xref: /linux/tools/perf/util/hwmon_pmu.c (revision 8faabc041a001140564f718dabe37753e88b37fa)
1 // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
2 #include "counts.h"
3 #include "debug.h"
4 #include "evsel.h"
5 #include "hashmap.h"
6 #include "hwmon_pmu.h"
7 #include "pmu.h"
8 #include <internal/xyarray.h>
9 #include <internal/threadmap.h>
10 #include <perf/threadmap.h>
11 #include <sys/types.h>
12 #include <assert.h>
13 #include <ctype.h>
14 #include <dirent.h>
15 #include <fcntl.h>
16 #include <stddef.h>
17 #include <stdlib.h>
18 #include <string.h>
19 #include <api/fs/fs.h>
20 #include <api/io.h>
21 #include <linux/kernel.h>
22 #include <linux/string.h>
23 #include <linux/zalloc.h>
24 
25 /** Strings that correspond to enum hwmon_type. */
26 static const char * const hwmon_type_strs[HWMON_TYPE_MAX] = {
27 	NULL,
28 	"cpu",
29 	"curr",
30 	"energy",
31 	"fan",
32 	"humidity",
33 	"in",
34 	"intrusion",
35 	"power",
36 	"pwm",
37 	"temp",
38 };
39 #define LONGEST_HWMON_TYPE_STR "intrusion"
40 
41 /** Strings that correspond to enum hwmon_item. */
42 static const char * const hwmon_item_strs[HWMON_ITEM__MAX] = {
43 	NULL,
44 	"accuracy",
45 	"alarm",
46 	"auto_channels_temp",
47 	"average",
48 	"average_highest",
49 	"average_interval",
50 	"average_interval_max",
51 	"average_interval_min",
52 	"average_lowest",
53 	"average_max",
54 	"average_min",
55 	"beep",
56 	"cap",
57 	"cap_hyst",
58 	"cap_max",
59 	"cap_min",
60 	"crit",
61 	"crit_hyst",
62 	"div",
63 	"emergency",
64 	"emergency_hist",
65 	"enable",
66 	"fault",
67 	"freq",
68 	"highest",
69 	"input",
70 	"label",
71 	"lcrit",
72 	"lcrit_hyst",
73 	"lowest",
74 	"max",
75 	"max_hyst",
76 	"min",
77 	"min_hyst",
78 	"mod",
79 	"offset",
80 	"pulses",
81 	"rated_max",
82 	"rated_min",
83 	"reset_history",
84 	"target",
85 	"type",
86 	"vid",
87 };
88 #define LONGEST_HWMON_ITEM_STR "average_interval_max"
89 
90 static const char *const hwmon_units[HWMON_TYPE_MAX] = {
91 	NULL,
92 	"V",   /* cpu */
93 	"A",   /* curr */
94 	"J",   /* energy */
95 	"rpm", /* fan */
96 	"%",   /* humidity */
97 	"V",   /* in */
98 	"",    /* intrusion */
99 	"W",   /* power */
100 	"Hz",  /* pwm */
101 	"'C",  /* temp */
102 };
103 
104 struct hwmon_pmu {
105 	struct perf_pmu pmu;
106 	struct hashmap events;
107 	int hwmon_dir_fd;
108 };
109 
110 /**
111  * union hwmon_pmu_event_key: Key for hwmon_pmu->events as such each key
112  * represents an event.
113  *
114  * Related hwmon files start <type><number> that this key represents.
115  */
116 union hwmon_pmu_event_key {
117 	long type_and_num;
118 	struct {
119 		int num :16;
120 		enum hwmon_type type :8;
121 	};
122 };
123 
124 /**
125  * struct hwmon_pmu_event_value: Value in hwmon_pmu->events.
126  *
127  * Hwmon files are of the form <type><number>_<item> and may have a suffix
128  * _alarm.
