xref: /openbmc/linux/tools/perf/util/cpumap.c (revision 2d96b44f)
1 #include "util.h"
2 #include <api/fs/fs.h>
3 #include "../perf.h"
4 #include "cpumap.h"
5 #include <assert.h>
6 #include <stdio.h>
7 #include <stdlib.h>
8 #include <linux/bitmap.h>
9 #include "asm/bug.h"
10 
11 static int max_cpu_num;
12 static int max_node_num;
13 static int *cpunode_map;
14 
15 static struct cpu_map *cpu_map__default_new(void)
16 {
17 	struct cpu_map *cpus;
18 	int nr_cpus;
19 
20 	nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
21 	if (nr_cpus < 0)
22 		return NULL;
23 
24 	cpus = malloc(sizeof(*cpus) + nr_cpus * sizeof(int));
25 	if (cpus != NULL) {
26 		int i;
27 		for (i = 0; i < nr_cpus; ++i)
28 			cpus->map[i] = i;
29 
30 		cpus->nr = nr_cpus;
31 		atomic_set(&cpus->refcnt, 1);
32 	}
33 
34 	return cpus;
35 }
36 
37 static struct cpu_map *cpu_map__trim_new(int nr_cpus, int *tmp_cpus)
38 {
39 	size_t payload_size = nr_cpus * sizeof(int);
40 	struct cpu_map *cpus = malloc(sizeof(*cpus) + payload_size);
41 
42 	if (cpus != NULL) {
43 		cpus->nr = nr_cpus;
44 		memcpy(cpus->map, tmp_cpus, payload_size);
45 		atomic_set(&cpus->refcnt, 1);
46 	}
47 
48 	return cpus;
49 }
50 
51 struct cpu_map *cpu_map__read(FILE *file)
52 {
53 	struct cpu_map *cpus = NULL;
54 	int nr_cpus = 0;
55 	int *tmp_cpus = NULL, *tmp;
56 	int max_entries = 0;
57 	int n, cpu, prev;
58 	char sep;
59 
60 	sep = 0;
61 	prev = -1;
62 	for (;;) {
63 		n = fscanf(file, "%u%c", &cpu, &sep);
64 		if (n <= 0)
65 			break;
66 		if (prev >= 0) {
67 			int new_max = nr_cpus + cpu - prev - 1;
68 
69 			if (new_max >= max_entries) {
70 				max_entries = new_max + MAX_NR_CPUS / 2;
71 				tmp = realloc(tmp_cpus, max_entries * sizeof(int));
72 				if (tmp == NULL)
73 					goto out_free_tmp;
74 				tmp_cpus = tmp;
75 			}
76 
77 			while (++prev < cpu)
78 				tmp_cpus[nr_cpus++] = prev;
79 		}
80 		if (nr_cpus == max_entries) {
81 			max_entries += MAX_NR_CPUS;
82 			tmp = realloc(tmp_cpus, max_entries * sizeof(int));
83 			if (tmp == NULL)
84 				goto out_free_tmp;
85 			tmp_cpus = tmp;
86 		}
87 
88 		tmp_cpus[nr_cpus++] = cpu;
89 		if (n == 2 && sep == '-')
90 			prev = cpu;
91 		else
92 			prev = -1;
93 		if (n == 1 || sep == '\n')
94 			break;
95 	}
96 
97 	if (nr_cpus > 0)
98 		cpus = cpu_map__trim_new(nr_cpus, tmp_cpus);
99 	else
100 		cpus = cpu_map__default_new();
101 out_free_tmp:
102 	free(tmp_cpus);
103 	return cpus;
104 }
105 
106 static struct cpu_map *cpu_map__read_all_cpu_map(void)
107 {
108 	struct cpu_map *cpus = NULL;
109 	FILE *onlnf;
110 
111 	onlnf = fopen("/sys/devices/system/cpu/online", "r");
112 	if (!onlnf)
113 		return cpu_map__default_new();
114 
115 	cpus = cpu_map__read(onlnf);
116 	fclose(onlnf);
117 	return cpus;
118 }
119 
120 struct cpu_map *cpu_map__new(const char *cpu_list)
121 {
122 	struct cpu_map *cpus = NULL;
123 	unsigned long start_cpu, end_cpu = 0;
124 	char *p = NULL;
125 	int i, nr_cpus = 0;
126 	int *tmp_cpus = NULL, *tmp;
127 	int max_entries = 0;
128 
129 	if (!cpu_list)
