xref: /linux/tools/perf/util/pmus.c (revision 53fc25b7f557089aff101235152ae4bff15c428a)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/list.h>
3 #include <linux/zalloc.h>
4 #include <subcmd/pager.h>
5 #include <sys/types.h>
6 #include <dirent.h>
7 #include <pthread.h>
8 #include <string.h>
9 #include <unistd.h>
10 #include "debug.h"
11 #include "evsel.h"
12 #include "pmus.h"
13 #include "pmu.h"
14 #include "print-events.h"
15 
16 /*
17  * core_pmus:  A PMU belongs to core_pmus if it's name is "cpu" or it's sysfs
18  *             directory contains "cpus" file. All PMUs belonging to core_pmus
19  *             must have pmu->is_core=1. If there are more than one PMU in
20  *             this list, perf interprets it as a heterogeneous platform.
21  *             (FWIW, certain ARM platforms having heterogeneous cores uses
22  *             homogeneous PMU, and thus they are treated as homogeneous
23  *             platform by perf because core_pmus will have only one entry)
24  * other_pmus: All other PMUs which are not part of core_pmus list. It doesn't
25  *             matter whether PMU is present per SMT-thread or outside of the
26  *             core in the hw. For e.g., an instance of AMD ibs_fetch// and
27  *             ibs_op// PMUs is present in each hw SMT thread, however they
28  *             are captured under other_pmus. PMUs belonging to other_pmus
29  *             must have pmu->is_core=0 but pmu->is_uncore could be 0 or 1.
30  */
31 static LIST_HEAD(core_pmus);
32 static LIST_HEAD(other_pmus);
33 static bool read_sysfs_core_pmus;
34 static bool read_sysfs_all_pmus;
35 
36 void perf_pmus__destroy(void)
37 {
38 	struct perf_pmu *pmu, *tmp;
39 
40 	list_for_each_entry_safe(pmu, tmp, &core_pmus, list) {
41 		list_del(&pmu->list);
42 
43 		perf_pmu__delete(pmu);
44 	}
45 	list_for_each_entry_safe(pmu, tmp, &other_pmus, list) {
46 		list_del(&pmu->list);
47 
48 		perf_pmu__delete(pmu);
49 	}
50 	read_sysfs_core_pmus = false;
51 	read_sysfs_all_pmus = false;
52 }
53 
54 static struct perf_pmu *pmu_find(const char *name)
55 {
56 	struct perf_pmu *pmu;
57 
58 	list_for_each_entry(pmu, &core_pmus, list) {
59 		if (!strcmp(pmu->name, name) ||
60 		    (pmu->alias_name && !strcmp(pmu->alias_name, name)))
61 			return pmu;
62 	}
63 	list_for_each_entry(pmu, &other_pmus, list) {
64 		if (!strcmp(pmu->name, name) ||
65 		    (pmu->alias_name && !strcmp(pmu->alias_name, name)))
66 			return pmu;
67 	}
68 
69 	return NULL;
70 }
71 
72 struct perf_pmu *perf_pmus__find(const char *name)
73 {
74 	struct perf_pmu *pmu;
75 	int dirfd;
76 	bool core_pmu;
77 
78 	/*
79 	 * Once PMU is loaded it stays in the list,
80 	 * so we keep us from multiple reading/parsing
81 	 * the pmu format definitions.
82 	 */
83 	pmu = pmu_find(name);
84 	if (pmu)
85 		return pmu;
86 
87 	if (read_sysfs_all_pmus)
88 		return NULL;
89 
90 	core_pmu = is_pmu_core(name);
91 	if (core_pmu && read_sysfs_core_pmus)
92 		return NULL;
93 
94 	dirfd = perf_pmu__event_source_devices_fd();
95 	pmu = perf_pmu__lookup(core_pmu ? &core_pmus : &other_pmus, dirfd, name);
96 	close(dirfd);
97 
98 	return pmu;
99 }
100 
101 static struct perf_pmu *perf_pmu__find2(int dirfd, const char *name)
102 {
103 	struct perf_pmu *pmu;
104 	bool core_pmu;
105 
106 	/*
107 	 * Once PMU is loaded it stays in the list,
108 	 * so we keep us from multiple reading/parsing
109 	 * the pmu format definitions.