129  */
130 struct hwmon_pmu_event_value {
131 	/** @items: which item files are present. */
132 	DECLARE_BITMAP(items, HWMON_ITEM__MAX);
133 	/** @alarm_items: which item files are present. */
134 	DECLARE_BITMAP(alarm_items, HWMON_ITEM__MAX);
135 	/** @label: contents of <type><number>_label if present. */
136 	char *label;
137 	/** @name: name computed from label of the form <type>_<label>. */
138 	char *name;
139 };
140 
141 bool perf_pmu__is_hwmon(const struct perf_pmu *pmu)
142 {
143 	return pmu && pmu->type >= PERF_PMU_TYPE_HWMON_START &&
144 		pmu->type <= PERF_PMU_TYPE_HWMON_END;
145 }
146 
147 bool evsel__is_hwmon(const struct evsel *evsel)
148 {
149 	return perf_pmu__is_hwmon(evsel->pmu);
150 }
151 
152 static size_t hwmon_pmu__event_hashmap_hash(long key, void *ctx __maybe_unused)
153 {
154 	return ((union hwmon_pmu_event_key)key).type_and_num;
155 }
156 
157 static bool hwmon_pmu__event_hashmap_equal(long key1, long key2, void *ctx __maybe_unused)
158 {
159 	return ((union hwmon_pmu_event_key)key1).type_and_num ==
160 	       ((union hwmon_pmu_event_key)key2).type_and_num;
161 }
162 
163 static int hwmon_strcmp(const void *a, const void *b)
164 {
165 	const char *sa = a;
166 	const char * const *sb = b;
167 
168 	return strcmp(sa, *sb);
169 }
170 
171 bool parse_hwmon_filename(const char *filename,
172 			  enum hwmon_type *type,
173 			  int *number,
174 			  enum hwmon_item *item,
175 			  bool *alarm)
176 {
177 	char fn_type[24];
178 	const char **elem;
179 	const char *fn_item = NULL;
180 	size_t fn_item_len;
181 
182 	assert(strlen(LONGEST_HWMON_TYPE_STR) < sizeof(fn_type));
183 	strlcpy(fn_type, filename, sizeof(fn_type));
184 	for (size_t i = 0; fn_type[i] != '\0'; i++) {
185 		if (fn_type[i] >= '0' && fn_type[i] <= '9') {
186 			fn_type[i] = '\0';
187 			*number = strtoul(&filename[i], (char **)&fn_item, 10);
188 			if (*fn_item == '_')
189 				fn_item++;
190 			break;
191 		}
192 		if (fn_type[i] == '_') {
193 			fn_type[i] = '\0';
194 			*number = -1;
195 			fn_item = &filename[i + 1];
196 			break;
197 		}
198 	}
199 	if (fn_item == NULL || fn_type[0] == '\0' || (item != NULL && fn_item[0] == '\0')) {
200 		pr_debug3("hwmon_pmu: not a hwmon file '%s'\n", filename);
201 		return false;
202 	}
203 	elem = bsearch(&fn_type, hwmon_type_strs + 1, ARRAY_SIZE(hwmon_type_strs) - 1,
204 		       sizeof(hwmon_type_strs[0]), hwmon_strcmp);
205 	if (!elem) {
206 		pr_debug3("hwmon_pmu: not a hwmon type '%s' in file name '%s'\n",
207 			 fn_type, filename);
208 		return false;
209 	}
210 
211 	*type = elem - &hwmon_type_strs[0];
212 	if (!item)
213 		return true;
214 
215 	*alarm = false;
216 	fn_item_len = strlen(fn_item);
217 	if (fn_item_len > 6 && !strcmp(&fn_item[fn_item_len - 6], "_alarm")) {
218 		assert(strlen(LONGEST_HWMON_ITEM_STR) < sizeof(fn_type));
219 		strlcpy(fn_type, fn_item, fn_item_len - 5);
220 		fn_item = fn_type;
