xref: /linux/tools/perf/util/cpumap.c (revision 64b14a184e83eb62ea0615e31a409956049d40e7)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <api/fs/fs.h>
3 #include "cpumap.h"
4 #include "debug.h"
5 #include "event.h"
6 #include <assert.h>
7 #include <dirent.h>
8 #include <stdio.h>
9 #include <stdlib.h>
10 #include <linux/bitmap.h>
11 #include "asm/bug.h"
12 
13 #include <linux/ctype.h>
14 #include <linux/zalloc.h>
15 
16 static struct perf_cpu max_cpu_num;
17 static struct perf_cpu max_present_cpu_num;
18 static int max_node_num;
19 /**
20  * The numa node X as read from /sys/devices/system/node/nodeX indexed by the
21  * CPU number.
22  */
23 static int *cpunode_map;
24 
25 static struct perf_cpu_map *cpu_map__from_entries(struct cpu_map_entries *cpus)
26 {
27 	struct perf_cpu_map *map;
28 
29 	map = perf_cpu_map__empty_new(cpus->nr);
30 	if (map) {
31 		unsigned i;
32 
33 		for (i = 0; i < cpus->nr; i++) {
34 			/*
35 			 * Special treatment for -1, which is not real cpu number,
36 			 * and we need to use (int) -1 to initialize map[i],
37 			 * otherwise it would become 65535.
38 			 */
39 			if (cpus->cpu[i] == (u16) -1)
40 				map->map[i].cpu = -1;
41 			else
42 				map->map[i].cpu = (int) cpus->cpu[i];
43 		}
44 	}
45 
46 	return map;
47 }
48 
49 static struct perf_cpu_map *cpu_map__from_mask(struct perf_record_record_cpu_map *mask)
50 {
51 	struct perf_cpu_map *map;
52 	int nr, nbits = mask->nr * mask->long_size * BITS_PER_BYTE;
53 
54 	nr = bitmap_weight(mask->mask, nbits);
55 
56 	map = perf_cpu_map__empty_new(nr);
57 	if (map) {
58 		int cpu, i = 0;
59 
60 		for_each_set_bit(cpu, mask->mask, nbits)
61 			map->map[i++].cpu = cpu;
62 	}
63 	return map;
64 
65 }
66 
67 struct perf_cpu_map *cpu_map__new_data(struct perf_record_cpu_map_data *data)
68 {
69 	if (data->type == PERF_CPU_MAP__CPUS)
70 		return cpu_map__from_entries((struct cpu_map_entries *)data->data);
71 	else
72 		return cpu_map__from_mask((struct perf_record_record_cpu_map *)data->data);
73 }
74 
75 size_t cpu_map__fprintf(struct perf_cpu_map *map, FILE *fp)
76 {
77 #define BUFSIZE 1024
78 	char buf[BUFSIZE];
79 
80 	cpu_map__snprint(map, buf, sizeof(buf));
81 	return fprintf(fp, "%s\n", buf);
82 #undef BUFSIZE
83 }
84 
85 struct perf_cpu_map *perf_cpu_map__empty_new(int nr)
86 {
87 	struct perf_cpu_map *cpus = malloc(sizeof(*cpus) + sizeof(int) * nr);
88 
89 	if (cpus != NULL) {
90 		int i;
91 
92 		cpus->nr = nr;
93 		for (i = 0; i < nr; i++)
94 			cpus->map[i].cpu = -1;
95 
96 		refcount_set(&cpus->refcnt, 1);
97 	}
98 
99 	return cpus;
100 }
101 
102 struct cpu_aggr_map *cpu_aggr_map__empty_new(int nr)
103 {
104 	struct cpu_aggr_map *cpus = malloc(sizeof(*cpus) + sizeof(struct aggr_cpu_id) * nr);
105 
106 	if (cpus != NULL) {
107 		int i;
108 
109 		cpus->nr = nr;
110 		for (i = 0; i < nr; i++)
111 			cpus->map[i] = aggr_cpu_id__empty();
112 
113 		refcount_set(&cpus->refcnt, 1);