110 	 */
111 	pmu = pmu_find(name);
112 	if (pmu)
113 		return pmu;
114 
115 	if (read_sysfs_all_pmus)
116 		return NULL;
117 
118 	core_pmu = is_pmu_core(name);
119 	if (core_pmu && read_sysfs_core_pmus)
120 		return NULL;
121 
122 	return perf_pmu__lookup(core_pmu ? &core_pmus : &other_pmus, dirfd, name);
123 }
124 
125 /* Add all pmus in sysfs to pmu list: */
126 static void pmu_read_sysfs(bool core_only)
127 {
128 	int fd;
129 	DIR *dir;
130 	struct dirent *dent;
131 
132 	if (read_sysfs_all_pmus || (core_only && read_sysfs_core_pmus))
133 		return;
134 
135 	fd = perf_pmu__event_source_devices_fd();
136 	if (fd < 0)
137 		return;
138 
139 	dir = fdopendir(fd);
140 	if (!dir)
141 		return;
142 
143 	while ((dent = readdir(dir))) {
144 		if (!strcmp(dent->d_name, ".") || !strcmp(dent->d_name, ".."))
145 			continue;
146 		if (core_only && !is_pmu_core(dent->d_name))
147 			continue;
148 		/* add to static LIST_HEAD(core_pmus) or LIST_HEAD(other_pmus): */
149 		perf_pmu__find2(fd, dent->d_name);
150 	}
151 
152 	closedir(dir);
153 	if (core_only) {
154 		read_sysfs_core_pmus = true;
155 	} else {
156 		read_sysfs_core_pmus = true;
157 		read_sysfs_all_pmus = true;
158 	}
159 }
160 
161 static struct perf_pmu *__perf_pmus__find_by_type(unsigned int type)
162 {
163 	struct perf_pmu *pmu;
164 
165 	list_for_each_entry(pmu, &core_pmus, list) {
166 		if (pmu->type == type)
167 			return pmu;
168 	}
169 
170 	list_for_each_entry(pmu, &other_pmus, list) {
171 		if (pmu->type == type)
172 			return pmu;
173 	}
174 	return NULL;
175 }
176 
177 struct perf_pmu *perf_pmus__find_by_type(unsigned int type)
178 {
179 	struct perf_pmu *pmu = __perf_pmus__find_by_type(type);
180 
181 	if (pmu || read_sysfs_all_pmus)
182 		return pmu;
183 
184 	pmu_read_sysfs(/*core_only=*/false);
185 	pmu = __perf_pmus__find_by_type(type);
186 	return pmu;
187 }
188 
189 /*
190  * pmu iterator: If pmu is NULL, we start at the begin, otherwise return the
191  * next pmu. Returns NULL on end.
