root/tools/perf/util/cpumap.c

DEFINITIONS

1. cpu_map__from_entries
2. cpu_map__from_mask
3. cpu_map__new_data
4. cpu_map__fprintf
5. perf_cpu_map__empty_new
6. cpu__get_topology_int
7. cpu_map__get_socket_id
8. cpu_map__get_socket
9. cmp_ids
10. cpu_map__build_map
11. cpu_map__get_die_id
12. cpu_map__get_die
13. cpu_map__get_core_id
14. cpu_map__get_core
15. cpu_map__build_socket_map
16. cpu_map__build_die_map
17. cpu_map__build_core_map
18. get_max_num
19. set_max_cpu_num
20. set_max_node_num
21. cpu__max_node
22. cpu__max_cpu
23. cpu__max_present_cpu
24. cpu__get_node
25. init_cpunode_map
26. cpu__setup_cpunode_map
27. cpu_map__has
28. cpu_map__cpu
29. cpu_map__snprint
30. hex_char
31. cpu_map__snprint_mask
32. cpu_map__online

   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_core(struct perf_cpu_map *map, int idx, void *data)
 210 {
 211         int cpu, s_die;
 212 
 213         if (idx > map->nr)
 214                 return -1;
 215 
 216         cpu = map->map[idx];
 217 
 218         cpu = cpu_map__get_core_id(cpu);
 219 
 220         /* s_die is the combination of socket + die id */
 221         s_die = cpu_map__get_die(map, idx, data);
 222         if (s_die == -1)
 223                 return -1;
 224 
 225         /*
 226          * encode socket in bit range 31:24
 227          * encode die id in bit range 23:16
 228          * core_id is relative to socket and die,
 229          * we need a global id. So we combine
 230          * socket + die id + core id
 231          */
 232         if (WARN_ONCE(cpu >> 16, "The core id number is too big.\n"))
 233                 return -1;
 234 
 235         return (s_die << 16) | (cpu & 0xffff);
 236 }
 237 
 238 int cpu_map__build_socket_map(struct perf_cpu_map *cpus, struct perf_cpu_map **sockp)
 239 {
 240         return cpu_map__build_map(cpus, sockp, cpu_map__get_socket, NULL);
 241 }
 242 
 243 int cpu_map__build_die_map(struct perf_cpu_map *cpus, struct perf_cpu_map **diep)
 244 {
 245         return cpu_map__build_map(cpus, diep, cpu_map__get_die, NULL);
 246 }
 247 
 248 int cpu_map__build_core_map(struct perf_cpu_map *cpus, struct perf_cpu_map **corep)
 249 {
 250         return cpu_map__build_map(cpus, corep, cpu_map__get_core, NULL);
 251 }
 252 
 253 /* setup simple routines to easily access node numbers given a cpu number */
 254 static int get_max_num(char *path, int *max)
 255 {
 256         size_t num;
 257         char *buf;
 258         int err = 0;
 259 
 260         if (filename__read_str(path, &buf, &num))
 261                 return -1;
 262 
 263         buf[num] = '\0';
 264 
 265         /* start on the right, to find highest node num */
 266         while (--num) {
 267                 if ((buf[num] == ',') || (buf[num] == '-')) {
 268                         num++;
 269                         break;
 270                 }
 271         }
 272         if (sscanf(&buf[num], "%d", max) < 1) {
 273                 err = -1;
 274                 goto out;
 275         }
 276 
 277         /* convert from 0-based to 1-based */
 278         (*max)++;
 279 
 280 out:
 281         free(buf);
 282         return err;
 283 }
 284 
 285 /* Determine highest possible cpu in the system for sparse allocation */
 286 static void set_max_cpu_num(void)
 287 {
 288         const char *mnt;
 289         char path[PATH_MAX];
 290         int ret = -1;
 291 
 292         /* set up default */
 293         max_cpu_num = 4096;
 294         max_present_cpu_num = 4096;
 295 
 296         mnt = sysfs__mountpoint();
 297         if (!mnt)
 298                 goto out;
 299 
 300         /* get the highest possible cpu number for a sparse allocation */
 301         ret = snprintf(path, PATH_MAX, "%s/devices/system/cpu/possible", mnt);
 302         if (ret == PATH_MAX) {
 303                 pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
 304                 goto out;
 305         }
 306 
 307         ret = get_max_num(path, &max_cpu_num);
 308         if (ret)
 309                 goto out;
 310 
 311         /* get the highest present cpu number for a sparse allocation */