114 	}
115 
116 	return cpus;
117 }
118 
119 static int cpu__get_topology_int(int cpu, const char *name, int *value)
120 {
121 	char path[PATH_MAX];
122 
123 	snprintf(path, PATH_MAX,
124 		"devices/system/cpu/cpu%d/topology/%s", cpu, name);
125 
126 	return sysfs__read_int(path, value);
127 }
128 
129 int cpu__get_socket_id(struct perf_cpu cpu)
130 {
131 	int value, ret = cpu__get_topology_int(cpu.cpu, "physical_package_id", &value);
132 	return ret ?: value;
133 }
134 
135 struct aggr_cpu_id aggr_cpu_id__socket(struct perf_cpu cpu, void *data __maybe_unused)
136 {
137 	struct aggr_cpu_id id = aggr_cpu_id__empty();
138 
139 	id.socket = cpu__get_socket_id(cpu);
140 	return id;
141 }
142 
143 static int aggr_cpu_id__cmp(const void *a_pointer, const void *b_pointer)
144 {
145 	struct aggr_cpu_id *a = (struct aggr_cpu_id *)a_pointer;
146 	struct aggr_cpu_id *b = (struct aggr_cpu_id *)b_pointer;
147 
148 	if (a->node != b->node)
149 		return a->node - b->node;
150 	else if (a->socket != b->socket)
151 		return a->socket - b->socket;
152 	else if (a->die != b->die)
153 		return a->die - b->die;
154 	else if (a->core != b->core)
155 		return a->core - b->core;
156 	else
157 		return a->thread - b->thread;
158 }
159 
160 struct cpu_aggr_map *cpu_aggr_map__new(const struct perf_cpu_map *cpus,
161 				       aggr_cpu_id_get_t get_id,
162 				       void *data)
163 {
164 	int idx;
165 	struct perf_cpu cpu;
166 	struct cpu_aggr_map *c = cpu_aggr_map__empty_new(cpus->nr);
167 
168 	if (!c)
169 		return NULL;
170 
171 	/* Reset size as it may only be partially filled */
172 	c->nr = 0;
173 
174 	perf_cpu_map__for_each_cpu(cpu, idx, cpus) {
175 		bool duplicate = false;
176 		struct aggr_cpu_id cpu_id = get_id(cpu, data);
177 
178 		for (int j = 0; j < c->nr; j++) {
179 			if (aggr_cpu_id__equal(&cpu_id, &c->map[j])) {
180 				duplicate = true;
181 				break;
182 			}
183 		}
184 		if (!duplicate) {
185 			c->map[c->nr] = cpu_id;
186 			c->nr++;
187 		}
188 	}
189 	/* Trim. */
190 	if (c->nr != cpus->nr) {
191 		struct cpu_aggr_map *trimmed_c =
192 			realloc(c,
193 				sizeof(struct cpu_aggr_map) + sizeof(struct aggr_cpu_id) * c->nr);
194 
195 		if (trimmed_c)
196 			c = trimmed_c;
197 	}
198 	/* ensure we process id in increasing order */
199 	qsort(c->map, c->nr, sizeof(struct aggr_cpu_id), aggr_cpu_id__cmp);
200 
201 	return c;
202 
203 }
204 
205 int cpu__get_die_id(struct perf_cpu cpu)
206 {
207 	int value, ret = cpu__get_topology_int(cpu.cpu, "die_id", &value);
208 
209 	return ret ?: value;
210 }
211 
212 struct aggr_cpu_id aggr_cpu_id__die(struct perf_cpu cpu, void *data)
213 {
214 	struct aggr_cpu_id id;
215 	int die;
216 
217 	die = cpu__get_die_id(cpu);
218 	/* There is no die_id on legacy system. */
219 	if (die == -1)
220 		die = 0;
221 
222 	/*
223 	 * die_id is relative to socket, so start
224 	 * with the socket ID and then add die to
225 	 * make a unique ID.
