tools/perf/util/evsel.c

   1 /*
   2  * Copyright (C) 2011, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
   3  *
   4  * Parts came from builtin-{top,stat,record}.c, see those files for further
   5  * copyright notes.
   6  *
   7  * Released under the GPL v2. (and only v2, not any later version)
   8  */
   9
  10 #include <byteswap.h>
  11 #include <linux/bitops.h>
  12 #include <lk/debugfs.h>
  13 #include <traceevent/event-parse.h>
  14 #include <linux/hw_breakpoint.h>
  15 #include <linux/perf_event.h>
  16 #include <sys/resource.h>
  17 #include "asm/bug.h"
  18 #include "evsel.h"
  19 #include "evlist.h"
  20 #include "util.h"
  21 #include "cpumap.h"
  22 #include "thread_map.h"
  23 #include "target.h"
  24 #include "perf_regs.h"
  25 #include "debug.h"
  26
  27 static struct {
  28         bool sample_id_all;
  29         bool exclude_guest;
  30 } perf_missing_features;
  31
  32 #define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
  33
  34 int __perf_evsel__sample_size(u64 sample_type)
  35 {
  36         u64 mask = sample_type & PERF_SAMPLE_MASK;
  37         int size = 0;
  38         int i;
  39
  40         for (i = 0; i < 64; i++) {
  41                 if (mask & (1ULL << i))
  42                         size++;
  43         }
  44
  45         size *= sizeof(u64);
  46
  47         return size;
  48 }
  49
  50 /**
  51  * __perf_evsel__calc_id_pos - calculate id_pos.
  52  * @sample_type: sample type
  53  *
  54  * This function returns the position of the event id (PERF_SAMPLE_ID or
  55  * PERF_SAMPLE_IDENTIFIER) in a sample event i.e. in the array of struct
  56  * sample_event.
  57  */
  58 static int __perf_evsel__calc_id_pos(u64 sample_type)
  59 {
  60         int idx = 0;
  61
  62         if (sample_type & PERF_SAMPLE_IDENTIFIER)
  63                 return 0;
  64
  65         if (!(sample_type & PERF_SAMPLE_ID))
  66                 return -1;
  67
  68         if (sample_type & PERF_SAMPLE_IP)
  69                 idx += 1;
  70
  71         if (sample_type & PERF_SAMPLE_TID)
  72                 idx += 1;
  73
  74         if (sample_type & PERF_SAMPLE_TIME)
  75                 idx += 1;
  76
  77         if (sample_type & PERF_SAMPLE_ADDR)
  78                 idx += 1;
  79
  80         return idx;
  81 }
  82
  83 /**
  84  * __perf_evsel__calc_is_pos - calculate is_pos.
  85  * @sample_type: sample type
  86  *
  87  * This function returns the position (counting backwards) of the event id
  88  * (PERF_SAMPLE_ID or PERF_SAMPLE_IDENTIFIER) in a non-sample event i.e. if
  89  * sample_id_all is used there is an id sample appended to non-sample events.
  90  */
  91 static int __perf_evsel__calc_is_pos(u64 sample_type)
  92 {
  93         int idx = 1;
  94
  95         if (sample_type & PERF_SAMPLE_IDENTIFIER)
  96                 return 1;
  97
  98         if (!(sample_type & PERF_SAMPLE_ID))
  99                 return -1;
 100
 101         if (sample_type & PERF_SAMPLE_CPU)
 102                 idx += 1;
 103
 104         if (sample_type & PERF_SAMPLE_STREAM_ID)
 105                 idx += 1;
 106
 107         return idx;
 108 }
 109
 110 void perf_evsel__calc_id_pos(struct perf_evsel *evsel)
 111 {
 112         evsel->id_pos = __perf_evsel__calc_id_pos(evsel->attr.sample_type);
 113         evsel->is_pos = __perf_evsel__calc_is_pos(evsel->attr.sample_type);
 114 }
 115
 116 void hists__init(struct hists *hists)
 117 {
 118         memset(hists, 0, sizeof(*hists));
 119         hists->entries_in_array[0] = hists->entries_in_array[1] = RB_ROOT;
 120         hists->entries_in = &hists->entries_in_array[0];
 121         hists->entries_collapsed = RB_ROOT;
 122         hists->entries = RB_ROOT;
 123         pthread_mutex_init(&hists->lock, NULL);
 124 }
 125
 126 void __perf_evsel__set_sample_bit(struct perf_evsel *evsel,
 127                                   enum perf_event_sample_format bit)
 128 {
 129         if (!(evsel->attr.sample_type & bit)) {
 130                 evsel->attr.sample_type |= bit;
 131                 evsel->sample_size += sizeof(u64);
 132                 perf_evsel__calc_id_pos(evsel);
 133         }
 134 }
 135
 136 void __perf_evsel__reset_sample_bit(struct perf_evsel *evsel,
 137                                     enum perf_event_sample_format bit)
 138 {
 139         if (evsel->attr.sample_type & bit) {
 140                 evsel->attr.sample_type &= ~bit;
 141                 evsel->sample_size -= sizeof(u64);
 142                 perf_evsel__calc_id_pos(evsel);
 143         }
 144 }
 145
 146 void perf_evsel__set_sample_id(struct perf_evsel *evsel,
 147                                bool can_sample_identifier)
 148 {
 149         if (can_sample_identifier) {
 150                 perf_evsel__reset_sample_bit(evsel, ID);
 151                 perf_evsel__set_sample_bit(evsel, IDENTIFIER);
 152         } else {
 153                 perf_evsel__set_sample_bit(evsel, ID);
 154         }
 155         evsel->attr.read_format |= PERF_FORMAT_ID;
 156 }
 157
 158 void perf_evsel__init(struct perf_evsel *evsel,
 159                       struct perf_event_attr *attr, int idx)
 160 {
 161         evsel->idx         = idx;
 162         evsel->attr        = *attr;
 163         evsel->leader      = evsel;
 164         INIT_LIST_HEAD(&evsel->node);
 165         hists__init(&evsel->hists);
 166         evsel->sample_size = __perf_evsel__sample_size(attr->sample_type);
 167         perf_evsel__calc_id_pos(evsel);
 168 }
 169
 170 struct perf_evsel *perf_evsel__new(struct perf_event_attr *attr, int idx)
 171 {
 172         struct perf_evsel *evsel = zalloc(sizeof(*evsel));
 173
 174         if (evsel != NULL)
 175                 perf_evsel__init(evsel, attr, idx);
 176
 177         return evsel;
 178 }
 179
 180 struct event_format *event_format__new(const char *sys, const char *name)
 181 {
 182         int fd, n;
 183         char *filename;
 184         void *bf = NULL, *nbf;
 185         size_t size = 0, alloc_size = 0;
 186         struct event_format *format = NULL;
 187
 188         if (asprintf(&filename, "%s/%s/%s/format", tracing_events_path, sys, name) < 0)
 189                 goto out;
 190
 191         fd = open(filename, O_RDONLY);
 192         if (fd < 0)
 193                 goto out_free_filename;
 194
 195         do {
 196                 if (size == alloc_size) {
 197                         alloc_size += BUFSIZ;
 198                         nbf = realloc(bf, alloc_size);
 199                         if (nbf == NULL)
 200                                 goto out_free_bf;
 201                         bf = nbf;
 202                 }
 203
 204                 n = read(fd, bf + size, alloc_size - size);
 205                 if (n < 0)
 206                         goto out_free_bf;
 207                 size += n;
 208         } while (n > 0);
 209
 210         pevent_parse_format(&format, bf, size, sys);
 211
 212 out_free_bf:
 213         free(bf);
 214         close(fd);
 215 out_free_filename:
 216         free(filename);
 217 out:
 218         return format;
 219 }
 220
 221 struct perf_evsel *perf_evsel__newtp(const char *sys, const char *name, int idx)
 222 {
 223         struct perf_evsel *evsel = zalloc(sizeof(*evsel));
 224
 225         if (evsel != NULL) {
 226                 struct perf_event_attr attr = {
 227                         .type          = PERF_TYPE_TRACEPOINT,
 228                         .sample_type   = (PERF_SAMPLE_RAW | PERF_SAMPLE_TIME |
 229                                           PERF_SAMPLE_CPU | PERF_SAMPLE_PERIOD),
 230                 };
 231
 232                 if (asprintf(&evsel->name, "%s:%s", sys, name) < 0)
 233                         goto out_free;
 234
 235                 evsel->tp_format = event_format__new(sys, name);
 236                 if (evsel->tp_format == NULL)
 237                         goto out_free;
 238
 239                 event_attr_init(&attr);
 240                 attr.config = evsel->tp_format->id;
 241                 attr.sample_period = 1;
 242                 perf_evsel__init(evsel, &attr, idx);
 243         }
 244
 245         return evsel;
 246
 247 out_free:
 248         free(evsel->name);
 249         free(evsel);
 250         return NULL;
 251 }
 252
 253 const char *perf_evsel__hw_names[PERF_COUNT_HW_MAX] = {
 254         "cycles",
 255         "instructions",
 256         "cache-references",
 257         "cache-misses",
 258         "branches",
 259         "branch-misses",
 260         "bus-cycles",
 261         "stalled-cycles-frontend",
 262         "stalled-cycles-backend",
 263         "ref-cycles",
 264 };
 265
 266 static const char *__perf_evsel__hw_name(u64 config)
 267 {
 268         if (config < PERF_COUNT_HW_MAX && perf_evsel__hw_names[config])
 269                 return perf_evsel__hw_names[config];
 270
 271         return "unknown-hardware";
 272 }
 273
 274 static int perf_evsel__add_modifiers(struct perf_evsel *evsel, char *bf, size_t size)
 275 {
 276         int colon = 0, r = 0;
 277         struct perf_event_attr *attr = &evsel->attr;
 278         bool exclude_guest_default = false;
 279
 280 #define MOD_PRINT(context, mod) do {                                    \
 281                 if (!attr->exclude_##context) {                         \
 282                         if (!colon) colon = ++r;                        \
 283                         r += scnprintf(bf + r, size - r, "%c", mod);    \
 284                 } } while(0)
 285
 286         if (attr->exclude_kernel || attr->exclude_user || attr->exclude_hv) {
 287                 MOD_PRINT(kernel, 'k');
 288                 MOD_PRINT(user, 'u');
 289                 MOD_PRINT(hv, 'h');
 290                 exclude_guest_default = true;
 291         }
 292
