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         bool mmap2;
  31 } perf_missing_features;
  32
  33 #define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
  34
  35 int __perf_evsel__sample_size(u64 sample_type)
  36 {
  37         u64 mask = sample_type & PERF_SAMPLE_MASK;
  38         int size = 0;
  39         int i;
  40
  41         for (i = 0; i < 64; i++) {
  42                 if (mask & (1ULL << i))
  43                         size++;
  44         }
  45
  46         size *= sizeof(u64);
  47
  48         return size;
  49 }
  50
  51 /**
  52  * __perf_evsel__calc_id_pos - calculate id_pos.
  53  * @sample_type: sample type
  54  *
  55  * This function returns the position of the event id (PERF_SAMPLE_ID or
  56  * PERF_SAMPLE_IDENTIFIER) in a sample event i.e. in the array of struct
  57  * sample_event.
  58  */
  59 static int __perf_evsel__calc_id_pos(u64 sample_type)
  60 {
  61         int idx = 0;
  62
  63         if (sample_type & PERF_SAMPLE_IDENTIFIER)
  64                 return 0;
  65
  66         if (!(sample_type & PERF_SAMPLE_ID))
  67                 return -1;
  68
  69         if (sample_type & PERF_SAMPLE_IP)
  70                 idx += 1;
  71
  72         if (sample_type & PERF_SAMPLE_TID)
  73                 idx += 1;
  74
  75         if (sample_type & PERF_SAMPLE_TIME)
  76                 idx += 1;
  77
  78         if (sample_type & PERF_SAMPLE_ADDR)
  79                 idx += 1;
  80
  81         return idx;
  82 }
  83
  84 /**
  85  * __perf_evsel__calc_is_pos - calculate is_pos.
  86  * @sample_type: sample type
  87  *
  88  * This function returns the position (counting backwards) of the event id
  89  * (PERF_SAMPLE_ID or PERF_SAMPLE_IDENTIFIER) in a non-sample event i.e. if
  90  * sample_id_all is used there is an id sample appended to non-sample events.
  91  */
  92 static int __perf_evsel__calc_is_pos(u64 sample_type)
  93 {
  94         int idx = 1;
  95
  96         if (sample_type & PERF_SAMPLE_IDENTIFIER)
  97                 return 1;
  98
  99         if (!(sample_type & PERF_SAMPLE_ID))
 100                 return -1;
 101
 102         if (sample_type & PERF_SAMPLE_CPU)
 103                 idx += 1;
 104
 105         if (sample_type & PERF_SAMPLE_STREAM_ID)
 106                 idx += 1;
 107
 108         return idx;
 109 }
 110
 111 void perf_evsel__calc_id_pos(struct perf_evsel *evsel)
 112 {
 113         evsel->id_pos = __perf_evsel__calc_id_pos(evsel->attr.sample_type);
 114         evsel->is_pos = __perf_evsel__calc_is_pos(evsel->attr.sample_type);
 115 }
 116
 117 void hists__init(struct hists *hists)
 118 {
 119         memset(hists, 0, sizeof(*hists));
 120         hists->entries_in_array[0] = hists->entries_in_array[1] = RB_ROOT;
 121         hists->entries_in = &hists->entries_in_array[0];
 122         hists->entries_collapsed = RB_ROOT;
 123         hists->entries = RB_ROOT;
 124         pthread_mutex_init(&hists->lock, NULL);
 125 }
 126
 127 void __perf_evsel__set_sample_bit(struct perf_evsel *evsel,
 128                                   enum perf_event_sample_format bit)
 129 {
 130         if (!(evsel->attr.sample_type & bit)) {
 131                 evsel->attr.sample_type |= bit;
 132                 evsel->sample_size += sizeof(u64);
 133                 perf_evsel__calc_id_pos(evsel);
 134         }
 135 }
 136
 137 void __perf_evsel__reset_sample_bit(struct perf_evsel *evsel,
 138                                     enum perf_event_sample_format bit)
 139 {
 140         if (evsel->attr.sample_type & bit) {
 141                 evsel->attr.sample_type &= ~bit;
 142                 evsel->sample_size -= sizeof(u64);
 143                 perf_evsel__calc_id_pos(evsel);
 144         }
 145 }
 146
 147 void perf_evsel__set_sample_id(struct perf_evsel *evsel,
 148                                bool can_sample_identifier)
 149 {
 150         if (can_sample_identifier) {
 151                 perf_evsel__reset_sample_bit(evsel, ID);
 152                 perf_evsel__set_sample_bit(evsel, IDENTIFIER);
 153         } else {
 154                 perf_evsel__set_sample_bit(evsel, ID);
 155         }
 156         evsel->attr.read_format |= PERF_FORMAT_ID;
 157 }
 158
 159 void perf_evsel__init(struct perf_evsel *evsel,
 160                       struct perf_event_attr *attr, int idx)
 161 {
 162         evsel->idx         = idx;
 163         evsel->attr        = *attr;
 164         evsel->leader      = evsel;
 165         INIT_LIST_HEAD(&evsel->node);
 166         hists__init(&evsel->hists);
 167         evsel->sample_size = __perf_evsel__sample_size(attr->sample_type);
 168         perf_evsel__calc_id_pos(evsel);
 169 }
 170
 171 struct perf_evsel *perf_evsel__new(struct perf_event_attr *attr, int idx)
 172 {
 173         struct perf_evsel *evsel = zalloc(sizeof(*evsel));
 174
 175         if (evsel != NULL)
 176                 perf_evsel__init(evsel, attr, idx);
 177
 178         return evsel;
 179 }
 180
 181 struct event_format *event_format__new(const char *sys, const char *name)
 182 {
 183         int fd, n;
 184         char *filename;
 185         void *bf = NULL, *nbf;
 186         size_t size = 0, alloc_size = 0;
 187         struct event_format *format = NULL;
 188
 189         if (asprintf(&filename, "%s/%s/%s/format", tracing_events_path, sys, name) < 0)
 190                 goto out;
 191
 192         fd = open(filename, O_RDONLY);
 193         if (fd < 0)
 194                 goto out_free_filename;
 195
 196         do {
 197                 if (size == alloc_size) {
 198                         alloc_size += BUFSIZ;
 199                         nbf = realloc(bf, alloc_size);
 200                         if (nbf == NULL)
 201                                 goto out_free_bf;
 202                         bf = nbf;
 203                 }
 204
 205                 n = read(fd, bf + size, alloc_size - size);
 206                 if (n < 0)
 207                         goto out_free_bf;
 208                 size += n;
 209         } while (n > 0);
 210
 211         pevent_parse_format(&format, bf, size, sys);
 212
 213 out_free_bf:
 214         free(bf);
 215         close(fd);
 216 out_free_filename:
 217         free(filename);
 218 out:
 219         return format;
 220 }
 221
 222 struct perf_evsel *perf_evsel__newtp(const char *sys, const char *name, int idx)
 223 {
 224         struct perf_evsel *evsel = zalloc(sizeof(*evsel));
 225
 226         if (evsel != NULL) {
 227                 struct perf_event_attr attr = {
 228                         .type          = PERF_TYPE_TRACEPOINT,
 229                         .sample_type   = (PERF_SAMPLE_RAW | PERF_SAMPLE_TIME |
 230                                           PERF_SAMPLE_CPU | PERF_SAMPLE_PERIOD),
 231                 };
 232
 233                 if (asprintf(&evsel->name, "%s:%s", sys, name) < 0)
 234                         goto out_free;
 235
 236                 evsel->tp_format = event_format__new(sys, name);
 237                 if (evsel->tp_format == NULL)
 238                         goto out_free;
 239
 240                 event_attr_init(&attr);
 241                 attr.config = evsel->tp_format->id;
 242                 attr.sample_period = 1;
 243                 perf_evsel__init(evsel, &attr, idx);
 244         }
 245
 246         return evsel;
 247
 248 out_free:
 249         free(evsel->name);
 250         free(evsel);
 251         return NULL;
 252 }
 253
 254 const char *perf_evsel__hw_names[PERF_COUNT_HW_MAX] = {
 255         "cycles",
 256         "instructions",
 257         "cache-references",
 258         "cache-misses",
 259         "branches",
 260         "branch-misses",
 261         "bus-cycles",
 262         "stalled-cycles-frontend",
 263         "stalled-cycles-backend",
 264         "ref-cycles",
 265 };
 266
 267 static const char *__perf_evsel__hw_name(u64 config)
 268 {
 269         if (config < PERF_COUNT_HW_MAX && perf_evsel__hw_names[config])
 270                 return perf_evsel__hw_names[config];
 271
 272         return "unknown-hardware";
 273 }
 274
 275 static int perf_evsel__add_modifiers(struct perf_evsel *evsel, char *bf, size_t size)
 276 {
 277         int colon = 0, r = 0;
 278         struct perf_event_attr *attr = &evsel->attr;
 279         bool exclude_guest_default = false;
 280
 281 #define MOD_PRINT(context, mod) do {                                    \
 282                 if (!attr->exclude_##context) {                         \
 283                         if (!colon) colon = ++r;                        \
 284                         r += scnprintf(bf + r, size - r, "%c", mod);    \
 285                 } } while(0)
 286
 287         if (attr->exclude_kernel || attr->exclude_user || attr->exclude_hv) {
 288                 MOD_PRINT(kernel, 'k');
 289                 MOD_PRINT(user, 'u');
 290                 MOD_PRINT(hv, 'h');
 291                 exclude_guest_default = true;
 292         }
 293
 294         if (attr->precise_ip) {
 295                 if (!colon)
 296                         colon = ++r;
 297                 r += scnprintf(bf + r, size - r, "%.*s", attr->precise_ip, "ppp");
 298                 exclude_guest_default = true;
 299         }
 300
 301         if (attr->exclude_host || attr->exclude_guest == exclude_guest_default) {
 302                 MOD_PRINT(host, 'H');