192  */
193 struct perf_pmu *perf_pmus__scan(struct perf_pmu *pmu)
194 {
195 	bool use_core_pmus = !pmu || pmu->is_core;
196 
197 	if (!pmu) {
198 		pmu_read_sysfs(/*core_only=*/false);
199 		pmu = list_prepare_entry(pmu, &core_pmus, list);
200 	}
201 	if (use_core_pmus) {
202 		list_for_each_entry_continue(pmu, &core_pmus, list)
203 			return pmu;
204 
205 		pmu = NULL;
206 		pmu = list_prepare_entry(pmu, &other_pmus, list);
207 	}
208 	list_for_each_entry_continue(pmu, &other_pmus, list)
209 		return pmu;
210 	return NULL;
211 }
212 
213 struct perf_pmu *perf_pmus__scan_core(struct perf_pmu *pmu)
214 {
215 	if (!pmu) {
216 		pmu_read_sysfs(/*core_only=*/true);
217 		pmu = list_prepare_entry(pmu, &core_pmus, list);
218 	}
219 	list_for_each_entry_continue(pmu, &core_pmus, list)
220 		return pmu;
221 
222 	return NULL;
223 }
224 
225 const struct perf_pmu *perf_pmus__pmu_for_pmu_filter(const char *str)
226 {
227 	struct perf_pmu *pmu = NULL;
228 
229 	while ((pmu = perf_pmus__scan(pmu)) != NULL) {
230 		if (!strcmp(pmu->name, str))
231 			return pmu;
232 		/* Ignore "uncore_" prefix. */
233 		if (!strncmp(pmu->name, "uncore_", 7)) {
234 			if (!strcmp(pmu->name + 7, str))
235 				return pmu;
236 		}
237 		/* Ignore "cpu_" prefix on Intel hybrid PMUs. */
238 		if (!strncmp(pmu->name, "cpu_", 4)) {
239 			if (!strcmp(pmu->name + 4, str))
240 				return pmu;
241 		}
242 	}
243 	return NULL;
244 }
245 
246 int __weak perf_pmus__num_mem_pmus(void)
247 {
248 	/* All core PMUs are for mem events. */
249 	return perf_pmus__num_core_pmus();
250 }
251 
252 /** Struct for ordering events as output in perf list. */
253 struct sevent {
254 	/** PMU for event. */
255 	const struct perf_pmu *pmu;
256 	/**
257 	 * Optional event for name, desc, etc. If not present then this is a
258 	 * selectable PMU and the event name is shown as "//".
259 	 */
260 	const struct perf_pmu_alias *event;
261 	/** Is the PMU for the CPU? */
262 	bool is_cpu;
263 };
264 
265 static int cmp_sevent(const void *a, const void *b)
266 {
267 	const struct sevent *as = a;
268 	const struct sevent *bs = b;
269 	const char *a_pmu_name = NULL, *b_pmu_name = NULL;
270 	const char *a_name = "//", *a_desc = NULL, *a_topic = "";
271 	const char *b_name = "//", *b_desc = NULL, *b_topic = "";
272 	int ret;
273 
274 	if (as->event) {
275 		a_name = as->event->name;
276 		a_desc = as->event->desc;
277 		a_topic = as->event->topic ?: "";
278 		a_pmu_name = as->event->pmu_name;
279 	}
280 	if (bs->event) {
281 		b_name = bs->event->name;
282 		b_desc = bs->event->desc;
283 		b_topic = bs->event->topic ?: "";
284 		b_pmu_name = bs->event->pmu_name;
285 	}
286 	/* Put extra events last. */
287 	if (!!a_desc != !!b_desc)
288 		return !!a_desc - !!b_desc;
289 
290 	/* Order by topics. */
291 	ret = strcmp(a_topic, b_topic);
292 	if (ret)
293 		return ret;
294 
295 	/* Order CPU core events to be first */
296 	if (as->is_cpu != bs->is_cpu)
297 		return as->is_cpu ? -1 : 1;
298 
299 	/* Order by PMU name. */
300 	if (as->pmu != bs->pmu) {
301 		a_pmu_name = a_pmu_name ?: (as->pmu->name ?: "");
302 		b_pmu_name = b_pmu_name ?: (bs->pmu->name ?: "");
303 		ret = strcmp(a_pmu_name, b_pmu_name);
304 		if (ret)
305 			return ret;