 293         if (attr->precise_ip) {
 294                 if (!colon)
 295                         colon = ++r;
 296                 r += scnprintf(bf + r, size - r, "%.*s", attr->precise_ip, "ppp");
 297                 exclude_guest_default = true;
 298         }
 299
 300         if (attr->exclude_host || attr->exclude_guest == exclude_guest_default) {
 301                 MOD_PRINT(host, 'H');
 302                 MOD_PRINT(guest, 'G');
 303         }
 304 #undef MOD_PRINT
 305         if (colon)
 306                 bf[colon - 1] = ':';
 307         return r;
 308 }
 309
 310 static int perf_evsel__hw_name(struct perf_evsel *evsel, char *bf, size_t size)
 311 {
 312         int r = scnprintf(bf, size, "%s", __perf_evsel__hw_name(evsel->attr.config));
 313         return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
 314 }
 315
 316 const char *perf_evsel__sw_names[PERF_COUNT_SW_MAX] = {
 317         "cpu-clock",
 318         "task-clock",
 319         "page-faults",
 320         "context-switches",
 321         "cpu-migrations",
 322         "minor-faults",
 323         "major-faults",
 324         "alignment-faults",
 325         "emulation-faults",
 326         "dummy",
 327 };
 328
 329 static const char *__perf_evsel__sw_name(u64 config)
 330 {
 331         if (config < PERF_COUNT_SW_MAX && perf_evsel__sw_names[config])
 332                 return perf_evsel__sw_names[config];
 333         return "unknown-software";
 334 }
 335
 336 static int perf_evsel__sw_name(struct perf_evsel *evsel, char *bf, size_t size)
 337 {
 338         int r = scnprintf(bf, size, "%s", __perf_evsel__sw_name(evsel->attr.config));
 339         return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
 340 }
 341
 342 static int __perf_evsel__bp_name(char *bf, size_t size, u64 addr, u64 type)
 343 {
 344         int r;
 345
 346         r = scnprintf(bf, size, "mem:0x%" PRIx64 ":", addr);
 347
 348         if (type & HW_BREAKPOINT_R)
 349                 r += scnprintf(bf + r, size - r, "r");
 350
 351         if (type & HW_BREAKPOINT_W)
 352                 r += scnprintf(bf + r, size - r, "w");
 353
 354         if (type & HW_BREAKPOINT_X)
 355                 r += scnprintf(bf + r, size - r, "x");
 356
 357         return r;
 358 }
 359
 360 static int perf_evsel__bp_name(struct perf_evsel *evsel, char *bf, size_t size)
 361 {
 362         struct perf_event_attr *attr = &evsel->attr;
 363         int r = __perf_evsel__bp_name(bf, size, attr->bp_addr, attr->bp_type);
 364         return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
 365 }
 366
 367 const char *perf_evsel__hw_cache[PERF_COUNT_HW_CACHE_MAX]
 368                                 [PERF_EVSEL__MAX_ALIASES] = {
 369  { "L1-dcache", "l1-d",         "l1d",          "L1-data",              },
 370  { "L1-icache", "l1-i",         "l1i",          "L1-instruction",       },
 371  { "LLC",       "L2",                                                   },
 372  { "dTLB",      "d-tlb",        "Data-TLB",                             },
 373  { "iTLB",      "i-tlb",        "Instruction-TLB",                      },
 374  { "branch",    "branches",     "bpu",          "btb",          "bpc",  },
 375  { "node",                                                              },
 376 };
 377
 378 const char *perf_evsel__hw_cache_op[PERF_COUNT_HW_CACHE_OP_MAX]
 379                                    [PERF_EVSEL__MAX_ALIASES] = {
 380  { "load",      "loads",        "read",                                 },
 381  { "store",     "stores",       "write",                                },
 382  { "prefetch",  "prefetches",   "speculative-read", "speculative-load", },
 383 };
 384
 385 const char *perf_evsel__hw_cache_result[PERF_COUNT_HW_CACHE_RESULT_MAX]
 386                                        [PERF_EVSEL__MAX_ALIASES] = {
 387  { "refs",      "Reference",    "ops",          "access",               },
 388  { "misses",    "miss",                                                 },
 389 };
 390
 391 #define C(x)            PERF_COUNT_HW_CACHE_##x
 392 #define CACHE_READ      (1 << C(OP_READ))
 393 #define CACHE_WRITE     (1 << C(OP_WRITE))
 394 #define CACHE_PREFETCH  (1 << C(OP_PREFETCH))
 395 #define COP(x)          (1 << x)
 396
 397 /*
 398  * cache operartion stat
 399  * L1I : Read and prefetch only
 400  * ITLB and BPU : Read-only
 401  */
 402 static unsigned long perf_evsel__hw_cache_stat[C(MAX)] = {
 403  [C(L1D)]       = (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 404  [C(L1I)]       = (CACHE_READ | CACHE_PREFETCH),
 405  [C(LL)]        = (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 406  [C(DTLB)]      = (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 407  [C(ITLB)]      = (CACHE_READ),
 408  [C(BPU)]       = (CACHE_READ),
 409  [C(NODE)]      = (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 410 };
 411
 412 bool perf_evsel__is_cache_op_valid(u8 type, u8 op)
 413 {
 414         if (perf_evsel__hw_cache_stat[type] & COP(op))
 415                 return true;    /* valid */
 416         else
 417                 return false;   /* invalid */
 418 }
 419
 420 int __perf_evsel__hw_cache_type_op_res_name(u8 type, u8 op, u8 result,
 421                                             char *bf, size_t size)
 422 {
 423         if (result) {
 424                 return scnprintf(bf, size, "%s-%s-%s", perf_evsel__hw_cache[type][0],
 425                                  perf_evsel__hw_cache_op[op][0],
 426                                  perf_evsel__hw_cache_result[result][0]);
 427         }
 428
 429         return scnprintf(bf, size, "%s-%s", perf_evsel__hw_cache[type][0],
 430                          perf_evsel__hw_cache_op[op][1]);
 431 }
 432
 433 static int __perf_evsel__hw_cache_name(u64 config, char *bf, size_t size)
 434 {
 435         u8 op, result, type = (config >>  0) & 0xff;
 436         const char *err = "unknown-ext-hardware-cache-type";
 437
 438         if (type > PERF_COUNT_HW_CACHE_MAX)
 439                 goto out_err;
 440
 441         op = (config >>  8) & 0xff;
 442         err = "unknown-ext-hardware-cache-op";
 443         if (op > PERF_COUNT_HW_CACHE_OP_MAX)
 444                 goto out_err;
 445
 446         result = (config >> 16) & 0xff;
 447         err = "unknown-ext-hardware-cache-result";
 448         if (result > PERF_COUNT_HW_CACHE_RESULT_MAX)
 449                 goto out_err;
 450
 451         err = "invalid-cache";
 452         if (!perf_evsel__is_cache_op_valid(type, op))
 453                 goto out_err;
 454
 455         return __perf_evsel__hw_cache_type_op_res_name(type, op, result, bf, size);
 456 out_err:
 457         return scnprintf(bf, size, "%s", err);
 458 }
 459
 460 static int perf_evsel__hw_cache_name(struct perf_evsel *evsel, char *bf, size_t size)
 461 {
 462         int ret = __perf_evsel__hw_cache_name(evsel->attr.config, bf, size);
 463         return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
 464 }
 465
 466 static int perf_evsel__raw_name(struct perf_evsel *evsel, char *bf, size_t size)
 467 {
 468         int ret = scnprintf(bf, size, "raw 0x%" PRIx64, evsel->attr.config);
 469         return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
 470 }
 471
 472 const char *perf_evsel__name(struct perf_evsel *evsel)
 473 {
 474         char bf[128];
 475
 476         if (evsel->name)
 477                 return evsel->name;
 478
 479         switch (evsel->attr.type) {
 480         case PERF_TYPE_RAW:
 481                 perf_evsel__raw_name(evsel, bf, sizeof(bf));
 482                 break;
 483
 484         case PERF_TYPE_HARDWARE:
 485                 perf_evsel__hw_name(evsel, bf, sizeof(bf));
 486                 break;
 487
 488         case PERF_TYPE_HW_CACHE:
 489                 perf_evsel__hw_cache_name(evsel, bf, sizeof(bf));
 490                 break;
 491
 492         case PERF_TYPE_SOFTWARE:
 493                 perf_evsel__sw_name(evsel, bf, sizeof(bf));
 494                 break;
 495
 496         case PERF_TYPE_TRACEPOINT:
 497                 scnprintf(bf, sizeof(bf), "%s", "unknown tracepoint");
 498                 break;
 499
 500         case PERF_TYPE_BREAKPOINT:
 501                 perf_evsel__bp_name(evsel, bf, sizeof(bf));
 502                 break;
 503
 504         default:
 505                 scnprintf(bf, sizeof(bf), "unknown attr type: %d",
 506                           evsel->attr.type);
 507                 break;
 508         }
 509
 510         evsel->name = strdup(bf);
 511
 512         return evsel->name ?: "unknown";
 513 }
 514
 515 const char *perf_evsel__group_name(struct perf_evsel *evsel)
 516 {
 517         return evsel->group_name ?: "anon group";
 518 }
 519
 520 int perf_evsel__group_desc(struct perf_evsel *evsel, char *buf, size_t size)
 521 {
 522         int ret;
 523         struct perf_evsel *pos;
 524         const char *group_name = perf_evsel__group_name(evsel);
 525
 526         ret = scnprintf(buf, size, "%s", group_name);
 527
 528         ret += scnprintf(buf + ret, size - ret, " { %s",
 529                          perf_evsel__name(evsel));
 530
 531         for_each_group_member(pos, evsel)
 532                 ret += scnprintf(buf + ret, size - ret, ", %s",
 533                                  perf_evsel__name(pos));
 534
 535         ret += scnprintf(buf + ret, size - ret, " }");
 536
 537         return ret;
 538 }
 539
 540 /*
 541  * The enable_on_exec/disabled value strategy:
 542  *
 543  *  1) For any type of traced program:
 544  *    - all independent events and group leaders are disabled
 545  *    - all group members are enabled
 546  *
 547  *     Group members are ruled by group leaders. They need to
 548  *     be enabled, because the group scheduling relies on that.
