tools/perf/util/evsel.c

   1 /*
   2  * Copyright (C) 2011, Red Hat Inc, Arnaldo Carvalho de Melo <[email protected]>
   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 <api/fs/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 #include "trace-event.h"
  27
  28 static struct {
  29         bool sample_id_all;
  30         bool exclude_guest;
  31         bool mmap2;
  32 } perf_missing_features;
  33
  34 #define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
  35
  36 int __perf_evsel__sample_size(u64 sample_type)
  37 {
  38         u64 mask = sample_type & PERF_SAMPLE_MASK;
  39         int size = 0;
  40         int i;
  41
  42         for (i = 0; i < 64; i++) {
  43                 if (mask & (1ULL << i))
  44                         size++;
  45         }
  46
  47         size *= sizeof(u64);
  48
  49         return size;
  50 }
  51
  52 /**
  53  * __perf_evsel__calc_id_pos - calculate id_pos.
  54  * @sample_type: sample type
  55  *
  56  * This function returns the position of the event id (PERF_SAMPLE_ID or
  57  * PERF_SAMPLE_IDENTIFIER) in a sample event i.e. in the array of struct
  58  * sample_event.
  59  */
  60 static int __perf_evsel__calc_id_pos(u64 sample_type)
  61 {
  62         int idx = 0;
  63
  64         if (sample_type & PERF_SAMPLE_IDENTIFIER)
  65                 return 0;
  66
  67         if (!(sample_type & PERF_SAMPLE_ID))
  68                 return -1;
  69
  70         if (sample_type & PERF_SAMPLE_IP)
  71                 idx += 1;
  72
  73         if (sample_type & PERF_SAMPLE_TID)
  74                 idx += 1;
  75
  76         if (sample_type & PERF_SAMPLE_TIME)
  77                 idx += 1;
  78
  79         if (sample_type & PERF_SAMPLE_ADDR)
  80                 idx += 1;
  81
  82         return idx;
  83 }
  84
  85 /**
  86  * __perf_evsel__calc_is_pos - calculate is_pos.
  87  * @sample_type: sample type
  88  *
  89  * This function returns the position (counting backwards) of the event id
  90  * (PERF_SAMPLE_ID or PERF_SAMPLE_IDENTIFIER) in a non-sample event i.e. if
  91  * sample_id_all is used there is an id sample appended to non-sample events.
  92  */
  93 static int __perf_evsel__calc_is_pos(u64 sample_type)
  94 {
  95         int idx = 1;
  96
  97         if (sample_type & PERF_SAMPLE_IDENTIFIER)
  98                 return 1;
  99
 100         if (!(sample_type & PERF_SAMPLE_ID))
 101                 return -1;
 102
 103         if (sample_type & PERF_SAMPLE_CPU)
 104                 idx += 1;
 105
 106         if (sample_type & PERF_SAMPLE_STREAM_ID)
 107                 idx += 1;
 108
 109         return idx;
 110 }
 111
 112 void perf_evsel__calc_id_pos(struct perf_evsel *evsel)
 113 {
 114         evsel->id_pos = __perf_evsel__calc_id_pos(evsel->attr.sample_type);
 115         evsel->is_pos = __perf_evsel__calc_is_pos(evsel->attr.sample_type);
 116 }
 117
 118 void hists__init(struct hists *hists)
 119 {
 120         memset(hists, 0, sizeof(*hists));
 121         hists->entries_in_array[0] = hists->entries_in_array[1] = RB_ROOT;
 122         hists->entries_in = &hists->entries_in_array[0];
 123         hists->entries_collapsed = RB_ROOT;
 124         hists->entries = RB_ROOT;
 125         pthread_mutex_init(&hists->lock, NULL);
 126 }
 127
 128 void __perf_evsel__set_sample_bit(struct perf_evsel *evsel,
 129                                   enum perf_event_sample_format bit)
 130 {
 131         if (!(evsel->attr.sample_type & bit)) {
 132                 evsel->attr.sample_type |= bit;
 133                 evsel->sample_size += sizeof(u64);
 134                 perf_evsel__calc_id_pos(evsel);
 135         }
 136 }
 137
 138 void __perf_evsel__reset_sample_bit(struct perf_evsel *evsel,
 139                                     enum perf_event_sample_format bit)
 140 {
 141         if (evsel->attr.sample_type & bit) {
 142                 evsel->attr.sample_type &= ~bit;
 143                 evsel->sample_size -= sizeof(u64);
 144                 perf_evsel__calc_id_pos(evsel);
 145         }
 146 }
 147
 148 void perf_evsel__set_sample_id(struct perf_evsel *evsel,
 149                                bool can_sample_identifier)
 150 {
 151         if (can_sample_identifier) {
 152                 perf_evsel__reset_sample_bit(evsel, ID);
 153                 perf_evsel__set_sample_bit(evsel, IDENTIFIER);
 154         } else {
 155                 perf_evsel__set_sample_bit(evsel, ID);
 156         }
 157         evsel->attr.read_format |= PERF_FORMAT_ID;
 158 }
 159
 160 void perf_evsel__init(struct perf_evsel *evsel,
 161                       struct perf_event_attr *attr, int idx)
 162 {
 163         evsel->idx         = idx;
 164         evsel->attr        = *attr;
 165         evsel->leader      = evsel;
 166         evsel->unit        = "";
 167         evsel->scale       = 1.0;
 168         INIT_LIST_HEAD(&evsel->node);
 169         hists__init(&evsel->hists);
 170         evsel->sample_size = __perf_evsel__sample_size(attr->sample_type);
 171         perf_evsel__calc_id_pos(evsel);
 172 }
 173
 174 struct perf_evsel *perf_evsel__new_idx(struct perf_event_attr *attr, int idx)
 175 {
 176         struct perf_evsel *evsel = zalloc(sizeof(*evsel));
 177
 178         if (evsel != NULL)
 179                 perf_evsel__init(evsel, attr, idx);
 180
 181         return evsel;
 182 }
 183
 184 struct perf_evsel *perf_evsel__newtp_idx(const char *sys, const char *name, int idx)
 185 {
 186         struct perf_evsel *evsel = zalloc(sizeof(*evsel));
 187
 188         if (evsel != NULL) {
 189                 struct perf_event_attr attr = {
 190                         .type          = PERF_TYPE_TRACEPOINT,
 191                         .sample_type   = (PERF_SAMPLE_RAW | PERF_SAMPLE_TIME |
 192                                           PERF_SAMPLE_CPU | PERF_SAMPLE_PERIOD),
 193                 };
 194
 195                 if (asprintf(&evsel->name, "%s:%s", sys, name) < 0)
 196                         goto out_free;
 197
 198                 evsel->tp_format = trace_event__tp_format(sys, name);
 199                 if (evsel->tp_format == NULL)
 200                         goto out_free;
 201
 202                 event_attr_init(&attr);
 203                 attr.config = evsel->tp_format->id;
 204                 attr.sample_period = 1;
 205                 perf_evsel__init(evsel, &attr, idx);
 206         }
 207
 208         return evsel;
 209
 210 out_free:
 211         zfree(&evsel->name);
 212         free(evsel);
 213         return NULL;
 214 }
 215
 216 const char *perf_evsel__hw_names[PERF_COUNT_HW_MAX] = {
 217         "cycles",
 218         "instructions",
 219         "cache-references",
 220         "cache-misses",
 221         "branches",
 222         "branch-misses",
 223         "bus-cycles",
 224         "stalled-cycles-frontend",
 225         "stalled-cycles-backend",
 226         "ref-cycles",
 227 };
 228
 229 static const char *__perf_evsel__hw_name(u64 config)
 230 {
 231         if (config < PERF_COUNT_HW_MAX && perf_evsel__hw_names[config])
 232                 return perf_evsel__hw_names[config];
 233
 234         return "unknown-hardware";
 235 }
 236
 237 static int perf_evsel__add_modifiers(struct perf_evsel *evsel, char *bf, size_t size)
 238 {
 239         int colon = 0, r = 0;
 240         struct perf_event_attr *attr = &evsel->attr;
 241         bool exclude_guest_default = false;
 242
 243 #define MOD_PRINT(context, mod) do {                                    \
 244                 if (!attr->exclude_##context) {                         \
 245                         if (!colon) colon = ++r;                        \
 246                         r += scnprintf(bf + r, size - r, "%c", mod);    \
 247                 } } while(0)
 248
 249         if (attr->exclude_kernel || attr->exclude_user || attr->exclude_hv) {
 250                 MOD_PRINT(kernel, 'k');
 251                 MOD_PRINT(user, 'u');
 252                 MOD_PRINT(hv, 'h');
 253                 exclude_guest_default = true;
 254         }
 255
 256         if (attr->precise_ip) {
 257                 if (!colon)
 258                         colon = ++r;
 259                 r += scnprintf(bf + r, size - r, "%.*s", attr->precise_ip, "ppp");
 260                 exclude_guest_default = true;
 261         }
 262
 263         if (attr->exclude_host || attr->exclude_guest == exclude_guest_default) {
 264                 MOD_PRINT(host, 'H');
 265                 MOD_PRINT(guest, 'G');
 266         }
 267 #undef MOD_PRINT
 268         if (colon)
 269                 bf[colon - 1] = ':';
 270         return r;
 271 }
 272
 273 static int perf_evsel__hw_name(struct perf_evsel *evsel, char *bf, size_t size)
 274 {
 275         int r = scnprintf(bf, size, "%s", __perf_evsel__hw_name(evsel->attr.config));
 276         return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
 277 }
 278