 312         ret = snprintf(path, PATH_MAX, "%s/devices/system/cpu/present", mnt);
 313         if (ret == PATH_MAX) {
 314                 pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
 315                 goto out;
 316         }
 317 
 318         ret = get_max_num(path, &max_present_cpu_num);
 319 
 320 out:
 321         if (ret)
 322                 pr_err("Failed to read max cpus, using default of %d\n", max_cpu_num);
 323 }
 324 
 325 /* Determine highest possible node in the system for sparse allocation */
 326 static void set_max_node_num(void)
 327 {
 328         const char *mnt;
 329         char path[PATH_MAX];
 330         int ret = -1;
 331 
 332         /* set up default */
 333         max_node_num = 8;
 334 
 335         mnt = sysfs__mountpoint();
 336         if (!mnt)
 337                 goto out;
 338 
 339         /* get the highest possible cpu number for a sparse allocation */
 340         ret = snprintf(path, PATH_MAX, "%s/devices/system/node/possible", mnt);
 341         if (ret == PATH_MAX) {
 342                 pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
 343                 goto out;
 344         }
 345 
 346         ret = get_max_num(path, &max_node_num);
 347 
 348 out:
 349         if (ret)
 350                 pr_err("Failed to read max nodes, using default of %d\n", max_node_num);
 351 }
 352 
 353 int cpu__max_node(void)
 354 {
 355         if (unlikely(!max_node_num))
 356                 set_max_node_num();
 357 
 358         return max_node_num;
 359 }
 360 
 361 int cpu__max_cpu(void)
 362 {
 363         if (unlikely(!max_cpu_num))
 364                 set_max_cpu_num();
 365 
 366         return max_cpu_num;
 367 }
 368 
 369 int cpu__max_present_cpu(void)
 370 {
 371         if (unlikely(!max_present_cpu_num))
 372                 set_max_cpu_num();
 373 
 374         return max_present_cpu_num;
 375 }
 376 
 377 
 378 int cpu__get_node(int cpu)
 379 {
 380         if (unlikely(cpunode_map == NULL)) {
 381                 pr_debug("cpu_map not initialized\n");
 382                 return -1;
 383         }
 384 
 385         return cpunode_map[cpu];
 386 }
 387 
 388 static int init_cpunode_map(void)
 389 {
 390         int i;
 391 
 392         set_max_cpu_num();
 393         set_max_node_num();
 394 
 395         cpunode_map = calloc(max_cpu_num, sizeof(int));
 396         if (!cpunode_map) {
 397                 pr_err("%s: calloc failed\n", __func__);
 398                 return -1;
 399         }
 400 
 401         for (i = 0; i < max_cpu_num; i++)
 402                 cpunode_map[i] = -1;
 403 
 404         return 0;
 405 }
 406 
 407 int cpu__setup_cpunode_map(void)
 408 {
 409         struct dirent *dent1, *dent2;
 410         DIR *dir1, *dir2;
 411         unsigned int cpu, mem;
 412         char buf[PATH_MAX];
 413         char path[PATH_MAX];
 414         const char *mnt;
 415         int n;
 416 
 417         /* initialize globals */
 418         if (init_cpunode_map())
 419                 return -1;
 420 
 421         mnt = sysfs__mountpoint();
 422         if (!mnt)
 423                 return 0;
 424 
 425         n = snprintf(path, PATH_MAX, "%s/devices/system/node", mnt);
 426         if (n == PATH_MAX) {
 427                 pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
 428                 return -1;
 429         }
 430 
 431         dir1 = opendir(path);
 432         if (!dir1)
 433                 return 0;
 434 
 435         /* walk tree and setup map */
 436         while ((dent1 = readdir(dir1)) != NULL) {
 437                 if (dent1->d_type != DT_DIR || sscanf(dent1->d_name, "node%u", &mem) < 1)
 438                         continue;
 439 
 440                 n = snprintf(buf, PATH_MAX, "%s/%s", path, dent1->d_name);
 441                 if (n == PATH_MAX) {
 442                         pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
 443                         continue;
 444                 }
 445 
 446                 dir2 = opendir(buf);
 447                 if (!dir2)
 448                         continue;
