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 <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         bool cloexec;
  33 } perf_missing_features;
  34
  35 #define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
  36
  37 int __perf_evsel__sample_size(u64 sample_type)
  38 {
  39         u64 mask = sample_type & PERF_SAMPLE_MASK;
  40         int size = 0;
  41         int i;
  42
  43         for (i = 0; i < 64; i++) {
  44                 if (mask & (1ULL << i))
  45                         size++;
  46         }
  47
  48         size *= sizeof(u64);
  49
  50         return size;
  51 }
  52
  53 /**
  54  * __perf_evsel__calc_id_pos - calculate id_pos.
  55  * @sample_type: sample type
  56  *
  57  * This function returns the position of the event id (PERF_SAMPLE_ID or
  58  * PERF_SAMPLE_IDENTIFIER) in a sample event i.e. in the array of struct
  59  * sample_event.
  60  */
  61 static int __perf_evsel__calc_id_pos(u64 sample_type)
  62 {
  63         int idx = 0;
  64
  65         if (sample_type & PERF_SAMPLE_IDENTIFIER)
  66                 return 0;
  67
  68         if (!(sample_type & PERF_SAMPLE_ID))
  69                 return -1;
  70
  71         if (sample_type & PERF_SAMPLE_IP)
  72                 idx += 1;
  73
  74         if (sample_type & PERF_SAMPLE_TID)
  75                 idx += 1;
  76
  77         if (sample_type & PERF_SAMPLE_TIME)
  78                 idx += 1;
  79
  80         if (sample_type & PERF_SAMPLE_ADDR)
  81                 idx += 1;
  82
  83         return idx;
  84 }
  85
  86 /**
  87  * __perf_evsel__calc_is_pos - calculate is_pos.
  88  * @sample_type: sample type
  89  *
  90  * This function returns the position (counting backwards) of the event id
  91  * (PERF_SAMPLE_ID or PERF_SAMPLE_IDENTIFIER) in a non-sample event i.e. if
  92  * sample_id_all is used there is an id sample appended to non-sample events.
  93  */
  94 static int __perf_evsel__calc_is_pos(u64 sample_type)
  95 {
  96         int idx = 1;
  97
  98         if (sample_type & PERF_SAMPLE_IDENTIFIER)
  99                 return 1;
 100
 101         if (!(sample_type & PERF_SAMPLE_ID))
 102                 return -1;
 103
 104         if (sample_type & PERF_SAMPLE_CPU)
 105                 idx += 1;
 106
 107         if (sample_type & PERF_SAMPLE_STREAM_ID)
 108                 idx += 1;
 109
 110         return idx;
 111 }
 112
 113 void perf_evsel__calc_id_pos(struct perf_evsel *evsel)
 114 {
 115         evsel->id_pos = __perf_evsel__calc_id_pos(evsel->attr.sample_type);
 116         evsel->is_pos = __perf_evsel__calc_is_pos(evsel->attr.sample_type);
 117 }
 118
 119 void hists__init(struct hists *hists)
 120 {
 121         memset(hists, 0, sizeof(*hists));
 122         hists->entries_in_array[0] = hists->entries_in_array[1] = RB_ROOT;
 123         hists->entries_in = &hists->entries_in_array[0];
 124         hists->entries_collapsed = RB_ROOT;
 125         hists->entries = RB_ROOT;
 126         pthread_mutex_init(&hists->lock, NULL);
 127 }
 128
 129 void __perf_evsel__set_sample_bit(struct perf_evsel *evsel,
 130                                   enum perf_event_sample_format bit)
 131 {
 132         if (!(evsel->attr.sample_type & bit)) {
 133                 evsel->attr.sample_type |= bit;
 134                 evsel->sample_size += sizeof(u64);
 135                 perf_evsel__calc_id_pos(evsel);
 136         }
 137 }
 138
 139 void __perf_evsel__reset_sample_bit(struct perf_evsel *evsel,
 140                                     enum perf_event_sample_format bit)
 141 {
 142         if (evsel->attr.sample_type & bit) {
 143                 evsel->attr.sample_type &= ~bit;
 144                 evsel->sample_size -= sizeof(u64);
 145                 perf_evsel__calc_id_pos(evsel);
 146         }
 147 }
 148
 149 void perf_evsel__set_sample_id(struct perf_evsel *evsel,
 150                                bool can_sample_identifier)
 151 {
 152         if (can_sample_identifier) {
 153                 perf_evsel__reset_sample_bit(evsel, ID);
 154                 perf_evsel__set_sample_bit(evsel, IDENTIFIER);
 155         } else {
 156                 perf_evsel__set_sample_bit(evsel, ID);
 157         }
 158         evsel->attr.read_format |= PERF_FORMAT_ID;
 159 }
 160
 161 void perf_evsel__init(struct perf_evsel *evsel,
 162                       struct perf_event_attr *attr, int idx)
 163 {
 164         evsel->idx         = idx;
 165         evsel->attr        = *attr;
 166         evsel->leader      = evsel;
 167         evsel->unit        = "";
 168         evsel->scale       = 1.0;
 169         INIT_LIST_HEAD(&evsel->node);
 170         hists__init(&evsel->hists);
 171         evsel->sample_size = __perf_evsel__sample_size(attr->sample_type);
 172         perf_evsel__calc_id_pos(evsel);
 173 }
 174
 175 struct perf_evsel *perf_evsel__new_idx(struct perf_event_attr *attr, int idx)
 176 {
 177         struct perf_evsel *evsel = zalloc(sizeof(*evsel));
 178
 179         if (evsel != NULL)
 180                 perf_evsel__init(evsel, attr, idx);
 181
 182         return evsel;
 183 }
 184