 303                 MOD_PRINT(guest, 'G');
 304         }
 305 #undef MOD_PRINT
 306         if (colon)
 307                 bf[colon - 1] = ':';
 308         return r;
 309 }
 310
 311 static int perf_evsel__hw_name(struct perf_evsel *evsel, char *bf, size_t size)
 312 {
 313         int r = scnprintf(bf, size, "%s", __perf_evsel__hw_name(evsel->attr.config));
 314         return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
 315 }
 316
 317 const char *perf_evsel__sw_names[PERF_COUNT_SW_MAX] = {
 318         "cpu-clock",
 319         "task-clock",
 320         "page-faults",
 321         "context-switches",
 322         "cpu-migrations",
 323         "minor-faults",
 324         "major-faults",
 325         "alignment-faults",
 326         "emulation-faults",
 327         "dummy",
 328 };
 329
 330 static const char *__perf_evsel__sw_name(u64 config)
 331 {
 332         if (config < PERF_COUNT_SW_MAX && perf_evsel__sw_names[config])
 333                 return perf_evsel__sw_names[config];
 334         return "unknown-software";
 335 }
 336
 337 static int perf_evsel__sw_name(struct perf_evsel *evsel, char *bf, size_t size)
 338 {
 339         int r = scnprintf(bf, size, "%s", __perf_evsel__sw_name(evsel->attr.config));
 340         return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
 341 }
 342
 343 static int __perf_evsel__bp_name(char *bf, size_t size, u64 addr, u64 type)
 344 {
 345         int r;
 346
 347         r = scnprintf(bf, size, "mem:0x%" PRIx64 ":", addr);
 348
 349         if (type & HW_BREAKPOINT_R)
 350                 r += scnprintf(bf + r, size - r, "r");
 351
 352         if (type & HW_BREAKPOINT_W)
 353                 r += scnprintf(bf + r, size - r, "w");
 354
 355         if (type & HW_BREAKPOINT_X)
 356                 r += scnprintf(bf + r, size - r, "x");
 357
 358         return r;
 359 }
 360
 361 static int perf_evsel__bp_name(struct perf_evsel *evsel, char *bf, size_t size)
 362 {
 363         struct perf_event_attr *attr = &evsel->attr;
 364         int r = __perf_evsel__bp_name(bf, size, attr->bp_addr, attr->bp_type);
 365         return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
 366 }
 367
 368 const char *perf_evsel__hw_cache[PERF_COUNT_HW_CACHE_MAX]
 369                                 [PERF_EVSEL__MAX_ALIASES] = {
 370  { "L1-dcache", "l1-d",         "l1d",          "L1-data",              },
 371  { "L1-icache", "l1-i",         "l1i",          "L1-instruction",       },
 372  { "LLC",       "L2",                                                   },
 373  { "dTLB",      "d-tlb",        "Data-TLB",                             },
 374  { "iTLB",      "i-tlb",        "Instruction-TLB",                      },
 375  { "branch",    "branches",     "bpu",          "btb",          "bpc",  },
 376  { "node",                                                              },
 377 };
 378
 379 const char *perf_evsel__hw_cache_op[PERF_COUNT_HW_CACHE_OP_MAX]
 380                                    [PERF_EVSEL__MAX_ALIASES] = {
 381  { "load",      "loads",        "read",                                 },
 382  { "store",     "stores",       "write",                                },
 383  { "prefetch",  "prefetches",   "speculative-read", "speculative-load", },
 384 };
 385
 386 const char *perf_evsel__hw_cache_result[PERF_COUNT_HW_CACHE_RESULT_MAX]
 387                                        [PERF_EVSEL__MAX_ALIASES] = {
 388  { "refs",      "Reference",    "ops",          "access",               },
 389  { "misses",    "miss",                                                 },
 390 };
 391
 392 #define C(x)            PERF_COUNT_HW_CACHE_##x
 393 #define CACHE_READ      (1 << C(OP_READ))
 394 #define CACHE_WRITE     (1 << C(OP_WRITE))
 395 #define CACHE_PREFETCH  (1 << C(OP_PREFETCH))
 396 #define COP(x)          (1 << x)
 397
 398 /*
 399  * cache operartion stat
 400  * L1I : Read and prefetch only
 401  * ITLB and BPU : Read-only
 402  */
 403 static unsigned long perf_evsel__hw_cache_stat[C(MAX)] = {
 404  [C(L1D)]       = (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 405  [C(L1I)]       = (CACHE_READ | CACHE_PREFETCH),
 406  [C(LL)]        = (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 407  [C(DTLB)]      = (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 408  [C(ITLB)]      = (CACHE_READ),
 409  [C(BPU)]       = (CACHE_READ),
 410  [C(NODE)]      = (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 411 };
 412
 413 bool perf_evsel__is_cache_op_valid(u8 type, u8 op)
 414 {
 415         if (perf_evsel__hw_cache_stat[type] & COP(op))
 416                 return true;    /* valid */
 417         else
 418                 return false;   /* invalid */
 419 }
 420
 421 int __perf_evsel__hw_cache_type_op_res_name(u8 type, u8 op, u8 result,
 422                                             char *bf, size_t size)
 423 {
 424         if (result) {
 425                 return scnprintf(bf, size, "%s-%s-%s", perf_evsel__hw_cache[type][0],
 426                                  perf_evsel__hw_cache_op[op][0],
 427                                  perf_evsel__hw_cache_result[result][0]);
 428         }
 429
 430         return scnprintf(bf, size, "%s-%s", perf_evsel__hw_cache[type][0],
 431                          perf_evsel__hw_cache_op[op][1]);
 432 }
 433
 434 static int __perf_evsel__hw_cache_name(u64 config, char *bf, size_t size)
 435 {
 436         u8 op, result, type = (config >>  0) & 0xff;
 437         const char *err = "unknown-ext-hardware-cache-type";
 438
 439         if (type > PERF_COUNT_HW_CACHE_MAX)
 440                 goto out_err;
 441
 442         op = (config >>  8) & 0xff;
 443         err = "unknown-ext-hardware-cache-op";
 444         if (op > PERF_COUNT_HW_CACHE_OP_MAX)
 445                 goto out_err;
 446
 447         result = (config >> 16) & 0xff;
 448         err = "unknown-ext-hardware-cache-result";
 449         if (result > PERF_COUNT_HW_CACHE_RESULT_MAX)
 450                 goto out_err;
 451
 452         err = "invalid-cache";
 453         if (!perf_evsel__is_cache_op_valid(type, op))
 454                 goto out_err;
 455
 456         return __perf_evsel__hw_cache_type_op_res_name(type, op, result, bf, size);
 457 out_err:
 458         return scnprintf(bf, size, "%s", err);
 459 }
 460
 461 static int perf_evsel__hw_cache_name(struct perf_evsel *evsel, char *bf, size_t size)
 462 {
 463         int ret = __perf_evsel__hw_cache_name(evsel->attr.config, bf, size);
 464         return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
 465 }
 466
 467 static int perf_evsel__raw_name(struct perf_evsel *evsel, char *bf, size_t size)
 468 {
 469         int ret = scnprintf(bf, size, "raw 0x%" PRIx64, evsel->attr.config);
 470         return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
 471 }
 472
 473 const char *perf_evsel__name(struct perf_evsel *evsel)
 474 {
 475         char bf[128];
 476
 477         if (evsel->name)
 478                 return evsel->name;
 479
 480         switch (evsel->attr.type) {
 481         case PERF_TYPE_RAW:
 482                 perf_evsel__raw_name(evsel, bf, sizeof(bf));
 483                 break;
 484
 485         case PERF_TYPE_HARDWARE:
 486                 perf_evsel__hw_name(evsel, bf, sizeof(bf));
 487                 break;
 488
 489         case PERF_TYPE_HW_CACHE:
 490                 perf_evsel__hw_cache_name(evsel, bf, sizeof(bf));
 491                 break;
 492
 493         case PERF_TYPE_SOFTWARE:
 494                 perf_evsel__sw_name(evsel, bf, sizeof(bf));
 495                 break;
 496
 497         case PERF_TYPE_TRACEPOINT:
 498                 scnprintf(bf, sizeof(bf), "%s", "unknown tracepoint");
 499                 break;
 500
 501         case PERF_TYPE_BREAKPOINT:
 502                 perf_evsel__bp_name(evsel, bf, sizeof(bf));
 503                 break;
 504
 505         default:
 506                 scnprintf(bf, sizeof(bf), "unknown attr type: %d",
 507                           evsel->attr.type);
 508                 break;
 509         }
 510
 511         evsel->name = strdup(bf);
 512
 513         return evsel->name ?: "unknown";
 514 }
 515
 516 const char *perf_evsel__group_name(struct perf_evsel *evsel)
 517 {
 518         return evsel->group_name ?: "anon group";
 519 }
 520
 521 int perf_evsel__group_desc(struct perf_evsel *evsel, char *buf, size_t size)
 522 {
 523         int ret;
 524         struct perf_evsel *pos;
 525         const char *group_name = perf_evsel__group_name(evsel);
 526
 527         ret = scnprintf(buf, size, "%s", group_name);
 528
 529         ret += scnprintf(buf + ret, size - ret, " { %s",
 530                          perf_evsel__name(evsel));
 531
 532         for_each_group_member(pos, evsel)
 533                 ret += scnprintf(buf + ret, size - ret, ", %s",
 534                                  perf_evsel__name(pos));
 535
 536         ret += scnprintf(buf + ret, size - ret, " }");
 537
 538         return ret;
 539 }
 540
 541 /*
 542  * The enable_on_exec/disabled value strategy:
 543  *
 544  *  1) For any type of traced program:
 545  *    - all independent events and group leaders are disabled
 546  *    - all group members are enabled
 547  *
 548  *     Group members are ruled by group leaders. They need to
 549  *     be enabled, because the group scheduling relies on that.
