 	if (stat(path, &st) < 0)
77 		return 0;	/* no error if format does not exist */
78 
79 	if (pmu_format_parse(path, format))
80 		return -1;
81 
82 	return 0;
83 }
84 
85 static int perf_pmu__new_alias(struct list_head *list, char *name, FILE *file)
86 {
87 	struct perf_pmu__alias *alias;
88 	char buf[256];
89 	int ret;
90 
91 	ret = fread(buf, 1, sizeof(buf), file);
92 	if (ret == 0)
93 		return -EINVAL;
94 	buf[ret] = 0;
95 
96 	alias = malloc(sizeof(*alias));
97 	if (!alias)
98 		return -ENOMEM;
99 
100 	INIT_LIST_HEAD(&alias->terms);
101 	ret = parse_events_terms(&alias->terms, buf);
102 	if (ret) {
103 		free(alias);
104 		return ret;
105 	}
106 
107 	alias->name = strdup(name);
108 	list_add_tail(&alias->list, list);
109 	return 0;
110 }
111 
112 /*
113  * Process all the sysfs attributes located under the directory
114  * specified in 'dir' parameter.
115  */
116 static int pmu_aliases_parse(char *dir, struct list_head *head)
117 {
118 	struct dirent *evt_ent;
119 	DIR *event_dir;
120 	int ret = 0;
121 
122 	event_dir = opendir(dir);
123 	if (!event_dir)
124 		return -EINVAL;
125 
126 	while (!ret && (evt_ent = readdir(event_dir))) {
127 		char path[PATH_MAX];
128 		char *name = evt_ent->d_name;
129 		FILE *file;
130 
131 		if (!strcmp(name, ".") || !strcmp(name, ".."))
132 			continue;
133 
134 		snprintf(path, PATH_MAX, "%s/%s", dir, name);
135 
136 		ret = -EINVAL;
137 		file = fopen(path, "r");
138 		if (!file)
139 			break;
140 		ret = perf_pmu__new_alias(head, name, file);
141 		fclose(file);
142 	}
143 
144 	closedir(event_dir);
145 	return ret;
146 }
147 
148 /*
149  * Reading the pmu event aliases definition, which should be located at:
150  * /sys/bus/event_source/devices/<dev>/events as sysfs group attributes.
151  */
152 static int pmu_aliases(char *name, struct list_head *head)
153 {
154 	struct stat st;
155 	char path[PATH_MAX];
156 	const char *sysfs;
157 
158 	sysfs = sysfs_find_mountpoint();
159 	if (!sysfs)
160 		return -1;
161 
162 	snprintf(path, PATH_MAX,
163 		 "%s/bus/event_source/devices/%s/events", sysfs, name);
164 
165 	if (stat(path, &st) < 0)
166 		return -1;
167 
168 	if (pmu_aliases_parse(path, head))
169 		return -1;
170 
171 	return 0;
172 }
173 
174 static int pmu_alias_terms(struct perf_pmu__alias *alias,
175 			   struct list_head *terms)
176 {
177 	struct parse_events__term *term, *clone;
178 	LIST_HEAD(list);
179 	int ret;
180 
181 	list_for_each_entry(term, &alias->terms, list) {
182 		ret = parse_events__term_clone(&clone, term);
183 		if (ret) {
184 			parse_events__free_terms(&list);
185 			return ret;
186 		}
187 		list_add_tail(&clone->list, &list);
188 	}
189 	list_splice(&list, terms);
190 	return 0;
191 }
192 
193 /*
194  * Reading/parsing the default pmu type value, which should be
195  * located at:
196  * /sys/bus/event_source/devices/<dev>/type as sysfs attribute.