 185 struct perf_evsel *perf_evsel__newtp_idx(const char *sys, const char *name, int idx)
 186 {
 187         struct perf_evsel *evsel = zalloc(sizeof(*evsel));
 188
 189         if (evsel != NULL) {
 190                 struct perf_event_attr attr = {
 191                         .type          = PERF_TYPE_TRACEPOINT,
 192                         .sample_type   = (PERF_SAMPLE_RAW | PERF_SAMPLE_TIME |
 193                                           PERF_SAMPLE_CPU | PERF_SAMPLE_PERIOD),
 194                 };
 195
 196                 if (asprintf(&evsel->name, "%s:%s", sys, name) < 0)
 197                         goto out_free;
 198
 199                 evsel->tp_format = trace_event__tp_format(sys, name);
 200                 if (evsel->tp_format == NULL)
 201                         goto out_free;
 202
 203                 event_attr_init(&attr);
 204                 attr.config = evsel->tp_format->id;
 205                 attr.sample_period = 1;
 206                 perf_evsel__init(evsel, &attr, idx);
 207         }
 208
 209         return evsel;
 210
 211 out_free:
 212         zfree(&evsel->name);
 213         free(evsel);
 214         return NULL;
 215 }
 216
 217 const char *perf_evsel__hw_names[PERF_COUNT_HW_MAX] = {
 218         "cycles",
 219         "instructions",
 220         "cache-references",
 221         "cache-misses",
 222         "branches",
 223         "branch-misses",
 224         "bus-cycles",
 225         "stalled-cycles-frontend",
 226         "stalled-cycles-backend",
 227         "ref-cycles",
 228 };
 229
 230 static const char *__perf_evsel__hw_name(u64 config)
 231 {
 232         if (config < PERF_COUNT_HW_MAX && perf_evsel__hw_names[config])
 233                 return perf_evsel__hw_names[config];
 234
 235         return "unknown-hardware";
 236 }
 237
 238 static int perf_evsel__add_modifiers(struct perf_evsel *evsel, char *bf, size_t size)
 239 {
 240         int colon = 0, r = 0;
 241         struct perf_event_attr *attr = &evsel->attr;
 242         bool exclude_guest_default = false;
 243
 244 #define MOD_PRINT(context, mod) do {                                    \
 245                 if (!attr->exclude_##context) {                         \
 246                         if (!colon) colon = ++r;                        \
 247                         r += scnprintf(bf + r, size - r, "%c", mod);    \
 248                 } } while(0)
 249
 250         if (attr->exclude_kernel || attr->exclude_user || attr->exclude_hv) {
 251                 MOD_PRINT(kernel, 'k');
 252                 MOD_PRINT(user, 'u');
 253                 MOD_PRINT(hv, 'h');
 254                 exclude_guest_default = true;
 255         }
 256
 257         if (attr->precise_ip) {
 258                 if (!colon)
 259                         colon = ++r;
 260                 r += scnprintf(bf + r, size - r, "%.*s", attr->precise_ip, "ppp");
 261                 exclude_guest_default = true;
 262         }
 263
 264         if (attr->exclude_host || attr->exclude_guest == exclude_guest_default) {
 265                 MOD_PRINT(host, 'H');
 266                 MOD_PRINT(guest, 'G');
 267         }
 268 #undef MOD_PRINT
 269         if (colon)
 270                 bf[colon - 1] = ':';
 271         return r;
 272 }
 273
 274 static int perf_evsel__hw_name(struct perf_evsel *evsel, char *bf, size_t size)
 275 {
 276         int r = scnprintf(bf, size, "%s", __perf_evsel__hw_name(evsel->attr.config));
 277         return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
 278 }
 279
 280 const char *perf_evsel__sw_names[PERF_COUNT_SW_MAX] = {
 281         "cpu-clock",
 282         "task-clock",
 283         "page-faults",
 284         "context-switches",
 285         "cpu-migrations",
 286         "minor-faults",
 287         "major-faults",
 288         "alignment-faults",
 289         "emulation-faults",
 290         "dummy",
 291 };
 292
 293 static const char *__perf_evsel__sw_name(u64 config)
 294 {
 295         if (config < PERF_COUNT_SW_MAX && perf_evsel__sw_names[config])
 296                 return perf_evsel__sw_names[config];
 297         return "unknown-software";
 298 }
 299
 300 static int perf_evsel__sw_name(struct perf_evsel *evsel, char *bf, size_t size)
 301 {
 302         int r = scnprintf(bf, size, "%s", __perf_evsel__sw_name(evsel->attr.config));
 303         return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
 304 }
 305
 306 static int __perf_evsel__bp_name(char *bf, size_t size, u64 addr, u64 type)
 307 {
 308         int r;
 309
 310         r = scnprintf(bf, size, "mem:0x%" PRIx64 ":", addr);
 311
 312         if (type & HW_BREAKPOINT_R)
 313                 r += scnprintf(bf + r, size - r, "r");
 314
 315         if (type & HW_BREAKPOINT_W)
 316                 r += scnprintf(bf + r, size - r, "w");
 317
 318         if (type & HW_BREAKPOINT_X)
 319                 r += scnprintf(bf + r, size - r, "x");
 320
 321         return r;
 322 }
 323
 324 static int perf_evsel__bp_name(struct perf_evsel *evsel, char *bf, size_t size)
 325 {
 326         struct perf_event_attr *attr = &evsel->attr;