 550  *
 551  *  2) For traced programs executed by perf:
 552  *     - all independent events and group leaders have
 553  *       enable_on_exec set
 554  *     - we don't specifically enable or disable any event during
 555  *       the record command
 556  *
 557  *     Independent events and group leaders are initially disabled
 558  *     and get enabled by exec. Group members are ruled by group
 559  *     leaders as stated in 1).
 560  *
 561  *  3) For traced programs attached by perf (pid/tid):
 562  *     - we specifically enable or disable all events during
 563  *       the record command
 564  *
 565  *     When attaching events to already running traced we
 566  *     enable/disable events specifically, as there's no
 567  *     initial traced exec call.
 568  */
 569 void perf_evsel__config(struct perf_evsel *evsel,
 570                         struct perf_record_opts *opts)
 571 {
 572         struct perf_evsel *leader = evsel->leader;
 573         struct perf_event_attr *attr = &evsel->attr;
 574         int track = !evsel->idx; /* only the first counter needs these */
 575
 576         attr->sample_id_all = perf_missing_features.sample_id_all ? 0 : 1;
 577         attr->inherit       = !opts->no_inherit;
 578
 579         perf_evsel__set_sample_bit(evsel, IP);
 580         perf_evsel__set_sample_bit(evsel, TID);
 581
 582         if (evsel->sample_read) {
 583                 perf_evsel__set_sample_bit(evsel, READ);
 584
 585                 /*
 586                  * We need ID even in case of single event, because
 587                  * PERF_SAMPLE_READ process ID specific data.
 588                  */
 589                 perf_evsel__set_sample_id(evsel, false);
 590
 591                 /*
 592                  * Apply group format only if we belong to group
 593                  * with more than one members.
 594                  */
 595                 if (leader->nr_members > 1) {
 596                         attr->read_format |= PERF_FORMAT_GROUP;
 597                         attr->inherit = 0;
 598                 }
 599         }
 600
 601         /*
 602          * We default some events to a 1 default interval. But keep
 603          * it a weak assumption overridable by the user.
 604          */
 605         if (!attr->sample_period || (opts->user_freq != UINT_MAX &&
 606                                      opts->user_interval != ULLONG_MAX)) {
 607                 if (opts->freq) {
 608                         perf_evsel__set_sample_bit(evsel, PERIOD);
 609                         attr->freq              = 1;
 610                         attr->sample_freq       = opts->freq;
 611                 } else {
 612                         attr->sample_period = opts->default_interval;
 613                 }
 614         }
 615
 616         /*
 617          * Disable sampling for all group members other
 618          * than leader in case leader 'leads' the sampling.
 619          */
 620         if ((leader != evsel) && leader->sample_read) {
 621                 attr->sample_freq   = 0;
 622                 attr->sample_period = 0;
 623         }
 624
 625         if (opts->no_samples)
 626                 attr->sample_freq = 0;
 627
 628         if (opts->inherit_stat)
 629                 attr->inherit_stat = 1;
 630
 631         if (opts->sample_address) {
 632                 perf_evsel__set_sample_bit(evsel, ADDR);
 633                 attr->mmap_data = track;
 634         }
 635
 636         if (opts->call_graph) {
 637                 perf_evsel__set_sample_bit(evsel, CALLCHAIN);
 638
 639                 if (opts->call_graph == CALLCHAIN_DWARF) {
 640                         perf_evsel__set_sample_bit(evsel, REGS_USER);
 641                         perf_evsel__set_sample_bit(evsel, STACK_USER);
 642                         attr->sample_regs_user = PERF_REGS_MASK;
 643                         attr->sample_stack_user = opts->stack_dump_size;
 644                         attr->exclude_callchain_user = 1;
 645                 }
 646         }
 647
 648         if (perf_target__has_cpu(&opts->target))
 649                 perf_evsel__set_sample_bit(evsel, CPU);
 650
 651         if (opts->period)
 652                 perf_evsel__set_sample_bit(evsel, PERIOD);
 653
 654         if (!perf_missing_features.sample_id_all &&
 655             (opts->sample_time || !opts->no_inherit ||
 656              perf_target__has_cpu(&opts->target)))
 657                 perf_evsel__set_sample_bit(evsel, TIME);
 658
 659         if (opts->raw_samples) {
 660                 perf_evsel__set_sample_bit(evsel, TIME);
 661                 perf_evsel__set_sample_bit(evsel, RAW);
 662                 perf_evsel__set_sample_bit(evsel, CPU);
 663         }
 664
 665         if (opts->sample_address)
 666                 attr->sample_type       |= PERF_SAMPLE_DATA_SRC;
 667
 668         if (opts->no_delay) {
 669                 attr->watermark = 0;
 670                 attr->wakeup_events = 1;
 671         }
 672         if (opts->branch_stack) {
 673                 perf_evsel__set_sample_bit(evsel, BRANCH_STACK);
 674                 attr->branch_sample_type = opts->branch_stack;
 675         }
 676
 677         if (opts->sample_weight)
 678                 attr->sample_type       |= PERF_SAMPLE_WEIGHT;
 679
 680         attr->mmap  = track;
 681         attr->comm  = track;
 682
 683         /*
 684          * XXX see the function comment above
 685          *
 686          * Disabling only independent events or group leaders,
 687          * keeping group members enabled.
 688          */
 689         if (perf_evsel__is_group_leader(evsel))
 690                 attr->disabled = 1;
 691
 692         /*
 693          * Setting enable_on_exec for independent events and
 694          * group leaders for traced executed by perf.