197  */
198 static int pmu_type(char *name, __u32 *type)
199 {
200 	struct stat st;
201 	char path[PATH_MAX];
202 	const char *sysfs;
203 	FILE *file;
204 	int ret = 0;
205 
206 	sysfs = sysfs_find_mountpoint();
207 	if (!sysfs)
208 		return -1;
209 
210 	snprintf(path, PATH_MAX,
211 		 "%s" EVENT_SOURCE_DEVICE_PATH "%s/type", sysfs, name);
212 
213 	if (stat(path, &st) < 0)
214 		return -1;
215 
216 	file = fopen(path, "r");
217 	if (!file)
218 		return -EINVAL;
219 
220 	if (1 != fscanf(file, "%u", type))
221 		ret = -1;
222 
223 	fclose(file);
224 	return ret;
225 }
226 
227 /* Add all pmus in sysfs to pmu list: */
228 static void pmu_read_sysfs(void)
229 {
230 	char path[PATH_MAX];
231 	const char *sysfs;
232 	DIR *dir;
233 	struct dirent *dent;
234 
235 	sysfs = sysfs_find_mountpoint();
236 	if (!sysfs)
237 		return;
238 
239 	snprintf(path, PATH_MAX,
240 		 "%s" EVENT_SOURCE_DEVICE_PATH, sysfs);
241 
242 	dir = opendir(path);
243 	if (!dir)
244 		return;
245 
246 	while ((dent = readdir(dir))) {
247 		if (!strcmp(dent->d_name, ".") || !strcmp(dent->d_name, ".."))
248 			continue;
249 		/* add to static LIST_HEAD(pmus): */
250 		perf_pmu__find(dent->d_name);
251 	}
252 
253 	closedir(dir);
254 }
255 
256 static struct perf_pmu *pmu_lookup(char *name)
257 {
258 	struct perf_pmu *pmu;
259 	LIST_HEAD(format);
260 	LIST_HEAD(aliases);
261 	__u32 type;
262 
263 	/*
264 	 * The pmu data we store & need consists of the pmu
265 	 * type value and format definitions. Load both right
266 	 * now.
267 	 */
268 	if (pmu_format(name, &format))
269 		return NULL;
270 
271 	if (pmu_type(name, &type))
272 		return NULL;
273 
274 	pmu = zalloc(sizeof(*pmu));
275 	if (!pmu)
276 		return NULL;
277 
278 	pmu_aliases(name, &aliases);
279 
280 	INIT_LIST_HEAD(&pmu->format);
281 	INIT_LIST_HEAD(&pmu->aliases);
282 	list_splice(&format, &pmu->format);
283 	list_splice(&aliases, &pmu->aliases);
284 	pmu->name = strdup(name);
285 	pmu->type = type;
286 	list_add_tail(&pmu->list, &pmus);
287 	return pmu;
288 }
289 
290 static struct perf_pmu *pmu_find(char *name)
291 {
292 	struct perf_pmu *pmu;
293 
294 	list_for_each_entry(pmu, &pmus, list)
295 		if (!strcmp(pmu->name, name))
296 			return pmu;
297 
298 	return NULL;
299 }
300 
301 struct perf_pmu *perf_pmu__scan(struct perf_pmu *pmu)
302 {
303 	/*
304 	 * pmu iterator: If pmu is NULL, we start at the begin,
305 	 * otherwise return the next pmu. Returns NULL on end.
306 	 */
307 	if (!pmu) {
308 		pmu_read_sysfs();
309 		pmu = list_prepare_entry(pmu, &pmus, list);
310 	}
311 	list_for_each_entry_continue(pmu, &pmus, list)
312 		return pmu;
313 	return NULL;
314 }
315 
316 struct perf_pmu *perf_pmu__find(char *name)
317 {
318 	struct perf_pmu *pmu;
319 
320 	/*
321 	 * Once PMU is loaded it stays in the list,
322 	 * so we keep us from multiple reading/parsing
323 	 * the pmu format definitions.
324 	 */
325 	pmu = pmu_find(name);
326 	if (pmu)
327 		return pmu;
328 
329 	return pmu_lookup(name);
330 }
331 
332 static struct perf_pmu__format*
333 pmu_find_format(struct list_head *formats, char *name)
334 {
335 	struct perf_pmu__format *format;
336 
337 	list_for_each_entry(format, formats, list)
338 		if (!strcmp(format->name, name))
339 			return format;
340 
341 	return NULL;
342 }
343 
344 /*
345  * Returns value based on the format definition (format parameter)
346  * and unformated value (value parameter).