130 		return cpu_map__read_all_cpu_map();
131 
132 	if (!isdigit(*cpu_list))
133 		goto out;
134 
135 	while (isdigit(*cpu_list)) {
136 		p = NULL;
137 		start_cpu = strtoul(cpu_list, &p, 0);
138 		if (start_cpu >= INT_MAX
139 		    || (*p != '\0' && *p != ',' && *p != '-'))
140 			goto invalid;
141 
142 		if (*p == '-') {
143 			cpu_list = ++p;
144 			p = NULL;
145 			end_cpu = strtoul(cpu_list, &p, 0);
146 
147 			if (end_cpu >= INT_MAX || (*p != '\0' && *p != ','))
148 				goto invalid;
149 
150 			if (end_cpu < start_cpu)
151 				goto invalid;
152 		} else {
153 			end_cpu = start_cpu;
154 		}
155 
156 		for (; start_cpu <= end_cpu; start_cpu++) {
157 			/* check for duplicates */
158 			for (i = 0; i < nr_cpus; i++)
159 				if (tmp_cpus[i] == (int)start_cpu)
160 					goto invalid;
161 
162 			if (nr_cpus == max_entries) {
163 				max_entries += MAX_NR_CPUS;
164 				tmp = realloc(tmp_cpus, max_entries * sizeof(int));
165 				if (tmp == NULL)
166 					goto invalid;
167 				tmp_cpus = tmp;
168 			}
169 			tmp_cpus[nr_cpus++] = (int)start_cpu;
170 		}
171 		if (*p)
172 			++p;
173 
174 		cpu_list = p;
175 	}
176 
177 	if (nr_cpus > 0)
178 		cpus = cpu_map__trim_new(nr_cpus, tmp_cpus);
179 	else
180 		cpus = cpu_map__default_new();
181 invalid:
182 	free(tmp_cpus);
183 out:
184 	return cpus;
185 }
186 
187 static struct cpu_map *cpu_map__from_entries(struct cpu_map_entries *cpus)
188 {
189 	struct cpu_map *map;
190 
191 	map = cpu_map__empty_new(cpus->nr);
192 	if (map) {
193 		unsigned i;
194 
195 		for (i = 0; i < cpus->nr; i++) {
196 			/*
197 			 * Special treatment for -1, which is not real cpu number,
198 			 * and we need to use (int) -1 to initialize map[i],
199 			 * otherwise it would become 65535.
200 			 */
201 			if (cpus->cpu[i] == (u16) -1)
202 				map->map[i] = -1;
203 			else
204 				map->map[i] = (int) cpus->cpu[i];
205 		}
206 	}
207 
208 	return map;
209 }
210 
211 static struct cpu_map *cpu_map__from_mask(struct cpu_map_mask *mask)
212 {
213 	struct cpu_map *map;
214 	int nr, nbits = mask->nr * mask->long_size * BITS_PER_BYTE;
215 
216 	nr = bitmap_weight(mask->mask, nbits);
217 
218 	map = cpu_map__empty_new(nr);
219 	if (map) {
220 		int cpu, i = 0;
221 
222 		for_each_set_bit(cpu, mask->mask, nbits)
223 			map->map[i++] = cpu;
224 	}
225 	return map;
226 
227 }
228 
229 struct cpu_map *cpu_map__new_data(struct cpu_map_data *data)
230 {
231 	if (data->type == PERF_CPU_MAP__CPUS)
232 		return cpu_map__from_entries((struct cpu_map_entries *)data->data);
233 	else
234 		return cpu_map__from_mask((struct cpu_map_mask *)data->data);
235 }
236 
237 size_t cpu_map__fprintf(struct cpu_map *map, FILE *fp)
238 {
239 #define BUFSIZE 1024
240 	char buf[BUFSIZE];
241 
242 	cpu_map__snprint(map, buf, sizeof(buf));
243 	return fprintf(fp, "%s\n", buf);
244 #undef BUFSIZE
245 }
246 
247 struct cpu_map *cpu_map__dummy_new(void)
248 {
249 	struct cpu_map *cpus = malloc(sizeof(*cpus) + sizeof(int));
250 
251 	if (cpus != NULL) {
252 		cpus->nr = 1;
253 		cpus->map[0] = -1;
254 		atomic_set(&cpus->refcnt, 1);
