xref: /openbmc/linux/tools/perf/util/cpumap.c (revision 1d05334d)
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 int max_cpu_num;
17 static int max_present_cpu_num;
18 static int max_node_num;
19 static int *cpunode_map;
20 
21 static struct perf_cpu_map *cpu_map__from_entries(struct cpu_map_entries *cpus)
22 {
23 	struct perf_cpu_map *map;
24 
25 	map = perf_cpu_map__empty_new(cpus->nr);
26 	if (map) {
27 		unsigned i;
28 
29 		for (i = 0; i < cpus->nr; i++) {
30 			/*
31 			 * Special treatment for -1, which is not real cpu number,
32 			 * and we need to use (int) -1 to initialize map[i],
33 			 * otherwise it would become 65535.
34 			 */
35 			if (cpus->cpu[i] == (u16) -1)
36 				map->map[i] = -1;
37 			else
38 				map->map[i] = (int) cpus->cpu[i];
39 		}
40 	}
41 
42 	return map;
43 }
44 
45 static struct perf_cpu_map *cpu_map__from_mask(struct perf_record_record_cpu_map *mask)
46 {
47 	struct perf_cpu_map *map;
48 	int nr, nbits = mask->nr * mask->long_size * BITS_PER_BYTE;
49 
50 	nr = bitmap_weight(mask->mask, nbits);
51 
52 	map = perf_cpu_map__empty_new(nr);
53 	if (map) {
54 		int cpu, i = 0;
55 
56 		for_each_set_bit(cpu, mask->mask, nbits)
57 			map->map[i++] = cpu;
58 	}
59 	return map;
60 
61 }
62 
63 struct perf_cpu_map *cpu_map__new_data(struct perf_record_cpu_map_data *data)
64 {
65 	if (data->type == PERF_CPU_MAP__CPUS)
66 		return cpu_map__from_entries((struct cpu_map_entries *)data->data);
67 	else
68 		return cpu_map__from_mask((struct perf_record_record_cpu_map *)data->data);
69 }
70 
71 size_t cpu_map__fprintf(struct perf_cpu_map *map, FILE *fp)
72 {
73 #define BUFSIZE 1024
74 	char buf[BUFSIZE];
75 
76 	cpu_map__snprint(map, buf, sizeof(buf));
77 	return fprintf(fp, "%s\n", buf);
78 #undef BUFSIZE
79 }
80 
81 struct perf_cpu_map *perf_cpu_map__empty_new(int nr)
82 {
83 	struct perf_cpu_map *cpus = malloc(sizeof(*cpus) + sizeof(int) * nr);
84 
85 	if (cpus != NULL) {
86 		int i;
87 
88 		cpus->nr = nr;
89 		for (i = 0; i < nr; i++)
90 			cpus->map[i] = -1;
91 
92 		refcount_set(&cpus->refcnt, 1);
93 	}
94 
95 	return cpus;
96 }
97 
98 static int cpu__get_topology_int(int cpu, const char *name, int *value)
99 {
100 	char path[PATH_MAX];
101 
102 	snprintf(path, PATH_MAX,
103 		"devices/system/cpu/cpu%d/topology/%s", cpu, name);
104 
105 	return sysfs__read_int(path, value);
106 }
107 
108 int cpu_map__get_socket_id(int cpu)
109 {
110 	int value, ret = cpu__get_topology_int(cpu, "physical_package_id", &value);
111 	return ret ?: value;
112 }
113 
114 int cpu_map__get_socket(struct perf_cpu_map *map, int idx, void *data __maybe_unused)
115 {
116 	int cpu;
117 
118 	if (idx > map->nr)
119 		return -1;
120 
121 	cpu = map->map[idx];
122 
123 	return cpu_map__get_socket_id(cpu);
124 }
125 
126 static int cmp_ids(const void *a, const void *b)
127 {
128 	return *(int *)a - *(int *)b;
129 }
130 
131 int cpu_map__build_map(struct perf_cpu_map *cpus, struct perf_cpu_map **res,
132 		       int (*f)(struct perf_cpu_map *map, int cpu, void *data),
133 		       void *data)
134 {
135 	struct perf_cpu_map *c;
136 	int nr = cpus->nr;
137 	int cpu, s1, s2;
138 
139 	/* allocate as much as possible */
140 	c = calloc(1, sizeof(*c) + nr * sizeof(int));
141 	if (!c)
142 		return -1;
143 
144 	for (cpu = 0; cpu < nr; cpu++) {
145 		s1 = f(cpus, cpu, data);
146 		for (s2 = 0; s2 < c->nr; s2++) {
147 			if (s1 == c->map[s2])
148 				break;
149 		}
150 		if (s2 == c->nr) {