 279 const char *perf_evsel__sw_names[PERF_COUNT_SW_MAX] = {
 280         "cpu-clock",
 281         "task-clock",
 282         "page-faults",
 283         "context-switches",
 284         "cpu-migrations",
 285         "minor-faults",
 286         "major-faults",
 287         "alignment-faults",
 288         "emulation-faults",
 289         "dummy",
 290 };
 291
 292 static const char *__perf_evsel__sw_name(u64 config)
 293 {
 294         if (config < PERF_COUNT_SW_MAX && perf_evsel__sw_names[config])
 295                 return perf_evsel__sw_names[config];
 296         return "unknown-software";
 297 }
 298
 299 static int perf_evsel__sw_name(struct perf_evsel *evsel, char *bf, size_t size)
 300 {
 301         int r = scnprintf(bf, size, "%s", __perf_evsel__sw_name(evsel->attr.config));
 302         return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
 303 }
 304
 305 static int __perf_evsel__bp_name(char *bf, size_t size, u64 addr, u64 type)
 306 {
 307         int r;
 308
 309         r = scnprintf(bf, size, "mem:0x%" PRIx64 ":", addr);
 310
 311         if (type & HW_BREAKPOINT_R)
 312                 r += scnprintf(bf + r, size - r, "r");
 313
 314         if (type & HW_BREAKPOINT_W)
 315                 r += scnprintf(bf + r, size - r, "w");
 316
 317         if (type & HW_BREAKPOINT_X)
 318                 r += scnprintf(bf + r, size - r, "x");
 319
 320         return r;
 321 }
 322
 323 static int perf_evsel__bp_name(struct perf_evsel *evsel, char *bf, size_t size)
 324 {
 325         struct perf_event_attr *attr = &evsel->attr;
 326         int r = __perf_evsel__bp_name(bf, size, attr->bp_addr, attr->bp_type);
 327         return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
 328 }
 329
 330 const char *perf_evsel__hw_cache[PERF_COUNT_HW_CACHE_MAX]
 331                                 [PERF_EVSEL__MAX_ALIASES] = {
 332  { "L1-dcache", "l1-d",         "l1d",          "L1-data",              },
 333  { "L1-icache", "l1-i",         "l1i",          "L1-instruction",       },
 334  { "LLC",       "L2",                                                   },
 335  { "dTLB",      "d-tlb",        "Data-TLB",                             },
 336  { "iTLB",      "i-tlb",        "Instruction-TLB",                      },
 337  { "branch",    "branches",     "bpu",          "btb",          "bpc",  },
 338  { "node",                                                              },
 339 };
 340
 341 const char *perf_evsel__hw_cache_op[PERF_COUNT_HW_CACHE_OP_MAX]
 342                                    [PERF_EVSEL__MAX_ALIASES] = {
 343  { "load",      "loads",        "read",                                 },
 344  { "store",     "stores",       "write",                                },
 345  { "prefetch",  "prefetches",   "speculative-read", "speculative-load", },
 346 };
 347
 348 const char *perf_evsel__hw_cache_result[PERF_COUNT_HW_CACHE_RESULT_MAX]
 349                                        [PERF_EVSEL__MAX_ALIASES] = {
 350  { "refs",      "Reference",    "ops",          "access",               },
 351  { "misses",    "miss",                                                 },
 352 };
 353
 354 #define C(x)            PERF_COUNT_HW_CACHE_##x
 355 #define CACHE_READ      (1 << C(OP_READ))
 356 #define CACHE_WRITE     (1 << C(OP_WRITE))
 357 #define CACHE_PREFETCH  (1 << C(OP_PREFETCH))
 358 #define COP(x)          (1 << x)
 359
 360 /*
 361  * cache operartion stat
 362  * L1I : Read and prefetch only
 363  * ITLB and BPU : Read-only
 364  */
 365 static unsigned long perf_evsel__hw_cache_stat[C(MAX)] = {
 366  [C(L1D)]       = (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 367  [C(L1I)]       = (CACHE_READ | CACHE_PREFETCH),
 368  [C(LL)]        = (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 369  [C(DTLB)]      = (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 370  [C(ITLB)]      = (CACHE_READ),
 371  [C(BPU)]       = (CACHE_READ),
 372  [C(NODE)]      = (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 373 };
 374
 375 bool perf_evsel__is_cache_op_valid(u8 type, u8 op)
 376 {
 377         if (perf_evsel__hw_cache_stat[type] & COP(op))
 378                 return true;    /* valid */
 379         else
 380                 return false;   /* invalid */
 381 }
 382
 383 int __perf_evsel__hw_cache_type_op_res_name(u8 type, u8 op, u8 result,
 384                                             char *bf, size_t size)
 385 {
 386         if (result) {
 387                 return scnprintf(bf, size, "%s-%s-%s", perf_evsel__hw_cache[type][0],
 388                                  perf_evsel__hw_cache_op[op][0],
 389                                  perf_evsel__hw_cache_result[result][0]);
 390         }
 391
 392         return scnprintf(bf, size, "%s-%s", perf_evsel__hw_cache[type][0],
 393                          perf_evsel__hw_cache_op[op][1]);
 394 }
 395
 396 static int __perf_evsel__hw_cache_name(u64 config, char *bf, size_t size)
 397 {
 398         u8 op, result, type = (config >>  0) & 0xff;
 399         const char *err = "unknown-ext-hardware-cache-type";
 400
 401         if (type > PERF_COUNT_HW_CACHE_MAX)
 402                 goto out_err;
 403
 404         op = (config >>  8) & 0xff;
 405         err = "unknown-ext-hardware-cache-op";
 406         if (op > PERF_COUNT_HW_CACHE_OP_MAX)
 407                 goto out_err;
 408
 409         result = (config >> 16) & 0xff;
 410         err = "unknown-ext-hardware-cache-result";
 411         if (result > PERF_COUNT_HW_CACHE_RESULT_MAX)
 412                 goto out_err;
 413
 414         err = "invalid-cache";
 415         if (!perf_evsel__is_cache_op_valid(type, op))
 416                 goto out_err;
 417
 418         return __perf_evsel__hw_cache_type_op_res_name(type, op, result, bf, size);
 419 out_err:
 420         return scnprintf(bf, size, "%s", err);
 421 }
 422
 423 static int perf_evsel__hw_cache_name(struct perf_evsel *evsel, char *bf, size_t size)
 424 {
 425         int ret = __perf_evsel__hw_cache_name(evsel->attr.config, bf, size);
 426         return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
 427 }
 428
 429 static int perf_evsel__raw_name(struct perf_evsel *evsel, char *bf, size_t size)
 430 {
 431         int ret = scnprintf(bf, size, "raw 0x%" PRIx64, evsel->attr.config);
 432         return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
 433 }
 434
 435 const char *perf_evsel__name(struct perf_evsel *evsel)
 436 {
 437         char bf[128];
 438
 439         if (evsel->name)
 440                 return evsel->name;
 441
 442         switch (evsel->attr.type) {
 443         case PERF_TYPE_RAW:
 444                 perf_evsel__raw_name(evsel, bf, sizeof(bf));
 445                 break;
 446
 447         case PERF_TYPE_HARDWARE:
 448                 perf_evsel__hw_name(evsel, bf, sizeof(bf));
 449                 break;
 450
 451         case PERF_TYPE_HW_CACHE:
 452                 perf_evsel__hw_cache_name(evsel, bf, sizeof(bf));
 453                 break;
 454
 455         case PERF_TYPE_SOFTWARE:
 456                 perf_evsel__sw_name(evsel, bf, sizeof(bf));
 457                 break;
 458
 459         case PERF_TYPE_TRACEPOINT:
 460                 scnprintf(bf, sizeof(bf), "%s", "unknown tracepoint");
 461                 break;
 462
 463         case PERF_TYPE_BREAKPOINT:
 464                 perf_evsel__bp_name(evsel, bf, sizeof(bf));
 465                 break;
 466
 467         default:
 468                 scnprintf(bf, sizeof(bf), "unknown attr type: %d",
 469                           evsel->attr.type);
 470                 break;
 471         }
 472
 473         evsel->name = strdup(bf);
 474
 475         return evsel->name ?: "unknown";
 476 }
 477
 478 const char *perf_evsel__group_name(struct perf_evsel *evsel)
 479 {
 480         return evsel->group_name ?: "anon group";
 481 }
 482
 483 int perf_evsel__group_desc(struct perf_evsel *evsel, char *buf, size_t size)
 484 {
 485         int ret;
 486         struct perf_evsel *pos;
 487         const char *group_name = perf_evsel__group_name(evsel);
 488
 489         ret = scnprintf(buf, size, "%s", group_name);
 490
 491         ret += scnprintf(buf + ret, size - ret, " { %s",
 492                          perf_evsel__name(evsel));
 493
 494         for_each_group_member(pos, evsel)
 495                 ret += scnprintf(buf + ret, size - ret, ", %s",
 496                                  perf_evsel__name(pos));
 497
 498         ret += scnprintf(buf + ret, size - ret, " }");
 499
 500         return ret;
 501 }
 502
 503 /*
 504  * The enable_on_exec/disabled value strategy:
 505  *
 506  *  1) For any type of traced program:
 507  *    - all independent events and group leaders are disabled
 508  *    - all group members are enabled
 509  *
 510  *     Group members are ruled by group leaders. They need to
 511  *     be enabled, because the group scheduling relies on that.