221 		*alarm = true;
222 	}
223 	elem = bsearch(fn_item, hwmon_item_strs + 1, ARRAY_SIZE(hwmon_item_strs) - 1,
224 		       sizeof(hwmon_item_strs[0]), hwmon_strcmp);
225 	if (!elem) {
226 		pr_debug3("hwmon_pmu: not a hwmon item '%s' in file name '%s'\n",
227 			 fn_item, filename);
228 		return false;
229 	}
230 	*item = elem - &hwmon_item_strs[0];
231 	return true;
232 }
233 
234 static void fix_name(char *p)
235 {
236 	char *s = strchr(p, '\n');
237 
238 	if (s)
239 		*s = '\0';
240 
241 	while (*p != '\0') {
242 		if (strchr(" :,/\n\t", *p))
243 			*p = '_';
244 		else
245 			*p = tolower(*p);
246 		p++;
247 	}
248 }
249 
250 static int hwmon_pmu__read_events(struct hwmon_pmu *pmu)
251 {
252 	DIR *dir;
253 	struct dirent *ent;
254 	int dup_fd, err = 0;
255 	struct hashmap_entry *cur, *tmp;
256 	size_t bkt;
257 
258 	if (pmu->pmu.sysfs_aliases_loaded)
259 		return 0;
260 
261 	/*
262 	 * Use a dup-ed fd as closedir will close it. Use openat so that the
263 	 * directory contents are refreshed.
264 	 */
265 	dup_fd = openat(pmu->hwmon_dir_fd, ".", O_DIRECTORY);
266 
267 	if (dup_fd == -1)
268 		return -ENOMEM;
269 
270 	dir = fdopendir(dup_fd);
271 	if (!dir) {
272 		close(dup_fd);
273 		return -ENOMEM;
274 	}
275 
276 	while ((ent = readdir(dir)) != NULL) {
277 		enum hwmon_type type;
278 		int number;
279 		enum hwmon_item item;
280 		bool alarm;
281 		union hwmon_pmu_event_key key = { .type_and_num = 0 };
282 		struct hwmon_pmu_event_value *value;
283 
284 		if (ent->d_type != DT_REG)
285 			continue;
286 
287 		if (!parse_hwmon_filename(ent->d_name, &type, &number, &item, &alarm)) {
288 			pr_debug3("Not a hwmon file '%s'\n", ent->d_name);
289 			continue;
290 		}
291 		key.num = number;
292 		key.type = type;
293 		if (!hashmap__find(&pmu->events, key.type_and_num, &value)) {
294 			value = zalloc(sizeof(*value));
295 			if (!value) {
296 				err = -ENOMEM;
297 				goto err_out;
298 			}
299 			err = hashmap__add(&pmu->events, key.type_and_num, value);
300 			if (err) {
301 				free(value);
302 				err = -ENOMEM;
303 				goto err_out;
304 			}
305 		}
306 		__set_bit(item, alarm ? value->alarm_items : value->items);
307 		if (item == HWMON_ITEM_LABEL) {
308 			char buf[128];
309 			int fd = openat(pmu->hwmon_dir_fd, ent->d_name, O_RDONLY);
310 			ssize_t read_len;
311 
312 			if (fd < 0)
313 				continue;
314 
315 			read_len = read(fd, buf, sizeof(buf));
316 
317 			while (read_len > 0 && buf[read_len - 1] == '\n')
318 				read_len--;
319 
320 			if (read_len > 0)
321 				buf[read_len] = '\0';
322 
323 			if (buf[0] == '\0') {
324 				pr_debug("hwmon_pmu: empty label file %s %s\n",
325 					 pmu->pmu.name, ent->d_name);
326 				close(fd);
327 				continue;
328 			}
329 			value->label = strdup(buf);
330 			if (!value->label) {
331 				pr_debug("hwmon_pmu: memory allocation failure\n");
332 				close(fd);
333 				continue;