 549  *
 550  *  2) For traced programs executed by perf:
 551  *     - all independent events and group leaders have
 552  *       enable_on_exec set
 553  *     - we don't specifically enable or disable any event during
 554  *       the record command
 555  *
 556  *     Independent events and group leaders are initially disabled
 557  *     and get enabled by exec. Group members are ruled by group
 558  *     leaders as stated in 1).
 559  *
 560  *  3) For traced programs attached by perf (pid/tid):
 561  *     - we specifically enable or disable all events during
 562  *       the record command
 563  *
 564  *     When attaching events to already running traced we
 565  *     enable/disable events specifically, as there's no
 566  *     initial traced exec call.
 567  */
 568 void perf_evsel__config(struct perf_evsel *evsel,
 569                         struct perf_record_opts *opts)
 570 {
 571         struct perf_evsel *leader = evsel->leader;
 572         struct perf_event_attr *attr = &evsel->attr;
 573         int track = !evsel->idx; /* only the first counter needs these */
 574
 575         attr->sample_id_all = perf_missing_features.sample_id_all ? 0 : 1;
 576         attr->inherit       = !opts->no_inherit;
 577
 578         perf_evsel__set_sample_bit(evsel, IP);
 579         perf_evsel__set_sample_bit(evsel, TID);
 580
 581         if (evsel->sample_read) {
 582                 perf_evsel__set_sample_bit(evsel, READ);
 583
 584                 /*
 585                  * We need ID even in case of single event, because
 586                  * PERF_SAMPLE_READ process ID specific data.
 587                  */
 588                 perf_evsel__set_sample_id(evsel, false);
 589
 590                 /*
 591                  * Apply group format only if we belong to group
 592                  * with more than one members.
 593                  */
 594                 if (leader->nr_members > 1) {
 595                         attr->read_format |= PERF_FORMAT_GROUP;
 596                         attr->inherit = 0;
 597                 }
 598         }
 599
 600         /*
 601          * We default some events to a 1 default interval. But keep
 602          * it a weak assumption overridable by the user.
 603          */
 604         if (!attr->sample_period || (opts->user_freq != UINT_MAX &&
 605                                      opts->user_interval != ULLONG_MAX)) {
 606                 if (opts->freq) {
 607                         perf_evsel__set_sample_bit(evsel, PERIOD);
 608                         attr->freq              = 1;
 609                         attr->sample_freq       = opts->freq;
 610                 } else {
 611                         attr->sample_period = opts->default_interval;
 612                 }
 613         }
 614
 615         /*
 616          * Disable sampling for all group members other
 617          * than leader in case leader 'leads' the sampling.
 618          */
 619         if ((leader != evsel) && leader->sample_read) {
 620                 attr->sample_freq   = 0;
 621                 attr->sample_period = 0;
 622         }
 623
 624         if (opts->no_samples)
 625                 attr->sample_freq = 0;
 626
 627         if (opts->inherit_stat)
 628                 attr->inherit_stat = 1;
 629
 630         if (opts->sample_address) {
 631                 perf_evsel__set_sample_bit(evsel, ADDR);
 632                 attr->mmap_data = track;
 633         }
 634
 635         if (opts->call_graph) {
 636                 perf_evsel__set_sample_bit(evsel, CALLCHAIN);
 637
 638                 if (opts->call_graph == CALLCHAIN_DWARF) {
 639                         perf_evsel__set_sample_bit(evsel, REGS_USER);
 640                         perf_evsel__set_sample_bit(evsel, STACK_USER);
 641                         attr->sample_regs_user = PERF_REGS_MASK;
 642                         attr->sample_stack_user = opts->stack_dump_size;
 643                         attr->exclude_callchain_user = 1;
 644                 }
 645         }
 646
 647         if (perf_target__has_cpu(&opts->target))
 648                 perf_evsel__set_sample_bit(evsel, CPU);
 649
 650         if (opts->period)
 651                 perf_evsel__set_sample_bit(evsel, PERIOD);
 652
 653         if (!perf_missing_features.sample_id_all &&
 654             (opts->sample_time || !opts->no_inherit ||
 655              perf_target__has_cpu(&opts->target)))
 656                 perf_evsel__set_sample_bit(evsel, TIME);
 657
 658         if (opts->raw_samples) {
 659                 perf_evsel__set_sample_bit(evsel, TIME);
 660                 perf_evsel__set_sample_bit(evsel, RAW);
 661                 perf_evsel__set_sample_bit(evsel, CPU);
 662         }
 663
 664         if (opts->sample_address)
 665                 attr->sample_type       |= PERF_SAMPLE_DATA_SRC;
 666
 667         if (opts->no_delay) {
 668                 attr->watermark = 0;
 669                 attr->wakeup_events = 1;
 670         }
 671         if (opts->branch_stack) {
 672                 perf_evsel__set_sample_bit(evsel, BRANCH_STACK);
 673                 attr->branch_sample_type = opts->branch_stack;
 674         }
 675
 676         if (opts->sample_weight)
 677                 attr->sample_type       |= PERF_SAMPLE_WEIGHT;
 678
 679         attr->mmap = track;
 680         attr->comm = track;
 681
 682         /*
 683          * XXX see the function comment above
 684          *
 685          * Disabling only independent events or group leaders,
 686          * keeping group members enabled.
 687          */
 688         if (perf_evsel__is_group_leader(evsel))
 689                 attr->disabled = 1;
 690
 691         /*
 692          * Setting enable_on_exec for independent events and
 693          * group leaders for traced executed by perf.