 695          */
 696         if (perf_target__none(&opts->target) && perf_evsel__is_group_leader(evsel))
 697                 attr->enable_on_exec = 1;
 698 }
 699
 700 int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
 701 {
 702         int cpu, thread;
 703         evsel->fd = xyarray__new(ncpus, nthreads, sizeof(int));
 704
 705         if (evsel->fd) {
 706                 for (cpu = 0; cpu < ncpus; cpu++) {
 707                         for (thread = 0; thread < nthreads; thread++) {
 708                                 FD(evsel, cpu, thread) = -1;
 709                         }
 710                 }
 711         }
 712
 713         return evsel->fd != NULL ? 0 : -ENOMEM;
 714 }
 715
 716 static int perf_evsel__run_ioctl(struct perf_evsel *evsel, int ncpus, int nthreads,
 717                           int ioc,  void *arg)
 718 {
 719         int cpu, thread;
 720
 721         for (cpu = 0; cpu < ncpus; cpu++) {
 722                 for (thread = 0; thread < nthreads; thread++) {
 723                         int fd = FD(evsel, cpu, thread),
 724                             err = ioctl(fd, ioc, arg);
 725
 726                         if (err)
 727                                 return err;
 728                 }
 729         }
 730
 731         return 0;
 732 }
 733
 734 int perf_evsel__set_filter(struct perf_evsel *evsel, int ncpus, int nthreads,
 735                            const char *filter)
 736 {
 737         return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
 738                                      PERF_EVENT_IOC_SET_FILTER,
 739                                      (void *)filter);
 740 }
 741
 742 int perf_evsel__enable(struct perf_evsel *evsel, int ncpus, int nthreads)
 743 {
 744         return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
 745                                      PERF_EVENT_IOC_ENABLE,
 746                                      0);
 747 }
 748
 749 int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
 750 {
 751         evsel->sample_id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
 752         if (evsel->sample_id == NULL)
 753                 return -ENOMEM;
 754
 755         evsel->id = zalloc(ncpus * nthreads * sizeof(u64));
 756         if (evsel->id == NULL) {
 757                 xyarray__delete(evsel->sample_id);
 758                 evsel->sample_id = NULL;
 759                 return -ENOMEM;
 760         }
 761
 762         return 0;
 763 }
 764
 765 void perf_evsel__reset_counts(struct perf_evsel *evsel, int ncpus)
 766 {
 767         memset(evsel->counts, 0, (sizeof(*evsel->counts) +
 768                                  (ncpus * sizeof(struct perf_counts_values))));
 769 }
 770
 771 int perf_evsel__alloc_counts(struct perf_evsel *evsel, int ncpus)
 772 {
 773         evsel->counts = zalloc((sizeof(*evsel->counts) +
 774                                 (ncpus * sizeof(struct perf_counts_values))));
 775         return evsel->counts != NULL ? 0 : -ENOMEM;
 776 }
 777
 778 void perf_evsel__free_fd(struct perf_evsel *evsel)
 779 {
 780         xyarray__delete(evsel->fd);
 781         evsel->fd = NULL;
 782 }
 783
 784 void perf_evsel__free_id(struct perf_evsel *evsel)
 785 {
 786         xyarray__delete(evsel->sample_id);
 787         evsel->sample_id = NULL;
 788         free(evsel->id);
 789         evsel->id = NULL;
 790 }
 791
 792 void perf_evsel__close_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
 793 {
 794         int cpu, thread;
 795
 796         for (cpu = 0; cpu < ncpus; cpu++)
 797                 for (thread = 0; thread < nthreads; ++thread) {
 798                         close(FD(evsel, cpu, thread));
 799                         FD(evsel, cpu, thread) = -1;
 800                 }
 801 }
 802
 803 void perf_evsel__free_counts(struct perf_evsel *evsel)
 804 {
 805         free(evsel->counts);
 806 }
 807
 808 void perf_evsel__exit(struct perf_evsel *evsel)
 809 {
 810         assert(list_empty(&evsel->node));
 811         perf_evsel__free_fd(evsel);
 812         perf_evsel__free_id(evsel);
 813 }
 814
 815 void perf_evsel__delete(struct perf_evsel *evsel)
 816 {
 817         perf_evsel__exit(evsel);
 818         close_cgroup(evsel->cgrp);
 819         free(evsel->group_name);
 820         if (evsel->tp_format)
 821                 pevent_free_format(evsel->tp_format);
 822         free(evsel->name);
 823         free(evsel);
 824 }
 825
 826 static inline void compute_deltas(struct perf_evsel *evsel,
 827                                   int cpu,
 828                                   struct perf_counts_values *count)
 829 {
 830         struct perf_counts_values tmp;
 831
 832         if (!evsel->prev_raw_counts)
 833                 return;
 834
 835         if (cpu == -1) {
 836                 tmp = evsel->prev_raw_counts->aggr;
 837                 evsel->prev_raw_counts->aggr = *count;
 838         } else {
 839                 tmp = evsel->prev_raw_counts->cpu[cpu];
 840                 evsel->prev_raw_counts->cpu[cpu] = *count;
 841         }
 842
 843         count->val = count->val - tmp.val;
 844         count->ena = count->ena - tmp.ena;
 845         count->run = count->run - tmp.run;
 846 }
 847
 848 int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
 849                               int cpu, int thread, bool scale)
 850 {
 851         struct perf_counts_values count;
 852         size_t nv = scale ? 3 : 1;
 853
 854         if (FD(evsel, cpu, thread) < 0)
 855                 return -EINVAL;
 856
 857         if (evsel->counts == NULL && perf_evsel__alloc_counts(evsel, cpu + 1) < 0)
 858                 return -ENOMEM;
 859
 860         if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) < 0)
 861                 return -errno;
 862
 863         compute_deltas(evsel, cpu, &count);
 864
 865         if (scale) {
 866                 if (count.run == 0)
 867                         count.val = 0;
 868                 else if (count.run < count.ena)
 869                         count.val = (u64)((double)count.val * count.ena / count.run + 0.5);
 870         } else
 871                 count.ena = count.run = 0;
 872
 873         evsel->counts->cpu[cpu] = count;
 874         return 0;
 875 }
 876
 877 int __perf_evsel__read(struct perf_evsel *evsel,
 878                        int ncpus, int nthreads, bool scale)
 879 {
 880         size_t nv = scale ? 3 : 1;
 881         int cpu, thread;
 882         struct perf_counts_values *aggr = &evsel->counts->aggr, count;
 883
 884         aggr->val = aggr->ena = aggr->run = 0;
 885
 886         for (cpu = 0; cpu < ncpus; cpu++) {
 887                 for (thread = 0; thread < nthreads; thread++) {
 888                         if (FD(evsel, cpu, thread) < 0)
 889                                 continue;
 890
 891                         if (readn(FD(evsel, cpu, thread),
 892                                   &count, nv * sizeof(u64)) < 0)
 893                                 return -errno;
 894
 895                         aggr->val += count.val;
 896                         if (scale) {
 897                                 aggr->ena += count.ena;
 898                                 aggr->run += count.run;
 899                         }
 900                 }
 901         }
 902
 903         compute_deltas(evsel, -1, aggr);
 904
 905         evsel->counts->scaled = 0;
 906         if (scale) {
 907                 if (aggr->run == 0) {
 908                         evsel->counts->scaled = -1;
 909                         aggr->val = 0;
 910                         return 0;
 911                 }
 912
 913                 if (aggr->run < aggr->ena) {
 914                         evsel->counts->scaled = 1;
 915                         aggr->val = (u64)((double)aggr->val * aggr->ena / aggr->run + 0.5);
 916                 }
 917         } else
 918                 aggr->ena = aggr->run = 0;
 919
 920         return 0;
 921 }
 922
 923 static int get_group_fd(struct perf_evsel *evsel, int cpu, int thread)
 924 {
 925         struct perf_evsel *leader = evsel->leader;
 926         int fd;
 927
 928         if (perf_evsel__is_group_leader(evsel))
 929                 return -1;
 930
 931         /*
 932          * Leader must be already processed/open,
 933          * if not it's a bug.
 934          */
 935         BUG_ON(!leader->fd);
 936
 937         fd = FD(leader, cpu, thread);
 938         BUG_ON(fd == -1);
 939
 940         return fd;
 941 }
 942
 943 #define __PRINT_ATTR(fmt, cast, field)  \
 944         fprintf(fp, "  %-19s "fmt"\n", #field, cast attr->field)
 945
 946 #define PRINT_ATTR_U32(field)  __PRINT_ATTR("%u" , , field)
 947 #define PRINT_ATTR_X32(field)  __PRINT_ATTR("%#x", , field)
 948 #define PRINT_ATTR_U64(field)  __PRINT_ATTR("%" PRIu64, (uint64_t), field)
 949 #define PRINT_ATTR_X64(field)  __PRINT_ATTR("%#"PRIx64, (uint64_t), field)
 950
 951 #define PRINT_ATTR2N(name1, field1, name2, field2)      \
 952         fprintf(fp, "  %-19s %u    %-19s %u\n",         \
 953         name1, attr->field1, name2, attr->field2)
 954
 955 #define PRINT_ATTR2(field1, field2) \
 956         PRINT_ATTR2N(#field1, field1, #field2, field2)
 957
 958 static size_t perf_event_attr__fprintf(struct perf_event_attr *attr, FILE *fp)
 959 {
 960         size_t ret = 0;
 961
 962         ret += fprintf(fp, "%.60s\n", graph_dotted_line);
 963         ret += fprintf(fp, "perf_event_attr:\n");
 964
 965         ret += PRINT_ATTR_U32(type);
 966         ret += PRINT_ATTR_U32(size);
 967         ret += PRINT_ATTR_X64(config);
 968         ret += PRINT_ATTR_U64(sample_period);
 969         ret += PRINT_ATTR_U64(sample_freq);
 970         ret += PRINT_ATTR_X64(sample_type);
 971         ret += PRINT_ATTR_X64(read_format);
 972
 973         ret += PRINT_ATTR2(disabled, inherit);
 974         ret += PRINT_ATTR2(pinned, exclusive);
 975         ret += PRINT_ATTR2(exclude_user, exclude_kernel);
 976         ret += PRINT_ATTR2(exclude_hv, exclude_idle);
 977         ret += PRINT_ATTR2(mmap, comm);
 978         ret += PRINT_ATTR2(freq, inherit_stat);
 979         ret += PRINT_ATTR2(enable_on_exec, task);
 980         ret += PRINT_ATTR2(watermark, precise_ip);
 981         ret += PRINT_ATTR2(mmap_data, sample_id_all);
 982         ret += PRINT_ATTR2(exclude_host, exclude_guest);
 983         ret += PRINT_ATTR2N("excl.callchain_kern", exclude_callchain_kernel,
 984                             "excl.callchain_user", exclude_callchain_user);
 985
 986         ret += PRINT_ATTR_U32(wakeup_events);
 987         ret += PRINT_ATTR_U32(wakeup_watermark);
 988         ret += PRINT_ATTR_X32(bp_type);
 989         ret += PRINT_ATTR_X64(bp_addr);
 990         ret += PRINT_ATTR_X64(config1);
 991         ret += PRINT_ATTR_U64(bp_len);
 992         ret += PRINT_ATTR_X64(config2);
 993         ret += PRINT_ATTR_X64(branch_sample_type);
 994         ret += PRINT_ATTR_X64(sample_regs_user);
 995         ret += PRINT_ATTR_U32(sample_stack_user);
 996
 997         ret += fprintf(fp, "%.60s\n", graph_dotted_line);
 998
 999         return ret;
1000 }
1001
1002 static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1003                               struct thread_map *threads)
1004 {
1005         int cpu, thread;
1006         unsigned long flags = 0;
1007         int pid = -1, err;
1008         enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;
1009
1010         if (evsel->fd == NULL &&
1011             perf_evsel__alloc_fd(evsel, cpus->nr, threads->nr) < 0)
1012                 return -ENOMEM;
1013
1014         if (evsel->cgrp) {
1015                 flags = PERF_FLAG_PID_CGROUP;
1016                 pid = evsel->cgrp->fd;
1017         }
1018
1019 fallback_missing_features:
1020         if (perf_missing_features.mmap2)
1021                 evsel->attr.mmap2 = 0;
1022         if (perf_missing_features.exclude_guest)
1023                 evsel->attr.exclude_guest = evsel->attr.exclude_host = 0;
1024 retry_sample_id:
1025         if (perf_missing_features.sample_id_all)
1026                 evsel->attr.sample_id_all = 0;
1027
1028         if (verbose >= 2)
1029                 perf_event_attr__fprintf(&evsel->attr, stderr);
1030
1031         for (cpu = 0; cpu < cpus->nr; cpu++) {
1032
1033                 for (thread = 0; thread < threads->nr; thread++) {
1034                         int group_fd;
1035
1036                         if (!evsel->cgrp)
1037                                 pid = threads->map[thread];
1038
1039                         group_fd = get_group_fd(evsel, cpu, thread);
1040 retry_open:
1041                         pr_debug2("perf_event_open: pid %d  cpu %d  group_fd %d  flags %#lx\n",
1042                                   pid, cpus->map[cpu], group_fd, flags);
1043
1044                         FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr,
1045                                                                      pid,
1046                                                                      cpus->map[cpu],
1047                                                                      group_fd, flags);
1048                         if (FD(evsel, cpu, thread) < 0) {
1049                                 err = -errno;
1050                                 goto try_fallback;
1051                         }
1052                         set_rlimit = NO_CHANGE;
1053                 }
1054         }
1055
1056         return 0;
1057
1058 try_fallback:
1059         /*
1060          * perf stat needs between 5 and 22 fds per CPU. When we run out
1061          * of them try to increase the limits.