334 			}
335 			snprintf(buf, sizeof(buf), "%s_%s", hwmon_type_strs[type], value->label);
336 			fix_name(buf);
337 			value->name = strdup(buf);
338 			if (!value->name)
339 				pr_debug("hwmon_pmu: memory allocation failure\n");
340 			close(fd);
341 		}
342 	}
343 	if (hashmap__size(&pmu->events) == 0)
344 		pr_debug2("hwmon_pmu: %s has no events\n", pmu->pmu.name);
345 
346 	hashmap__for_each_entry_safe((&pmu->events), cur, tmp, bkt) {
347 		union hwmon_pmu_event_key key = {
348 			.type_and_num = cur->key,
349 		};
350 		struct hwmon_pmu_event_value *value = cur->pvalue;
351 
352 		if (!test_bit(HWMON_ITEM_INPUT, value->items)) {
353 			pr_debug("hwmon_pmu: %s removing event '%s%d' that has no input file\n",
354 				pmu->pmu.name, hwmon_type_strs[key.type], key.num);
355 			hashmap__delete(&pmu->events, key.type_and_num, &key, &value);
356 			zfree(&value->label);
357 			zfree(&value->name);
358 			free(value);
359 		}
360 	}
361 	pmu->pmu.sysfs_aliases_loaded = true;
362 
363 err_out:
364 	closedir(dir);
365 	return err;
366 }
367 
368 struct perf_pmu *hwmon_pmu__new(struct list_head *pmus, int hwmon_dir, const char *sysfs_name, const char *name)
369 {
370 	char buf[32];
371 	struct hwmon_pmu *hwm;
372 
373 	hwm = zalloc(sizeof(*hwm));
374 	if (!hwm)
375 		return NULL;
376 
377 	hwm->hwmon_dir_fd = hwmon_dir;
378 	hwm->pmu.type = PERF_PMU_TYPE_HWMON_START + strtoul(sysfs_name + 5, NULL, 10);
379 	if (hwm->pmu.type > PERF_PMU_TYPE_HWMON_END) {
380 		pr_err("Unable to encode hwmon type from %s in valid PMU type\n", sysfs_name);
381 		goto err_out;
382 	}
383 	snprintf(buf, sizeof(buf), "hwmon_%s", name);
384 	fix_name(buf + 6);
385 	hwm->pmu.name = strdup(buf);
386 	if (!hwm->pmu.name)
387 		goto err_out;
388 	hwm->pmu.alias_name = strdup(sysfs_name);
389 	if (!hwm->pmu.alias_name)
390 		goto err_out;
391 	hwm->pmu.cpus = perf_cpu_map__new("0");
392 	if (!hwm->pmu.cpus)
393 		goto err_out;
394 	INIT_LIST_HEAD(&hwm->pmu.format);
395 	INIT_LIST_HEAD(&hwm->pmu.aliases);
396 	INIT_LIST_HEAD(&hwm->pmu.caps);
397 	hashmap__init(&hwm->events, hwmon_pmu__event_hashmap_hash,
398 		      hwmon_pmu__event_hashmap_equal, /*ctx=*/NULL);
399 
400 	list_add_tail(&hwm->pmu.list, pmus);
401 	return &hwm->pmu;
402 err_out:
403 	free((char *)hwm->pmu.name);
404 	free(hwm->pmu.alias_name);
405 	free(hwm);
406 	close(hwmon_dir);
407 	return NULL;
408 }
409 
410 void hwmon_pmu__exit(struct perf_pmu *pmu)
411 {
412 	struct hwmon_pmu *hwm = container_of(pmu, struct hwmon_pmu, pmu);
413 	struct hashmap_entry *cur, *tmp;
414 	size_t bkt;
415 
416 	hashmap__for_each_entry_safe((&hwm->events), cur, tmp, bkt) {
417 		struct hwmon_pmu_event_value *value = cur->pvalue;
418 
419 		zfree(&value->label);
420 		zfree(&value->name);
421 		free(value);
422 	}
423 	hashmap__clear(&hwm->events);
424 	close(hwm->hwmon_dir_fd);
425 }
426 