 512  *
 513  *  2) For traced programs executed by perf:
 514  *     - all independent events and group leaders have
 515  *       enable_on_exec set
 516  *     - we don't specifically enable or disable any event during
 517  *       the record command
 518  *
 519  *     Independent events and group leaders are initially disabled
 520  *     and get enabled by exec. Group members are ruled by group
 521  *     leaders as stated in 1).
 522  *
 523  *  3) For traced programs attached by perf (pid/tid):
 524  *     - we specifically enable or disable all events during
 525  *       the record command
 526  *
 527  *     When attaching events to already running traced we
 528  *     enable/disable events specifically, as there's no
 529  *     initial traced exec call.
 530  */
 531 void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts)
 532 {
 533         struct perf_evsel *leader = evsel->leader;
 534         struct perf_event_attr *attr = &evsel->attr;
 535         int track = !evsel->idx; /* only the first counter needs these */
 536         bool per_cpu = opts->target.default_per_cpu && !opts->target.per_thread;
 537
 538         attr->sample_id_all = perf_missing_features.sample_id_all ? 0 : 1;
 539         attr->inherit       = !opts->no_inherit;
 540
 541         perf_evsel__set_sample_bit(evsel, IP);
 542         perf_evsel__set_sample_bit(evsel, TID);
 543
 544         if (evsel->sample_read) {
 545                 perf_evsel__set_sample_bit(evsel, READ);
 546
 547                 /*
 548                  * We need ID even in case of single event, because
 549                  * PERF_SAMPLE_READ process ID specific data.
 550                  */
 551                 perf_evsel__set_sample_id(evsel, false);
 552
 553                 /*
 554                  * Apply group format only if we belong to group
 555                  * with more than one members.
 556                  */
 557                 if (leader->nr_members > 1) {
 558                         attr->read_format |= PERF_FORMAT_GROUP;
 559                         attr->inherit = 0;
 560                 }
 561         }
 562
 563         /*
 564          * We default some events to a 1 default interval. But keep
 565          * it a weak assumption overridable by the user.
 566          */
 567         if (!attr->sample_period || (opts->user_freq != UINT_MAX &&
 568                                      opts->user_interval != ULLONG_MAX)) {
 569                 if (opts->freq) {
 570                         perf_evsel__set_sample_bit(evsel, PERIOD);
 571                         attr->freq              = 1;
 572                         attr->sample_freq       = opts->freq;
 573                 } else {
 574                         attr->sample_period = opts->default_interval;
 575                 }
 576         }
 577
 578         /*
 579          * Disable sampling for all group members other
 580          * than leader in case leader 'leads' the sampling.
 581          */
 582         if ((leader != evsel) && leader->sample_read) {
 583                 attr->sample_freq   = 0;
 584                 attr->sample_period = 0;
 585         }
 586
 587         if (opts->no_samples)
 588                 attr->sample_freq = 0;
 589
 590         if (opts->inherit_stat)
 591                 attr->inherit_stat = 1;
 592
 593         if (opts->sample_address) {
 594                 perf_evsel__set_sample_bit(evsel, ADDR);
 595                 attr->mmap_data = track;
 596         }
 597
 598         if (opts->call_graph) {
 599                 perf_evsel__set_sample_bit(evsel, CALLCHAIN);
 600
 601                 if (opts->call_graph == CALLCHAIN_DWARF) {
 602                         perf_evsel__set_sample_bit(evsel, REGS_USER);
 603                         perf_evsel__set_sample_bit(evsel, STACK_USER);
 604                         attr->sample_regs_user = PERF_REGS_MASK;
 605                         attr->sample_stack_user = opts->stack_dump_size;
 606                         attr->exclude_callchain_user = 1;
 607                 }
 608         }
 609
 610         if (target__has_cpu(&opts->target))
 611                 perf_evsel__set_sample_bit(evsel, CPU);
 612
 613         if (opts->period)
 614                 perf_evsel__set_sample_bit(evsel, PERIOD);
 615
 616         if (!perf_missing_features.sample_id_all &&
 617             (opts->sample_time || !opts->no_inherit ||
 618              target__has_cpu(&opts->target) || per_cpu))
 619                 perf_evsel__set_sample_bit(evsel, TIME);
 620
 621         if (opts->raw_samples) {
 622                 perf_evsel__set_sample_bit(evsel, TIME);
 623                 perf_evsel__set_sample_bit(evsel, RAW);
 624                 perf_evsel__set_sample_bit(evsel, CPU);
 625         }
 626
 627         if (opts->sample_address)
 628                 perf_evsel__set_sample_bit(evsel, DATA_SRC);
 629
 630         if (opts->no_delay) {
 631                 attr->watermark = 0;
 632                 attr->wakeup_events = 1;
 633         }
 634         if (opts->branch_stack) {
 635                 perf_evsel__set_sample_bit(evsel, BRANCH_STACK);
 636                 attr->branch_sample_type = opts->branch_stack;
 637         }
 638
 639         if (opts->sample_weight)
 640                 perf_evsel__set_sample_bit(evsel, WEIGHT);
 641
 642         attr->mmap  = track;
 643         attr->comm  = track;
 644
 645         if (opts->sample_transaction)
 646                 perf_evsel__set_sample_bit(evsel, TRANSACTION);
 647
 648         /*
 649          * XXX see the function comment above
 650          *
 651          * Disabling only independent events or group leaders,
 652          * keeping group members enabled.
 653          */
 654         if (perf_evsel__is_group_leader(evsel))
 655                 attr->disabled = 1;
 656
 657         /*
 658          * Setting enable_on_exec for independent events and
 659          * group leaders for traced executed by perf.
 660          */
 661         if (target__none(&opts->target) && perf_evsel__is_group_leader(evsel))
 662                 attr->enable_on_exec = 1;
 663 }
 664
 665 int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
 666 {
 667         int cpu, thread;
 668         evsel->fd = xyarray__new(ncpus, nthreads, sizeof(int));
 669
 670         if (evsel->fd) {
 671                 for (cpu = 0; cpu < ncpus; cpu++) {
 672                         for (thread = 0; thread < nthreads; thread++) {
 673                                 FD(evsel, cpu, thread) = -1;
 674                         }
 675                 }
 676         }
 677
 678         return evsel->fd != NULL ? 0 : -ENOMEM;
 679 }
 680
 681 static int perf_evsel__run_ioctl(struct perf_evsel *evsel, int ncpus, int nthreads,
 682                           int ioc,  void *arg)
 683 {
 684         int cpu, thread;
 685
 686         for (cpu = 0; cpu < ncpus; cpu++) {
 687                 for (thread = 0; thread < nthreads; thread++) {
 688                         int fd = FD(evsel, cpu, thread),
 689                             err = ioctl(fd, ioc, arg);
 690
 691                         if (err)
 692                                 return err;
 693                 }
 694         }
 695
 696         return 0;
 697 }
 698
 699 int perf_evsel__set_filter(struct perf_evsel *evsel, int ncpus, int nthreads,
 700                            const char *filter)
 701 {
 702         return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
 703                                      PERF_EVENT_IOC_SET_FILTER,
 704                                      (void *)filter);
 705 }
 706
 707 int perf_evsel__enable(struct perf_evsel *evsel, int ncpus, int nthreads)
 708 {
 709         return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
 710                                      PERF_EVENT_IOC_ENABLE,
 711                                      0);
 712 }
 713
 714 int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
 715 {
 716         evsel->sample_id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
 717         if (evsel->sample_id == NULL)
 718                 return -ENOMEM;
 719
 720         evsel->id = zalloc(ncpus * nthreads * sizeof(u64));
 721         if (evsel->id == NULL) {
 722                 xyarray__delete(evsel->sample_id);
 723                 evsel->sample_id = NULL;
 724                 return -ENOMEM;
 725         }
 726
 727         return 0;
 728 }
 729
 730 void perf_evsel__reset_counts(struct perf_evsel *evsel, int ncpus)
 731 {
 732         memset(evsel->counts, 0, (sizeof(*evsel->counts) +
 733                                  (ncpus * sizeof(struct perf_counts_values))));
 734 }
 735
 736 int perf_evsel__alloc_counts(struct perf_evsel *evsel, int ncpus)
 737 {
 738         evsel->counts = zalloc((sizeof(*evsel->counts) +
 739                                 (ncpus * sizeof(struct perf_counts_values))));
 740         return evsel->counts != NULL ? 0 : -ENOMEM;
 741 }
 742
 743 void perf_evsel__free_fd(struct perf_evsel *evsel)
 744 {
 745         xyarray__delete(evsel->fd);
 746         evsel->fd = NULL;
 747 }
 748
 749 void perf_evsel__free_id(struct perf_evsel *evsel)
 750 {
 751         xyarray__delete(evsel->sample_id);
 752         evsel->sample_id = NULL;
 753         zfree(&evsel->id);
 754 }
 755
 756 void perf_evsel__close_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
 757 {
 758         int cpu, thread;
 759
 760         for (cpu = 0; cpu < ncpus; cpu++)
 761                 for (thread = 0; thread < nthreads; ++thread) {
 762                         close(FD(evsel, cpu, thread));
 763                         FD(evsel, cpu, thread) = -1;
 764                 }
 765 }
 766
 767 void perf_evsel__free_counts(struct perf_evsel *evsel)
 768 {
 769         zfree(&evsel->counts);
 770 }
 771
 772 void perf_evsel__exit(struct perf_evsel *evsel)