347  *
348  * TODO maybe optimize a little ;)
349  */
350 static __u64 pmu_format_value(unsigned long *format, __u64 value)
351 {
352 	unsigned long fbit, vbit;
353 	__u64 v = 0;
354 
355 	for (fbit = 0, vbit = 0; fbit < PERF_PMU_FORMAT_BITS; fbit++) {
356 
357 		if (!test_bit(fbit, format))
358 			continue;
359 
360 		if (!(value & (1llu << vbit++)))
361 			continue;
362 
363 		v |= (1llu << fbit);
364 	}
365 
366 	return v;
367 }
368 
369 /*
370  * Setup one of config[12] attr members based on the
371  * user input data - temr parameter.
372  */
373 static int pmu_config_term(struct list_head *formats,
374 			   struct perf_event_attr *attr,
375 			   struct parse_events__term *term)
376 {
377 	struct perf_pmu__format *format;
378 	__u64 *vp;
379 
380 	/*
381 	 * Support only for hardcoded and numnerial terms.
382 	 * Hardcoded terms should be already in, so nothing
383 	 * to be done for them.
384 	 */
385 	if (parse_events__is_hardcoded_term(term))
386 		return 0;
387 
388 	if (term->type_val != PARSE_EVENTS__TERM_TYPE_NUM)
389 		return -EINVAL;
390 
391 	format = pmu_find_format(formats, term->config);
392 	if (!format)
393 		return -EINVAL;
394 
395 	switch (format->value) {
396 	case PERF_PMU_FORMAT_VALUE_CONFIG:
397 		vp = &attr->config;
398 		break;
399 	case PERF_PMU_FORMAT_VALUE_CONFIG1:
400 		vp = &attr->config1;
401 		break;
402 	case PERF_PMU_FORMAT_VALUE_CONFIG2:
403 		vp = &attr->config2;
404 		break;
405 	default:
406 		return -EINVAL;
407 	}
408 
409 	/*
410 	 * XXX If we ever decide to go with string values for
411 	 * non-hardcoded terms, here's the place to translate
412 	 * them into value.
413 	 */
414 	*vp |= pmu_format_value(format->bits, term->val.num);
415 	return 0;
416 }
417 
418 static int pmu_config(struct list_head *formats, struct perf_event_attr *attr,
419 		      struct list_head *head_terms)
420 {
421 	struct parse_events__term *term;
422 
423 	list_for_each_entry(term, head_terms, list)
424 		if (pmu_config_term(formats, attr, term))
425 			return -EINVAL;
426 
427 	return 0;
428 }
429 
430 /*
431  * Configures event's 'attr' parameter based on the:
432  * 1) users input - specified in terms parameter
433  * 2) pmu format definitions - specified by pmu parameter
434  */
435 int perf_pmu__config(struct perf_pmu *pmu, struct perf_event_attr *attr,
436 		     struct list_head *head_terms)
437 {
438 	attr->type = pmu->type;
439 	return pmu_config(&pmu->format, attr, head_terms);
440 }
441 
442 static struct perf_pmu__alias *pmu_find_alias(struct perf_pmu *pmu,
443 					      struct parse_events__term *term)
444 {
445 	struct perf_pmu__alias *alias;
446 	char *name;
447 
448 	if (parse_events__is_hardcoded_term(term))
449 		return NULL;
450 
451 	if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM) {
452 		if (term->val.num != 1)
453 			return NULL;
454 		if (pmu_find_format(&pmu->format, term->config))
455 			return NULL;
456 		name = term->config;
457 	} else if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR) {
458 		if (strcasecmp(term->config, "event"))