427 static size_t hwmon_pmu__describe_items(struct hwmon_pmu *hwm, char *out_buf, size_t out_buf_len,
428 					union hwmon_pmu_event_key key,
429 					const unsigned long *items, bool is_alarm)
430 {
431 	size_t bit;
432 	char buf[64];
433 	size_t len = 0;
434 
435 	for_each_set_bit(bit, items, HWMON_ITEM__MAX) {
436 		int fd;
437 
438 		if (bit == HWMON_ITEM_LABEL || bit == HWMON_ITEM_INPUT)
439 			continue;
440 
441 		snprintf(buf, sizeof(buf), "%s%d_%s%s",
442 			hwmon_type_strs[key.type],
443 			key.num,
444 			hwmon_item_strs[bit],
445 			is_alarm ? "_alarm" : "");
446 		fd = openat(hwm->hwmon_dir_fd, buf, O_RDONLY);
447 		if (fd > 0) {
448 			ssize_t read_len = read(fd, buf, sizeof(buf));
449 
450 			while (read_len > 0 && buf[read_len - 1] == '\n')
451 				read_len--;
452 
453 			if (read_len > 0) {
454 				long long val;
455 
456 				buf[read_len] = '\0';
457 				val = strtoll(buf, /*endptr=*/NULL, 10);
458 				len += snprintf(out_buf + len, out_buf_len - len, "%s%s%s=%g%s",
459 						len == 0 ? " " : ", ",
460 						hwmon_item_strs[bit],
461 						is_alarm ? "_alarm" : "",
462 						(double)val / 1000.0,
463 						hwmon_units[key.type]);
464 			}
465 			close(fd);
466 		}
467 	}
468 	return len;
469 }
470 
471 int hwmon_pmu__for_each_event(struct perf_pmu *pmu, void *state, pmu_event_callback cb)
472 {
473 	struct hwmon_pmu *hwm = container_of(pmu, struct hwmon_pmu, pmu);
474 	struct hashmap_entry *cur;
475 	size_t bkt;
476 
477 	if (hwmon_pmu__read_events(hwm))
478 		return false;
479 
480 	hashmap__for_each_entry((&hwm->events), cur, bkt) {
481 		static const char *const hwmon_scale_units[HWMON_TYPE_MAX] = {
482 			NULL,
483 			"0.001V", /* cpu */
484 			"0.001A", /* curr */
485 			"0.001J", /* energy */
486 			"1rpm",   /* fan */
487 			"0.001%", /* humidity */
488 			"0.001V", /* in */
489 			NULL,     /* intrusion */
490 			"0.001W", /* power */
491 			"1Hz",    /* pwm */
492 			"0.001'C", /* temp */
493 		};
494 		static const char *const hwmon_desc[HWMON_TYPE_MAX] = {
495 			NULL,
496 			"CPU core reference voltage",   /* cpu */
497 			"Current",                      /* curr */
498 			"Cumulative energy use",        /* energy */
499 			"Fan",                          /* fan */
500 			"Humidity",                     /* humidity */
501 			"Voltage",                      /* in */
502 			"Chassis intrusion detection",  /* intrusion */
503 			"Power use",                    /* power */
504 			"Pulse width modulation fan control", /* pwm */
505 			"Temperature",                  /* temp */
506 		};
507 		char alias_buf[64];
508 		char desc_buf[256];
509 		char encoding_buf[128];
510 		union hwmon_pmu_event_key key = {
511 			.type_and_num = cur->key,
512 		};
513 		struct hwmon_pmu_event_value *value = cur->pvalue;
514 		struct pmu_event_info info = {
515 			.pmu = pmu,
516 			.name = value->name,
517 			.alias = alias_buf,
518 			.scale_unit = hwmon_scale_units[key.type],