306 	}
307 
308 	/* Order by event name. */
309 	return strcmp(a_name, b_name);
310 }
311 
312 static bool pmu_alias_is_duplicate(struct sevent *alias_a,
313 				   struct sevent *alias_b)
314 {
315 	const char *a_pmu_name = NULL, *b_pmu_name = NULL;
316 	const char *a_name = "//", *b_name = "//";
317 
318 
319 	if (alias_a->event) {
320 		a_name = alias_a->event->name;
321 		a_pmu_name = alias_a->event->pmu_name;
322 	}
323 	if (alias_b->event) {
324 		b_name = alias_b->event->name;
325 		b_pmu_name = alias_b->event->pmu_name;
326 	}
327 
328 	/* Different names -> never duplicates */
329 	if (strcmp(a_name, b_name))
330 		return false;
331 
332 	/* Don't remove duplicates for different PMUs */
333 	a_pmu_name = a_pmu_name ?: (alias_a->pmu->name ?: "");
334 	b_pmu_name = b_pmu_name ?: (alias_b->pmu->name ?: "");
335 	return strcmp(a_pmu_name, b_pmu_name) == 0;
336 }
337 
338 static int sub_non_neg(int a, int b)
339 {
340 	if (b > a)
341 		return 0;
342 	return a - b;
343 }
344 
345 static char *format_alias(char *buf, int len, const struct perf_pmu *pmu,
346 			  const struct perf_pmu_alias *alias)
347 {
348 	struct parse_events_term *term;
349 	int used = snprintf(buf, len, "%s/%s", pmu->name, alias->name);
350 
351 	list_for_each_entry(term, &alias->terms, list) {
352 		if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR)
353 			used += snprintf(buf + used, sub_non_neg(len, used),
354 					",%s=%s", term->config,
355 					term->val.str);
356 	}
357 
358 	if (sub_non_neg(len, used) > 0) {
359 		buf[used] = '/';
360 		used++;
361 	}
362 	if (sub_non_neg(len, used) > 0) {
363 		buf[used] = '\0';
364 		used++;
365 	} else
366 		buf[len - 1] = '\0';
367 
368 	return buf;
369 }
370 
371 void perf_pmus__print_pmu_events(const struct print_callbacks *print_cb, void *print_state)
372 {
373 	struct perf_pmu *pmu;
374 	struct perf_pmu_alias *event;
375 	char buf[1024];
376 	int printed = 0;
377 	int len, j;
378 	struct sevent *aliases;
379 
380 	pmu = NULL;
381 	len = 0;
382 	while ((pmu = perf_pmus__scan(pmu)) != NULL) {
383 		list_for_each_entry(event, &pmu->aliases, list)
384 			len++;
385 		if (pmu->selectable)
386 			len++;
387 	}
388 	aliases = zalloc(sizeof(struct sevent) * len);
389 	if (!aliases) {
390 		pr_err("FATAL: not enough memory to print PMU events\n");
391 		return;
392 	}
393 	pmu = NULL;
394 	j = 0;
395 	while ((pmu = perf_pmus__scan(pmu)) != NULL) {
396 		bool is_cpu = pmu->is_core;
397 
398 		list_for_each_entry(event, &pmu->aliases, list) {
399 			aliases[j].event = event;
400 			aliases[j].pmu = pmu;
401 			aliases[j].is_cpu = is_cpu;
402 			j++;
403 		}
404 		if (pmu->selectable) {
405 			aliases[j].event = NULL;
406 			aliases[j].pmu = pmu;
407 			aliases[j].is_cpu = is_cpu;
408 			j++;
409 		}
410 	}
411 	len = j;
412 	qsort(aliases, len, sizeof(struct sevent), cmp_sevent);
413 	for (j = 0; j < len; j++) {
414 		const char *name, *alias = NULL, *scale_unit = NULL,
415 			*desc = NULL, *long_desc = NULL,
416 			*encoding_desc = NULL, *topic = NULL,
417 			*pmu_name = NULL;
418 		bool deprecated = false;
419 		size_t buf_used;
420 
421 		/* Skip duplicates */
422 		if (j > 0 && pmu_alias_is_duplicate(&aliases[j], &aliases[j - 1]))