459 			return NULL;
460 		name = term->val.str;
461 	} else {
462 		return NULL;
463 	}
464 
465 	list_for_each_entry(alias, &pmu->aliases, list) {
466 		if (!strcasecmp(alias->name, name))
467 			return alias;
468 	}
469 	return NULL;
470 }
471 
472 /*
473  * Find alias in the terms list and replace it with the terms
474  * defined for the alias
475  */
476 int perf_pmu__check_alias(struct perf_pmu *pmu, struct list_head *head_terms)
477 {
478 	struct parse_events__term *term, *h;
479 	struct perf_pmu__alias *alias;
480 	int ret;
481 
482 	list_for_each_entry_safe(term, h, head_terms, list) {
483 		alias = pmu_find_alias(pmu, term);
484 		if (!alias)
485 			continue;
486 		ret = pmu_alias_terms(alias, &term->list);
487 		if (ret)
488 			return ret;
489 		list_del(&term->list);
490 		free(term);
491 	}
492 	return 0;
493 }
494 
495 int perf_pmu__new_format(struct list_head *list, char *name,
496 			 int config, unsigned long *bits)
497 {
498 	struct perf_pmu__format *format;
499 
500 	format = zalloc(sizeof(*format));
501 	if (!format)
502 		return -ENOMEM;
503 
504 	format->name = strdup(name);
505 	format->value = config;
506 	memcpy(format->bits, bits, sizeof(format->bits));
507 
508 	list_add_tail(&format->list, list);
509 	return 0;
510 }
511 
512 void perf_pmu__set_format(unsigned long *bits, long from, long to)
513 {
514 	long b;
515 
516 	if (!to)
517 		to = from;
518 
519 	memset(bits, 0, BITS_TO_LONGS(PERF_PMU_FORMAT_BITS));
520 	for (b = from; b <= to; b++)
521 		set_bit(b, bits);
522 }
523 
524 /* Simulated format definitions. */
525 static struct test_format {
526 	const char *name;
527 	const char *value;
528 } test_formats[] = {
529 	{ "krava01", "config:0-1,62-63\n", },
530 	{ "krava02", "config:10-17\n", },
531 	{ "krava03", "config:5\n", },
532 	{ "krava11", "config1:0,2,4,6,8,20-28\n", },
533 	{ "krava12", "config1:63\n", },
534 	{ "krava13", "config1:45-47\n", },
535 	{ "krava21", "config2:0-3,10-13,20-23,30-33,40-43,50-53,60-63\n", },
536 	{ "krava22", "config2:8,18,48,58\n", },
537 	{ "krava23", "config2:28-29,38\n", },
538 };
539 
540 #define TEST_FORMATS_CNT (sizeof(test_formats) / sizeof(struct test_format))
541 
542 /* Simulated users input. */
543 static struct parse_events__term test_terms[] = {
544 	{
545 		.config    = (char *) "krava01",
546 		.val.num   = 15,
547 		.type_val  = PARSE_EVENTS__TERM_TYPE_NUM,
548 		.type_term = PARSE_EVENTS__TERM_TYPE_USER,
549 	},
550 	{
551 		.config    = (char *) "krava02",
552 		.val.num   = 170,
553 		.type_val  = PARSE_EVENTS__TERM_TYPE_NUM,
554 		.type_term = PARSE_EVENTS__TERM_TYPE_USER,
555 	},
556 	{
557 		.config    = (char *) "krava03",
558 		.val.num   = 1,
559 		.type_val  = PARSE_EVENTS__TERM_TYPE_NUM,
560 		.type_term = PARSE_EVENTS__TERM_TYPE_USER,
561 	},
562 	{
563 		.config    = (char *) "krava11",
564 		.val.num   = 27,
565 		.type_val  = PARSE_EVENTS__TERM_TYPE_NUM,
566 		.type_term = PARSE_EVENTS__TERM_TYPE_USER,
567 	},
568 	{
569 		.config    = (char *) "krava12",