519 			.desc = desc_buf,
520 			.long_desc = NULL,
521 			.encoding_desc = encoding_buf,
522 			.topic = "hwmon",
523 			.pmu_name = pmu->name,
524 			.event_type_desc = "Hwmon event",
525 		};
526 		int ret;
527 		size_t len;
528 
529 		len = snprintf(alias_buf, sizeof(alias_buf), "%s%d",
530 			       hwmon_type_strs[key.type], key.num);
531 		if (!info.name) {
532 			info.name = info.alias;
533 			info.alias = NULL;
534 		}
535 
536 		len = snprintf(desc_buf, sizeof(desc_buf), "%s in unit %s named %s.",
537 			hwmon_desc[key.type],
538 			pmu->name + 6,
539 			value->label ?: info.name);
540 
541 		len += hwmon_pmu__describe_items(hwm, desc_buf + len, sizeof(desc_buf) - len,
542 						key, value->items, /*is_alarm=*/false);
543 
544 		len += hwmon_pmu__describe_items(hwm, desc_buf + len, sizeof(desc_buf) - len,
545 						key, value->alarm_items, /*is_alarm=*/true);
546 
547 		snprintf(encoding_buf, sizeof(encoding_buf), "%s/config=0x%lx/",
548 			 pmu->name, cur->key);
549 
550 		ret = cb(state, &info);
551 		if (ret)
552 			return ret;
553 	}
554 	return 0;
555 }
556 
557 size_t hwmon_pmu__num_events(struct perf_pmu *pmu)
558 {
559 	struct hwmon_pmu *hwm = container_of(pmu, struct hwmon_pmu, pmu);
560 
561 	hwmon_pmu__read_events(hwm);
562 	return hashmap__size(&hwm->events);
563 }
564 
565 bool hwmon_pmu__have_event(struct perf_pmu *pmu, const char *name)
566 {
567 	struct hwmon_pmu *hwm = container_of(pmu, struct hwmon_pmu, pmu);
568 	enum hwmon_type type;
569 	int number;
570 	union hwmon_pmu_event_key key = { .type_and_num = 0 };
571 	struct hashmap_entry *cur;
572 	size_t bkt;
573 
574 	if (!parse_hwmon_filename(name, &type, &number, /*item=*/NULL, /*is_alarm=*/NULL))
575 		return false;
576 
577 	if (hwmon_pmu__read_events(hwm))
578 		return false;
579 
580 	key.type = type;
581 	key.num = number;
582 	if (hashmap_find(&hwm->events, key.type_and_num, /*value=*/NULL))
583 		return true;
584 	if (key.num != -1)
585 		return false;
586 	/* Item is of form <type>_ which means we should match <type>_<label>. */
587 	hashmap__for_each_entry((&hwm->events), cur, bkt) {
588 		struct hwmon_pmu_event_value *value = cur->pvalue;
589 
590 		key.type_and_num = cur->key;
591 		if (key.type == type && value->name && !strcasecmp(name, value->name))
592 			return true;
593 	}
594 	return false;
595 }
596 
597 static int hwmon_pmu__config_term(const struct hwmon_pmu *hwm,
598 				  struct perf_event_attr *attr,
599 				  struct parse_events_term *term,
600 				  struct parse_events_error *err)
601 {
602 	if (term->type_term == PARSE_EVENTS__TERM_TYPE_USER) {
603 		enum hwmon_type type;
604 		int number;
605 
606 		if (parse_hwmon_filename(term->config, &type, &number,
607 					 /*item=*/NULL, /*is_alarm=*/NULL)) {
608 			if (number == -1) {
609 				/*
610 				 * Item is of form <type>_ which means we should
611 				 * match <type>_<label>.