 327         int r = __perf_evsel__bp_name(bf, size, attr->bp_addr, attr->bp_type);
 328         return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
 329 }
 330
 331 const char *perf_evsel__hw_cache[PERF_COUNT_HW_CACHE_MAX]
 332                                 [PERF_EVSEL__MAX_ALIASES] = {
 333  { "L1-dcache", "l1-d",         "l1d",          "L1-data",              },
 334  { "L1-icache", "l1-i",         "l1i",          "L1-instruction",       },
 335  { "LLC",       "L2",                                                   },
 336  { "dTLB",      "d-tlb",        "Data-TLB",                             },
 337  { "iTLB",      "i-tlb",        "Instruction-TLB",                      },
 338  { "branch",    "branches",     "bpu",          "btb",          "bpc",  },
 339  { "node",                                                              },
 340 };
 341
 342 const char *perf_evsel__hw_cache_op[PERF_COUNT_HW_CACHE_OP_MAX]
 343                                    [PERF_EVSEL__MAX_ALIASES] = {
 344  { "load",      "loads",        "read",                                 },
 345  { "store",     "stores",       "write",                                },
 346  { "prefetch",  "prefetches",   "speculative-read", "speculative-load", },
 347 };
 348
 349 const char *perf_evsel__hw_cache_result[PERF_COUNT_HW_CACHE_RESULT_MAX]
 350                                        [PERF_EVSEL__MAX_ALIASES] = {
 351  { "refs",      "Reference",    "ops",          "access",               },
 352  { "misses",    "miss",                                                 },
 353 };
 354
 355 #define C(x)            PERF_COUNT_HW_CACHE_##x
 356 #define CACHE_READ      (1 << C(OP_READ))
 357 #define CACHE_WRITE     (1 << C(OP_WRITE))
 358 #define CACHE_PREFETCH  (1 << C(OP_PREFETCH))
 359 #define COP(x)          (1 << x)
 360
 361 /*
 362  * cache operartion stat
 363  * L1I : Read and prefetch only
 364  * ITLB and BPU : Read-only
 365  */
 366 static unsigned long perf_evsel__hw_cache_stat[C(MAX)] = {
 367  [C(L1D)]       = (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 368  [C(L1I)]       = (CACHE_READ | CACHE_PREFETCH),
 369  [C(LL)]        = (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 370  [C(DTLB)]      = (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 371  [C(ITLB)]      = (CACHE_READ),
 372  [C(BPU)]       = (CACHE_READ),
 373  [C(NODE)]      = (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 374 };
 375
 376 bool perf_evsel__is_cache_op_valid(u8 type, u8 op)
 377 {
 378         if (perf_evsel__hw_cache_stat[type] & COP(op))
 379                 return true;    /* valid */
 380         else
 381                 return false;   /* invalid */
 382 }
 383
 384 int __perf_evsel__hw_cache_type_op_res_name(u8 type, u8 op, u8 result,
 385                                             char *bf, size_t size)
 386 {
 387         if (result) {
 388                 return scnprintf(bf, size, "%s-%s-%s", perf_evsel__hw_cache[type][0],
 389                                  perf_evsel__hw_cache_op[op][0],
 390                                  perf_evsel__hw_cache_result[result][0]);
 391         }
 392
 393         return scnprintf(bf, size, "%s-%s", perf_evsel__hw_cache[type][0],
 394                          perf_evsel__hw_cache_op[op][1]);
 395 }
 396
 397 static int __perf_evsel__hw_cache_name(u64 config, char *bf, size_t size)
 398 {
 399         u8 op, result, type = (config >>  0) & 0xff;
 400         const char *err = "unknown-ext-hardware-cache-type";
 401
 402         if (type > PERF_COUNT_HW_CACHE_MAX)
 403                 goto out_err;
 404
 405         op = (config >>  8) & 0xff;
 406         err = "unknown-ext-hardware-cache-op";
 407         if (op > PERF_COUNT_HW_CACHE_OP_MAX)
 408                 goto out_err;
 409
 410         result = (config >> 16) & 0xff;
 411         err = "unknown-ext-hardware-cache-result";
 412         if (result > PERF_COUNT_HW_CACHE_RESULT_MAX)
 413                 goto out_err;
 414
 415         err = "invalid-cache";
 416         if (!perf_evsel__is_cache_op_valid(type, op))
 417                 goto out_err;
 418
 419         return __perf_evsel__hw_cache_type_op_res_name(type, op, result, bf, size);
 420 out_err:
 421         return scnprintf(bf, size, "%s", err);
 422 }
 423
 424 static int perf_evsel__hw_cache_name(struct perf_evsel *evsel, char *bf, size_t size)
 425 {
 426         int ret = __perf_evsel__hw_cache_name(evsel->attr.config, bf, size);
 427         return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
 428 }
 429
 430 static int perf_evsel__raw_name(struct perf_evsel *evsel, char *bf, size_t size)
 431 {
 432         int ret = scnprintf(bf, size, "raw 0x%" PRIx64, evsel->attr.config);
 433         return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
 434 }
 435
 436 const char *perf_evsel__name(struct perf_evsel *evsel)
 437 {
 438         char bf[128];
 439
 440         if (evsel->name)
 441                 return evsel->name;
 442
 443         switch (evsel->attr.type) {
 444         case PERF_TYPE_RAW:
 445                 perf_evsel__raw_name(evsel, bf, sizeof(bf));