 773 {
 774         assert(list_empty(&evsel->node));
 775         perf_evsel__free_fd(evsel);
 776         perf_evsel__free_id(evsel);
 777 }
 778
 779 void perf_evsel__delete(struct perf_evsel *evsel)
 780 {
 781         perf_evsel__exit(evsel);
 782         close_cgroup(evsel->cgrp);
 783         zfree(&evsel->group_name);
 784         if (evsel->tp_format)
 785                 pevent_free_format(evsel->tp_format);
 786         zfree(&evsel->name);
 787         free(evsel);
 788 }
 789
 790 static inline void compute_deltas(struct perf_evsel *evsel,
 791                                   int cpu,
 792                                   struct perf_counts_values *count)
 793 {
 794         struct perf_counts_values tmp;
 795
 796         if (!evsel->prev_raw_counts)
 797                 return;
 798
 799         if (cpu == -1) {
 800                 tmp = evsel->prev_raw_counts->aggr;
 801                 evsel->prev_raw_counts->aggr = *count;
 802         } else {
 803                 tmp = evsel->prev_raw_counts->cpu[cpu];
 804                 evsel->prev_raw_counts->cpu[cpu] = *count;
 805         }
 806
 807         count->val = count->val - tmp.val;
 808         count->ena = count->ena - tmp.ena;
 809         count->run = count->run - tmp.run;
 810 }
 811
 812 int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
 813                               int cpu, int thread, bool scale)
 814 {
 815         struct perf_counts_values count;
 816         size_t nv = scale ? 3 : 1;
 817
 818         if (FD(evsel, cpu, thread) < 0)
 819                 return -EINVAL;
 820
 821         if (evsel->counts == NULL && perf_evsel__alloc_counts(evsel, cpu + 1) < 0)
 822                 return -ENOMEM;
 823
 824         if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) < 0)
 825                 return -errno;
 826
 827         compute_deltas(evsel, cpu, &count);
 828
 829         if (scale) {
 830                 if (count.run == 0)
 831                         count.val = 0;
 832                 else if (count.run < count.ena)
 833                         count.val = (u64)((double)count.val * count.ena / count.run + 0.5);
 834         } else
 835                 count.ena = count.run = 0;
 836
 837         evsel->counts->cpu[cpu] = count;
 838         return 0;
 839 }
 840
 841 int __perf_evsel__read(struct perf_evsel *evsel,
 842                        int ncpus, int nthreads, bool scale)
 843 {
 844         size_t nv = scale ? 3 : 1;
 845         int cpu, thread;
 846         struct perf_counts_values *aggr = &evsel->counts->aggr, count;
 847
 848         aggr->val = aggr->ena = aggr->run = 0;
 849
 850         for (cpu = 0; cpu < ncpus; cpu++) {
 851                 for (thread = 0; thread < nthreads; thread++) {
 852                         if (FD(evsel, cpu, thread) < 0)
 853                                 continue;
 854
 855                         if (readn(FD(evsel, cpu, thread),
 856                                   &count, nv * sizeof(u64)) < 0)
 857                                 return -errno;
 858
 859                         aggr->val += count.val;
 860                         if (scale) {
 861                                 aggr->ena += count.ena;
 862                                 aggr->run += count.run;
 863                         }
 864                 }
 865         }
 866
 867         compute_deltas(evsel, -1, aggr);
 868
 869         evsel->counts->scaled = 0;
 870         if (scale) {
 871                 if (aggr->run == 0) {
 872                         evsel->counts->scaled = -1;
 873                         aggr->val = 0;
 874                         return 0;
 875                 }
 876
 877                 if (aggr->run < aggr->ena) {
 878                         evsel->counts->scaled = 1;
 879                         aggr->val = (u64)((double)aggr->val * aggr->ena / aggr->run + 0.5);
 880                 }
 881         } else
 882                 aggr->ena = aggr->run = 0;
 883
 884         return 0;
 885 }
 886
 887 static int get_group_fd(struct perf_evsel *evsel, int cpu, int thread)
 888 {
 889         struct perf_evsel *leader = evsel->leader;
 890         int fd;
 891
 892         if (perf_evsel__is_group_leader(evsel))
 893                 return -1;
 894
 895         /*
 896          * Leader must be already processed/open,
 897          * if not it's a bug.
 898          */
 899         BUG_ON(!leader->fd);
 900
 901         fd = FD(leader, cpu, thread);
 902         BUG_ON(fd == -1);
 903
 904         return fd;
 905 }
 906
 907 #define __PRINT_ATTR(fmt, cast, field)  \
 908         fprintf(fp, "  %-19s "fmt"\n", #field, cast attr->field)
 909
 910 #define PRINT_ATTR_U32(field)  __PRINT_ATTR("%u" , , field)
 911 #define PRINT_ATTR_X32(field)  __PRINT_ATTR("%#x", , field)
 912 #define PRINT_ATTR_U64(field)  __PRINT_ATTR("%" PRIu64, (uint64_t), field)
 913 #define PRINT_ATTR_X64(field)  __PRINT_ATTR("%#"PRIx64, (uint64_t), field)
 914
 915 #define PRINT_ATTR2N(name1, field1, name2, field2)      \
 916         fprintf(fp, "  %-19s %u    %-19s %u\n",         \
 917         name1, attr->field1, name2, attr->field2)
 918
 919 #define PRINT_ATTR2(field1, field2) \
 920         PRINT_ATTR2N(#field1, field1, #field2, field2)
 921
 922 static size_t perf_event_attr__fprintf(struct perf_event_attr *attr, FILE *fp)
 923 {
 924         size_t ret = 0;
 925
 926         ret += fprintf(fp, "%.60s\n", graph_dotted_line);
 927         ret += fprintf(fp, "perf_event_attr:\n");
 928
 929         ret += PRINT_ATTR_U32(type);
 930         ret += PRINT_ATTR_U32(size);
 931         ret += PRINT_ATTR_X64(config);
 932         ret += PRINT_ATTR_U64(sample_period);
 933         ret += PRINT_ATTR_U64(sample_freq);
 934         ret += PRINT_ATTR_X64(sample_type);
 935         ret += PRINT_ATTR_X64(read_format);
 936
 937         ret += PRINT_ATTR2(disabled, inherit);
 938         ret += PRINT_ATTR2(pinned, exclusive);
 939         ret += PRINT_ATTR2(exclude_user, exclude_kernel);
 940         ret += PRINT_ATTR2(exclude_hv, exclude_idle);
 941         ret += PRINT_ATTR2(mmap, comm);
 942         ret += PRINT_ATTR2(freq, inherit_stat);
 943         ret += PRINT_ATTR2(enable_on_exec, task);
 944         ret += PRINT_ATTR2(watermark, precise_ip);
 945         ret += PRINT_ATTR2(mmap_data, sample_id_all);
 946         ret += PRINT_ATTR2(exclude_host, exclude_guest);
 947         ret += PRINT_ATTR2N("excl.callchain_kern", exclude_callchain_kernel,
 948                             "excl.callchain_user", exclude_callchain_user);
 949         ret += PRINT_ATTR_U32(mmap2);
 950
 951         ret += PRINT_ATTR_U32(wakeup_events);
 952         ret += PRINT_ATTR_U32(wakeup_watermark);
 953         ret += PRINT_ATTR_X32(bp_type);
 954         ret += PRINT_ATTR_X64(bp_addr);
 955         ret += PRINT_ATTR_X64(config1);
 956         ret += PRINT_ATTR_U64(bp_len);
 957         ret += PRINT_ATTR_X64(config2);
 958         ret += PRINT_ATTR_X64(branch_sample_type);
 959         ret += PRINT_ATTR_X64(sample_regs_user);
 960         ret += PRINT_ATTR_U32(sample_stack_user);
 961
 962         ret += fprintf(fp, "%.60s\n", graph_dotted_line);
 963
 964         return ret;
 965 }
 966
 967 static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
 968                               struct thread_map *threads)
 969 {
 970         int cpu, thread;
 971         unsigned long flags = 0;
 972         int pid = -1, err;
 973         enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;
 974
 975         if (evsel->fd == NULL &&
 976             perf_evsel__alloc_fd(evsel, cpus->nr, threads->nr) < 0)
 977                 return -ENOMEM;
 978
 979         if (evsel->cgrp) {
 980                 flags = PERF_FLAG_PID_CGROUP;
 981                 pid = evsel->cgrp->fd;
 982         }
 983
 984 fallback_missing_features:
 985         if (perf_missing_features.mmap2)
 986                 evsel->attr.mmap2 = 0;
 987         if (perf_missing_features.exclude_guest)
 988                 evsel->attr.exclude_guest = evsel->attr.exclude_host = 0;
 989 retry_sample_id:
 990         if (perf_missing_features.sample_id_all)
 991                 evsel->attr.sample_id_all = 0;
 992
 993         if (verbose >= 2)
 994                 perf_event_attr__fprintf(&evsel->attr, stderr);
 995
 996         for (cpu = 0; cpu < cpus->nr; cpu++) {
 997
 998                 for (thread = 0; thread < threads->nr; thread++) {
 999                         int group_fd;
1000
1001                         if (!evsel->cgrp)
1002                                 pid = threads->map[thread];
1003
1004                         group_fd = get_group_fd(evsel, cpu, thread);
1005 retry_open:
1006                         pr_debug2("perf_event_open: pid %d  cpu %d  group_fd %d  flags %#lx\n",
1007                                   pid, cpus->map[cpu], group_fd, flags);
1008
1009                         FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr,
1010                                                                      pid,
1011                                                                      cpus->map[cpu],
1012                                                                      group_fd, flags);
1013                         if (FD(evsel, cpu, thread) < 0) {
1014                                 err = -errno;
1015                                 pr_debug2("perf_event_open failed, error %d\n",
1016                                           err);
1017                                 goto try_fallback;
1018                         }
1019                         set_rlimit = NO_CHANGE;
1020                 }
1021         }
1022
1023         return 0;
1024
1025 try_fallback:
1026         /*
1027          * perf stat needs between 5 and 22 fds per CPU. When we run out
1028          * of them try to increase the limits.