423 			continue;
424 
425 		if (!aliases[j].event) {
426 			/* A selectable event. */
427 			pmu_name = aliases[j].pmu->name;
428 			buf_used = snprintf(buf, sizeof(buf), "%s//", pmu_name) + 1;
429 			name = buf;
430 		} else {
431 			if (aliases[j].event->desc) {
432 				name = aliases[j].event->name;
433 				buf_used = 0;
434 			} else {
435 				name = format_alias(buf, sizeof(buf), aliases[j].pmu,
436 						    aliases[j].event);
437 				if (aliases[j].is_cpu) {
438 					alias = name;
439 					name = aliases[j].event->name;
440 				}
441 				buf_used = strlen(buf) + 1;
442 			}
443 			pmu_name = aliases[j].event->pmu_name ?: (aliases[j].pmu->name ?: "");
444 			if (strlen(aliases[j].event->unit) || aliases[j].event->scale != 1.0) {
445 				scale_unit = buf + buf_used;
446 				buf_used += snprintf(buf + buf_used, sizeof(buf) - buf_used,
447 						"%G%s", aliases[j].event->scale,
448 						aliases[j].event->unit) + 1;
449 			}
450 			desc = aliases[j].event->desc;
451 			long_desc = aliases[j].event->long_desc;
452 			topic = aliases[j].event->topic;
453 			encoding_desc = buf + buf_used;
454 			buf_used += snprintf(buf + buf_used, sizeof(buf) - buf_used,
455 					"%s/%s/", pmu_name, aliases[j].event->str) + 1;
456 			deprecated = aliases[j].event->deprecated;
457 		}
458 		print_cb->print_event(print_state,
459 				pmu_name,
460 				topic,
461 				name,
462 				alias,
463 				scale_unit,
464 				deprecated,
465 				"Kernel PMU event",
466 				desc,
467 				long_desc,
468 				encoding_desc);
469 	}
470 	if (printed && pager_in_use())
471 		printf("\n");
472 
473 	zfree(&aliases);
474 }
475 
476 bool perf_pmus__have_event(const char *pname, const char *name)
477 {
478 	struct perf_pmu *pmu = perf_pmus__find(pname);
479 
480 	return pmu && perf_pmu__have_event(pmu, name);
481 }
482 
483 int perf_pmus__num_core_pmus(void)
484 {
485 	static int count;
486 
487 	if (!count) {
488 		struct perf_pmu *pmu = NULL;
489 
490 		while ((pmu = perf_pmus__scan_core(pmu)) != NULL)
491 			count++;
492 	}
493 	return count;
494 }
495 
496 static bool __perf_pmus__supports_extended_type(void)
497 {
498 	struct perf_pmu *pmu = NULL;
499 
500 	if (perf_pmus__num_core_pmus() <= 1)
501 		return false;
502 
503 	while ((pmu = perf_pmus__scan_core(pmu)) != NULL) {
504 		if (!is_event_supported(PERF_TYPE_HARDWARE, PERF_COUNT_HW_CPU_CYCLES | ((__u64)pmu->type << PERF_PMU_TYPE_SHIFT)))
505 			return false;
506 	}
507 
508 	return true;
509 }
510 
511 static bool perf_pmus__do_support_extended_type;
512 
513 static void perf_pmus__init_supports_extended_type(void)
514 {
515 	perf_pmus__do_support_extended_type = __perf_pmus__supports_extended_type();
516 }
517 
518 bool perf_pmus__supports_extended_type(void)
519 {
520 	static pthread_once_t extended_type_once = PTHREAD_ONCE_INIT;
521 
522 	pthread_once(&extended_type_once, perf_pmus__init_supports_extended_type);
523 
524 	return perf_pmus__do_support_extended_type;
525 }
526 
527 struct perf_pmu *evsel__find_pmu(const struct evsel *evsel)
528 {
529 	struct perf_pmu *pmu = evsel->pmu;
530 
531 	if (!pmu) {
532 		pmu = perf_pmus__find_by_type(evsel->core.attr.type);
533 		((struct evsel *)evsel)->pmu = pmu;
534 	}
535 	return pmu;
536 }
537