226 	 */
227 	id = aggr_cpu_id__socket(cpu, data);
228 	if (aggr_cpu_id__is_empty(&id))
229 		return id;
230 
231 	id.die = die;
232 	return id;
233 }
234 
235 int cpu__get_core_id(struct perf_cpu cpu)
236 {
237 	int value, ret = cpu__get_topology_int(cpu.cpu, "core_id", &value);
238 	return ret ?: value;
239 }
240 
241 struct aggr_cpu_id aggr_cpu_id__core(struct perf_cpu cpu, void *data)
242 {
243 	struct aggr_cpu_id id;
244 	int core = cpu__get_core_id(cpu);
245 
246 	/* aggr_cpu_id__die returns a struct with socket and die set. */
247 	id = aggr_cpu_id__die(cpu, data);
248 	if (aggr_cpu_id__is_empty(&id))
249 		return id;
250 
251 	/*
252 	 * core_id is relative to socket and die, we need a global id.
253 	 * So we combine the result from cpu_map__get_die with the core id
254 	 */
255 	id.core = core;
256 	return id;
257 
258 }
259 
260 struct aggr_cpu_id aggr_cpu_id__cpu(struct perf_cpu cpu, void *data)
261 {
262 	struct aggr_cpu_id id;
263 
264 	/* aggr_cpu_id__core returns a struct with socket, die and core set. */
265 	id = aggr_cpu_id__core(cpu, data);
266 	if (aggr_cpu_id__is_empty(&id))
267 		return id;
268 
269 	id.cpu = cpu;
270 	return id;
271 
272 }
273 
274 struct aggr_cpu_id aggr_cpu_id__node(struct perf_cpu cpu, void *data __maybe_unused)
275 {
276 	struct aggr_cpu_id id = aggr_cpu_id__empty();
277 
278 	id.node = cpu__get_node(cpu);
279 	return id;
280 }
281 
282 /* setup simple routines to easily access node numbers given a cpu number */
283 static int get_max_num(char *path, int *max)
284 {
285 	size_t num;
286 	char *buf;
287 	int err = 0;
288 
289 	if (filename__read_str(path, &buf, &num))
290 		return -1;
291 
292 	buf[num] = '\0';
293 
294 	/* start on the right, to find highest node num */
295 	while (--num) {
296 		if ((buf[num] == ',') || (buf[num] == '-')) {
297 			num++;
298 			break;
299 		}
300 	}
301 	if (sscanf(&buf[num], "%d", max) < 1) {
302 		err = -1;
303 		goto out;
304 	}
305 
306 	/* convert from 0-based to 1-based */
307 	(*max)++;
308 
309 out:
310 	free(buf);
311 	return err;
312 }
313 
314 /* Determine highest possible cpu in the system for sparse allocation */
315 static void set_max_cpu_num(void)
316 {
317 	const char *mnt;
318 	char path[PATH_MAX];
319 	int ret = -1;
320 
321 	/* set up default */
322 	max_cpu_num.cpu = 4096;
323 	max_present_cpu_num.cpu = 4096;
324 
325 	mnt = sysfs__mountpoint();
326 	if (!mnt)
327 		goto out;
328 
329 	/* get the highest possible cpu number for a sparse allocation */
330 	ret = snprintf(path, PATH_MAX, "%s/devices/system/cpu/possible", mnt);
331 	if (ret >= PATH_MAX) {
332 		pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
333 		goto out;
334 	}
335 
336 	ret = get_max_num(path, &max_cpu_num.cpu);
337 	if (ret)
338 		goto out;
339 
340 	/* get the highest present cpu number for a sparse allocation */
341 	ret = snprintf(path, PATH_MAX, "%s/devices/system/cpu/present", mnt);
342 	if (ret >= PATH_MAX) {
343 		pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
344 		goto out;
345 	}
346 
347 	ret = get_max_num(path, &max_present_cpu_num.cpu);
348 
349 out:
350 	if (ret)
351 		pr_err("Failed to read max cpus, using default of %d\n", max_cpu_num.cpu);