1029          */
1030         if (err == -EMFILE && set_rlimit < INCREASED_MAX) {
1031                 struct rlimit l;
1032                 int old_errno = errno;
1033
1034                 if (getrlimit(RLIMIT_NOFILE, &l) == 0) {
1035                         if (set_rlimit == NO_CHANGE)
1036                                 l.rlim_cur = l.rlim_max;
1037                         else {
1038                                 l.rlim_cur = l.rlim_max + 1000;
1039                                 l.rlim_max = l.rlim_cur;
1040                         }
1041                         if (setrlimit(RLIMIT_NOFILE, &l) == 0) {
1042                                 set_rlimit++;
1043                                 errno = old_errno;
1044                                 goto retry_open;
1045                         }
1046                 }
1047                 errno = old_errno;
1048         }
1049
1050         if (err != -EINVAL || cpu > 0 || thread > 0)
1051                 goto out_close;
1052
1053         if (!perf_missing_features.mmap2 && evsel->attr.mmap2) {
1054                 perf_missing_features.mmap2 = true;
1055                 goto fallback_missing_features;
1056         } else if (!perf_missing_features.exclude_guest &&
1057                    (evsel->attr.exclude_guest || evsel->attr.exclude_host)) {
1058                 perf_missing_features.exclude_guest = true;
1059                 goto fallback_missing_features;
1060         } else if (!perf_missing_features.sample_id_all) {
1061                 perf_missing_features.sample_id_all = true;
1062                 goto retry_sample_id;
1063         }
1064
1065 out_close:
1066         do {
1067                 while (--thread >= 0) {
1068                         close(FD(evsel, cpu, thread));
1069                         FD(evsel, cpu, thread) = -1;
1070                 }
1071                 thread = threads->nr;
1072         } while (--cpu >= 0);
1073         return err;
1074 }
1075
1076 void perf_evsel__close(struct perf_evsel *evsel, int ncpus, int nthreads)
1077 {
1078         if (evsel->fd == NULL)
1079                 return;
1080
1081         perf_evsel__close_fd(evsel, ncpus, nthreads);
1082         perf_evsel__free_fd(evsel);
1083         evsel->fd = NULL;
1084 }
1085
1086 static struct {
1087         struct cpu_map map;
1088         int cpus[1];
1089 } empty_cpu_map = {
1090         .map.nr = 1,
1091         .cpus   = { -1, },
1092 };
1093
1094 static struct {
1095         struct thread_map map;
1096         int threads[1];
1097 } empty_thread_map = {
1098         .map.nr  = 1,
1099         .threads = { -1, },
1100 };
1101
1102 int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1103                      struct thread_map *threads)
1104 {
1105         if (cpus == NULL) {
1106                 /* Work around old compiler warnings about strict aliasing */
1107                 cpus = &empty_cpu_map.map;
1108         }
1109
1110         if (threads == NULL)
1111                 threads = &empty_thread_map.map;
1112
1113         return __perf_evsel__open(evsel, cpus, threads);
1114 }
1115
1116 int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
1117                              struct cpu_map *cpus)
1118 {
1119         return __perf_evsel__open(evsel, cpus, &empty_thread_map.map);
1120 }
1121
1122 int perf_evsel__open_per_thread(struct perf_evsel *evsel,
1123                                 struct thread_map *threads)
1124 {
1125         return __perf_evsel__open(evsel, &empty_cpu_map.map, threads);
1126 }
1127
1128 static int perf_evsel__parse_id_sample(const struct perf_evsel *evsel,
1129                                        const union perf_event *event,
1130                                        struct perf_sample *sample)
1131 {
1132         u64 type = evsel->attr.sample_type;
1133         const u64 *array = event->sample.array;
1134         bool swapped = evsel->needs_swap;
1135         union u64_swap u;
1136
1137         array += ((event->header.size -
1138                    sizeof(event->header)) / sizeof(u64)) - 1;
1139
1140         if (type & PERF_SAMPLE_IDENTIFIER) {
1141                 sample->id = *array;
1142                 array--;
1143         }
1144
1145         if (type & PERF_SAMPLE_CPU) {
1146                 u.val64 = *array;
1147                 if (swapped) {
1148                         /* undo swap of u64, then swap on individual u32s */
1149                         u.val64 = bswap_64(u.val64);
1150                         u.val32[0] = bswap_32(u.val32[0]);
1151                 }
1152
1153                 sample->cpu = u.val32[0];
1154                 array--;
1155         }
1156
1157         if (type & PERF_SAMPLE_STREAM_ID) {
1158                 sample->stream_id = *array;
1159                 array--;
1160         }
1161
1162         if (type & PERF_SAMPLE_ID) {
1163                 sample->id = *array;
1164                 array--;
1165         }
1166
1167         if (type & PERF_SAMPLE_TIME) {
1168                 sample->time = *array;
1169                 array--;
1170         }
1171
1172         if (type & PERF_SAMPLE_TID) {
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                         u.val32[1] = bswap_32(u.val32[1]);
1179                 }
1180
1181                 sample->pid = u.val32[0];
1182                 sample->tid = u.val32[1];
1183                 array--;
1184         }
1185
1186         return 0;
1187 }
1188
1189 static inline bool overflow(const void *endp, u16 max_size, const void *offset,
1190                             u64 size)
1191 {
1192         return size > max_size || offset + size > endp;
1193 }
1194
1195 #define OVERFLOW_CHECK(offset, size, max_size)                          \
1196         do {                                                            \
1197                 if (overflow(endp, (max_size), (offset), (size)))       \
1198                         return -EFAULT;                                 \
1199         } while (0)
1200
1201 #define OVERFLOW_CHECK_u64(offset) \
1202         OVERFLOW_CHECK(offset, sizeof(u64), sizeof(u64))
1203
1204 int perf_evsel__parse_sample(struct perf_evsel *evsel, union perf_event *event,
1205                              struct perf_sample *data)
1206 {
1207         u64 type = evsel->attr.sample_type;
1208         bool swapped = evsel->needs_swap;
1209         const u64 *array;
1210         u16 max_size = event->header.size;
1211         const void *endp = (void *)event + max_size;
1212         u64 sz;
1213
1214         /*
1215          * used for cross-endian analysis. See git commit 65014ab3
1216          * for why this goofiness is needed.
1217          */
1218         union u64_swap u;
1219
1220         memset(data, 0, sizeof(*data));
1221         data->cpu = data->pid = data->tid = -1;
1222         data->stream_id = data->id = data->time = -1ULL;
1223         data->period = 1;
1224         data->weight = 0;
1225
1226         if (event->header.type != PERF_RECORD_SAMPLE) {
1227                 if (!evsel->attr.sample_id_all)
1228                         return 0;
1229                 return perf_evsel__parse_id_sample(evsel, event, data);
1230         }
1231
1232         array = event->sample.array;
1233
1234         /*
1235          * The evsel's sample_size is based on PERF_SAMPLE_MASK which includes
1236          * up to PERF_SAMPLE_PERIOD.  After that overflow() must be used to
1237          * check the format does not go past the end of the event.