255 	}
256 
257 	return cpus;
258 }
259 
260 struct cpu_map *cpu_map__empty_new(int nr)
261 {
262 	struct cpu_map *cpus = malloc(sizeof(*cpus) + sizeof(int) * nr);
263 
264 	if (cpus != NULL) {
265 		int i;
266 
267 		cpus->nr = nr;
268 		for (i = 0; i < nr; i++)
269 			cpus->map[i] = -1;
270 
271 		atomic_set(&cpus->refcnt, 1);
272 	}
273 
274 	return cpus;
275 }
276 
277 static void cpu_map__delete(struct cpu_map *map)
278 {
279 	if (map) {
280 		WARN_ONCE(atomic_read(&map->refcnt) != 0,
281 			  "cpu_map refcnt unbalanced\n");
282 		free(map);
283 	}
284 }
285 
286 struct cpu_map *cpu_map__get(struct cpu_map *map)
287 {
288 	if (map)
289 		atomic_inc(&map->refcnt);
290 	return map;
291 }
292 
293 void cpu_map__put(struct cpu_map *map)
294 {
295 	if (map && atomic_dec_and_test(&map->refcnt))
296 		cpu_map__delete(map);
297 }
298 
299 static int cpu__get_topology_int(int cpu, const char *name, int *value)
300 {
301 	char path[PATH_MAX];
302 
303 	snprintf(path, PATH_MAX,
304 		"devices/system/cpu/cpu%d/topology/%s", cpu, name);
305 
306 	return sysfs__read_int(path, value);
307 }
308 
309 int cpu_map__get_socket_id(int cpu)
310 {
311 	int value, ret = cpu__get_topology_int(cpu, "physical_package_id", &value);
312 	return ret ?: value;
313 }
314 
315 int cpu_map__get_socket(struct cpu_map *map, int idx, void *data __maybe_unused)
316 {
317 	int cpu;
318 
319 	if (idx > map->nr)
320 		return -1;
321 
322 	cpu = map->map[idx];
323 
324 	return cpu_map__get_socket_id(cpu);
325 }
326 
327 static int cmp_ids(const void *a, const void *b)
328 {
329 	return *(int *)a - *(int *)b;
330 }
331 
332 int cpu_map__build_map(struct cpu_map *cpus, struct cpu_map **res,
333 		       int (*f)(struct cpu_map *map, int cpu, void *data),
334 		       void *data)
335 {
336 	struct cpu_map *c;
337 	int nr = cpus->nr;
338 	int cpu, s1, s2;
339 
340 	/* allocate as much as possible */
341 	c = calloc(1, sizeof(*c) + nr * sizeof(int));
342 	if (!c)
343 		return -1;
344 
345 	for (cpu = 0; cpu < nr; cpu++) {
346 		s1 = f(cpus, cpu, data);
347 		for (s2 = 0; s2 < c->nr; s2++) {
348 			if (s1 == c->map[s2])
349 				break;
350 		}
351 		if (s2 == c->nr) {
352 			c->map[c->nr] = s1;
353 			c->nr++;
354 		}
355 	}
356 	/* ensure we process id in increasing order */
357 	qsort(c->map, c->nr, sizeof(int), cmp_ids);
358 
359 	atomic_set(&c->refcnt, 1);
360 	*res = c;
361 	return 0;
362 }
363 
364 int cpu_map__get_core_id(int cpu)
365 {
366 	int value, ret = cpu__get_topology_int(cpu, "core_id", &value);
367 	return ret ?: value;
368 }
369 
370 int cpu_map__get_core(struct cpu_map *map, int idx, void *data)
371 {
372 	int cpu, s;
373 
374 	if (idx > map->nr)
375 		return -1;
376 
377 	cpu = map->map[idx];
378 
379 	cpu = cpu_map__get_core_id(cpu);
380 
381 	s = cpu_map__get_socket(map, idx, data);
382 	if (s == -1)
383 		return -1;
384 
385 	/*
386 	 * encode socket in upper 16 bits
387 	 * core_id is relative to socket, and
388 	 * we need a global id. So we combine
389 	 * socket+ core id
390 	 */