352 }
353 
354 /* Determine highest possible node in the system for sparse allocation */
355 static void set_max_node_num(void)
356 {
357 	const char *mnt;
358 	char path[PATH_MAX];
359 	int ret = -1;
360 
361 	/* set up default */
362 	max_node_num = 8;
363 
364 	mnt = sysfs__mountpoint();
365 	if (!mnt)
366 		goto out;
367 
368 	/* get the highest possible cpu number for a sparse allocation */
369 	ret = snprintf(path, PATH_MAX, "%s/devices/system/node/possible", mnt);
370 	if (ret >= PATH_MAX) {
371 		pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
372 		goto out;
373 	}
374 
375 	ret = get_max_num(path, &max_node_num);
376 
377 out:
378 	if (ret)
379 		pr_err("Failed to read max nodes, using default of %d\n", max_node_num);
380 }
381 
382 int cpu__max_node(void)
383 {
384 	if (unlikely(!max_node_num))
385 		set_max_node_num();
386 
387 	return max_node_num;
388 }
389 
390 struct perf_cpu cpu__max_cpu(void)
391 {
392 	if (unlikely(!max_cpu_num.cpu))
393 		set_max_cpu_num();
394 
395 	return max_cpu_num;
396 }
397 
398 struct perf_cpu cpu__max_present_cpu(void)
399 {
400 	if (unlikely(!max_present_cpu_num.cpu))
401 		set_max_cpu_num();
402 
403 	return max_present_cpu_num;
404 }
405 
406 
407 int cpu__get_node(struct perf_cpu cpu)
408 {
409 	if (unlikely(cpunode_map == NULL)) {
410 		pr_debug("cpu_map not initialized\n");
411 		return -1;
412 	}
413 
414 	return cpunode_map[cpu.cpu];
415 }
416 
417 static int init_cpunode_map(void)
418 {
419 	int i;
420 
421 	set_max_cpu_num();
422 	set_max_node_num();
423 
424 	cpunode_map = calloc(max_cpu_num.cpu, sizeof(int));
425 	if (!cpunode_map) {
426 		pr_err("%s: calloc failed\n", __func__);
427 		return -1;
428 	}
429 
430 	for (i = 0; i < max_cpu_num.cpu; i++)
431 		cpunode_map[i] = -1;
432 
433 	return 0;
434 }
435 
436 int cpu__setup_cpunode_map(void)
437 {
438 	struct dirent *dent1, *dent2;
439 	DIR *dir1, *dir2;
440 	unsigned int cpu, mem;
441 	char buf[PATH_MAX];
442 	char path[PATH_MAX];
443 	const char *mnt;
444 	int n;
445 
446 	/* initialize globals */
447 	if (init_cpunode_map())
448 		return -1;
449 
450 	mnt = sysfs__mountpoint();
451 	if (!mnt)
452 		return 0;
453 
454 	n = snprintf(path, PATH_MAX, "%s/devices/system/node", mnt);
455 	if (n >= PATH_MAX) {
456 		pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
457 		return -1;
458 	}
459 
460 	dir1 = opendir(path);
461 	if (!dir1)
462 		return 0;
463 
464 	/* walk tree and setup map */
465 	while ((dent1 = readdir(dir1)) != NULL) {
466 		if (dent1->d_type != DT_DIR || sscanf(dent1->d_name, "node%u", &mem) < 1)
467 			continue;
468 
469 		n = snprintf(buf, PATH_MAX, "%s/%s", path, dent1->d_name);
470 		if (n >= PATH_MAX) {
471 			pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
472 			continue;
473 		}
474 
475 		dir2 = opendir(buf);
476 		if (!dir2)
477 			continue;
478 		while ((dent2 = readdir(dir2)) != NULL) {
479 			if (dent2->d_type != DT_LNK || sscanf(dent2->d_name, "cpu%u", &cpu) < 1)
480 				continue;
481 			cpunode_map[cpu] = mem;
482 		}
483 		closedir(dir2);
484 	}
485 	closedir(dir1);
486 	return 0;
487 }
488 