 446                 break;
 447
 448         case PERF_TYPE_HARDWARE:
 449                 perf_evsel__hw_name(evsel, bf, sizeof(bf));
 450                 break;
 451
 452         case PERF_TYPE_HW_CACHE:
 453                 perf_evsel__hw_cache_name(evsel, bf, sizeof(bf));
 454                 break;
 455
 456         case PERF_TYPE_SOFTWARE:
 457                 perf_evsel__sw_name(evsel, bf, sizeof(bf));
 458                 break;
 459
 460         case PERF_TYPE_TRACEPOINT:
 461                 scnprintf(bf, sizeof(bf), "%s", "unknown tracepoint");
 462                 break;
 463
 464         case PERF_TYPE_BREAKPOINT:
 465                 perf_evsel__bp_name(evsel, bf, sizeof(bf));
 466                 break;
 467
 468         default:
 469                 scnprintf(bf, sizeof(bf), "unknown attr type: %d",
 470                           evsel->attr.type);
 471                 break;
 472         }
 473
 474         evsel->name = strdup(bf);
 475
 476         return evsel->name ?: "unknown";
 477 }
 478
 479 const char *perf_evsel__group_name(struct perf_evsel *evsel)
 480 {
 481         return evsel->group_name ?: "anon group";
 482 }
 483
 484 int perf_evsel__group_desc(struct perf_evsel *evsel, char *buf, size_t size)
 485 {
 486         int ret;
 487         struct perf_evsel *pos;
 488         const char *group_name = perf_evsel__group_name(evsel);
 489
 490         ret = scnprintf(buf, size, "%s", group_name);
 491
 492         ret += scnprintf(buf + ret, size - ret, " { %s",
 493                          perf_evsel__name(evsel));
 494
 495         for_each_group_member(pos, evsel)
 496                 ret += scnprintf(buf + ret, size - ret, ", %s",
 497                                  perf_evsel__name(pos));
 498
 499         ret += scnprintf(buf + ret, size - ret, " }");
 500
 501         return ret;
 502 }
 503
 504 static void
 505 perf_evsel__config_callgraph(struct perf_evsel *evsel,
 506                              struct record_opts *opts)
 507 {
 508         bool function = perf_evsel__is_function_event(evsel);
 509         struct perf_event_attr *attr = &evsel->attr;
 510
 511         perf_evsel__set_sample_bit(evsel, CALLCHAIN);
 512
 513         if (opts->call_graph == CALLCHAIN_DWARF) {
 514                 if (!function) {
 515                         perf_evsel__set_sample_bit(evsel, REGS_USER);
 516                         perf_evsel__set_sample_bit(evsel, STACK_USER);
 517                         attr->sample_regs_user = PERF_REGS_MASK;
 518                         attr->sample_stack_user = opts->stack_dump_size;
 519                         attr->exclude_callchain_user = 1;
 520                 } else {
 521                         pr_info("Cannot use DWARF unwind for function trace event,"
 522                                 " falling back to framepointers.\n");
 523                 }
 524         }
 525
 526         if (function) {
 527                 pr_info("Disabling user space callchains for function trace event.\n");
 528                 attr->exclude_callchain_user = 1;
 529         }
 530 }
 531
 532 /*
 533  * The enable_on_exec/disabled value strategy:
 534  *
 535  *  1) For any type of traced program:
 536  *    - all independent events and group leaders are disabled
 537  *    - all group members are enabled
 538  *
 539  *     Group members are ruled by group leaders. They need to
 540  *     be enabled, because the group scheduling relies on that.
 541  *
 542  *  2) For traced programs executed by perf:
 543  *     - all independent events and group leaders have
 544  *       enable_on_exec set
 545  *     - we don't specifically enable or disable any event during
 546  *       the record command
 547  *
 548  *     Independent events and group leaders are initially disabled
 549  *     and get enabled by exec. Group members are ruled by group
 550  *     leaders as stated in 1).
 551  *
 552  *  3) For traced programs attached by perf (pid/tid):
 553  *     - we specifically enable or disable all events during
 554  *       the record command
 555  *
 556  *     When attaching events to already running traced we
 557  *     enable/disable events specifically, as there's no
 558  *     initial traced exec call.
 559  */
 560 void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts)
 561 {
 562         struct perf_evsel *leader = evsel->leader;
 563         struct perf_event_attr *attr = &evsel->attr;
 564         int track = !evsel->idx; /* only the first counter needs these */
 565         bool per_cpu = opts->target.default_per_cpu && !opts->target.per_thread;
 566
 567         attr->sample_id_all = perf_missing_features.sample_id_all ? 0 : 1;
 568         attr->inherit       = !opts->no_inherit;
 569
 570         perf_evsel__set_sample_bit(evsel, IP);
 571         perf_evsel__set_sample_bit(evsel, TID);
 572
 573         if (evsel->sample_read) {
 574                 perf_evsel__set_sample_bit(evsel, READ);
 575
 576                 /*
 577                  * We need ID even in case of single event, because
 578                  * PERF_SAMPLE_READ process ID specific data.