1238          */
1239         if (evsel->sample_size + sizeof(event->header) > event->header.size)
1240                 return -EFAULT;
1241
1242         data->id = -1ULL;
1243         if (type & PERF_SAMPLE_IDENTIFIER) {
1244                 data->id = *array;
1245                 array++;
1246         }
1247
1248         if (type & PERF_SAMPLE_IP) {
1249                 data->ip = *array;
1250                 array++;
1251         }
1252
1253         if (type & PERF_SAMPLE_TID) {
1254                 u.val64 = *array;
1255                 if (swapped) {
1256                         /* undo swap of u64, then swap on individual u32s */
1257                         u.val64 = bswap_64(u.val64);
1258                         u.val32[0] = bswap_32(u.val32[0]);
1259                         u.val32[1] = bswap_32(u.val32[1]);
1260                 }
1261
1262                 data->pid = u.val32[0];
1263                 data->tid = u.val32[1];
1264                 array++;
1265         }
1266
1267         if (type & PERF_SAMPLE_TIME) {
1268                 data->time = *array;
1269                 array++;
1270         }
1271
1272         data->addr = 0;
1273         if (type & PERF_SAMPLE_ADDR) {
1274                 data->addr = *array;
1275                 array++;
1276         }
1277
1278         if (type & PERF_SAMPLE_ID) {
1279                 data->id = *array;
1280                 array++;
1281         }
1282
1283         if (type & PERF_SAMPLE_STREAM_ID) {
1284                 data->stream_id = *array;
1285                 array++;
1286         }
1287
1288         if (type & PERF_SAMPLE_CPU) {
1289
1290                 u.val64 = *array;
1291                 if (swapped) {
1292                         /* undo swap of u64, then swap on individual u32s */
1293                         u.val64 = bswap_64(u.val64);
1294                         u.val32[0] = bswap_32(u.val32[0]);
1295                 }
1296
1297                 data->cpu = u.val32[0];
1298                 array++;
1299         }
1300
1301         if (type & PERF_SAMPLE_PERIOD) {
1302                 data->period = *array;
1303                 array++;
1304         }
1305
1306         if (type & PERF_SAMPLE_READ) {
1307                 u64 read_format = evsel->attr.read_format;
1308
1309                 OVERFLOW_CHECK_u64(array);
1310                 if (read_format & PERF_FORMAT_GROUP)
1311                         data->read.group.nr = *array;
1312                 else
1313                         data->read.one.value = *array;
1314
1315                 array++;
1316
1317                 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1318                         OVERFLOW_CHECK_u64(array);
1319                         data->read.time_enabled = *array;
1320                         array++;
1321                 }
1322
1323                 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1324                         OVERFLOW_CHECK_u64(array);
1325                         data->read.time_running = *array;
1326                         array++;
1327                 }
1328
1329                 /* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1330                 if (read_format & PERF_FORMAT_GROUP) {
1331                         const u64 max_group_nr = UINT64_MAX /
1332                                         sizeof(struct sample_read_value);
1333
1334                         if (data->read.group.nr > max_group_nr)
1335                                 return -EFAULT;
1336                         sz = data->read.group.nr *
1337                              sizeof(struct sample_read_value);
1338                         OVERFLOW_CHECK(array, sz, max_size);
1339                         data->read.group.values =
1340                                         (struct sample_read_value *)array;
1341                         array = (void *)array + sz;
1342                 } else {
1343                         OVERFLOW_CHECK_u64(array);
1344                         data->read.one.id = *array;
1345                         array++;
1346                 }
1347         }
1348
1349         if (type & PERF_SAMPLE_CALLCHAIN) {
1350                 const u64 max_callchain_nr = UINT64_MAX / sizeof(u64);
1351
1352                 OVERFLOW_CHECK_u64(array);
1353                 data->callchain = (struct ip_callchain *)array++;
1354                 if (data->callchain->nr > max_callchain_nr)
1355                         return -EFAULT;
1356                 sz = data->callchain->nr * sizeof(u64);
1357                 OVERFLOW_CHECK(array, sz, max_size);
1358                 array = (void *)array + sz;
1359         }
1360
1361         if (type & PERF_SAMPLE_RAW) {
1362                 OVERFLOW_CHECK_u64(array);
1363                 u.val64 = *array;
1364                 if (WARN_ONCE(swapped,
1365                               "Endianness of raw data not corrected!\n")) {
1366                         /* undo swap of u64, then swap on individual u32s */
1367                         u.val64 = bswap_64(u.val64);
1368                         u.val32[0] = bswap_32(u.val32[0]);
1369                         u.val32[1] = bswap_32(u.val32[1]);
1370                 }
1371                 data->raw_size = u.val32[0];
1372                 array = (void *)array + sizeof(u32);
1373
1374                 OVERFLOW_CHECK(array, data->raw_size, max_size);
1375                 data->raw_data = (void *)array;
1376                 array = (void *)array + data->raw_size;
1377         }
1378
1379         if (type & PERF_SAMPLE_BRANCH_STACK) {
1380                 const u64 max_branch_nr = UINT64_MAX /
1381                                           sizeof(struct branch_entry);
1382
1383                 OVERFLOW_CHECK_u64(array);
1384                 data->branch_stack = (struct branch_stack *)array++;
1385
1386                 if (data->branch_stack->nr > max_branch_nr)
1387                         return -EFAULT;
1388                 sz = data->branch_stack->nr * sizeof(struct branch_entry);
1389                 OVERFLOW_CHECK(array, sz, max_size);
1390                 array = (void *)array + sz;
1391         }
1392
1393         if (type & PERF_SAMPLE_REGS_USER) {
1394                 OVERFLOW_CHECK_u64(array);
1395                 data->user_regs.abi = *array;
1396                 array++;
1397
1398                 if (data->user_regs.abi) {
1399                         u64 regs_user = evsel->attr.sample_regs_user;
1400
1401                         sz = hweight_long(regs_user) * sizeof(u64);
1402                         OVERFLOW_CHECK(array, sz, max_size);
1403                         data->user_regs.regs = (u64 *)array;
1404                         array = (void *)array + sz;
1405                 }
1406         }
1407
1408         if (type & PERF_SAMPLE_STACK_USER) {
1409                 OVERFLOW_CHECK_u64(array);
1410                 sz = *array++;
1411
1412                 data->user_stack.offset = ((char *)(array - 1)
1413                                           - (char *) event);
1414
1415                 if (!sz) {
1416                         data->user_stack.size = 0;
1417                 } else {
1418                         OVERFLOW_CHECK(array, sz, max_size);
1419                         data->user_stack.data = (char *)array;
1420                         array = (void *)array + sz;
1421                         OVERFLOW_CHECK_u64(array);
1422                         data->user_stack.size = *array++;
1423                         if (WARN_ONCE(data->user_stack.size > sz,
1424                                       "user stack dump failure\n"))
1425                                 return -EFAULT;
1426                 }
1427         }
1428
1429         data->weight = 0;
1430         if (type & PERF_SAMPLE_WEIGHT) {
1431                 OVERFLOW_CHECK_u64(array);
1432                 data->weight = *array;
1433                 array++;
1434         }
1435
1436         data->data_src = PERF_MEM_DATA_SRC_NONE;
1437         if (type & PERF_SAMPLE_DATA_SRC) {
1438                 OVERFLOW_CHECK_u64(array);
1439                 data->data_src = *array;
1440                 array++;
1441         }
1442
1443         data->transaction = 0;
1444         if (type & PERF_SAMPLE_TRANSACTION) {
1445                 OVERFLOW_CHECK_u64(array);
1446                 data->transaction = *array;
1447                 array++;
1448         }
1449
1450         return 0;
1451 }
1452
1453 size_t perf_event__sample_event_size(const struct perf_sample *sample, u64 type,
1454                                      u64 sample_regs_user, u64 read_format)
1455 {
1456         size_t sz, result = sizeof(struct sample_event);
1457
1458         if (type & PERF_SAMPLE_IDENTIFIER)
1459                 result += sizeof(u64);
1460
1461         if (type & PERF_SAMPLE_IP)
1462                 result += sizeof(u64);
1463
1464         if (type & PERF_SAMPLE_TID)
1465                 result += sizeof(u64);
1466
1467         if (type & PERF_SAMPLE_TIME)
1468                 result += sizeof(u64);
1469
1470         if (type & PERF_SAMPLE_ADDR)
1471                 result += sizeof(u64);
1472
1473         if (type & PERF_SAMPLE_ID)
1474                 result += sizeof(u64);
1475
1476         if (type & PERF_SAMPLE_STREAM_ID)
1477                 result += sizeof(u64);
1478
1479         if (type & PERF_SAMPLE_CPU)
1480                 result += sizeof(u64);
1481
1482         if (type & PERF_SAMPLE_PERIOD)
1483                 result += sizeof(u64);
1484
1485         if (type & PERF_SAMPLE_READ) {
1486                 result += sizeof(u64);
1487                 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
1488                         result += sizeof(u64);
1489                 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
1490                         result += sizeof(u64);
1491                 /* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1492                 if (read_format & PERF_FORMAT_GROUP) {
1493                         sz = sample->read.group.nr *
1494                              sizeof(struct sample_read_value);
1495                         result += sz;
1496                 } else {
1497                         result += sizeof(u64);
1498                 }
1499         }
1500
1501         if (type & PERF_SAMPLE_CALLCHAIN) {
1502                 sz = (sample->callchain->nr + 1) * sizeof(u64);
1503                 result += sz;
1504         }
1505
1506         if (type & PERF_SAMPLE_RAW) {
1507                 result += sizeof(u32);
1508                 result += sample->raw_size;
1509         }
1510
1511         if (type & PERF_SAMPLE_BRANCH_STACK) {
1512                 sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1513                 sz += sizeof(u64);
1514                 result += sz;
1515         }
1516
1517         if (type & PERF_SAMPLE_REGS_USER) {
1518                 if (sample->user_regs.abi) {
1519                         result += sizeof(u64);
1520                         sz = hweight_long(sample_regs_user) * sizeof(u64);
1521                         result += sz;
1522                 } else {
1523                         result += sizeof(u64);
1524                 }
1525         }
1526
1527         if (type & PERF_SAMPLE_STACK_USER) {
1528                 sz = sample->user_stack.size;
1529                 result += sizeof(u64);
1530                 if (sz) {
1531                         result += sz;
1532                         result += sizeof(u64);
1533                 }
1534         }
1535
1536         if (type & PERF_SAMPLE_WEIGHT)
1537                 result += sizeof(u64);
1538
1539         if (type & PERF_SAMPLE_DATA_SRC)
1540                 result += sizeof(u64);
1541
1542         if (type & PERF_SAMPLE_TRANSACTION)
1543                 result += sizeof(u64);
1544
1545         return result;
1546 }
1547
1548 int perf_event__synthesize_sample(union perf_event *event, u64 type,
1549                                   u64 sample_regs_user, u64 read_format,
1550                                   const struct perf_sample *sample,
1551                                   bool swapped)
1552 {
1553         u64 *array;
1554         size_t sz;
1555         /*
1556          * used for cross-endian analysis. See git commit 65014ab3
1557          * for why this goofiness is needed.