489 size_t cpu_map__snprint(struct perf_cpu_map *map, char *buf, size_t size)
490 {
491 	int i, start = -1;
492 	bool first = true;
493 	size_t ret = 0;
494 
495 #define COMMA first ? "" : ","
496 
497 	for (i = 0; i < map->nr + 1; i++) {
498 		struct perf_cpu cpu = { .cpu = INT_MAX };
499 		bool last = i == map->nr;
500 
501 		if (!last)
502 			cpu = map->map[i];
503 
504 		if (start == -1) {
505 			start = i;
506 			if (last) {
507 				ret += snprintf(buf + ret, size - ret,
508 						"%s%d", COMMA,
509 						map->map[i].cpu);
510 			}
511 		} else if (((i - start) != (cpu.cpu - map->map[start].cpu)) || last) {
512 			int end = i - 1;
513 
514 			if (start == end) {
515 				ret += snprintf(buf + ret, size - ret,
516 						"%s%d", COMMA,
517 						map->map[start].cpu);
518 			} else {
519 				ret += snprintf(buf + ret, size - ret,
520 						"%s%d-%d", COMMA,
521 						map->map[start].cpu, map->map[end].cpu);
522 			}
523 			first = false;
524 			start = i;
525 		}
526 	}
527 
528 #undef COMMA
529 
530 	pr_debug2("cpumask list: %s\n", buf);
531 	return ret;
532 }
533 
534 static char hex_char(unsigned char val)
535 {
536 	if (val < 10)
537 		return val + '0';
538 	if (val < 16)
539 		return val - 10 + 'a';
540 	return '?';
541 }
542 
543 size_t cpu_map__snprint_mask(struct perf_cpu_map *map, char *buf, size_t size)
544 {
545 	int i, cpu;
546 	char *ptr = buf;
547 	unsigned char *bitmap;
548 	struct perf_cpu last_cpu = perf_cpu_map__cpu(map, map->nr - 1);
549 
550 	if (buf == NULL)
551 		return 0;
552 
553 	bitmap = zalloc(last_cpu.cpu / 8 + 1);
554 	if (bitmap == NULL) {
555 		buf[0] = '\0';
556 		return 0;
557 	}
558 
559 	for (i = 0; i < map->nr; i++) {
560 		cpu = perf_cpu_map__cpu(map, i).cpu;
561 		bitmap[cpu / 8] |= 1 << (cpu % 8);
562 	}
563 
564 	for (cpu = last_cpu.cpu / 4 * 4; cpu >= 0; cpu -= 4) {
565 		unsigned char bits = bitmap[cpu / 8];
566 
567 		if (cpu % 8)
568 			bits >>= 4;
569 		else
570 			bits &= 0xf;
571 
572 		*ptr++ = hex_char(bits);
573 		if ((cpu % 32) == 0 && cpu > 0)
574 			*ptr++ = ',';
575 	}
576 	*ptr = '\0';
577 	free(bitmap);
578 
579 	buf[size - 1] = '\0';
580 	return ptr - buf;
581 }
582 
583 const struct perf_cpu_map *cpu_map__online(void) /* thread unsafe */
584 {
585 	static const struct perf_cpu_map *online = NULL;
586 
587 	if (!online)
588 		online = perf_cpu_map__new(NULL); /* from /sys/devices/system/cpu/online */
589 
590 	return online;
591 }
592 
593 bool aggr_cpu_id__equal(const struct aggr_cpu_id *a, const struct aggr_cpu_id *b)
594 {
595 	return a->thread == b->thread &&
596 		a->node == b->node &&
597 		a->socket == b->socket &&
598 		a->die == b->die &&
599 		a->core == b->core &&
600 		a->cpu.cpu == b->cpu.cpu;
601 }
602 
603 bool aggr_cpu_id__is_empty(const struct aggr_cpu_id *a)
604 {
605 	return a->thread == -1 &&
606 		a->node == -1 &&
607 		a->socket == -1 &&
608 		a->die == -1 &&
609 		a->core == -1 &&
610 		a->cpu.cpu == -1;
611 }
612 
613 struct aggr_cpu_id aggr_cpu_id__empty(void)
614 {
615 	struct aggr_cpu_id ret = {
616 		.thread = -1,
617 		.node = -1,
618 		.socket = -1,
619 		.die = -1,
620 		.core = -1,
621 		.cpu = (struct perf_cpu){ .cpu = -1 },
622 	};
623 	return ret;
624 }
625