 579                  */
 580                 perf_evsel__set_sample_id(evsel, false);
 581
 582                 /*
 583                  * Apply group format only if we belong to group
 584                  * with more than one members.
 585                  */
 586                 if (leader->nr_members > 1) {
 587                         attr->read_format |= PERF_FORMAT_GROUP;
 588                         attr->inherit = 0;
 589                 }
 590         }
 591
 592         /*
 593          * We default some events to have a default interval. But keep
 594          * it a weak assumption overridable by the user.
 595          */
 596         if (!attr->sample_period || (opts->user_freq != UINT_MAX ||
 597                                      opts->user_interval != ULLONG_MAX)) {
 598                 if (opts->freq) {
 599                         perf_evsel__set_sample_bit(evsel, PERIOD);
 600                         attr->freq              = 1;
 601                         attr->sample_freq       = opts->freq;
 602                 } else {
 603                         attr->sample_period = opts->default_interval;
 604                 }
 605         }
 606
 607         /*
 608          * Disable sampling for all group members other
 609          * than leader in case leader 'leads' the sampling.
 610          */
 611         if ((leader != evsel) && leader->sample_read) {
 612                 attr->sample_freq   = 0;
 613                 attr->sample_period = 0;
 614         }
 615
 616         if (opts->no_samples)
 617                 attr->sample_freq = 0;
 618
 619         if (opts->inherit_stat)
 620                 attr->inherit_stat = 1;
 621
 622         if (opts->sample_address) {
 623                 perf_evsel__set_sample_bit(evsel, ADDR);
 624                 attr->mmap_data = track;
 625         }
 626
 627         if (opts->call_graph_enabled && !evsel->no_aux_samples)
 628                 perf_evsel__config_callgraph(evsel, opts);
 629
 630         if (target__has_cpu(&opts->target))
 631                 perf_evsel__set_sample_bit(evsel, CPU);
 632
 633         if (opts->period)
 634                 perf_evsel__set_sample_bit(evsel, PERIOD);
 635
 636         if (!perf_missing_features.sample_id_all &&
 637             (opts->sample_time || !opts->no_inherit ||
 638              target__has_cpu(&opts->target) || per_cpu))
 639                 perf_evsel__set_sample_bit(evsel, TIME);
 640
 641         if (opts->raw_samples && !evsel->no_aux_samples) {
 642                 perf_evsel__set_sample_bit(evsel, TIME);
 643                 perf_evsel__set_sample_bit(evsel, RAW);
 644                 perf_evsel__set_sample_bit(evsel, CPU);
 645         }
 646
 647         if (opts->sample_address)
 648                 perf_evsel__set_sample_bit(evsel, DATA_SRC);
 649
 650         if (opts->no_buffering) {
 651                 attr->watermark = 0;
 652                 attr->wakeup_events = 1;
 653         }
 654         if (opts->branch_stack && !evsel->no_aux_samples) {
 655                 perf_evsel__set_sample_bit(evsel, BRANCH_STACK);
 656                 attr->branch_sample_type = opts->branch_stack;
 657         }
 658
 659         if (opts->sample_weight)
 660                 perf_evsel__set_sample_bit(evsel, WEIGHT);
 661
 662         attr->mmap  = track;
 663         attr->mmap2 = track && !perf_missing_features.mmap2;
 664         attr->comm  = track;
 665
 666         if (opts->sample_transaction)
 667                 perf_evsel__set_sample_bit(evsel, TRANSACTION);
 668
 669         /*
 670          * XXX see the function comment above
 671          *
 672          * Disabling only independent events or group leaders,
 673          * keeping group members enabled.
 674          */
 675         if (perf_evsel__is_group_leader(evsel))
 676                 attr->disabled = 1;
 677
 678         /*
 679          * Setting enable_on_exec for independent events and
 680          * group leaders for traced executed by perf.