612 				 */
613 				struct hashmap_entry *cur;
614 				size_t bkt;
615 
616 				attr->config = 0;
617 				hashmap__for_each_entry((&hwm->events), cur, bkt) {
618 					union hwmon_pmu_event_key key = {
619 						.type_and_num = cur->key,
620 					};
621 					struct hwmon_pmu_event_value *value = cur->pvalue;
622 
623 					if (key.type == type && value->name &&
624 					    !strcasecmp(term->config, value->name)) {
625 						attr->config = key.type_and_num;
626 						break;
627 					}
628 				}
629 				if (attr->config == 0)
630 					return -EINVAL;
631 			} else {
632 				union hwmon_pmu_event_key key = {
633 					.type_and_num = 0,
634 				};
635 
636 				key.type = type;
637 				key.num = number;
638 				attr->config = key.type_and_num;
639 			}
640 			return 0;
641 		}
642 	}
643 	if (err) {
644 		char *err_str;
645 
646 		parse_events_error__handle(err, term->err_val,
647 					asprintf(&err_str,
648 						"unexpected hwmon event term (%s) %s",
649 						parse_events__term_type_str(term->type_term),
650 						term->config) < 0
651 					? strdup("unexpected hwmon event term")
652 					: err_str,
653 					NULL);
654 	}
655 	return -EINVAL;
656 }
657 
658 int hwmon_pmu__config_terms(const struct perf_pmu *pmu,
659 			    struct perf_event_attr *attr,
660 			    struct parse_events_terms *terms,
661 			    struct parse_events_error *err)
662 {
663 	struct hwmon_pmu *hwm = container_of(pmu, struct hwmon_pmu, pmu);
664 	struct parse_events_term *term;
665 	int ret;
666 
667 	ret = hwmon_pmu__read_events(hwm);
668 	if (ret)
669 		return ret;
670 
671 	list_for_each_entry(term, &terms->terms, list) {
672 		if (hwmon_pmu__config_term(hwm, attr, term, err))
673 			return -EINVAL;
674 	}
675 
676 	return 0;
677 
678 }
679 
680 int hwmon_pmu__check_alias(struct parse_events_terms *terms, struct perf_pmu_info *info,
681 			   struct parse_events_error *err)
682 {
683 	struct parse_events_term *term =
684 		list_first_entry(&terms->terms, struct parse_events_term, list);
685 
686 	if (term->type_term == PARSE_EVENTS__TERM_TYPE_USER) {
687 		enum hwmon_type type;
688 		int number;
689 
690 		if (parse_hwmon_filename(term->config, &type, &number,
691 					 /*item=*/NULL, /*is_alarm=*/NULL)) {
692 			info->unit = hwmon_units[type];
693 			if (type == HWMON_TYPE_FAN || type == HWMON_TYPE_PWM ||
694 			    type == HWMON_TYPE_INTRUSION)
695 				info->scale = 1;
696 			else
697 				info->scale = 0.001;
698 		}
699 		return 0;
700 	}
701 	if (err) {
702 		char *err_str;
703 
704 		parse_events_error__handle(err, term->err_val,
705 					asprintf(&err_str,
706 						"unexpected hwmon event term (%s) %s",
707 						parse_events__term_type_str(term->type_term),
708 						term->config) < 0
709 					? strdup("unexpected hwmon event term")
710 					: err_str,
711 					NULL);
712 	}
713 	return -EINVAL;
714 }
715 
716 int perf_pmus__read_hwmon_pmus(struct list_head *pmus)
717 {
718 	char *line = NULL;
719 	DIR *class_hwmon_dir;
720 	struct dirent *class_hwmon_ent;
721 	char buf[PATH_MAX];
722 	const char *sysfs = sysfs__mountpoint();
723 
724 	if (!sysfs)
725 		return 0;
726 
727 	scnprintf(buf, sizeof(buf), "%s/class/hwmon/", sysfs);
728 	class_hwmon_dir = opendir(buf);
729 	if (!class_hwmon_dir)