1062          */
1063         if (err == -EMFILE && set_rlimit < INCREASED_MAX) {
1064                 struct rlimit l;
1065                 int old_errno = errno;
1066
1067                 if (getrlimit(RLIMIT_NOFILE, &l) == 0) {
1068                         if (set_rlimit == NO_CHANGE)
1069                                 l.rlim_cur = l.rlim_max;
1070                         else {
1071                                 l.rlim_cur = l.rlim_max + 1000;
1072                                 l.rlim_max = l.rlim_cur;
1073                         }
1074                         if (setrlimit(RLIMIT_NOFILE, &l) == 0) {
1075                                 set_rlimit++;
1076                                 errno = old_errno;
1077                                 goto retry_open;
1078                         }
1079                 }
1080                 errno = old_errno;
1081         }
1082
1083         if (err != -EINVAL || cpu > 0 || thread > 0)
1084                 goto out_close;
1085
1086         if (!perf_missing_features.mmap2 && evsel->attr.mmap2) {
1087                 perf_missing_features.mmap2 = true;
1088                 goto fallback_missing_features;
1089         } else if (!perf_missing_features.exclude_guest &&
1090                    (evsel->attr.exclude_guest || evsel->attr.exclude_host)) {
1091                 perf_missing_features.exclude_guest = true;
1092                 goto fallback_missing_features;
1093         } else if (!perf_missing_features.sample_id_all) {
1094                 perf_missing_features.sample_id_all = true;
1095                 goto retry_sample_id;
1096         }
1097
1098 out_close:
1099         do {
1100                 while (--thread >= 0) {
1101                         close(FD(evsel, cpu, thread));
1102                         FD(evsel, cpu, thread) = -1;
1103                 }
1104                 thread = threads->nr;
1105         } while (--cpu >= 0);
1106         return err;
1107 }
1108
1109 void perf_evsel__close(struct perf_evsel *evsel, int ncpus, int nthreads)
1110 {
1111         if (evsel->fd == NULL)
1112                 return;
1113
1114         perf_evsel__close_fd(evsel, ncpus, nthreads);
1115         perf_evsel__free_fd(evsel);
1116         evsel->fd = NULL;
1117 }
1118
1119 static struct {
1120         struct cpu_map map;
1121         int cpus[1];
1122 } empty_cpu_map = {
1123         .map.nr = 1,
1124         .cpus   = { -1, },
1125 };
1126
1127 static struct {
1128         struct thread_map map;
1129         int threads[1];
1130 } empty_thread_map = {
1131         .map.nr  = 1,
1132         .threads = { -1, },
1133 };
1134
1135 int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1136                      struct thread_map *threads)
1137 {
1138         if (cpus == NULL) {
1139                 /* Work around old compiler warnings about strict aliasing */
1140                 cpus = &empty_cpu_map.map;
1141         }
1142
1143         if (threads == NULL)
1144                 threads = &empty_thread_map.map;
1145
1146         return __perf_evsel__open(evsel, cpus, threads);
1147 }
1148
1149 int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
1150                              struct cpu_map *cpus)
1151 {
1152         return __perf_evsel__open(evsel, cpus, &empty_thread_map.map);
1153 }
1154
1155 int perf_evsel__open_per_thread(struct perf_evsel *evsel,
1156                                 struct thread_map *threads)
1157 {
1158         return __perf_evsel__open(evsel, &empty_cpu_map.map, threads);
1159 }
1160
1161 static int perf_evsel__parse_id_sample(const struct perf_evsel *evsel,
1162                                        const union perf_event *event,
1163                                        struct perf_sample *sample)
1164 {
1165         u64 type = evsel->attr.sample_type;
1166         const u64 *array = event->sample.array;
1167         bool swapped = evsel->needs_swap;
1168         union u64_swap u;
1169
1170         array += ((event->header.size -
1171                    sizeof(event->header)) / sizeof(u64)) - 1;
1172
1173         if (type & PERF_SAMPLE_IDENTIFIER) {
1174                 sample->id = *array;
1175                 array--;
1176         }
1177
1178         if (type & PERF_SAMPLE_CPU) {
1179                 u.val64 = *array;
1180                 if (swapped) {
1181                         /* undo swap of u64, then swap on individual u32s */
1182                         u.val64 = bswap_64(u.val64);
1183                         u.val32[0] = bswap_32(u.val32[0]);
1184                 }
1185
1186                 sample->cpu = u.val32[0];
1187                 array--;
1188         }
1189
1190         if (type & PERF_SAMPLE_STREAM_ID) {
1191                 sample->stream_id = *array;
1192                 array--;
1193         }
1194
1195         if (type & PERF_SAMPLE_ID) {
1196                 sample->id = *array;
1197                 array--;
1198         }
1199
1200         if (type & PERF_SAMPLE_TIME) {
1201                 sample->time = *array;
1202                 array--;
1203         }
1204
1205         if (type & PERF_SAMPLE_TID) {
1206                 u.val64 = *array;
1207                 if (swapped) {
1208                         /* undo swap of u64, then swap on individual u32s */
1209                         u.val64 = bswap_64(u.val64);
1210                         u.val32[0] = bswap_32(u.val32[0]);
1211                         u.val32[1] = bswap_32(u.val32[1]);
1212                 }
1213
1214                 sample->pid = u.val32[0];
1215                 sample->tid = u.val32[1];
1216         }
1217
1218         return 0;
1219 }
1220
1221 static inline bool overflow(const void *endp, u16 max_size, const void *offset,
1222                             u64 size)
1223 {
1224         return size > max_size || offset + size > endp;
1225 }
1226
1227 #define OVERFLOW_CHECK(offset, size, max_size)                          \
1228         do {                                                            \
1229                 if (overflow(endp, (max_size), (offset), (size)))       \
1230                         return -EFAULT;                                 \
1231         } while (0)
1232
1233 #define OVERFLOW_CHECK_u64(offset) \
1234         OVERFLOW_CHECK(offset, sizeof(u64), sizeof(u64))
1235
1236 int perf_evsel__parse_sample(struct perf_evsel *evsel, union perf_event *event,
1237                              struct perf_sample *data)
1238 {
1239         u64 type = evsel->attr.sample_type;
1240         bool swapped = evsel->needs_swap;
1241         const u64 *array;
1242         u16 max_size = event->header.size;
1243         const void *endp = (void *)event + max_size;
1244         u64 sz;
1245
1246         /*
1247          * used for cross-endian analysis. See git commit 65014ab3
1248          * for why this goofiness is needed.