 694          */
 695         if (perf_target__none(&opts->target) && perf_evsel__is_group_leader(evsel))
 696                 attr->enable_on_exec = 1;
 697 }
 698
 699 int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
 700 {
 701         int cpu, thread;
 702         evsel->fd = xyarray__new(ncpus, nthreads, sizeof(int));
 703
 704         if (evsel->fd) {
 705                 for (cpu = 0; cpu < ncpus; cpu++) {
 706                         for (thread = 0; thread < nthreads; thread++) {
 707                                 FD(evsel, cpu, thread) = -1;
 708                         }
 709                 }
 710         }
 711
 712         return evsel->fd != NULL ? 0 : -ENOMEM;
 713 }
 714
 715 static int perf_evsel__run_ioctl(struct perf_evsel *evsel, int ncpus, int nthreads,
 716                           int ioc,  void *arg)
 717 {
 718         int cpu, thread;
 719
 720         for (cpu = 0; cpu < ncpus; cpu++) {
 721                 for (thread = 0; thread < nthreads; thread++) {
 722                         int fd = FD(evsel, cpu, thread),
 723                             err = ioctl(fd, ioc, arg);
 724
 725                         if (err)
 726                                 return err;
 727                 }
 728         }
 729
 730         return 0;
 731 }
 732
 733 int perf_evsel__set_filter(struct perf_evsel *evsel, int ncpus, int nthreads,
 734                            const char *filter)
 735 {
 736         return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
 737                                      PERF_EVENT_IOC_SET_FILTER,
 738                                      (void *)filter);
 739 }
 740
 741 int perf_evsel__enable(struct perf_evsel *evsel, int ncpus, int nthreads)
 742 {
 743         return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
 744                                      PERF_EVENT_IOC_ENABLE,
 745                                      0);
 746 }
 747
 748 int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
 749 {
 750         evsel->sample_id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
 751         if (evsel->sample_id == NULL)
 752                 return -ENOMEM;
 753
 754         evsel->id = zalloc(ncpus * nthreads * sizeof(u64));
 755         if (evsel->id == NULL) {
 756                 xyarray__delete(evsel->sample_id);
 757                 evsel->sample_id = NULL;
 758                 return -ENOMEM;
 759         }
 760
 761         return 0;
 762 }
 763
 764 void perf_evsel__reset_counts(struct perf_evsel *evsel, int ncpus)
 765 {
 766         memset(evsel->counts, 0, (sizeof(*evsel->counts) +
 767                                  (ncpus * sizeof(struct perf_counts_values))));
 768 }
 769
 770 int perf_evsel__alloc_counts(struct perf_evsel *evsel, int ncpus)
 771 {
 772         evsel->counts = zalloc((sizeof(*evsel->counts) +
 773                                 (ncpus * sizeof(struct perf_counts_values))));
 774         return evsel->counts != NULL ? 0 : -ENOMEM;
 775 }
 776
 777 void perf_evsel__free_fd(struct perf_evsel *evsel)
 778 {
 779         xyarray__delete(evsel->fd);
 780         evsel->fd = NULL;
 781 }
 782
 783 void perf_evsel__free_id(struct perf_evsel *evsel)
 784 {
 785         xyarray__delete(evsel->sample_id);
 786         evsel->sample_id = NULL;
 787         free(evsel->id);
 788         evsel->id = NULL;
 789 }
 790
 791 void perf_evsel__close_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
 792 {
 793         int cpu, thread;
 794
 795         for (cpu = 0; cpu < ncpus; cpu++)
 796                 for (thread = 0; thread < nthreads; ++thread) {
 797                         close(FD(evsel, cpu, thread));
 798                         FD(evsel, cpu, thread) = -1;
 799                 }
 800 }
 801
 802 void perf_evsel__free_counts(struct perf_evsel *evsel)
 803 {
 804         free(evsel->counts);
 805 }
 806
 807 void perf_evsel__exit(struct perf_evsel *evsel)
 808 {
 809         assert(list_empty(&evsel->node));
 810         perf_evsel__free_fd(evsel);
 811         perf_evsel__free_id(evsel);
 812 }
 813
 814 void perf_evsel__delete(struct perf_evsel *evsel)
 815 {
 816         perf_evsel__exit(evsel);
 817         close_cgroup(evsel->cgrp);
 818         free(evsel->group_name);
 819         if (evsel->tp_format)
 820                 pevent_free_format(evsel->tp_format);
 821         free(evsel->name);
 822         free(evsel);
 823 }
 824
 825 static inline void compute_deltas(struct perf_evsel *evsel,
 826                                   int cpu,
 827                                   struct perf_counts_values *count)
 828 {
 829         struct perf_counts_values tmp;
 830
 831         if (!evsel->prev_raw_counts)
 832                 return;
 833
 834         if (cpu == -1) {
 835                 tmp = evsel->prev_raw_counts->aggr;
 836                 evsel->prev_raw_counts->aggr = *count;
 837         } else {
 838                 tmp = evsel->prev_raw_counts->cpu[cpu];
 839                 evsel->prev_raw_counts->cpu[cpu] = *count;
 840         }
 841
 842         count->val = count->val - tmp.val;
 843         count->ena = count->ena - tmp.ena;
 844         count->run = count->run - tmp.run;
 845 }
 846
 847 int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
 848                               int cpu, int thread, bool scale)
 849 {
 850         struct perf_counts_values count;
 851         size_t nv = scale ? 3 : 1;
 852
 853         if (FD(evsel, cpu, thread) < 0)
 854                 return -EINVAL;
 855
 856         if (evsel->counts == NULL && perf_evsel__alloc_counts(evsel, cpu + 1) < 0)
 857                 return -ENOMEM;
 858
 859         if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) < 0)
 860                 return -errno;
 861
 862         compute_deltas(evsel, cpu, &count);
 863
 864         if (scale) {
 865                 if (count.run == 0)
 866                         count.val = 0;
 867                 else if (count.run < count.ena)
 868                         count.val = (u64)((double)count.val * count.ena / count.run + 0.5);
 869         } else
 870                 count.ena = count.run = 0;
 871
 872         evsel->counts->cpu[cpu] = count;
 873         return 0;
 874 }
 875
 876 int __perf_evsel__read(struct perf_evsel *evsel,
 877                        int ncpus, int nthreads, bool scale)
 878 {
 879         size_t nv = scale ? 3 : 1;
 880         int cpu, thread;
 881         struct perf_counts_values *aggr = &evsel->counts->aggr, count;
 882
 883         aggr->val = aggr->ena = aggr->run = 0;
 884
 885         for (cpu = 0; cpu < ncpus; cpu++) {
 886                 for (thread = 0; thread < nthreads; thread++) {
 887                         if (FD(evsel, cpu, thread) < 0)
 888                                 continue;
 889
 890                         if (readn(FD(evsel, cpu, thread),
 891                                   &count, nv * sizeof(u64)) < 0)
 892                                 return -errno;
 893
 894                         aggr->val += count.val;
 895                         if (scale) {
 896                                 aggr->ena += count.ena;
 897                                 aggr->run += count.run;
 898                         }
 899                 }
 900         }
 901
 902         compute_deltas(evsel, -1, aggr);
 903
 904         evsel->counts->scaled = 0;
 905         if (scale) {
 906                 if (aggr->run == 0) {
 907                         evsel->counts->scaled = -1;
 908                         aggr->val = 0;
 909                         return 0;
 910                 }
 911
 912                 if (aggr->run < aggr->ena) {
 913                         evsel->counts->scaled = 1;
 914                         aggr->val = (u64)((double)aggr->val * aggr->ena / aggr->run + 0.5);
 915                 }
 916         } else
 917                 aggr->ena = aggr->run = 0;
 918
 919         return 0;
 920 }
 921
 922 static int get_group_fd(struct perf_evsel *evsel, int cpu, int thread)
 923 {
 924         struct perf_evsel *leader = evsel->leader;
 925         int fd;
 926
 927         if (perf_evsel__is_group_leader(evsel))
 928                 return -1;
 929
 930         /*
 931          * Leader must be already processed/open,
 932          * if not it's a bug.