 681          */
 682         if (target__none(&opts->target) && perf_evsel__is_group_leader(evsel) &&
 683                 !opts->initial_delay)
 684                 attr->enable_on_exec = 1;
 685
 686         if (evsel->immediate) {
 687                 attr->disabled = 0;
 688                 attr->enable_on_exec = 0;
 689         }
 690 }
 691
 692 int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
 693 {
 694         int cpu, thread;
 695         evsel->fd = xyarray__new(ncpus, nthreads, sizeof(int));
 696
 697         if (evsel->fd) {
 698                 for (cpu = 0; cpu < ncpus; cpu++) {
 699                         for (thread = 0; thread < nthreads; thread++) {
 700                                 FD(evsel, cpu, thread) = -1;
 701                         }
 702                 }
 703         }
 704
 705         return evsel->fd != NULL ? 0 : -ENOMEM;
 706 }
 707
 708 static int perf_evsel__run_ioctl(struct perf_evsel *evsel, int ncpus, int nthreads,
 709                           int ioc,  void *arg)
 710 {
 711         int cpu, thread;
 712
 713         for (cpu = 0; cpu < ncpus; cpu++) {
 714                 for (thread = 0; thread < nthreads; thread++) {
 715                         int fd = FD(evsel, cpu, thread),
 716                             err = ioctl(fd, ioc, arg);
 717
 718                         if (err)
 719                                 return err;
 720                 }
 721         }
 722
 723         return 0;
 724 }
 725
 726 int perf_evsel__set_filter(struct perf_evsel *evsel, int ncpus, int nthreads,
 727                            const char *filter)
 728 {
 729         return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
 730                                      PERF_EVENT_IOC_SET_FILTER,
 731                                      (void *)filter);
 732 }
 733
 734 int perf_evsel__enable(struct perf_evsel *evsel, int ncpus, int nthreads)
 735 {
 736         return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
 737                                      PERF_EVENT_IOC_ENABLE,
 738                                      0);
 739 }
 740
 741 int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
 742 {
 743         evsel->sample_id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
 744         if (evsel->sample_id == NULL)
 745                 return -ENOMEM;
 746
 747         evsel->id = zalloc(ncpus * nthreads * sizeof(u64));
 748         if (evsel->id == NULL) {
 749                 xyarray__delete(evsel->sample_id);
 750                 evsel->sample_id = NULL;
 751                 return -ENOMEM;
 752         }
 753
 754         return 0;
 755 }
 756
 757 void perf_evsel__reset_counts(struct perf_evsel *evsel, int ncpus)
 758 {
 759         memset(evsel->counts, 0, (sizeof(*evsel->counts) +
 760                                  (ncpus * sizeof(struct perf_counts_values))));
 761 }
 762
 763 int perf_evsel__alloc_counts(struct perf_evsel *evsel, int ncpus)
 764 {
 765         evsel->counts = zalloc((sizeof(*evsel->counts) +
 766                                 (ncpus * sizeof(struct perf_counts_values))));
 767         return evsel->counts != NULL ? 0 : -ENOMEM;
 768 }
 769
 770 void perf_evsel__free_fd(struct perf_evsel *evsel)
 771 {
 772         xyarray__delete(evsel->fd);
 773         evsel->fd = NULL;
 774 }
 775
 776 void perf_evsel__free_id(struct perf_evsel *evsel)
 777 {
 778         xyarray__delete(evsel->sample_id);
 779         evsel->sample_id = NULL;
 780         zfree(&evsel->id);
 781 }
 782
 783 void perf_evsel__close_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
 784 {
 785         int cpu, thread;
 786
 787         for (cpu = 0; cpu < ncpus; cpu++)
 788                 for (thread = 0; thread < nthreads; ++thread) {
 789                         close(FD(evsel, cpu, thread));
 790                         FD(evsel, cpu, thread) = -1;
 791                 }
 792 }
 793
 794 void perf_evsel__free_counts(struct perf_evsel *evsel)
 795 {
 796         zfree(&evsel->counts);
 797 }
 798
 799 void perf_evsel__exit(struct perf_evsel *evsel)
 800 {
 801         assert(list_empty(&evsel->node));
 802         perf_evsel__free_fd(evsel);
 803         perf_evsel__free_id(evsel);
 804 }
 805
 806 void perf_evsel__delete(struct perf_evsel *evsel)
 807 {
 808         perf_evsel__exit(evsel);
 809         close_cgroup(evsel->cgrp);
 810         zfree(&evsel->group_name);
 811         if (evsel->tp_format)
 812                 pevent_free_format(evsel->tp_format);
 813         zfree(&evsel->name);
 814         free(evsel);
 815 }
 816
 817 static inline void compute_deltas(struct perf_evsel *evsel,
 818                                   int cpu,
 819                                   struct perf_counts_values *count)
 820 {
 821         struct perf_counts_values tmp;
 822
 823         if (!evsel->prev_raw_counts)
 824                 return;
 825
 826         if (cpu == -1) {
 827                 tmp = evsel->prev_raw_counts->aggr;
 828                 evsel->prev_raw_counts->aggr = *count;
 829         } else {
 830                 tmp = evsel->prev_raw_counts->cpu[cpu];
 831                 evsel->prev_raw_counts->cpu[cpu] = *count;
 832         }
 833
 834         count->val = count->val - tmp.val;
 835         count->ena = count->ena - tmp.ena;
 836         count->run = count->run - tmp.run;
 837 }
 838
 839 int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
 840                               int cpu, int thread, bool scale)
 841 {
 842         struct perf_counts_values count;