1249          */
1250         union u64_swap u;
1251
1252         memset(data, 0, sizeof(*data));
1253         data->cpu = data->pid = data->tid = -1;
1254         data->stream_id = data->id = data->time = -1ULL;
1255         data->period = 1;
1256         data->weight = 0;
1257
1258         if (event->header.type != PERF_RECORD_SAMPLE) {
1259                 if (!evsel->attr.sample_id_all)
1260                         return 0;
1261                 return perf_evsel__parse_id_sample(evsel, event, data);
1262         }
1263
1264         array = event->sample.array;
1265
1266         /*
1267          * The evsel's sample_size is based on PERF_SAMPLE_MASK which includes
1268          * up to PERF_SAMPLE_PERIOD.  After that overflow() must be used to
1269          * check the format does not go past the end of the event.
1270          */
1271         if (evsel->sample_size + sizeof(event->header) > event->header.size)
1272                 return -EFAULT;
1273
1274         data->id = -1ULL;
1275         if (type & PERF_SAMPLE_IDENTIFIER) {
1276                 data->id = *array;
1277                 array++;
1278         }
1279
1280         if (type & PERF_SAMPLE_IP) {
1281                 data->ip = *array;
1282                 array++;
1283         }
1284
1285         if (type & PERF_SAMPLE_TID) {
1286                 u.val64 = *array;
1287                 if (swapped) {
1288                         /* undo swap of u64, then swap on individual u32s */
1289                         u.val64 = bswap_64(u.val64);
1290                         u.val32[0] = bswap_32(u.val32[0]);
1291                         u.val32[1] = bswap_32(u.val32[1]);
1292                 }
1293
1294                 data->pid = u.val32[0];
1295                 data->tid = u.val32[1];
1296                 array++;
1297         }
1298
1299         if (type & PERF_SAMPLE_TIME) {
1300                 data->time = *array;
1301                 array++;
1302         }
1303
1304         data->addr = 0;
1305         if (type & PERF_SAMPLE_ADDR) {
1306                 data->addr = *array;
1307                 array++;
1308         }
1309
1310         if (type & PERF_SAMPLE_ID) {
1311                 data->id = *array;
1312                 array++;
1313         }
1314
1315         if (type & PERF_SAMPLE_STREAM_ID) {
1316                 data->stream_id = *array;
1317                 array++;
1318         }
1319
1320         if (type & PERF_SAMPLE_CPU) {
1321
1322                 u.val64 = *array;
1323                 if (swapped) {
1324                         /* undo swap of u64, then swap on individual u32s */
1325                         u.val64 = bswap_64(u.val64);
1326                         u.val32[0] = bswap_32(u.val32[0]);
1327                 }
1328
1329                 data->cpu = u.val32[0];
1330                 array++;
1331         }
1332
1333         if (type & PERF_SAMPLE_PERIOD) {
1334                 data->period = *array;
1335                 array++;
1336         }
1337
1338         if (type & PERF_SAMPLE_READ) {
1339                 u64 read_format = evsel->attr.read_format;
1340
1341                 OVERFLOW_CHECK_u64(array);
1342                 if (read_format & PERF_FORMAT_GROUP)
1343                         data->read.group.nr = *array;
1344                 else
1345                         data->read.one.value = *array;
1346
1347                 array++;
1348
1349                 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1350                         OVERFLOW_CHECK_u64(array);
1351                         data->read.time_enabled = *array;
1352                         array++;
1353                 }
1354
1355                 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1356                         OVERFLOW_CHECK_u64(array);
1357                         data->read.time_running = *array;
1358                         array++;
1359                 }
1360
1361                 /* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1362                 if (read_format & PERF_FORMAT_GROUP) {
1363                         const u64 max_group_nr = UINT64_MAX /
1364                                         sizeof(struct sample_read_value);
1365
1366                         if (data->read.group.nr > max_group_nr)
1367                                 return -EFAULT;
1368                         sz = data->read.group.nr *
1369                              sizeof(struct sample_read_value);
1370                         OVERFLOW_CHECK(array, sz, max_size);
1371                         data->read.group.values =
1372                                         (struct sample_read_value *)array;
1373                         array = (void *)array + sz;
1374                 } else {
1375                         OVERFLOW_CHECK_u64(array);
1376                         data->read.one.id = *array;
1377                         array++;
1378                 }
1379         }
1380
1381         if (type & PERF_SAMPLE_CALLCHAIN) {
1382                 const u64 max_callchain_nr = UINT64_MAX / sizeof(u64);
1383
1384                 OVERFLOW_CHECK_u64(array);
1385                 data->callchain = (struct ip_callchain *)array++;
1386                 if (data->callchain->nr > max_callchain_nr)
1387                         return -EFAULT;
1388                 sz = data->callchain->nr * sizeof(u64);
1389                 OVERFLOW_CHECK(array, sz, max_size);
1390                 array = (void *)array + sz;
1391         }
1392
1393         if (type & PERF_SAMPLE_RAW) {
1394                 OVERFLOW_CHECK_u64(array);
1395                 u.val64 = *array;
1396                 if (WARN_ONCE(swapped,
1397                               "Endianness of raw data not corrected!\n")) {
1398                         /* undo swap of u64, then swap on individual u32s */
1399                         u.val64 = bswap_64(u.val64);
1400                         u.val32[0] = bswap_32(u.val32[0]);
1401                         u.val32[1] = bswap_32(u.val32[1]);
1402                 }
1403                 data->raw_size = u.val32[0];
1404                 array = (void *)array + sizeof(u32);
1405
1406                 OVERFLOW_CHECK(array, data->raw_size, max_size);
1407                 data->raw_data = (void *)array;
1408                 array = (void *)array + data->raw_size;
1409         }
1410
1411         if (type & PERF_SAMPLE_BRANCH_STACK) {
1412                 const u64 max_branch_nr = UINT64_MAX /
1413                                           sizeof(struct branch_entry);
1414
1415                 OVERFLOW_CHECK_u64(array);
1416                 data->branch_stack = (struct branch_stack *)array++;
1417
1418                 if (data->branch_stack->nr > max_branch_nr)
1419                         return -EFAULT;
1420                 sz = data->branch_stack->nr * sizeof(struct branch_entry);
1421                 OVERFLOW_CHECK(array, sz, max_size);
1422                 array = (void *)array + sz;
1423         }
1424
1425         if (type & PERF_SAMPLE_REGS_USER) {
1426                 OVERFLOW_CHECK_u64(array);
1427                 data->user_regs.abi = *array;
1428                 array++;
1429
1430                 if (data->user_regs.abi) {
1431                         u64 regs_user = evsel->attr.sample_regs_user;
1432
1433                         sz = hweight_long(regs_user) * sizeof(u64);
1434                         OVERFLOW_CHECK(array, sz, max_size);
1435                         data->user_regs.regs = (u64 *)array;
1436                         array = (void *)array + sz;
1437                 }
1438         }
1439
1440         if (type & PERF_SAMPLE_STACK_USER) {
1441                 OVERFLOW_CHECK_u64(array);
1442                 sz = *array++;
1443
1444                 data->user_stack.offset = ((char *)(array - 1)
1445                                           - (char *) event);
1446
1447                 if (!sz) {
1448                         data->user_stack.size = 0;
1449                 } else {
1450                         OVERFLOW_CHECK(array, sz, max_size);
1451                         data->user_stack.data = (char *)array;
1452                         array = (void *)array + sz;
1453                         OVERFLOW_CHECK_u64(array);
1454                         data->user_stack.size = *array++;
1455                 }
1456         }
1457
1458         data->weight = 0;
1459         if (type & PERF_SAMPLE_WEIGHT) {
1460                 OVERFLOW_CHECK_u64(array);
1461                 data->weight = *array;
1462                 array++;
1463         }
1464
1465         data->data_src = PERF_MEM_DATA_SRC_NONE;
1466         if (type & PERF_SAMPLE_DATA_SRC) {
1467                 OVERFLOW_CHECK_u64(array);
1468                 data->data_src = *array;
1469                 array++;
1470         }
1471
1472         return 0;
1473 }
1474
1475 size_t perf_event__sample_event_size(const struct perf_sample *sample, u64 type,
1476                                      u64 sample_regs_user, u64 read_format)
1477 {
1478         size_t sz, result = sizeof(struct sample_event);
1479
1480         if (type & PERF_SAMPLE_IDENTIFIER)
1481                 result += sizeof(u64);
1482
1483         if (type & PERF_SAMPLE_IP)
1484                 result += sizeof(u64);
1485
1486         if (type & PERF_SAMPLE_TID)
1487                 result += sizeof(u64);
1488
1489         if (type & PERF_SAMPLE_TIME)
1490                 result += sizeof(u64);
1491
1492         if (type & PERF_SAMPLE_ADDR)
1493                 result += sizeof(u64);
1494
1495         if (type & PERF_SAMPLE_ID)
1496                 result += sizeof(u64);
1497
1498         if (type & PERF_SAMPLE_STREAM_ID)
1499                 result += sizeof(u64);
1500
1501         if (type & PERF_SAMPLE_CPU)
1502                 result += sizeof(u64);
1503
1504         if (type & PERF_SAMPLE_PERIOD)
1505                 result += sizeof(u64);
1506
1507         if (type & PERF_SAMPLE_READ) {
1508                 result += sizeof(u64);
1509                 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
1510                         result += sizeof(u64);
1511                 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
1512                         result += sizeof(u64);
1513                 /* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1514                 if (read_format & PERF_FORMAT_GROUP) {
1515                         sz = sample->read.group.nr *
1516                              sizeof(struct sample_read_value);
1517                         result += sz;
1518                 } else {
1519                         result += sizeof(u64);
1520                 }
1521         }
1522
1523         if (type & PERF_SAMPLE_CALLCHAIN) {
1524                 sz = (sample->callchain->nr + 1) * sizeof(u64);
1525                 result += sz;
1526         }
1527
1528         if (type & PERF_SAMPLE_RAW) {
1529                 result += sizeof(u32);
1530                 result += sample->raw_size;
1531         }
1532
1533         if (type & PERF_SAMPLE_BRANCH_STACK) {
1534                 sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1535                 sz += sizeof(u64);
1536                 result += sz;
1537         }
1538
1539         if (type & PERF_SAMPLE_REGS_USER) {
1540                 if (sample->user_regs.abi) {
1541                         result += sizeof(u64);
1542                         sz = hweight_long(sample_regs_user) * sizeof(u64);
1543                         result += sz;
1544                 } else {
1545                         result += sizeof(u64);
1546                 }
1547         }
1548
1549         if (type & PERF_SAMPLE_STACK_USER) {
1550                 sz = sample->user_stack.size;
1551                 result += sizeof(u64);
1552                 if (sz) {
1553                         result += sz;
1554                         result += sizeof(u64);
1555                 }
1556         }
1557
1558         if (type & PERF_SAMPLE_WEIGHT)
1559                 result += sizeof(u64);
1560
1561         if (type & PERF_SAMPLE_DATA_SRC)
1562                 result += sizeof(u64);
1563
1564         return result;
1565 }
1566
1567 int perf_event__synthesize_sample(union perf_event *event, u64 type,
1568                                   u64 sample_regs_user, u64 read_format,
1569                                   const struct perf_sample *sample,
1570                                   bool swapped)
1571 {
1572         u64 *array;
1573         size_t sz;
1574         /*
1575          * used for cross-endian analysis. See git commit 65014ab3
1576          * for why this goofiness is needed.