 933          */
 934         BUG_ON(!leader->fd);
 935
 936         fd = FD(leader, cpu, thread);
 937         BUG_ON(fd == -1);
 938
 939         return fd;
 940 }
 941
 942 #define __PRINT_ATTR(fmt, cast, field)  \
 943         fprintf(fp, "  %-19s "fmt"\n", #field, cast attr->field)
 944
 945 #define PRINT_ATTR_U32(field)  __PRINT_ATTR("%u" , , field)
 946 #define PRINT_ATTR_X32(field)  __PRINT_ATTR("%#x", , field)
 947 #define PRINT_ATTR_U64(field)  __PRINT_ATTR("%" PRIu64, (uint64_t), field)
 948 #define PRINT_ATTR_X64(field)  __PRINT_ATTR("%#"PRIx64, (uint64_t), field)
 949
 950 #define PRINT_ATTR2N(name1, field1, name2, field2)      \
 951         fprintf(fp, "  %-19s %u    %-19s %u\n",         \
 952         name1, attr->field1, name2, attr->field2)
 953
 954 #define PRINT_ATTR2(field1, field2) \
 955         PRINT_ATTR2N(#field1, field1, #field2, field2)
 956
 957 static size_t perf_event_attr__fprintf(struct perf_event_attr *attr, FILE *fp)
 958 {
 959         size_t ret = 0;
 960
 961         ret += fprintf(fp, "%.60s\n", graph_dotted_line);
 962         ret += fprintf(fp, "perf_event_attr:\n");
 963
 964         ret += PRINT_ATTR_U32(type);
 965         ret += PRINT_ATTR_U32(size);
 966         ret += PRINT_ATTR_X64(config);
 967         ret += PRINT_ATTR_U64(sample_period);
 968         ret += PRINT_ATTR_U64(sample_freq);
 969         ret += PRINT_ATTR_X64(sample_type);
 970         ret += PRINT_ATTR_X64(read_format);
 971
 972         ret += PRINT_ATTR2(disabled, inherit);
 973         ret += PRINT_ATTR2(pinned, exclusive);
 974         ret += PRINT_ATTR2(exclude_user, exclude_kernel);
 975         ret += PRINT_ATTR2(exclude_hv, exclude_idle);
 976         ret += PRINT_ATTR2(mmap, comm);
 977         ret += PRINT_ATTR2(freq, inherit_stat);
 978         ret += PRINT_ATTR2(enable_on_exec, task);
 979         ret += PRINT_ATTR2(watermark, precise_ip);
 980         ret += PRINT_ATTR2(mmap_data, sample_id_all);
 981         ret += PRINT_ATTR2(exclude_host, exclude_guest);
 982         ret += PRINT_ATTR2N("excl.callchain_kern", exclude_callchain_kernel,
 983                             "excl.callchain_user", exclude_callchain_user);
 984
 985         ret += PRINT_ATTR_U32(wakeup_events);
 986         ret += PRINT_ATTR_U32(wakeup_watermark);
 987         ret += PRINT_ATTR_X32(bp_type);
 988         ret += PRINT_ATTR_X64(bp_addr);
 989         ret += PRINT_ATTR_X64(config1);
 990         ret += PRINT_ATTR_U64(bp_len);
 991         ret += PRINT_ATTR_X64(config2);
 992         ret += PRINT_ATTR_X64(branch_sample_type);
 993         ret += PRINT_ATTR_X64(sample_regs_user);
 994         ret += PRINT_ATTR_U32(sample_stack_user);
 995
 996         ret += fprintf(fp, "%.60s\n", graph_dotted_line);
 997
 998         return ret;
 999 }
1000
1001 static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1002                               struct thread_map *threads)
1003 {
1004         int cpu, thread;
1005         unsigned long flags = 0;
1006         int pid = -1, err;
1007         enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;
1008
1009         if (evsel->fd == NULL &&
1010             perf_evsel__alloc_fd(evsel, cpus->nr, threads->nr) < 0)
1011                 return -ENOMEM;
1012
1013         if (evsel->cgrp) {
1014                 flags = PERF_FLAG_PID_CGROUP;
1015                 pid = evsel->cgrp->fd;
1016         }
1017
1018 fallback_missing_features:
1019         if (perf_missing_features.exclude_guest)
1020                 evsel->attr.exclude_guest = evsel->attr.exclude_host = 0;
1021 retry_sample_id:
1022         if (perf_missing_features.sample_id_all)
1023                 evsel->attr.sample_id_all = 0;
1024
1025         if (verbose >= 2)
1026                 perf_event_attr__fprintf(&evsel->attr, stderr);
1027
1028         for (cpu = 0; cpu < cpus->nr; cpu++) {
1029
1030                 for (thread = 0; thread < threads->nr; thread++) {
1031                         int group_fd;
1032
1033                         if (!evsel->cgrp)
1034                                 pid = threads->map[thread];
1035
1036                         group_fd = get_group_fd(evsel, cpu, thread);
1037 retry_open:
1038                         pr_debug2("perf_event_open: pid %d  cpu %d  group_fd %d  flags %#lx\n",
1039                                   pid, cpus->map[cpu], group_fd, flags);
1040
1041                         FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr,
1042                                                                      pid,
1043                                                                      cpus->map[cpu],
1044                                                                      group_fd, flags);
1045                         if (FD(evsel, cpu, thread) < 0) {
1046                                 err = -errno;
1047                                 goto try_fallback;
1048                         }
1049                         set_rlimit = NO_CHANGE;
1050                 }
1051         }
1052
1053         return 0;
1054
1055 try_fallback:
1056         /*
1057          * perf stat needs between 5 and 22 fds per CPU. When we run out
1058          * of them try to increase the limits.
1059          */
1060         if (err == -EMFILE && set_rlimit < INCREASED_MAX) {
1061                 struct rlimit l;
1062                 int old_errno = errno;
1063
1064                 if (getrlimit(RLIMIT_NOFILE, &l) == 0) {
1065                         if (set_rlimit == NO_CHANGE)
1066                                 l.rlim_cur = l.rlim_max;
1067                         else {
1068                                 l.rlim_cur = l.rlim_max + 1000;
1069                                 l.rlim_max = l.rlim_cur;
1070                         }
1071                         if (setrlimit(RLIMIT_NOFILE, &l) == 0) {
1072                                 set_rlimit++;
1073                                 errno = old_errno;
1074                                 goto retry_open;
1075                         }
1076                 }
1077                 errno = old_errno;
1078         }
1079
1080         if (err != -EINVAL || cpu > 0 || thread > 0)
1081                 goto out_close;
1082
1083         if (!perf_missing_features.exclude_guest &&
1084             (evsel->attr.exclude_guest || evsel->attr.exclude_host)) {
1085                 perf_missing_features.exclude_guest = true;
1086                 goto fallback_missing_features;
1087         } else if (!perf_missing_features.sample_id_all) {
1088                 perf_missing_features.sample_id_all = true;
1089                 goto retry_sample_id;
1090         }
1091
1092 out_close:
1093         do {
1094                 while (--thread >= 0) {
1095                         close(FD(evsel, cpu, thread));
1096                         FD(evsel, cpu, thread) = -1;
1097                 }
1098                 thread = threads->nr;
1099         } while (--cpu >= 0);
1100         return err;
1101 }
1102
1103 void perf_evsel__close(struct perf_evsel *evsel, int ncpus, int nthreads)
1104 {
1105         if (evsel->fd == NULL)
1106                 return;
1107
1108         perf_evsel__close_fd(evsel, ncpus, nthreads);
1109         perf_evsel__free_fd(evsel);
1110         evsel->fd = NULL;
1111 }
1112
1113 static struct {
1114         struct cpu_map map;
1115         int cpus[1];
1116 } empty_cpu_map = {
1117         .map.nr = 1,
1118         .cpus   = { -1, },
1119 };
1120
1121 static struct {
1122         struct thread_map map;
1123         int threads[1];
1124 } empty_thread_map = {
1125         .map.nr  = 1,
1126         .threads = { -1, },
1127 };
1128
1129 int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1130                      struct thread_map *threads)
1131 {
1132         if (cpus == NULL) {
1133                 /* Work around old compiler warnings about strict aliasing */
1134                 cpus = &empty_cpu_map.map;
1135         }
1136
1137         if (threads == NULL)
1138                 threads = &empty_thread_map.map;
1139
1140         return __perf_evsel__open(evsel, cpus, threads);
1141 }
1142
1143 int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
1144                              struct cpu_map *cpus)
1145 {
1146         return __perf_evsel__open(evsel, cpus, &empty_thread_map.map);
1147 }
1148
1149 int perf_evsel__open_per_thread(struct perf_evsel *evsel,
1150                                 struct thread_map *threads)
1151 {
1152         return __perf_evsel__open(evsel, &empty_cpu_map.map, threads);
1153 }
1154
1155 static int perf_evsel__parse_id_sample(const struct perf_evsel *evsel,
1156                                        const union perf_event *event,
1157                                        struct perf_sample *sample)
1158 {
1159         u64 type = evsel->attr.sample_type;
1160         const u64 *array = event->sample.array;
1161         bool swapped = evsel->needs_swap;
1162         union u64_swap u;
1163
1164         array += ((event->header.size -
1165                    sizeof(event->header)) / sizeof(u64)) - 1;
1166
1167         if (type & PERF_SAMPLE_IDENTIFIER) {
1168                 sample->id = *array;
1169                 array--;
1170         }
1171
1172         if (type & PERF_SAMPLE_CPU) {
1173                 u.val64 = *array;
1174                 if (swapped) {
1175                         /* undo swap of u64, then swap on individual u32s */
1176                         u.val64 = bswap_64(u.val64);
1177                         u.val32[0] = bswap_32(u.val32[0]);
1178                 }
1179
1180                 sample->cpu = u.val32[0];
1181                 array--;
1182         }
1183
1184         if (type & PERF_SAMPLE_STREAM_ID) {
1185                 sample->stream_id = *array;
1186                 array--;
1187         }
1188
1189         if (type & PERF_SAMPLE_ID) {
1190                 sample->id = *array;
1191                 array--;
1192         }
1193
1194         if (type & PERF_SAMPLE_TIME) {
1195                 sample->time = *array;
1196                 array--;
1197         }
1198
1199         if (type & PERF_SAMPLE_TID) {
1200                 u.val64 = *array;
1201                 if (swapped) {
1202                         /* undo swap of u64, then swap on individual u32s */
1203                         u.val64 = bswap_64(u.val64);
1204                         u.val32[0] = bswap_32(u.val32[0]);
1205                         u.val32[1] = bswap_32(u.val32[1]);
1206                 }
1207
1208                 sample->pid = u.val32[0];
1209                 sample->tid = u.val32[1];
1210         }
1211
1212         return 0;
1213 }
1214
1215 static inline bool overflow(const void *endp, u16 max_size, const void *offset,
1216                             u64 size)
1217 {
1218         return size > max_size || offset + size > endp;
1219 }
1220
1221 #define OVERFLOW_CHECK(offset, size, max_size)                          \
1222         do {                                                            \
1223                 if (overflow(endp, (max_size), (offset), (size)))       \
1224                         return -EFAULT;                                 \
1225         } while (0)
1226
1227 #define OVERFLOW_CHECK_u64(offset) \
1228         OVERFLOW_CHECK(offset, sizeof(u64), sizeof(u64))
1229
1230 int perf_evsel__parse_sample(struct perf_evsel *evsel, union perf_event *event,
1231                              struct perf_sample *data)
1232 {
1233         u64 type = evsel->attr.sample_type;
1234         bool swapped = evsel->needs_swap;
1235         const u64 *array;
1236         u16 max_size = event->header.size;
1237         const void *endp = (void *)event + max_size;
1238         u64 sz;
1239
1240         /*
1241          * used for cross-endian analysis. See git commit 65014ab3
1242          * for why this goofiness is needed.