570 		.val.num   = 1,
571 		.type_val  = PARSE_EVENTS__TERM_TYPE_NUM,
572 		.type_term = PARSE_EVENTS__TERM_TYPE_USER,
573 	},
574 	{
575 		.config    = (char *) "krava13",
576 		.val.num   = 2,
577 		.type_val  = PARSE_EVENTS__TERM_TYPE_NUM,
578 		.type_term = PARSE_EVENTS__TERM_TYPE_USER,
579 	},
580 	{
581 		.config    = (char *) "krava21",
582 		.val.num   = 119,
583 		.type_val  = PARSE_EVENTS__TERM_TYPE_NUM,
584 		.type_term = PARSE_EVENTS__TERM_TYPE_USER,
585 	},
586 	{
587 		.config    = (char *) "krava22",
588 		.val.num   = 11,
589 		.type_val  = PARSE_EVENTS__TERM_TYPE_NUM,
590 		.type_term = PARSE_EVENTS__TERM_TYPE_USER,
591 	},
592 	{
593 		.config    = (char *) "krava23",
594 		.val.num   = 2,
595 		.type_val  = PARSE_EVENTS__TERM_TYPE_NUM,
596 		.type_term = PARSE_EVENTS__TERM_TYPE_USER,
597 	},
598 };
599 #define TERMS_CNT (sizeof(test_terms) / sizeof(struct parse_events__term))
600 
601 /*
602  * Prepare format directory data, exported by kernel
603  * at /sys/bus/event_source/devices/<dev>/format.
604  */
605 static char *test_format_dir_get(void)
606 {
607 	static char dir[PATH_MAX];
608 	unsigned int i;
609 
610 	snprintf(dir, PATH_MAX, "/tmp/perf-pmu-test-format-XXXXXX");
611 	if (!mkdtemp(dir))
612 		return NULL;
613 
614 	for (i = 0; i < TEST_FORMATS_CNT; i++) {
615 		static char name[PATH_MAX];
616 		struct test_format *format = &test_formats[i];
617 		FILE *file;
618 
619 		snprintf(name, PATH_MAX, "%s/%s", dir, format->name);
620 
621 		file = fopen(name, "w");
622 		if (!file)
623 			return NULL;
624 
625 		if (1 != fwrite(format->value, strlen(format->value), 1, file))
626 			break;
627 
628 		fclose(file);
629 	}
630 
631 	return dir;
632 }
633 
634 /* Cleanup format directory. */
635 static int test_format_dir_put(char *dir)
636 {
637 	char buf[PATH_MAX];
638 	snprintf(buf, PATH_MAX, "rm -f %s/*\n", dir);
639 	if (system(buf))
640 		return -1;
641 
642 	snprintf(buf, PATH_MAX, "rmdir %s\n", dir);
643 	return system(buf);
644 }
645 
646 static struct list_head *test_terms_list(void)
647 {
648 	static LIST_HEAD(terms);
649 	unsigned int i;
650 
651 	for (i = 0; i < TERMS_CNT; i++)
652 		list_add_tail(&test_terms[i].list, &terms);
653 
654 	return &terms;
655 }
656 
657 #undef TERMS_CNT
658 
659 int perf_pmu__test(void)
660 {
661 	char *format = test_format_dir_get();
662 	LIST_HEAD(formats);
663 	struct list_head *terms = test_terms_list();
664 	int ret;
665 
666 	if (!format)
667 		return -EINVAL;
668 
669 	do {
670 		struct perf_event_attr attr;
671 
672 		memset(&attr, 0, sizeof(attr));
673 
674 		ret = pmu_format_parse(format, &formats);
675 		if (ret)
676 			break;
677 
678 		ret = pmu_config(&formats, &attr, terms);
679 		if (ret)
680 			break;
681 
682 		ret = -EINVAL;
683 
684 		if (attr.config  != 0xc00000000002a823)
685 			break;
686 		if (attr.config1 != 0x8000400000000145)
687 			break;
688 		if (attr.config2 != 0x0400000020041d07)
689 			break;
690 
691 		ret = 0;
692 	} while (0);
693 
694 	test_format_dir_put(format);
695 	return ret;
696 }
697