 843         size_t nv = scale ? 3 : 1;
 844
 845         if (FD(evsel, cpu, thread) < 0)
 846                 return -EINVAL;
 847
 848         if (evsel->counts == NULL && perf_evsel__alloc_counts(evsel, cpu + 1) < 0)
 849                 return -ENOMEM;
 850
 851         if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) < 0)
 852                 return -errno;
 853
 854         compute_deltas(evsel, cpu, &count);
 855
 856         if (scale) {
 857                 if (count.run == 0)
 858                         count.val = 0;
 859                 else if (count.run < count.ena)
 860                         count.val = (u64)((double)count.val * count.ena / count.run + 0.5);
 861         } else
 862                 count.ena = count.run = 0;
 863
 864         evsel->counts->cpu[cpu] = count;
 865         return 0;
 866 }
 867
 868 int __perf_evsel__read(struct perf_evsel *evsel,
 869                        int ncpus, int nthreads, bool scale)
 870 {
 871         size_t nv = scale ? 3 : 1;
 872         int cpu, thread;
 873         struct perf_counts_values *aggr = &evsel->counts->aggr, count;
 874
 875         aggr->val = aggr->ena = aggr->run = 0;
 876
 877         for (cpu = 0; cpu < ncpus; cpu++) {
 878                 for (thread = 0; thread < nthreads; thread++) {
 879                         if (FD(evsel, cpu, thread) < 0)
 880                                 continue;
 881
 882                         if (readn(FD(evsel, cpu, thread),
 883                                   &count, nv * sizeof(u64)) < 0)
 884                                 return -errno;
 885
 886                         aggr->val += count.val;
 887                         if (scale) {
 888                                 aggr->ena += count.ena;
 889                                 aggr->run += count.run;
 890                         }
 891                 }
 892         }
 893
 894         compute_deltas(evsel, -1, aggr);
 895
 896         evsel->counts->scaled = 0;
 897         if (scale) {
 898                 if (aggr->run == 0) {
 899                         evsel->counts->scaled = -1;
 900                         aggr->val = 0;
 901                         return 0;
 902                 }
 903
 904                 if (aggr->run < aggr->ena) {
 905                         evsel->counts->scaled = 1;
 906                         aggr->val = (u64)((double)aggr->val * aggr->ena / aggr->run + 0.5);
 907                 }
 908         } else
 909                 aggr->ena = aggr->run = 0;
 910
 911         return 0;
 912 }
 913
 914 static int get_group_fd(struct perf_evsel *evsel, int cpu, int thread)
 915 {
 916         struct perf_evsel *leader = evsel->leader;
 917         int fd;
 918
 919         if (perf_evsel__is_group_leader(evsel))
 920                 return -1;
 921
 922         /*
 923          * Leader must be already processed/open,
 924          * if not it's a bug.
 925          */
 926         BUG_ON(!leader->fd);
 927
 928         fd = FD(leader, cpu, thread);
 929         BUG_ON(fd == -1);
 930
 931         return fd;
 932 }
 933
 934 #define __PRINT_ATTR(fmt, cast, field)  \
 935         fprintf(fp, "  %-19s "fmt"\n", #field, cast attr->field)
 936
 937 #define PRINT_ATTR_U32(field)  __PRINT_ATTR("%u" , , field)
 938 #define PRINT_ATTR_X32(field)  __PRINT_ATTR("%#x", , field)
 939 #define PRINT_ATTR_U64(field)  __PRINT_ATTR("%" PRIu64, (uint64_t), field)
 940 #define PRINT_ATTR_X64(field)  __PRINT_ATTR("%#"PRIx64, (uint64_t), field)
 941
 942 #define PRINT_ATTR2N(name1, field1, name2, field2)      \
 943         fprintf(fp, "  %-19s %u    %-19s %u\n",         \
 944         name1, attr->field1, name2, attr->field2)
 945
 946 #define PRINT_ATTR2(field1, field2) \
 947         PRINT_ATTR2N(#field1, field1, #field2, field2)
 948
 949 static size_t perf_event_attr__fprintf(struct perf_event_attr *attr, FILE *fp)
 950 {
 951         size_t ret = 0;
 952
 953         ret += fprintf(fp, "%.60s\n", graph_dotted_line);
 954         ret += fprintf(fp, "perf_event_attr:\n");
 955
 956         ret += PRINT_ATTR_U32(type);
 957         ret += PRINT_ATTR_U32(size);
 958         ret += PRINT_ATTR_X64(config);
 959         ret += PRINT_ATTR_U64(sample_period);
 960         ret += PRINT_ATTR_U64(sample_freq);
 961         ret += PRINT_ATTR_X64(sample_type);
 962         ret += PRINT_ATTR_X64(read_format);
 963
 964         ret += PRINT_ATTR2(disabled, inherit);
 965         ret += PRINT_ATTR2(pinned, exclusive);
 966         ret += PRINT_ATTR2(exclude_user, exclude_kernel);
 967         ret += PRINT_ATTR2(exclude_hv, exclude_idle);
 968         ret += PRINT_ATTR2(mmap, comm);
 969         ret += PRINT_ATTR2(mmap2, comm_exec);
 970         ret += PRINT_ATTR2(freq, inherit_stat);
 971         ret += PRINT_ATTR2(enable_on_exec, task);
 972         ret += PRINT_ATTR2(watermark, precise_ip);
 973         ret += PRINT_ATTR2(mmap_data, sample_id_all);
 974         ret += PRINT_ATTR2(exclude_host, exclude_guest);
 975         ret += PRINT_ATTR2N("excl.callchain_kern", exclude_callchain_kernel,
 976                             "excl.callchain_user", exclude_callchain_user);
 977
 978         ret += PRINT_ATTR_U32(wakeup_events);
 979         ret += PRINT_ATTR_U32(wakeup_watermark);
 980         ret += PRINT_ATTR_X32(bp_type);
 981         ret += PRINT_ATTR_X64(bp_addr);
 982         ret += PRINT_ATTR_X64(config1);
 983         ret += PRINT_ATTR_U64(bp_len);
 984         ret += PRINT_ATTR_X64(config2);
 985         ret += PRINT_ATTR_X64(branch_sample_type);