1577          */
1578         union u64_swap u;
1579
1580         array = event->sample.array;
1581
1582         if (type & PERF_SAMPLE_IDENTIFIER) {
1583                 *array = sample->id;
1584                 array++;
1585         }
1586
1587         if (type & PERF_SAMPLE_IP) {
1588                 *array = sample->ip;
1589                 array++;
1590         }
1591
1592         if (type & PERF_SAMPLE_TID) {
1593                 u.val32[0] = sample->pid;
1594                 u.val32[1] = sample->tid;
1595                 if (swapped) {
1596                         /*
1597                          * Inverse of what is done in perf_evsel__parse_sample
1598                          */
1599                         u.val32[0] = bswap_32(u.val32[0]);
1600                         u.val32[1] = bswap_32(u.val32[1]);
1601                         u.val64 = bswap_64(u.val64);
1602                 }
1603
1604                 *array = u.val64;
1605                 array++;
1606         }
1607
1608         if (type & PERF_SAMPLE_TIME) {
1609                 *array = sample->time;
1610                 array++;
1611         }
1612
1613         if (type & PERF_SAMPLE_ADDR) {
1614                 *array = sample->addr;
1615                 array++;
1616         }
1617
1618         if (type & PERF_SAMPLE_ID) {
1619                 *array = sample->id;
1620                 array++;
1621         }
1622
1623         if (type & PERF_SAMPLE_STREAM_ID) {
1624                 *array = sample->stream_id;
1625                 array++;
1626         }
1627
1628         if (type & PERF_SAMPLE_CPU) {
1629                 u.val32[0] = sample->cpu;
1630                 if (swapped) {
1631                         /*
1632                          * Inverse of what is done in perf_evsel__parse_sample
1633                          */
1634                         u.val32[0] = bswap_32(u.val32[0]);
1635                         u.val64 = bswap_64(u.val64);
1636                 }
1637                 *array = u.val64;
1638                 array++;
1639         }
1640
1641         if (type & PERF_SAMPLE_PERIOD) {
1642                 *array = sample->period;
1643                 array++;
1644         }
1645
1646         if (type & PERF_SAMPLE_READ) {
1647                 if (read_format & PERF_FORMAT_GROUP)
1648                         *array = sample->read.group.nr;
1649                 else
1650                         *array = sample->read.one.value;
1651                 array++;
1652
1653                 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1654                         *array = sample->read.time_enabled;
1655                         array++;
1656                 }
1657
1658                 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1659                         *array = sample->read.time_running;
1660                         array++;
1661                 }
1662
1663                 /* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1664                 if (read_format & PERF_FORMAT_GROUP) {
1665                         sz = sample->read.group.nr *
1666                              sizeof(struct sample_read_value);
1667                         memcpy(array, sample->read.group.values, sz);
1668                         array = (void *)array + sz;
1669                 } else {
1670                         *array = sample->read.one.id;
1671                         array++;
1672                 }
1673         }
1674
1675         if (type & PERF_SAMPLE_CALLCHAIN) {
1676                 sz = (sample->callchain->nr + 1) * sizeof(u64);
1677                 memcpy(array, sample->callchain, sz);
1678                 array = (void *)array + sz;
1679         }
1680
1681         if (type & PERF_SAMPLE_RAW) {
1682                 u.val32[0] = sample->raw_size;
1683                 if (WARN_ONCE(swapped,
1684                               "Endianness of raw data not corrected!\n")) {
1685                         /*
1686                          * Inverse of what is done in perf_evsel__parse_sample
1687                          */
1688                         u.val32[0] = bswap_32(u.val32[0]);
1689                         u.val32[1] = bswap_32(u.val32[1]);
1690                         u.val64 = bswap_64(u.val64);
1691                 }
1692                 *array = u.val64;
1693                 array = (void *)array + sizeof(u32);
1694
1695                 memcpy(array, sample->raw_data, sample->raw_size);
1696                 array = (void *)array + sample->raw_size;
1697         }
1698
1699         if (type & PERF_SAMPLE_BRANCH_STACK) {
1700                 sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1701                 sz += sizeof(u64);
1702                 memcpy(array, sample->branch_stack, sz);
1703                 array = (void *)array + sz;
1704         }
1705
1706         if (type & PERF_SAMPLE_REGS_USER) {
1707                 if (sample->user_regs.abi) {
1708                         *array++ = sample->user_regs.abi;
1709                         sz = hweight_long(sample_regs_user) * sizeof(u64);
1710                         memcpy(array, sample->user_regs.regs, sz);
1711                         array = (void *)array + sz;
1712                 } else {
1713                         *array++ = 0;
1714                 }
1715         }
1716
1717         if (type & PERF_SAMPLE_STACK_USER) {
1718                 sz = sample->user_stack.size;
1719                 *array++ = sz;
1720                 if (sz) {
1721                         memcpy(array, sample->user_stack.data, sz);
1722                         array = (void *)array + sz;
1723                         *array++ = sz;
1724                 }
1725         }
1726
1727         if (type & PERF_SAMPLE_WEIGHT) {
1728                 *array = sample->weight;
1729                 array++;
1730         }
1731
1732         if (type & PERF_SAMPLE_DATA_SRC) {
1733                 *array = sample->data_src;
1734                 array++;
1735         }
1736
1737         return 0;
1738 }
1739
1740 struct format_field *perf_evsel__field(struct perf_evsel *evsel, const char *name)
1741 {
1742         return pevent_find_field(evsel->tp_format, name);
1743 }
1744
1745 void *perf_evsel__rawptr(struct perf_evsel *evsel, struct perf_sample *sample,
1746                          const char *name)
1747 {
1748         struct format_field *field = perf_evsel__field(evsel, name);
1749         int offset;
1750
1751         if (!field)
1752                 return NULL;
1753
1754         offset = field->offset;
1755
1756         if (field->flags & FIELD_IS_DYNAMIC) {
1757                 offset = *(int *)(sample->raw_data + field->offset);
1758                 offset &= 0xffff;
1759         }
1760
1761         return sample->raw_data + offset;
1762 }
1763
1764 u64 perf_evsel__intval(struct perf_evsel *evsel, struct perf_sample *sample,
1765                        const char *name)
1766 {
1767         struct format_field *field = perf_evsel__field(evsel, name);
1768         void *ptr;
1769         u64 value;
1770
1771         if (!field)
1772                 return 0;
1773
1774         ptr = sample->raw_data + field->offset;
1775
1776         switch (field->size) {
1777         case 1:
1778                 return *(u8 *)ptr;
1779         case 2:
1780                 value = *(u16 *)ptr;
1781                 break;
1782         case 4:
1783                 value = *(u32 *)ptr;
1784                 break;
1785         case 8:
1786                 value = *(u64 *)ptr;
1787                 break;
1788         default:
1789                 return 0;
1790         }
1791
1792         if (!evsel->needs_swap)
1793                 return value;
1794
1795         switch (field->size) {
1796         case 2:
1797                 return bswap_16(value);
1798         case 4:
1799                 return bswap_32(value);
1800         case 8:
1801                 return bswap_64(value);
1802         default:
1803                 return 0;
1804         }
1805
1806         return 0;
1807 }
1808
1809 static int comma_fprintf(FILE *fp, bool *first, const char *fmt, ...)