1558          */
1559         union u64_swap u;
1560
1561         array = event->sample.array;
1562
1563         if (type & PERF_SAMPLE_IDENTIFIER) {
1564                 *array = sample->id;
1565                 array++;
1566         }
1567
1568         if (type & PERF_SAMPLE_IP) {
1569                 *array = sample->ip;
1570                 array++;
1571         }
1572
1573         if (type & PERF_SAMPLE_TID) {
1574                 u.val32[0] = sample->pid;
1575                 u.val32[1] = sample->tid;
1576                 if (swapped) {
1577                         /*
1578                          * Inverse of what is done in perf_evsel__parse_sample
1579                          */
1580                         u.val32[0] = bswap_32(u.val32[0]);
1581                         u.val32[1] = bswap_32(u.val32[1]);
1582                         u.val64 = bswap_64(u.val64);
1583                 }
1584
1585                 *array = u.val64;
1586                 array++;
1587         }
1588
1589         if (type & PERF_SAMPLE_TIME) {
1590                 *array = sample->time;
1591                 array++;
1592         }
1593
1594         if (type & PERF_SAMPLE_ADDR) {
1595                 *array = sample->addr;
1596                 array++;
1597         }
1598
1599         if (type & PERF_SAMPLE_ID) {
1600                 *array = sample->id;
1601                 array++;
1602         }
1603
1604         if (type & PERF_SAMPLE_STREAM_ID) {
1605                 *array = sample->stream_id;
1606                 array++;
1607         }
1608
1609         if (type & PERF_SAMPLE_CPU) {
1610                 u.val32[0] = sample->cpu;
1611                 if (swapped) {
1612                         /*
1613                          * Inverse of what is done in perf_evsel__parse_sample
1614                          */
1615                         u.val32[0] = bswap_32(u.val32[0]);
1616                         u.val64 = bswap_64(u.val64);
1617                 }
1618                 *array = u.val64;
1619                 array++;
1620         }
1621
1622         if (type & PERF_SAMPLE_PERIOD) {
1623                 *array = sample->period;
1624                 array++;
1625         }
1626
1627         if (type & PERF_SAMPLE_READ) {
1628                 if (read_format & PERF_FORMAT_GROUP)
1629                         *array = sample->read.group.nr;
1630                 else
1631                         *array = sample->read.one.value;
1632                 array++;
1633
1634                 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1635                         *array = sample->read.time_enabled;
1636                         array++;
1637                 }
1638
1639                 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1640                         *array = sample->read.time_running;
1641                         array++;
1642                 }
1643
1644                 /* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1645                 if (read_format & PERF_FORMAT_GROUP) {
1646                         sz = sample->read.group.nr *
1647                              sizeof(struct sample_read_value);
1648                         memcpy(array, sample->read.group.values, sz);
1649                         array = (void *)array + sz;
1650                 } else {
1651                         *array = sample->read.one.id;
1652                         array++;
1653                 }
1654         }
1655
1656         if (type & PERF_SAMPLE_CALLCHAIN) {
1657                 sz = (sample->callchain->nr + 1) * sizeof(u64);
1658                 memcpy(array, sample->callchain, sz);
1659                 array = (void *)array + sz;
1660         }
1661
1662         if (type & PERF_SAMPLE_RAW) {
1663                 u.val32[0] = sample->raw_size;
1664                 if (WARN_ONCE(swapped,
1665                               "Endianness of raw data not corrected!\n")) {
1666                         /*
1667                          * Inverse of what is done in perf_evsel__parse_sample
1668                          */
1669                         u.val32[0] = bswap_32(u.val32[0]);
1670                         u.val32[1] = bswap_32(u.val32[1]);
1671                         u.val64 = bswap_64(u.val64);
1672                 }
1673                 *array = u.val64;
1674                 array = (void *)array + sizeof(u32);
1675
1676                 memcpy(array, sample->raw_data, sample->raw_size);
1677                 array = (void *)array + sample->raw_size;
1678         }
1679
1680         if (type & PERF_SAMPLE_BRANCH_STACK) {
1681                 sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1682                 sz += sizeof(u64);
1683                 memcpy(array, sample->branch_stack, sz);
1684                 array = (void *)array + sz;
1685         }
1686
1687         if (type & PERF_SAMPLE_REGS_USER) {
1688                 if (sample->user_regs.abi) {
1689                         *array++ = sample->user_regs.abi;
1690                         sz = hweight_long(sample_regs_user) * sizeof(u64);
1691                         memcpy(array, sample->user_regs.regs, sz);
1692                         array = (void *)array + sz;
1693                 } else {
1694                         *array++ = 0;
1695                 }
1696         }
1697
1698         if (type & PERF_SAMPLE_STACK_USER) {
1699                 sz = sample->user_stack.size;
1700                 *array++ = sz;
1701                 if (sz) {
1702                         memcpy(array, sample->user_stack.data, sz);
1703                         array = (void *)array + sz;
1704                         *array++ = sz;
1705                 }
1706         }
1707
1708         if (type & PERF_SAMPLE_WEIGHT) {
1709                 *array = sample->weight;
1710                 array++;
1711         }
1712
1713         if (type & PERF_SAMPLE_DATA_SRC) {
1714                 *array = sample->data_src;
1715                 array++;
1716         }
1717
1718         if (type & PERF_SAMPLE_TRANSACTION) {
1719                 *array = sample->transaction;
1720                 array++;
1721         }
1722
1723         return 0;
1724 }
1725
1726 struct format_field *perf_evsel__field(struct perf_evsel *evsel, const char *name)
1727 {
1728         return pevent_find_field(evsel->tp_format, name);
1729 }
1730
1731 void *perf_evsel__rawptr(struct perf_evsel *evsel, struct perf_sample *sample,
1732                          const char *name)
1733 {
1734         struct format_field *field = perf_evsel__field(evsel, name);
1735         int offset;
1736
1737         if (!field)
1738                 return NULL;
1739
1740         offset = field->offset;
1741
1742         if (field->flags & FIELD_IS_DYNAMIC) {
1743                 offset = *(int *)(sample->raw_data + field->offset);
1744                 offset &= 0xffff;
1745         }
1746
1747         return sample->raw_data + offset;
1748 }
1749
1750 u64 perf_evsel__intval(struct perf_evsel *evsel, struct perf_sample *sample,
1751                        const char *name)
1752 {
1753         struct format_field *field = perf_evsel__field(evsel, name);
1754         void *ptr;
1755         u64 value;
1756
1757         if (!field)
1758                 return 0;
1759
1760         ptr = sample->raw_data + field->offset;
1761
1762         switch (field->size) {
1763         case 1:
1764                 return *(u8 *)ptr;
1765         case 2:
1766                 value = *(u16 *)ptr;
1767                 break;
1768         case 4:
1769                 value = *(u32 *)ptr;
1770                 break;
1771         case 8:
1772                 value = *(u64 *)ptr;
1773                 break;
1774         default:
1775                 return 0;
1776         }
1777
1778         if (!evsel->needs_swap)
1779                 return value;
1780
1781         switch (field->size) {
1782         case 2:
1783                 return bswap_16(value);
1784         case 4:
1785                 return bswap_32(value);
1786         case 8:
1787                 return bswap_64(value);
1788         default:
1789                 return 0;
1790         }
1791
1792         return 0;
1793 }
1794
1795 static int comma_fprintf(FILE *fp, bool *first, const char *fmt, ...)