 449                 while ((dent2 = readdir(dir2)) != NULL) {
 450                         if (dent2->d_type != DT_LNK || sscanf(dent2->d_name, "cpu%u", &cpu) < 1)
 451                                 continue;
 452                         cpunode_map[cpu] = mem;
 453                 }
 454                 closedir(dir2);
 455         }
 456         closedir(dir1);
 457         return 0;
 458 }
 459 
 460 bool cpu_map__has(struct perf_cpu_map *cpus, int cpu)
 461 {
 462         return perf_cpu_map__idx(cpus, cpu) != -1;
 463 }
 464 
 465 int cpu_map__cpu(struct perf_cpu_map *cpus, int idx)
 466 {
 467         return cpus->map[idx];
 468 }
 469 
 470 size_t cpu_map__snprint(struct perf_cpu_map *map, char *buf, size_t size)
 471 {
 472         int i, cpu, start = -1;
 473         bool first = true;
 474         size_t ret = 0;
 475 
 476 #define COMMA first ? "" : ","
 477 
 478         for (i = 0; i < map->nr + 1; i++) {
 479                 bool last = i == map->nr;
 480 
 481                 cpu = last ? INT_MAX : map->map[i];
 482 
 483                 if (start == -1) {
 484                         start = i;
 485                         if (last) {
 486                                 ret += snprintf(buf + ret, size - ret,
 487                                                 "%s%d", COMMA,
 488                                                 map->map[i]);
 489                         }
 490                 } else if (((i - start) != (cpu - map->map[start])) || last) {
 491                         int end = i - 1;
 492 
 493                         if (start == end) {
 494                                 ret += snprintf(buf + ret, size - ret,
 495                                                 "%s%d", COMMA,
 496                                                 map->map[start]);
 497                         } else {
 498                                 ret += snprintf(buf + ret, size - ret,
 499                                                 "%s%d-%d", COMMA,
 500                                                 map->map[start], map->map[end]);
 501                         }
 502                         first = false;
 503                         start = i;
 504                 }
 505         }
 506 
 507 #undef COMMA
 508 
 509         pr_debug2("cpumask list: %s\n", buf);
 510         return ret;
 511 }
 512 
 513 static char hex_char(unsigned char val)
 514 {
 515         if (val < 10)
 516                 return val + '0';
 517         if (val < 16)
 518                 return val - 10 + 'a';
 519         return '?';
 520 }
 521 
 522 size_t cpu_map__snprint_mask(struct perf_cpu_map *map, char *buf, size_t size)
 523 {
 524         int i, cpu;
 525         char *ptr = buf;
 526         unsigned char *bitmap;
 527         int last_cpu = cpu_map__cpu(map, map->nr - 1);
 528 
 529         if (buf == NULL)
 530                 return 0;
 531 
 532         bitmap = zalloc(last_cpu / 8 + 1);
 533         if (bitmap == NULL) {
 534                 buf[0] = '\0';
 535                 return 0;
 536         }
 537 
 538         for (i = 0; i < map->nr; i++) {
 539                 cpu = cpu_map__cpu(map, i);
 540                 bitmap[cpu / 8] |= 1 << (cpu % 8);
 541         }
 542 
 543         for (cpu = last_cpu / 4 * 4; cpu >= 0; cpu -= 4) {
 544                 unsigned char bits = bitmap[cpu / 8];
 545 
 546                 if (cpu % 8)
 547                         bits >>= 4;
 548                 else
 549                         bits &= 0xf;
 550 
 551                 *ptr++ = hex_char(bits);
 552                 if ((cpu % 32) == 0 && cpu > 0)
 553                         *ptr++ = ',';
 554         }
 555         *ptr = '\0';
 556         free(bitmap);
 557 
 558         buf[size - 1] = '\0';
 559         return ptr - buf;
 560 }
 561 
 562 const struct perf_cpu_map *cpu_map__online(void) /* thread unsafe */
 563 {
 564         static const struct perf_cpu_map *online = NULL;
 565 
 566         if (!online)
 567                 online = perf_cpu_map__new(NULL); /* from /sys/devices/system/cpu/online */
 568 
 569         return online;
 570 }