151 			c->map[c->nr] = s1;
152 			c->nr++;
153 		}
154 	}
155 	/* ensure we process id in increasing order */
156 	qsort(c->map, c->nr, sizeof(int), cmp_ids);
157 
158 	refcount_set(&c->refcnt, 1);
159 	*res = c;
160 	return 0;
161 }
162 
163 int cpu_map__get_die_id(int cpu)
164 {
165 	int value, ret = cpu__get_topology_int(cpu, "die_id", &value);
166 
167 	return ret ?: value;
168 }
169 
170 int cpu_map__get_die(struct perf_cpu_map *map, int idx, void *data)
171 {
172 	int cpu, die_id, s;
173 
174 	if (idx > map->nr)
175 		return -1;
176 
177 	cpu = map->map[idx];
178 
179 	die_id = cpu_map__get_die_id(cpu);
180 	/* There is no die_id on legacy system. */
181 	if (die_id == -1)
182 		die_id = 0;
183 
184 	s = cpu_map__get_socket(map, idx, data);
185 	if (s == -1)
186 		return -1;
187 
188 	/*
189 	 * Encode socket in bit range 15:8
190 	 * die_id is relative to socket, and
191 	 * we need a global id. So we combine
192 	 * socket + die id
193 	 */
194 	if (WARN_ONCE(die_id >> 8, "The die id number is too big.\n"))
195 		return -1;
196 
197 	if (WARN_ONCE(s >> 8, "The socket id number is too big.\n"))
198 		return -1;
199 
200 	return (s << 8) | (die_id & 0xff);
201 }
202 
203 int cpu_map__get_core_id(int cpu)
204 {
205 	int value, ret = cpu__get_topology_int(cpu, "core_id", &value);
206 	return ret ?: value;
207 }
208 
209 int cpu_map__get_node_id(int cpu)
210 {
211 	return cpu__get_node(cpu);
212 }
213 
214 int cpu_map__get_core(struct perf_cpu_map *map, int idx, void *data)
215 {
216 	int cpu, s_die;
217 
218 	if (idx > map->nr)
219 		return -1;
220 
221 	cpu = map->map[idx];
222 
223 	cpu = cpu_map__get_core_id(cpu);
224 
225 	/* s_die is the combination of socket + die id */
226 	s_die = cpu_map__get_die(map, idx, data);
227 	if (s_die == -1)
228 		return -1;
229 
230 	/*
231 	 * encode socket in bit range 31:24
232 	 * encode die id in bit range 23:16
233 	 * core_id is relative to socket and die,
234 	 * we need a global id. So we combine
235 	 * socket + die id + core id
236 	 */
237 	if (WARN_ONCE(cpu >> 16, "The core id number is too big.\n"))
238 		return -1;
239 
240 	return (s_die << 16) | (cpu & 0xffff);
241 }
242 
243 int cpu_map__get_node(struct perf_cpu_map *map, int idx, void *data __maybe_unused)
244 {
245 	if (idx < 0 || idx >= map->nr)
246 		return -1;
247 
248 	return cpu_map__get_node_id(map->map[idx]);
249 }
250 
251 int cpu_map__build_socket_map(struct perf_cpu_map *cpus, struct perf_cpu_map **sockp)
252 {
253 	return cpu_map__build_map(cpus, sockp, cpu_map__get_socket, NULL);
254 }
255 
256 int cpu_map__build_die_map(struct perf_cpu_map *cpus, struct perf_cpu_map **diep)
257 {
258 	return cpu_map__build_map(cpus, diep, cpu_map__get_die, NULL);
259 }
260 
261 int cpu_map__build_core_map(struct perf_cpu_map *cpus, struct perf_cpu_map **corep)
262 {
263 	return cpu_map__build_map(cpus, corep, cpu_map__get_core, NULL);
264 }
265 
266 int cpu_map__build_node_map(struct perf_cpu_map *cpus, struct perf_cpu_map **numap)
267 {
268 	return cpu_map__build_map(cpus, numap, cpu_map__get_node, NULL);
269 }
270 
271 /* setup simple routines to easily access node numbers given a cpu number */
272 static int get_max_num(char *path, int *max)
273 {
274 	size_t num;
275 	char *buf;
276 	int err = 0;
277 
278 	if (filename__read_str(path, &buf, &num))
279 		return -1;
280 
281 	buf[num] = '\0';
282 
283 	/* start on the right, to find highest node num */
284 	while (--num) {