391 	return (s << 16) | (cpu & 0xffff);
392 }
393 
394 int cpu_map__build_socket_map(struct cpu_map *cpus, struct cpu_map **sockp)
395 {
396 	return cpu_map__build_map(cpus, sockp, cpu_map__get_socket, NULL);
397 }
398 
399 int cpu_map__build_core_map(struct cpu_map *cpus, struct cpu_map **corep)
400 {
401 	return cpu_map__build_map(cpus, corep, cpu_map__get_core, NULL);
402 }
403 
404 /* setup simple routines to easily access node numbers given a cpu number */
405 static int get_max_num(char *path, int *max)
406 {
407 	size_t num;
408 	char *buf;
409 	int err = 0;
410 
411 	if (filename__read_str(path, &buf, &num))
412 		return -1;
413 
414 	buf[num] = '\0';
415 
416 	/* start on the right, to find highest node num */
417 	while (--num) {
418 		if ((buf[num] == ',') || (buf[num] == '-')) {
419 			num++;
420 			break;
421 		}
422 	}
423 	if (sscanf(&buf[num], "%d", max) < 1) {
424 		err = -1;
425 		goto out;
426 	}
427 
428 	/* convert from 0-based to 1-based */
429 	(*max)++;
430 
431 out:
432 	free(buf);
433 	return err;
434 }
435 
436 /* Determine highest possible cpu in the system for sparse allocation */
437 static void set_max_cpu_num(void)
438 {
439 	const char *mnt;
440 	char path[PATH_MAX];
441 	int ret = -1;
442 
443 	/* set up default */
444 	max_cpu_num = 4096;
445 
446 	mnt = sysfs__mountpoint();
447 	if (!mnt)
448 		goto out;
449 
450 	/* get the highest possible cpu number for a sparse allocation */
451 	ret = snprintf(path, PATH_MAX, "%s/devices/system/cpu/possible", mnt);
452 	if (ret == PATH_MAX) {
453 		pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
454 		goto out;
455 	}
456 
457 	ret = get_max_num(path, &max_cpu_num);
458 
459 out:
460 	if (ret)
461 		pr_err("Failed to read max cpus, using default of %d\n", max_cpu_num);
462 }
463 
464 /* Determine highest possible node in the system for sparse allocation */
465 static void set_max_node_num(void)
466 {
467 	const char *mnt;
468 	char path[PATH_MAX];
469 	int ret = -1;
470 
471 	/* set up default */
472 	max_node_num = 8;
473 
474 	mnt = sysfs__mountpoint();
475 	if (!mnt)
476 		goto out;
477 
478 	/* get the highest possible cpu number for a sparse allocation */
479 	ret = snprintf(path, PATH_MAX, "%s/devices/system/node/possible", mnt);
480 	if (ret == PATH_MAX) {
481 		pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
482 		goto out;
483 	}
484 
485 	ret = get_max_num(path, &max_node_num);
486 
487 out:
488 	if (ret)
489 		pr_err("Failed to read max nodes, using default of %d\n", max_node_num);
490 }
491 
492 int cpu__max_node(void)
493 {
494 	if (unlikely(!max_node_num))
495 		set_max_node_num();
496 
497 	return max_node_num;
498 }
499 
500 int cpu__max_cpu(void)
501 {
502 	if (unlikely(!max_cpu_num))
503 		set_max_cpu_num();
504 
505 	return max_cpu_num;
506 }
507 
508 int cpu__get_node(int cpu)
509 {
510 	if (unlikely(cpunode_map == NULL)) {
511 		pr_debug("cpu_map not initialized\n");
512 		return -1;
513 	}
514 
515 	return cpunode_map[cpu];
516 }
517 
518 static int init_cpunode_map(void)
519 {