1243          */
1244         union u64_swap u;
1245
1246         memset(data, 0, sizeof(*data));
1247         data->cpu = data->pid = data->tid = -1;
1248         data->stream_id = data->id = data->time = -1ULL;
1249         data->period = 1;
1250         data->weight = 0;
1251
1252         if (event->header.type != PERF_RECORD_SAMPLE) {
1253                 if (!evsel->attr.sample_id_all)
1254                         return 0;
1255                 return perf_evsel__parse_id_sample(evsel, event, data);
1256         }
1257
1258         array = event->sample.array;
1259
1260         /*
1261          * The evsel's sample_size is based on PERF_SAMPLE_MASK which includes
1262          * up to PERF_SAMPLE_PERIOD.  After that overflow() must be used to
1263          * check the format does not go past the end of the event.
1264          */
1265         if (evsel->sample_size + sizeof(event->header) > event->header.size)
1266                 return -EFAULT;
1267
1268         data->id = -1ULL;
1269         if (type & PERF_SAMPLE_IDENTIFIER) {
1270                 data->id = *array;
1271                 array++;
1272         }
1273
1274         if (type & PERF_SAMPLE_IP) {
1275                 data->ip = *array;
1276                 array++;
1277         }
1278
1279         if (type & PERF_SAMPLE_TID) {
1280                 u.val64 = *array;
1281                 if (swapped) {
1282                         /* undo swap of u64, then swap on individual u32s */
1283                         u.val64 = bswap_64(u.val64);
1284                         u.val32[0] = bswap_32(u.val32[0]);
1285                         u.val32[1] = bswap_32(u.val32[1]);
1286                 }
1287
1288                 data->pid = u.val32[0];
1289                 data->tid = u.val32[1];
1290                 array++;
1291         }
1292
1293         if (type & PERF_SAMPLE_TIME) {
1294                 data->time = *array;
1295                 array++;
1296         }
1297
1298         data->addr = 0;
1299         if (type & PERF_SAMPLE_ADDR) {
1300                 data->addr = *array;
1301                 array++;
1302         }
1303
1304         if (type & PERF_SAMPLE_ID) {
1305                 data->id = *array;
1306                 array++;
1307         }
1308
1309         if (type & PERF_SAMPLE_STREAM_ID) {
1310                 data->stream_id = *array;
1311                 array++;
1312         }
1313
1314         if (type & PERF_SAMPLE_CPU) {
1315
1316                 u.val64 = *array;
1317                 if (swapped) {
1318                         /* undo swap of u64, then swap on individual u32s */
1319                         u.val64 = bswap_64(u.val64);
1320                         u.val32[0] = bswap_32(u.val32[0]);
1321                 }
1322
1323                 data->cpu = u.val32[0];
1324                 array++;
1325         }
1326
1327         if (type & PERF_SAMPLE_PERIOD) {
1328                 data->period = *array;
1329                 array++;
1330         }
1331
1332         if (type & PERF_SAMPLE_READ) {
1333                 u64 read_format = evsel->attr.read_format;
1334
1335                 OVERFLOW_CHECK_u64(array);
1336                 if (read_format & PERF_FORMAT_GROUP)
1337                         data->read.group.nr = *array;
1338                 else
1339                         data->read.one.value = *array;
1340
1341                 array++;
1342
1343                 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1344                         OVERFLOW_CHECK_u64(array);
1345                         data->read.time_enabled = *array;
1346                         array++;
1347                 }
1348
1349                 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1350                         OVERFLOW_CHECK_u64(array);
1351                         data->read.time_running = *array;
1352                         array++;
1353                 }
1354
1355                 /* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1356                 if (read_format & PERF_FORMAT_GROUP) {
1357                         const u64 max_group_nr = UINT64_MAX /
1358                                         sizeof(struct sample_read_value);
1359
1360                         if (data->read.group.nr > max_group_nr)
1361                                 return -EFAULT;
1362                         sz = data->read.group.nr *
1363                              sizeof(struct sample_read_value);
1364                         OVERFLOW_CHECK(array, sz, max_size);
1365                         data->read.group.values =
1366                                         (struct sample_read_value *)array;
1367                         array = (void *)array + sz;
1368                 } else {
1369                         OVERFLOW_CHECK_u64(array);
1370                         data->read.one.id = *array;
1371                         array++;
1372                 }
1373         }
1374
1375         if (type & PERF_SAMPLE_CALLCHAIN) {
1376                 const u64 max_callchain_nr = UINT64_MAX / sizeof(u64);
1377
1378                 OVERFLOW_CHECK_u64(array);
1379                 data->callchain = (struct ip_callchain *)array++;
1380                 if (data->callchain->nr > max_callchain_nr)
1381                         return -EFAULT;
1382                 sz = data->callchain->nr * sizeof(u64);
1383                 OVERFLOW_CHECK(array, sz, max_size);
1384                 array = (void *)array + sz;
1385         }
1386
1387         if (type & PERF_SAMPLE_RAW) {
1388                 OVERFLOW_CHECK_u64(array);
1389                 u.val64 = *array;
1390                 if (WARN_ONCE(swapped,
1391                               "Endianness of raw data not corrected!\n")) {
1392                         /* undo swap of u64, then swap on individual u32s */
1393                         u.val64 = bswap_64(u.val64);
1394                         u.val32[0] = bswap_32(u.val32[0]);
1395                         u.val32[1] = bswap_32(u.val32[1]);
1396                 }
1397                 data->raw_size = u.val32[0];
1398                 array = (void *)array + sizeof(u32);
1399
1400                 OVERFLOW_CHECK(array, data->raw_size, max_size);
1401                 data->raw_data = (void *)array;
1402                 array = (void *)array + data->raw_size;
1403         }
1404
1405         if (type & PERF_SAMPLE_BRANCH_STACK) {
1406                 const u64 max_branch_nr = UINT64_MAX /
1407                                           sizeof(struct branch_entry);
1408
1409                 OVERFLOW_CHECK_u64(array);
1410                 data->branch_stack = (struct branch_stack *)array++;
1411
1412                 if (data->branch_stack->nr > max_branch_nr)
1413                         return -EFAULT;
1414                 sz = data->branch_stack->nr * sizeof(struct branch_entry);
1415                 OVERFLOW_CHECK(array, sz, max_size);
1416                 array = (void *)array + sz;
1417         }
1418
1419         if (type & PERF_SAMPLE_REGS_USER) {
1420                 OVERFLOW_CHECK_u64(array);
1421                 data->user_regs.abi = *array;
1422                 array++;
1423
1424                 if (data->user_regs.abi) {
1425                         u64 regs_user = evsel->attr.sample_regs_user;
1426
1427                         sz = hweight_long(regs_user) * sizeof(u64);
1428                         OVERFLOW_CHECK(array, sz, max_size);
1429                         data->user_regs.regs = (u64 *)array;
1430                         array = (void *)array + sz;
1431                 }
1432         }
1433
1434         if (type & PERF_SAMPLE_STACK_USER) {
1435                 OVERFLOW_CHECK_u64(array);
1436                 sz = *array++;
1437
1438                 data->user_stack.offset = ((char *)(array - 1)
1439                                           - (char *) event);
1440
1441                 if (!sz) {
1442                         data->user_stack.size = 0;
1443                 } else {
1444                         OVERFLOW_CHECK(array, sz, max_size);
1445                         data->user_stack.data = (char *)array;
1446                         array = (void *)array + sz;
1447                         OVERFLOW_CHECK_u64(array);
1448                         data->user_stack.size = *array++;
1449                 }
1450         }
1451
1452         data->weight = 0;
1453         if (type & PERF_SAMPLE_WEIGHT) {
1454                 OVERFLOW_CHECK_u64(array);
1455                 data->weight = *array;
1456                 array++;
1457         }
1458
1459         data->data_src = PERF_MEM_DATA_SRC_NONE;
1460         if (type & PERF_SAMPLE_DATA_SRC) {
1461                 OVERFLOW_CHECK_u64(array);
1462                 data->data_src = *array;
1463                 array++;
1464         }
1465
1466         return 0;
1467 }
1468
1469 size_t perf_event__sample_event_size(const struct perf_sample *sample, u64 type,
1470                                      u64 sample_regs_user, u64 read_format)
1471 {
1472         size_t sz, result = sizeof(struct sample_event);
1473
1474         if (type & PERF_SAMPLE_IDENTIFIER)
1475                 result += sizeof(u64);
1476
1477         if (type & PERF_SAMPLE_IP)
1478                 result += sizeof(u64);
1479
1480         if (type & PERF_SAMPLE_TID)
1481                 result += sizeof(u64);
1482
1483         if (type & PERF_SAMPLE_TIME)
1484                 result += sizeof(u64);
1485
1486         if (type & PERF_SAMPLE_ADDR)
1487                 result += sizeof(u64);
1488
1489         if (type & PERF_SAMPLE_ID)
1490                 result += sizeof(u64);
1491
1492         if (type & PERF_SAMPLE_STREAM_ID)
1493                 result += sizeof(u64);
1494
1495         if (type & PERF_SAMPLE_CPU)
1496                 result += sizeof(u64);
1497
1498         if (type & PERF_SAMPLE_PERIOD)
1499                 result += sizeof(u64);
1500
1501         if (type & PERF_SAMPLE_READ) {
1502                 result += sizeof(u64);
1503                 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
1504                         result += sizeof(u64);
1505                 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
1506                         result += sizeof(u64);
1507                 /* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1508                 if (read_format & PERF_FORMAT_GROUP) {
1509                         sz = sample->read.group.nr *
1510                              sizeof(struct sample_read_value);
1511                         result += sz;
1512                 } else {
1513                         result += sizeof(u64);
1514                 }
1515         }
1516
1517         if (type & PERF_SAMPLE_CALLCHAIN) {
1518                 sz = (sample->callchain->nr + 1) * sizeof(u64);
1519                 result += sz;
1520         }
1521
1522         if (type & PERF_SAMPLE_RAW) {
1523                 result += sizeof(u32);
1524                 result += sample->raw_size;
1525         }
1526
1527         if (type & PERF_SAMPLE_BRANCH_STACK) {
1528                 sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1529                 sz += sizeof(u64);
1530                 result += sz;
1531         }
1532
1533         if (type & PERF_SAMPLE_REGS_USER) {
1534                 if (sample->user_regs.abi) {
1535                         result += sizeof(u64);
1536                         sz = hweight_long(sample_regs_user) * sizeof(u64);
1537                         result += sz;
1538                 } else {
1539                         result += sizeof(u64);
1540                 }
1541         }
1542
1543         if (type & PERF_SAMPLE_STACK_USER) {
1544                 sz = sample->user_stack.size;
1545                 result += sizeof(u64);
1546                 if (sz) {
1547                         result += sz;
1548                         result += sizeof(u64);
1549                 }
1550         }
1551
1552         if (type & PERF_SAMPLE_WEIGHT)
1553                 result += sizeof(u64);
1554
1555         if (type & PERF_SAMPLE_DATA_SRC)
1556                 result += sizeof(u64);
1557
1558         return result;
1559 }
1560
1561 int perf_event__synthesize_sample(union perf_event *event, u64 type,
1562                                   u64 sample_regs_user, u64 read_format,
1563                                   const struct perf_sample *sample,
1564                                   bool swapped)
1565 {
1566         u64 *array;
1567         size_t sz;
1568         /*
1569          * used for cross-endian analysis. See git commit 65014ab3
1570          * for why this goofiness is needed.