285 		if ((buf[num] == ',') || (buf[num] == '-')) {
286 			num++;
287 			break;
288 		}
289 	}
290 	if (sscanf(&buf[num], "%d", max) < 1) {
291 		err = -1;
292 		goto out;
293 	}
294 
295 	/* convert from 0-based to 1-based */
296 	(*max)++;
297 
298 out:
299 	free(buf);
300 	return err;
301 }
302 
303 /* Determine highest possible cpu in the system for sparse allocation */
304 static void set_max_cpu_num(void)
305 {
306 	const char *mnt;
307 	char path[PATH_MAX];
308 	int ret = -1;
309 
310 	/* set up default */
311 	max_cpu_num = 4096;
312 	max_present_cpu_num = 4096;
313 
314 	mnt = sysfs__mountpoint();
315 	if (!mnt)
316 		goto out;
317 
318 	/* get the highest possible cpu number for a sparse allocation */
319 	ret = snprintf(path, PATH_MAX, "%s/devices/system/cpu/possible", mnt);
320 	if (ret >= PATH_MAX) {
321 		pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
322 		goto out;
323 	}
324 
325 	ret = get_max_num(path, &max_cpu_num);
326 	if (ret)
327 		goto out;
328 
329 	/* get the highest present cpu number for a sparse allocation */
330 	ret = snprintf(path, PATH_MAX, "%s/devices/system/cpu/present", 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_present_cpu_num);
337 
338 out:
339 	if (ret)
340 		pr_err("Failed to read max cpus, using default of %d\n", max_cpu_num);
341 }
342 
343 /* Determine highest possible node in the system for sparse allocation */
344 static void set_max_node_num(void)
345 {
346 	const char *mnt;
347 	char path[PATH_MAX];
348 	int ret = -1;
349 
350 	/* set up default */
351 	max_node_num = 8;
352 
353 	mnt = sysfs__mountpoint();
354 	if (!mnt)
355 		goto out;
356 
357 	/* get the highest possible cpu number for a sparse allocation */
358 	ret = snprintf(path, PATH_MAX, "%s/devices/system/node/possible", mnt);
359 	if (ret >= PATH_MAX) {
360 		pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
361 		goto out;
362 	}
363 
364 	ret = get_max_num(path, &max_node_num);
365 
366 out:
367 	if (ret)
368 		pr_err("Failed to read max nodes, using default of %d\n", max_node_num);
369 }
370 
371 int cpu__max_node(void)
372 {
373 	if (unlikely(!max_node_num))
374 		set_max_node_num();
375 
376 	return max_node_num;
377 }
378 
379 int cpu__max_cpu(void)
380 {
381 	if (unlikely(!max_cpu_num))
382 		set_max_cpu_num();
383 
384 	return max_cpu_num;
385 }
386 
387 int cpu__max_present_cpu(void)
388 {
389 	if (unlikely(!max_present_cpu_num))
390 		set_max_cpu_num();
391 
392 	return max_present_cpu_num;
393 }
394 
395 
396 int cpu__get_node(int cpu)
397 {
398 	if (unlikely(cpunode_map == NULL)) {
399 		pr_debug("cpu_map not initialized\n");
400 		return -1;
401 	}
402 
403 	return cpunode_map[cpu];
404 }
405 
406 static int init_cpunode_map(void)
407 {
408 	int i;
409 
410 	set_max_cpu_num();
411 	set_max_node_num();
412 
413 	cpunode_map = calloc(max_cpu_num, sizeof(int));
414 	if (!cpunode_map) {
415 		pr_err("%s: calloc failed\n", __func__);
416 		return -1;
417 	}
418 
419 	for (i = 0; i < max_cpu_num; i++)
420 		cpunode_map[i] = -1;
421 
422 	return 0;
423 }
424 
425 int cpu__setup_cpunode_map(void)
426 {
427 	struct dirent *dent1, *dent2;
428 	DIR *dir1, *dir2;
429 	unsigned int cpu, mem;
430 	char buf[PATH_MAX];
431 	char path[PATH_MAX];
432 	const char *mnt;
433 	int n;
434 
435 	/* initialize globals */
436 	if (init_cpunode_map())
437 		return -1;
438 
439 	mnt = sysfs__mountpoint();
440 	if (!mnt)
441 		return 0;
442 
443 	n = snprintf(path, PATH_MAX, "%s/devices/system/node", mnt);