1796 {
1797         va_list args;
1798         int ret = 0;
1799
1800         if (!*first) {
1801                 ret += fprintf(fp, ",");
1802         } else {
1803                 ret += fprintf(fp, ":");
1804                 *first = false;
1805         }
1806
1807         va_start(args, fmt);
1808         ret += vfprintf(fp, fmt, args);
1809         va_end(args);
1810         return ret;
1811 }
1812
1813 static int __if_fprintf(FILE *fp, bool *first, const char *field, u64 value)
1814 {
1815         if (value == 0)
1816                 return 0;
1817
1818         return comma_fprintf(fp, first, " %s: %" PRIu64, field, value);
1819 }
1820
1821 #define if_print(field) printed += __if_fprintf(fp, &first, #field, evsel->attr.field)
1822
1823 struct bit_names {
1824         int bit;
1825         const char *name;
1826 };
1827
1828 static int bits__fprintf(FILE *fp, const char *field, u64 value,
1829                          struct bit_names *bits, bool *first)
1830 {
1831         int i = 0, printed = comma_fprintf(fp, first, " %s: ", field);
1832         bool first_bit = true;
1833
1834         do {
1835                 if (value & bits[i].bit) {
1836                         printed += fprintf(fp, "%s%s", first_bit ? "" : "|", bits[i].name);
1837                         first_bit = false;
1838                 }
1839         } while (bits[++i].name != NULL);
1840
1841         return printed;
1842 }
1843
1844 static int sample_type__fprintf(FILE *fp, bool *first, u64 value)
1845 {
1846 #define bit_name(n) { PERF_SAMPLE_##n, #n }
1847         struct bit_names bits[] = {
1848                 bit_name(IP), bit_name(TID), bit_name(TIME), bit_name(ADDR),
1849                 bit_name(READ), bit_name(CALLCHAIN), bit_name(ID), bit_name(CPU),
1850                 bit_name(PERIOD), bit_name(STREAM_ID), bit_name(RAW),
1851                 bit_name(BRANCH_STACK), bit_name(REGS_USER), bit_name(STACK_USER),
1852                 bit_name(IDENTIFIER),
1853                 { .name = NULL, }
1854         };
1855 #undef bit_name
1856         return bits__fprintf(fp, "sample_type", value, bits, first);
1857 }
1858
1859 static int read_format__fprintf(FILE *fp, bool *first, u64 value)
1860 {
1861 #define bit_name(n) { PERF_FORMAT_##n, #n }
1862         struct bit_names bits[] = {
1863                 bit_name(TOTAL_TIME_ENABLED), bit_name(TOTAL_TIME_RUNNING),
1864                 bit_name(ID), bit_name(GROUP),
1865                 { .name = NULL, }
1866         };
1867 #undef bit_name
1868         return bits__fprintf(fp, "read_format", value, bits, first);
1869 }
1870
1871 int perf_evsel__fprintf(struct perf_evsel *evsel,
1872                         struct perf_attr_details *details, FILE *fp)
1873 {
1874         bool first = true;
1875         int printed = 0;
1876
1877         if (details->event_group) {
1878                 struct perf_evsel *pos;
1879
1880                 if (!perf_evsel__is_group_leader(evsel))
1881                         return 0;
1882
1883                 if (evsel->nr_members > 1)
1884                         printed += fprintf(fp, "%s{", evsel->group_name ?: "");
1885
1886                 printed += fprintf(fp, "%s", perf_evsel__name(evsel));
1887                 for_each_group_member(pos, evsel)
1888                         printed += fprintf(fp, ",%s", perf_evsel__name(pos));
1889
1890                 if (evsel->nr_members > 1)
1891                         printed += fprintf(fp, "}");
1892                 goto out;
1893         }
1894
1895         printed += fprintf(fp, "%s", perf_evsel__name(evsel));
1896
1897         if (details->verbose || details->freq) {
1898                 printed += comma_fprintf(fp, &first, " sample_freq=%" PRIu64,
1899                                          (u64)evsel->attr.sample_freq);
1900         }
1901
1902         if (details->verbose) {
1903                 if_print(type);
1904                 if_print(config);
1905                 if_print(config1);
1906                 if_print(config2);
1907                 if_print(size);
1908                 printed += sample_type__fprintf(fp, &first, evsel->attr.sample_type);
1909                 if (evsel->attr.read_format)
1910                         printed += read_format__fprintf(fp, &first, evsel->attr.read_format);
1911                 if_print(disabled);
1912                 if_print(inherit);
1913                 if_print(pinned);
1914                 if_print(exclusive);
1915                 if_print(exclude_user);
1916                 if_print(exclude_kernel);
1917                 if_print(exclude_hv);
1918                 if_print(exclude_idle);
1919                 if_print(mmap);
1920                 if_print(mmap2);
1921                 if_print(comm);
1922                 if_print(freq);
1923                 if_print(inherit_stat);
1924                 if_print(enable_on_exec);
1925                 if_print(task);
1926                 if_print(watermark);
1927                 if_print(precise_ip);
1928                 if_print(mmap_data);
1929                 if_print(sample_id_all);
1930                 if_print(exclude_host);
1931                 if_print(exclude_guest);
1932                 if_print(__reserved_1);
1933                 if_print(wakeup_events);
1934                 if_print(bp_type);
1935                 if_print(branch_sample_type);
1936         }
1937 out:
1938         fputc('\n', fp);
1939         return ++printed;
1940 }
1941
1942 bool perf_evsel__fallback(struct perf_evsel *evsel, int err,
1943                           char *msg, size_t msgsize)
1944 {
1945         if ((err == ENOENT || err == ENXIO || err == ENODEV) &&
1946             evsel->attr.type   == PERF_TYPE_HARDWARE &&
1947             evsel->attr.config == PERF_COUNT_HW_CPU_CYCLES) {
1948                 /*
1949                  * If it's cycles then fall back to hrtimer based
1950                  * cpu-clock-tick sw counter, which is always available even if
1951                  * no PMU support.
1952                  *
1953                  * PPC returns ENXIO until 2.6.37 (behavior changed with commit
1954                  * b0a873e).
1955                  */
1956                 scnprintf(msg, msgsize, "%s",
1957 "The cycles event is not supported, trying to fall back to cpu-clock-ticks");
1958
1959                 evsel->attr.type   = PERF_TYPE_SOFTWARE;
1960                 evsel->attr.config = PERF_COUNT_SW_CPU_CLOCK;
1961
1962                 zfree(&evsel->name);
1963                 return true;
1964         }
1965
1966         return false;
1967 }
1968
1969 int perf_evsel__open_strerror(struct perf_evsel *evsel, struct target *target,
1970                               int err, char *msg, size_t size)
1971 {
1972         switch (err) {
1973         case EPERM:
1974         case EACCES:
1975                 return scnprintf(msg, size,
1976                  "You may not have permission to collect %sstats.\n"
1977                  "Consider tweaking /proc/sys/kernel/perf_event_paranoid:\n"
1978                  " -1 - Not paranoid at all\n"
1979                  "  0 - Disallow raw tracepoint access for unpriv\n"
1980                  "  1 - Disallow cpu events for unpriv\n"
1981                  "  2 - Disallow kernel profiling for unpriv",
1982                                  target->system_wide ? "system-wide " : "");
1983         case ENOENT:
1984                 return scnprintf(msg, size, "The %s event is not supported.",
1985                                  perf_evsel__name(evsel));
1986         case EMFILE:
1987                 return scnprintf(msg, size, "%s",
1988                          "Too many events are opened.\n"
1989                          "Try again after reducing the number of events.");
1990         case ENODEV:
1991                 if (target->cpu_list)
1992                         return scnprintf(msg, size, "%s",
1993          "No such device - did you specify an out-of-range profile CPU?\n");
1994                 break;
1995         case EOPNOTSUPP:
1996                 if (evsel->attr.precise_ip)
1997                         return scnprintf(msg, size, "%s",
1998         "\'precise\' request may not be supported. Try removing 'p' modifier.");
1999 #if defined(__i386__) || defined(__x86_64__)
2000                 if (evsel->attr.type == PERF_TYPE_HARDWARE)
2001                         return scnprintf(msg, size, "%s",
2002         "No hardware sampling interrupt available.\n"
2003         "No APIC? If so then you can boot the kernel with the \"lapic\" boot parameter to force-enable it.");
2004 #endif
2005                 break;
2006         default:
2007                 break;
2008         }
2009
2010         return scnprintf(msg, size,
2011         "The sys_perf_event_open() syscall returned with %d (%s) for event (%s).  \n"
2012         "/bin/dmesg may provide additional information.\n"
2013         "No CONFIG_PERF_EVENTS=y kernel support configured?\n",
2014                          err, strerror(err), perf_evsel__name(evsel));
2015 }