1571          */
1572         union u64_swap u;
1573
1574         array = event->sample.array;
1575
1576         if (type & PERF_SAMPLE_IDENTIFIER) {
1577                 *array = sample->id;
1578                 array++;
1579         }
1580
1581         if (type & PERF_SAMPLE_IP) {
1582                 *array = sample->ip;
1583                 array++;
1584         }
1585
1586         if (type & PERF_SAMPLE_TID) {
1587                 u.val32[0] = sample->pid;
1588                 u.val32[1] = sample->tid;
1589                 if (swapped) {
1590                         /*
1591                          * Inverse of what is done in perf_evsel__parse_sample
1592                          */
1593                         u.val32[0] = bswap_32(u.val32[0]);
1594                         u.val32[1] = bswap_32(u.val32[1]);
1595                         u.val64 = bswap_64(u.val64);
1596                 }
1597
1598                 *array = u.val64;
1599                 array++;
1600         }
1601
1602         if (type & PERF_SAMPLE_TIME) {
1603                 *array = sample->time;
1604                 array++;
1605         }
1606
1607         if (type & PERF_SAMPLE_ADDR) {
1608                 *array = sample->addr;
1609                 array++;
1610         }
1611
1612         if (type & PERF_SAMPLE_ID) {
1613                 *array = sample->id;
1614                 array++;
1615         }
1616
1617         if (type & PERF_SAMPLE_STREAM_ID) {
1618                 *array = sample->stream_id;
1619                 array++;
1620         }
1621
1622         if (type & PERF_SAMPLE_CPU) {
1623                 u.val32[0] = sample->cpu;
1624                 if (swapped) {
1625                         /*
1626                          * Inverse of what is done in perf_evsel__parse_sample
1627                          */
1628                         u.val32[0] = bswap_32(u.val32[0]);
1629                         u.val64 = bswap_64(u.val64);
1630                 }
1631                 *array = u.val64;
1632                 array++;
1633         }
1634
1635         if (type & PERF_SAMPLE_PERIOD) {
1636                 *array = sample->period;
1637                 array++;
1638         }
1639
1640         if (type & PERF_SAMPLE_READ) {
1641                 if (read_format & PERF_FORMAT_GROUP)
1642                         *array = sample->read.group.nr;
1643                 else
1644                         *array = sample->read.one.value;
1645                 array++;
1646
1647                 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1648                         *array = sample->read.time_enabled;
1649                         array++;
1650                 }
1651
1652                 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1653                         *array = sample->read.time_running;
1654                         array++;
1655                 }
1656
1657                 /* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1658                 if (read_format & PERF_FORMAT_GROUP) {
1659                         sz = sample->read.group.nr *
1660                              sizeof(struct sample_read_value);
1661                         memcpy(array, sample->read.group.values, sz);
1662                         array = (void *)array + sz;
1663                 } else {
1664                         *array = sample->read.one.id;
1665                         array++;
1666                 }
1667         }
1668
1669         if (type & PERF_SAMPLE_CALLCHAIN) {
1670                 sz = (sample->callchain->nr + 1) * sizeof(u64);
1671                 memcpy(array, sample->callchain, sz);
1672                 array = (void *)array + sz;
1673         }
1674
1675         if (type & PERF_SAMPLE_RAW) {
1676                 u.val32[0] = sample->raw_size;
1677                 if (WARN_ONCE(swapped,
1678                               "Endianness of raw data not corrected!\n")) {
1679                         /*
1680                          * Inverse of what is done in perf_evsel__parse_sample
1681                          */
1682                         u.val32[0] = bswap_32(u.val32[0]);
1683                         u.val32[1] = bswap_32(u.val32[1]);
1684                         u.val64 = bswap_64(u.val64);
1685                 }
1686                 *array = u.val64;
1687                 array = (void *)array + sizeof(u32);
1688
1689                 memcpy(array, sample->raw_data, sample->raw_size);
1690                 array = (void *)array + sample->raw_size;
1691         }
1692
1693         if (type & PERF_SAMPLE_BRANCH_STACK) {
1694                 sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1695                 sz += sizeof(u64);
1696                 memcpy(array, sample->branch_stack, sz);
1697                 array = (void *)array + sz;
1698         }
1699
1700         if (type & PERF_SAMPLE_REGS_USER) {
1701                 if (sample->user_regs.abi) {
1702                         *array++ = sample->user_regs.abi;
1703                         sz = hweight_long(sample_regs_user) * sizeof(u64);
1704                         memcpy(array, sample->user_regs.regs, sz);
1705                         array = (void *)array + sz;
1706                 } else {
1707                         *array++ = 0;
1708                 }
1709         }
1710
1711         if (type & PERF_SAMPLE_STACK_USER) {
1712                 sz = sample->user_stack.size;
1713                 *array++ = sz;
1714                 if (sz) {
1715                         memcpy(array, sample->user_stack.data, sz);
1716                         array = (void *)array + sz;
1717                         *array++ = sz;
1718                 }
1719         }
1720
1721         if (type & PERF_SAMPLE_WEIGHT) {
1722                 *array = sample->weight;
1723                 array++;
1724         }
1725
1726         if (type & PERF_SAMPLE_DATA_SRC) {
1727                 *array = sample->data_src;
1728                 array++;
1729         }
1730
1731         return 0;
1732 }
1733
1734 struct format_field *perf_evsel__field(struct perf_evsel *evsel, const char *name)
1735 {
1736         return pevent_find_field(evsel->tp_format, name);
1737 }
1738
1739 void *perf_evsel__rawptr(struct perf_evsel *evsel, struct perf_sample *sample,
1740                          const char *name)
1741 {
1742         struct format_field *field = perf_evsel__field(evsel, name);
1743         int offset;
1744
1745         if (!field)
1746                 return NULL;
1747
1748         offset = field->offset;
1749
1750         if (field->flags & FIELD_IS_DYNAMIC) {
1751                 offset = *(int *)(sample->raw_data + field->offset);
1752                 offset &= 0xffff;
1753         }
1754
1755         return sample->raw_data + offset;
1756 }
1757
1758 u64 perf_evsel__intval(struct perf_evsel *evsel, struct perf_sample *sample,
1759                        const char *name)
1760 {
1761         struct format_field *field = perf_evsel__field(evsel, name);
1762         void *ptr;
1763         u64 value;
1764
1765         if (!field)
1766                 return 0;
1767
1768         ptr = sample->raw_data + field->offset;
1769
1770         switch (field->size) {
1771         case 1:
1772                 return *(u8 *)ptr;
1773         case 2:
1774                 value = *(u16 *)ptr;
1775                 break;
1776         case 4:
1777                 value = *(u32 *)ptr;
1778                 break;
1779         case 8:
1780                 value = *(u64 *)ptr;
1781                 break;
1782         default:
1783                 return 0;
1784         }
1785
1786         if (!evsel->needs_swap)
1787                 return value;
1788
1789         switch (field->size) {
1790         case 2:
1791                 return bswap_16(value);
1792         case 4:
1793                 return bswap_32(value);
1794         case 8:
1795                 return bswap_64(value);
1796         default:
1797                 return 0;
1798         }
1799
1800         return 0;
1801 }
1802
1803 static int comma_fprintf(FILE *fp, bool *first, const char *fmt, ...)