520 	int i;
521 
522 	set_max_cpu_num();
523 	set_max_node_num();
524 
525 	cpunode_map = calloc(max_cpu_num, sizeof(int));
526 	if (!cpunode_map) {
527 		pr_err("%s: calloc failed\n", __func__);
528 		return -1;
529 	}
530 
531 	for (i = 0; i < max_cpu_num; i++)
532 		cpunode_map[i] = -1;
533 
534 	return 0;
535 }
536 
537 int cpu__setup_cpunode_map(void)
538 {
539 	struct dirent *dent1, *dent2;
540 	DIR *dir1, *dir2;
541 	unsigned int cpu, mem;
542 	char buf[PATH_MAX];
543 	char path[PATH_MAX];
544 	const char *mnt;
545 	int n;
546 
547 	/* initialize globals */
548 	if (init_cpunode_map())
549 		return -1;
550 
551 	mnt = sysfs__mountpoint();
552 	if (!mnt)
553 		return 0;
554 
555 	n = snprintf(path, PATH_MAX, "%s/devices/system/node", mnt);
556 	if (n == PATH_MAX) {
557 		pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
558 		return -1;
559 	}
560 
561 	dir1 = opendir(path);
562 	if (!dir1)
563 		return 0;
564 
565 	/* walk tree and setup map */
566 	while ((dent1 = readdir(dir1)) != NULL) {
567 		if (dent1->d_type != DT_DIR || sscanf(dent1->d_name, "node%u", &mem) < 1)
568 			continue;
569 
570 		n = snprintf(buf, PATH_MAX, "%s/%s", path, dent1->d_name);
571 		if (n == PATH_MAX) {
572 			pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
573 			continue;
574 		}
575 
576 		dir2 = opendir(buf);
577 		if (!dir2)
578 			continue;
579 		while ((dent2 = readdir(dir2)) != NULL) {
580 			if (dent2->d_type != DT_LNK || sscanf(dent2->d_name, "cpu%u", &cpu) < 1)
581 				continue;
582 			cpunode_map[cpu] = mem;
583 		}
584 		closedir(dir2);
585 	}
586 	closedir(dir1);
587 	return 0;
588 }
589 
590 bool cpu_map__has(struct cpu_map *cpus, int cpu)
591 {
592 	return cpu_map__idx(cpus, cpu) != -1;
593 }
594 
595 int cpu_map__idx(struct cpu_map *cpus, int cpu)
596 {
597 	int i;
598 
599 	for (i = 0; i < cpus->nr; ++i) {
600 		if (cpus->map[i] == cpu)
601 			return i;
602 	}
603 
604 	return -1;
605 }
606 
607 int cpu_map__cpu(struct cpu_map *cpus, int idx)
608 {
609 	return cpus->map[idx];
610 }
611 
612 size_t cpu_map__snprint(struct cpu_map *map, char *buf, size_t size)
613 {
614 	int i, cpu, start = -1;
615 	bool first = true;
616 	size_t ret = 0;
617 
618 #define COMMA first ? "" : ","
619 
620 	for (i = 0; i < map->nr + 1; i++) {
621 		bool last = i == map->nr;
622 
623 		cpu = last ? INT_MAX : map->map[i];
624 
625 		if (start == -1) {
626 			start = i;
627 			if (last) {
628 				ret += snprintf(buf + ret, size - ret,
629 						"%s%d", COMMA,
630 						map->map[i]);
631 			}
632 		} else if (((i - start) != (cpu - map->map[start])) || last) {
633 			int end = i - 1;
634 
635 			if (start == end) {
636 				ret += snprintf(buf + ret, size - ret,
637 						"%s%d", COMMA,
638 						map->map[start]);
639 			} else {
640 				ret += snprintf(buf + ret, size - ret,
641 						"%s%d-%d", COMMA,
642 						map->map[start], map->map[end]);
643 			}
644 			first = false;
645 			start = i;
646 		}
647 	}
648 
649 #undef COMMA
650 
651 	pr_debug("cpumask list: %s\n", buf);
652 	return ret;
653 }
654