730 		return 0;
731 
732 	while ((class_hwmon_ent = readdir(class_hwmon_dir)) != NULL) {
733 		size_t line_len;
734 		int hwmon_dir, name_fd;
735 		struct io io;
736 
737 		if (class_hwmon_ent->d_type != DT_LNK)
738 			continue;
739 
740 		scnprintf(buf, sizeof(buf), "%s/class/hwmon/%s", sysfs, class_hwmon_ent->d_name);
741 		hwmon_dir = open(buf, O_DIRECTORY);
742 		if (hwmon_dir == -1) {
743 			pr_debug("hwmon_pmu: not a directory: '%s/class/hwmon/%s'\n",
744 				 sysfs, class_hwmon_ent->d_name);
745 			continue;
746 		}
747 		name_fd = openat(hwmon_dir, "name", O_RDONLY);
748 		if (name_fd == -1) {
749 			pr_debug("hwmon_pmu: failure to open '%s/class/hwmon/%s/name'\n",
750 				  sysfs, class_hwmon_ent->d_name);
751 			close(hwmon_dir);
752 			continue;
753 		}
754 		io__init(&io, name_fd, buf, sizeof(buf));
755 		io__getline(&io, &line, &line_len);
756 		if (line_len > 0 && line[line_len - 1] == '\n')
757 			line[line_len - 1] = '\0';
758 		hwmon_pmu__new(pmus, hwmon_dir, class_hwmon_ent->d_name, line);
759 		close(name_fd);
760 	}
761 	free(line);
762 	closedir(class_hwmon_dir);
763 	return 0;
764 }
765 
766 #define FD(e, x, y) (*(int *)xyarray__entry(e->core.fd, x, y))
767 
768 int evsel__hwmon_pmu_open(struct evsel *evsel,
769 			  struct perf_thread_map *threads,
770 			  int start_cpu_map_idx, int end_cpu_map_idx)
771 {
772 	struct hwmon_pmu *hwm = container_of(evsel->pmu, struct hwmon_pmu, pmu);
773 	union hwmon_pmu_event_key key = {
774 		.type_and_num = evsel->core.attr.config,
775 	};
776 	int idx = 0, thread = 0, nthreads, err = 0;
777 
778 	nthreads = perf_thread_map__nr(threads);
779 	for (idx = start_cpu_map_idx; idx < end_cpu_map_idx; idx++) {
780 		for (thread = 0; thread < nthreads; thread++) {
781 			char buf[64];
782 			int fd;
783 
784 			snprintf(buf, sizeof(buf), "%s%d_input",
785 				 hwmon_type_strs[key.type], key.num);
786 
787 			fd = openat(hwm->hwmon_dir_fd, buf, O_RDONLY);
788 			FD(evsel, idx, thread) = fd;
789 			if (fd < 0) {
790 				err = -errno;
791 				goto out_close;
792 			}
793 		}
794 	}
795 	return 0;
796 out_close:
797 	if (err)
798 		threads->err_thread = thread;
799 
800 	do {
801 		while (--thread >= 0) {
802 			if (FD(evsel, idx, thread) >= 0)
803 				close(FD(evsel, idx, thread));
804 			FD(evsel, idx, thread) = -1;
805 		}
806 		thread = nthreads;
807 	} while (--idx >= 0);
808 	return err;
809 }
810 
811 int evsel__hwmon_pmu_read(struct evsel *evsel, int cpu_map_idx, int thread)
812 {
813 	char buf[32];
814 	int fd;
815 	ssize_t len;
816 	struct perf_counts_values *count, *old_count = NULL;
817 
818 	if (evsel->prev_raw_counts)
819 		old_count = perf_counts(evsel->prev_raw_counts, cpu_map_idx, thread);
820 
821 	count = perf_counts(evsel->counts, cpu_map_idx, thread);
822 	fd = FD(evsel, cpu_map_idx, thread);
823 	len = pread(fd, buf, sizeof(buf), 0);
824 	if (len <= 0) {
825 		count->lost++;
826 		return -EINVAL;
827 	}
828 	buf[len] = '\0';
829 	if (old_count) {
830 		count->val = old_count->val + strtoll(buf, NULL, 10);
831 		count->run = old_count->run + 1;
832 		count->ena = old_count->ena + 1;
833 	} else {
834 		count->val = strtoll(buf, NULL, 10);
835 		count->run++;
836 		count->ena++;
837 	}
838 	return 0;
839 }
840