1804 {
1805         va_list args;
1806         int ret = 0;
1807
1808         if (!*first) {
1809                 ret += fprintf(fp, ",");
1810         } else {
1811                 ret += fprintf(fp, ":");
1812                 *first = false;
1813         }
1814
1815         va_start(args, fmt);
1816         ret += vfprintf(fp, fmt, args);
1817         va_end(args);
1818         return ret;
1819 }
1820
1821 static int __if_fprintf(FILE *fp, bool *first, const char *field, u64 value)
1822 {
1823         if (value == 0)
1824                 return 0;
1825
1826         return comma_fprintf(fp, first, " %s: %" PRIu64, field, value);
1827 }
1828
1829 #define if_print(field) printed += __if_fprintf(fp, &first, #field, evsel->attr.field)
1830
1831 struct bit_names {
1832         int bit;
1833         const char *name;
1834 };
1835
1836 static int bits__fprintf(FILE *fp, const char *field, u64 value,
1837                          struct bit_names *bits, bool *first)
1838 {
1839         int i = 0, printed = comma_fprintf(fp, first, " %s: ", field);
1840         bool first_bit = true;
1841
1842         do {
1843                 if (value & bits[i].bit) {
1844                         printed += fprintf(fp, "%s%s", first_bit ? "" : "|", bits[i].name);
1845                         first_bit = false;
1846                 }
1847         } while (bits[++i].name != NULL);
1848
1849         return printed;
1850 }
1851
1852 static int sample_type__fprintf(FILE *fp, bool *first, u64 value)
1853 {
1854 #define bit_name(n) { PERF_SAMPLE_##n, #n }
1855         struct bit_names bits[] = {
1856                 bit_name(IP), bit_name(TID), bit_name(TIME), bit_name(ADDR),
1857                 bit_name(READ), bit_name(CALLCHAIN), bit_name(ID), bit_name(CPU),
1858                 bit_name(PERIOD), bit_name(STREAM_ID), bit_name(RAW),
1859                 bit_name(BRANCH_STACK), bit_name(REGS_USER), bit_name(STACK_USER),
1860                 bit_name(IDENTIFIER),
1861                 { .name = NULL, }
1862         };
1863 #undef bit_name
1864         return bits__fprintf(fp, "sample_type", value, bits, first);
1865 }
1866
1867 static int read_format__fprintf(FILE *fp, bool *first, u64 value)
1868 {
1869 #define bit_name(n) { PERF_FORMAT_##n, #n }
1870         struct bit_names bits[] = {
1871                 bit_name(TOTAL_TIME_ENABLED), bit_name(TOTAL_TIME_RUNNING),
1872                 bit_name(ID), bit_name(GROUP),
1873                 { .name = NULL, }
1874         };
1875 #undef bit_name
1876         return bits__fprintf(fp, "read_format", value, bits, first);
1877 }
1878
1879 int perf_evsel__fprintf(struct perf_evsel *evsel,
1880                         struct perf_attr_details *details, FILE *fp)
1881 {
1882         bool first = true;
1883         int printed = 0;
1884
1885         if (details->event_group) {
1886                 struct perf_evsel *pos;
1887
1888                 if (!perf_evsel__is_group_leader(evsel))
1889                         return 0;
1890
1891                 if (evsel->nr_members > 1)
1892                         printed += fprintf(fp, "%s{", evsel->group_name ?: "");
1893
1894                 printed += fprintf(fp, "%s", perf_evsel__name(evsel));
1895                 for_each_group_member(pos, evsel)
1896                         printed += fprintf(fp, ",%s", perf_evsel__name(pos));
1897
1898                 if (evsel->nr_members > 1)
1899                         printed += fprintf(fp, "}");
1900                 goto out;
1901         }
1902
1903         printed += fprintf(fp, "%s", perf_evsel__name(evsel));
1904
1905         if (details->verbose || details->freq) {
1906                 printed += comma_fprintf(fp, &first, " sample_freq=%" PRIu64,
1907                                          (u64)evsel->attr.sample_freq);
1908         }
1909
1910         if (details->verbose) {
1911                 if_print(type);
1912                 if_print(config);
1913                 if_print(config1);
1914                 if_print(config2);
1915                 if_print(size);
1916                 printed += sample_type__fprintf(fp, &first, evsel->attr.sample_type);
1917                 if (evsel->attr.read_format)
1918                         printed += read_format__fprintf(fp, &first, evsel->attr.read_format);
1919                 if_print(disabled);
1920                 if_print(inherit);
1921                 if_print(pinned);
1922                 if_print(exclusive);
1923                 if_print(exclude_user);
1924                 if_print(exclude_kernel);
1925                 if_print(exclude_hv);
1926                 if_print(exclude_idle);
1927                 if_print(mmap);
1928                 if_print(comm);
1929                 if_print(freq);
1930                 if_print(inherit_stat);
1931                 if_print(enable_on_exec);
1932                 if_print(task);
1933                 if_print(watermark);
1934                 if_print(precise_ip);
1935                 if_print(mmap_data);
1936                 if_print(sample_id_all);
1937                 if_print(exclude_host);
1938                 if_print(exclude_guest);
1939                 if_print(__reserved_1);
1940                 if_print(wakeup_events);
1941                 if_print(bp_type);
1942                 if_print(branch_sample_type);
1943         }
1944 out:
1945         fputc('\n', fp);
1946         return ++printed;
1947 }
1948
1949 bool perf_evsel__fallback(struct perf_evsel *evsel, int err,
1950                           char *msg, size_t msgsize)
1951 {
1952         if ((err == ENOENT || err == ENXIO || err == ENODEV) &&
1953             evsel->attr.type   == PERF_TYPE_HARDWARE &&
1954             evsel->attr.config == PERF_COUNT_HW_CPU_CYCLES) {
1955                 /*
1956                  * If it's cycles then fall back to hrtimer based
1957                  * cpu-clock-tick sw counter, which is always available even if
1958                  * no PMU support.
1959                  *
1960                  * PPC returns ENXIO until 2.6.37 (behavior changed with commit
1961                  * b0a873e).
1962                  */
1963                 scnprintf(msg, msgsize, "%s",
1964 "The cycles event is not supported, trying to fall back to cpu-clock-ticks");
1965
1966                 evsel->attr.type   = PERF_TYPE_SOFTWARE;
1967                 evsel->attr.config = PERF_COUNT_SW_CPU_CLOCK;
1968
1969                 free(evsel->name);
1970                 evsel->name = NULL;
1971                 return true;
1972         }
1973
1974         return false;
1975 }
1976
1977 int perf_evsel__open_strerror(struct perf_evsel *evsel,
1978                               struct perf_target *target,
1979                               int err, char *msg, size_t size)
1980 {
1981         switch (err) {
1982         case EPERM:
1983         case EACCES:
1984                 return scnprintf(msg, size,
1985                  "You may not have permission to collect %sstats.\n"
1986                  "Consider tweaking /proc/sys/kernel/perf_event_paranoid:\n"
1987                  " -1 - Not paranoid at all\n"
1988                  "  0 - Disallow raw tracepoint access for unpriv\n"
1989                  "  1 - Disallow cpu events for unpriv\n"
1990                  "  2 - Disallow kernel profiling for unpriv",
1991                                  target->system_wide ? "system-wide " : "");
1992         case ENOENT:
1993                 return scnprintf(msg, size, "The %s event is not supported.",
1994                                  perf_evsel__name(evsel));
1995         case EMFILE:
1996                 return scnprintf(msg, size, "%s",
1997                          "Too many events are opened.\n"
1998                          "Try again after reducing the number of events.");
1999         case ENODEV:
2000                 if (target->cpu_list)
2001                         return scnprintf(msg, size, "%s",
2002          "No such device - did you specify an out-of-range profile CPU?\n");
2003                 break;
2004         case EOPNOTSUPP:
2005                 if (evsel->attr.precise_ip)
2006                         return scnprintf(msg, size, "%s",
2007         "\'precise\' request may not be supported. Try removing 'p' modifier.");
2008 #if defined(__i386__) || defined(__x86_64__)
2009                 if (evsel->attr.type == PERF_TYPE_HARDWARE)
2010                         return scnprintf(msg, size, "%s",
2011         "No hardware sampling interrupt available.\n"
2012         "No APIC? If so then you can boot the kernel with the \"lapic\" boot parameter to force-enable it.");
2013 #endif
2014                 break;
2015         default:
2016                 break;
2017         }
2018
2019         return scnprintf(msg, size,
2020         "The sys_perf_event_open() syscall returned with %d (%s) for event (%s).  \n"
2021         "/bin/dmesg may provide additional information.\n"
2022         "No CONFIG_PERF_EVENTS=y kernel support configured?\n",
2023                          err, strerror(err), perf_evsel__name(evsel));
2024 }