1810 {
1811         va_list args;
1812         int ret = 0;
1813
1814         if (!*first) {
1815                 ret += fprintf(fp, ",");
1816         } else {
1817                 ret += fprintf(fp, ":");
1818                 *first = false;
1819         }
1820
1821         va_start(args, fmt);
1822         ret += vfprintf(fp, fmt, args);
1823         va_end(args);
1824         return ret;
1825 }
1826
1827 static int __if_fprintf(FILE *fp, bool *first, const char *field, u64 value)
1828 {
1829         if (value == 0)
1830                 return 0;
1831
1832         return comma_fprintf(fp, first, " %s: %" PRIu64, field, value);
1833 }
1834
1835 #define if_print(field) printed += __if_fprintf(fp, &first, #field, evsel->attr.field)
1836
1837 struct bit_names {
1838         int bit;
1839         const char *name;
1840 };
1841
1842 static int bits__fprintf(FILE *fp, const char *field, u64 value,
1843                          struct bit_names *bits, bool *first)
1844 {
1845         int i = 0, printed = comma_fprintf(fp, first, " %s: ", field);
1846         bool first_bit = true;
1847
1848         do {
1849                 if (value & bits[i].bit) {
1850                         printed += fprintf(fp, "%s%s", first_bit ? "" : "|", bits[i].name);
1851                         first_bit = false;
1852                 }
1853         } while (bits[++i].name != NULL);
1854
1855         return printed;
1856 }
1857
1858 static int sample_type__fprintf(FILE *fp, bool *first, u64 value)
1859 {
1860 #define bit_name(n) { PERF_SAMPLE_##n, #n }
1861         struct bit_names bits[] = {
1862                 bit_name(IP), bit_name(TID), bit_name(TIME), bit_name(ADDR),
1863                 bit_name(READ), bit_name(CALLCHAIN), bit_name(ID), bit_name(CPU),
1864                 bit_name(PERIOD), bit_name(STREAM_ID), bit_name(RAW),
1865                 bit_name(BRANCH_STACK), bit_name(REGS_USER), bit_name(STACK_USER),
1866                 bit_name(IDENTIFIER),
1867                 { .name = NULL, }
1868         };
1869 #undef bit_name
1870         return bits__fprintf(fp, "sample_type", value, bits, first);
1871 }
1872
1873 static int read_format__fprintf(FILE *fp, bool *first, u64 value)
1874 {
1875 #define bit_name(n) { PERF_FORMAT_##n, #n }
1876         struct bit_names bits[] = {
1877                 bit_name(TOTAL_TIME_ENABLED), bit_name(TOTAL_TIME_RUNNING),
1878                 bit_name(ID), bit_name(GROUP),
1879                 { .name = NULL, }
1880         };
1881 #undef bit_name
1882         return bits__fprintf(fp, "read_format", value, bits, first);
1883 }
1884
1885 int perf_evsel__fprintf(struct perf_evsel *evsel,
1886                         struct perf_attr_details *details, FILE *fp)
1887 {
1888         bool first = true;
1889         int printed = 0;
1890
1891         if (details->event_group) {
1892                 struct perf_evsel *pos;
1893
1894                 if (!perf_evsel__is_group_leader(evsel))
1895                         return 0;
1896
1897                 if (evsel->nr_members > 1)
1898                         printed += fprintf(fp, "%s{", evsel->group_name ?: "");
1899
1900                 printed += fprintf(fp, "%s", perf_evsel__name(evsel));
1901                 for_each_group_member(pos, evsel)
1902                         printed += fprintf(fp, ",%s", perf_evsel__name(pos));
1903
1904                 if (evsel->nr_members > 1)
1905                         printed += fprintf(fp, "}");
1906                 goto out;
1907         }
1908
1909         printed += fprintf(fp, "%s", perf_evsel__name(evsel));
1910
1911         if (details->verbose || details->freq) {
1912                 printed += comma_fprintf(fp, &first, " sample_freq=%" PRIu64,
1913                                          (u64)evsel->attr.sample_freq);
1914         }
1915
1916         if (details->verbose) {
1917                 if_print(type);
1918                 if_print(config);
1919                 if_print(config1);
1920                 if_print(config2);
1921                 if_print(size);
1922                 printed += sample_type__fprintf(fp, &first, evsel->attr.sample_type);
1923                 if (evsel->attr.read_format)
1924                         printed += read_format__fprintf(fp, &first, evsel->attr.read_format);
1925                 if_print(disabled);
1926                 if_print(inherit);
1927                 if_print(pinned);
1928                 if_print(exclusive);
1929                 if_print(exclude_user);
1930                 if_print(exclude_kernel);
1931                 if_print(exclude_hv);
1932                 if_print(exclude_idle);
1933                 if_print(mmap);
1934                 if_print(mmap2);
1935                 if_print(comm);
1936                 if_print(freq);
1937                 if_print(inherit_stat);
1938                 if_print(enable_on_exec);
1939                 if_print(task);
1940                 if_print(watermark);
1941                 if_print(precise_ip);
1942                 if_print(mmap_data);
1943                 if_print(sample_id_all);
1944                 if_print(exclude_host);
1945                 if_print(exclude_guest);
1946                 if_print(__reserved_1);
1947                 if_print(wakeup_events);
1948                 if_print(bp_type);
1949                 if_print(branch_sample_type);
1950         }
1951 out:
1952         fputc('\n', fp);
1953         return ++printed;
1954 }
1955
1956 bool perf_evsel__fallback(struct perf_evsel *evsel, int err,
1957                           char *msg, size_t msgsize)
1958 {
1959         if ((err == ENOENT || err == ENXIO || err == ENODEV) &&
1960             evsel->attr.type   == PERF_TYPE_HARDWARE &&
1961             evsel->attr.config == PERF_COUNT_HW_CPU_CYCLES) {
1962                 /*
1963                  * If it's cycles then fall back to hrtimer based
1964                  * cpu-clock-tick sw counter, which is always available even if
1965                  * no PMU support.
1966                  *
1967                  * PPC returns ENXIO until 2.6.37 (behavior changed with commit
1968                  * b0a873e).
1969                  */
1970                 scnprintf(msg, msgsize, "%s",
1971 "The cycles event is not supported, trying to fall back to cpu-clock-ticks");
1972
1973                 evsel->attr.type   = PERF_TYPE_SOFTWARE;
1974                 evsel->attr.config = PERF_COUNT_SW_CPU_CLOCK;
1975
1976                 free(evsel->name);
1977                 evsel->name = NULL;
1978                 return true;
1979         }
1980
1981         return false;
1982 }
1983
1984 int perf_evsel__open_strerror(struct perf_evsel *evsel,
1985                               struct perf_target *target,
1986                               int err, char *msg, size_t size)
1987 {
1988         switch (err) {
1989         case EPERM:
1990         case EACCES:
1991                 return scnprintf(msg, size,
1992                  "You may not have permission to collect %sstats.\n"
1993                  "Consider tweaking /proc/sys/kernel/perf_event_paranoid:\n"
1994                  " -1 - Not paranoid at all\n"
1995                  "  0 - Disallow raw tracepoint access for unpriv\n"
1996                  "  1 - Disallow cpu events for unpriv\n"
1997                  "  2 - Disallow kernel profiling for unpriv",
1998                                  target->system_wide ? "system-wide " : "");
1999         case ENOENT:
2000                 return scnprintf(msg, size, "The %s event is not supported.",
2001                                  perf_evsel__name(evsel));
2002         case EMFILE:
2003                 return scnprintf(msg, size, "%s",
2004                          "Too many events are opened.\n"
2005                          "Try again after reducing the number of events.");
2006         case ENODEV:
2007                 if (target->cpu_list)
2008                         return scnprintf(msg, size, "%s",
2009          "No such device - did you specify an out-of-range profile CPU?\n");
2010                 break;
2011         case EOPNOTSUPP:
2012                 if (evsel->attr.precise_ip)
2013                         return scnprintf(msg, size, "%s",
2014         "\'precise\' request may not be supported. Try removing 'p' modifier.");
2015 #if defined(__i386__) || defined(__x86_64__)
2016                 if (evsel->attr.type == PERF_TYPE_HARDWARE)
2017                         return scnprintf(msg, size, "%s",
2018         "No hardware sampling interrupt available.\n"
2019         "No APIC? If so then you can boot the kernel with the \"lapic\" boot parameter to force-enable it.");
2020 #endif
2021                 break;
2022         default:
2023                 break;
2024         }
2025
2026         return scnprintf(msg, size,
2027         "The sys_perf_event_open() syscall returned with %d (%s) for event (%s).  \n"
2028         "/bin/dmesg may provide additional information.\n"
2029         "No CONFIG_PERF_EVENTS=y kernel support configured?\n",
2030                          err, strerror(err), perf_evsel__name(evsel));
2031 }