444 	if (n >= PATH_MAX) {
445 		pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
446 		return -1;
447 	}
448 
449 	dir1 = opendir(path);
450 	if (!dir1)
451 		return 0;
452 
453 	/* walk tree and setup map */
454 	while ((dent1 = readdir(dir1)) != NULL) {
455 		if (dent1->d_type != DT_DIR || sscanf(dent1->d_name, "node%u", &mem) < 1)
456 			continue;
457 
458 		n = snprintf(buf, PATH_MAX, "%s/%s", path, dent1->d_name);
459 		if (n >= PATH_MAX) {
460 			pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
461 			continue;
462 		}
463 
464 		dir2 = opendir(buf);
465 		if (!dir2)
466 			continue;
467 		while ((dent2 = readdir(dir2)) != NULL) {
468 			if (dent2->d_type != DT_LNK || sscanf(dent2->d_name, "cpu%u", &cpu) < 1)
469 				continue;
470 			cpunode_map[cpu] = mem;
471 		}
472 		closedir(dir2);
473 	}
474 	closedir(dir1);
475 	return 0;
476 }
477 
478 bool cpu_map__has(struct perf_cpu_map *cpus, int cpu)
479 {
480 	return perf_cpu_map__idx(cpus, cpu) != -1;
481 }
482 
483 int cpu_map__cpu(struct perf_cpu_map *cpus, int idx)
484 {
485 	return cpus->map[idx];
486 }
487 
488 size_t cpu_map__snprint(struct perf_cpu_map *map, char *buf, size_t size)
489 {
490 	int i, cpu, start = -1;
491 	bool first = true;
492 	size_t ret = 0;
493 
494 #define COMMA first ? "" : ","
495 
496 	for (i = 0; i < map->nr + 1; i++) {
497 		bool last = i == map->nr;
498 
499 		cpu = last ? INT_MAX : map->map[i];
500 
501 		if (start == -1) {
502 			start = i;
503 			if (last) {
504 				ret += snprintf(buf + ret, size - ret,
505 						"%s%d", COMMA,
506 						map->map[i]);
507 			}
508 		} else if (((i - start) != (cpu - map->map[start])) || last) {
509 			int end = i - 1;
510 
511 			if (start == end) {
512 				ret += snprintf(buf + ret, size - ret,
513 						"%s%d", COMMA,
514 						map->map[start]);
515 			} else {
516 				ret += snprintf(buf + ret, size - ret,
517 						"%s%d-%d", COMMA,
518 						map->map[start], map->map[end]);
519 			}
520 			first = false;
521 			start = i;
522 		}
523 	}
524 
525 #undef COMMA
526 
527 	pr_debug2("cpumask list: %s\n", buf);
528 	return ret;
529 }
530 
531 static char hex_char(unsigned char val)
532 {
533 	if (val < 10)
534 		return val + '0';
535 	if (val < 16)
536 		return val - 10 + 'a';
537 	return '?';
538 }
539 
540 size_t cpu_map__snprint_mask(struct perf_cpu_map *map, char *buf, size_t size)
541 {
542 	int i, cpu;
543 	char *ptr = buf;
544 	unsigned char *bitmap;
545 	int last_cpu = cpu_map__cpu(map, map->nr - 1);
546 
547 	if (buf == NULL)
548 		return 0;
549 
550 	bitmap = zalloc(last_cpu / 8 + 1);
551 	if (bitmap == NULL) {
552 		buf[0] = '\0';
553 		return 0;
554 	}
555 
556 	for (i = 0; i < map->nr; i++) {
557 		cpu = cpu_map__cpu(map, i);
558 		bitmap[cpu / 8] |= 1 << (cpu % 8);
559 	}
560 
561 	for (cpu = last_cpu / 4 * 4; cpu >= 0; cpu -= 4) {
562 		unsigned char bits = bitmap[cpu / 8];
563 
564 		if (cpu % 8)
565 			bits >>= 4;
566 		else
567 			bits &= 0xf;
568 
569 		*ptr++ = hex_char(bits);
570 		if ((cpu % 32) == 0 && cpu > 0)
571 			*ptr++ = ',';
572 	}
573 	*ptr = '\0';
574 	free(bitmap);
575 
576 	buf[size - 1] = '\0';
577 	return ptr - buf;
578 }
579 
580 const struct perf_cpu_map *cpu_map__online(void) /* thread unsafe */
581 {
582 	static const struct perf_cpu_map *online = NULL;
583 
584 	if (!online)
585 		online = perf_cpu_map__new(NULL); /* from /sys/devices/system/cpu/online */
586 
587 	return online;
588 }
589