 986         ret += PRINT_ATTR_X64(sample_regs_user);
 987         ret += PRINT_ATTR_U32(sample_stack_user);
 988
 989         ret += fprintf(fp, "%.60s\n", graph_dotted_line);
 990
 991         return ret;
 992 }
 993
 994 static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
 995                               struct thread_map *threads)
 996 {
 997         int cpu, thread;
 998         unsigned long flags = PERF_FLAG_FD_CLOEXEC;
 999         int pid = -1, err;
1000         enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;
1001
1002         if (evsel->fd == NULL &&
1003             perf_evsel__alloc_fd(evsel, cpus->nr, threads->nr) < 0)
1004                 return -ENOMEM;
1005
1006         if (evsel->cgrp) {
1007                 flags |= PERF_FLAG_PID_CGROUP;
1008                 pid = evsel->cgrp->fd;
1009         }
1010
1011 fallback_missing_features:
1012         if (perf_missing_features.cloexec)
1013                 flags &= ~(unsigned long)PERF_FLAG_FD_CLOEXEC;
1014         if (perf_missing_features.mmap2)
1015                 evsel->attr.mmap2 = 0;
1016         if (perf_missing_features.exclude_guest)
1017                 evsel->attr.exclude_guest = evsel->attr.exclude_host = 0;
1018 retry_sample_id:
1019         if (perf_missing_features.sample_id_all)
1020                 evsel->attr.sample_id_all = 0;
1021
1022         if (verbose >= 2)
1023                 perf_event_attr__fprintf(&evsel->attr, stderr);
1024
1025         for (cpu = 0; cpu < cpus->nr; cpu++) {
1026
1027                 for (thread = 0; thread < threads->nr; thread++) {
1028                         int group_fd;
1029
1030                         if (!evsel->cgrp)
1031                                 pid = threads->map[thread];
1032
1033                         group_fd = get_group_fd(evsel, cpu, thread);
1034 retry_open:
1035                         pr_debug2("sys_perf_event_open: pid %d  cpu %d  group_fd %d  flags %#lx\n",
1036                                   pid, cpus->map[cpu], group_fd, flags);
1037
1038                         FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr,
1039                                                                      pid,
1040                                                                      cpus->map[cpu],
1041                                                                      group_fd, flags);
1042                         if (FD(evsel, cpu, thread) < 0) {
1043                                 err = -errno;
1044                                 pr_debug2("sys_perf_event_open failed, error %d\n",
1045                                           err);
1046                                 goto try_fallback;
1047                         }
1048                         set_rlimit = NO_CHANGE;
1049                 }
1050         }
1051
1052         return 0;
1053
1054 try_fallback:
1055         /*
1056          * perf stat needs between 5 and 22 fds per CPU. When we run out
1057          * of them try to increase the limits.
1058          */
1059         if (err == -EMFILE && set_rlimit < INCREASED_MAX) {
1060                 struct rlimit l;
1061                 int old_errno = errno;
1062
1063                 if (getrlimit(RLIMIT_NOFILE, &l) == 0) {
1064                         if (set_rlimit == NO_CHANGE)
1065                                 l.rlim_cur = l.rlim_max;
1066                         else {
1067                                 l.rlim_cur = l.rlim_max + 1000;
1068                                 l.rlim_max = l.rlim_cur;
1069                         }
1070                         if (setrlimit(RLIMIT_NOFILE, &l) == 0) {
1071                                 set_rlimit++;
1072                                 errno = old_errno;
1073                                 goto retry_open;
1074                         }
1075                 }
1076                 errno = old_errno;
1077         }
1078
1079         if (err != -EINVAL || cpu > 0 || thread > 0)
1080                 goto out_close;
1081
1082         if (!perf_missing_features.cloexec && (flags & PERF_FLAG_FD_CLOEXEC)) {
1083                 perf_missing_features.cloexec = true;
1084                 goto fallback_missing_features;
1085         } else if (!perf_missing_features.mmap2 && evsel->attr.mmap2) {
1086                 perf_missing_features.mmap2 = true;
1087                 goto fallback_missing_features;
1088         } else if (!perf_missing_features.exclude_guest &&
1089                    (evsel->attr.exclude_guest || evsel->attr.exclude_host)) {
1090                 perf_missing_features.exclude_guest = true;
1091                 goto fallback_missing_features;
1092         } else if (!perf_missing_features.sample_id_all) {
1093                 perf_missing_features.sample_id_all = true;
1094                 goto retry_sample_id;
1095         }
1096
1097 out_close:
1098         do {
1099                 while (--thread >= 0) {
1100                         close(FD(evsel, cpu, thread));
1101                         FD(evsel, cpu, thread) = -1;
1102                 }
1103                 thread = threads->nr;
1104         } while (--cpu >= 0);
1105         return err;
1106 }
1107
1108 void perf_evsel__close(struct perf_evsel *evsel, int ncpus, int nthreads)
1109 {
1110         if (evsel->fd == NULL)
1111                 return;
1112
1113         perf_evsel__close_fd(evsel, ncpus, nthreads);
1114         perf_evsel__free_fd(evsel);
1115 }
1116
1117 static struct {
1118         struct cpu_map map;
1119         int cpus[1];
1120 } empty_cpu_map = {
1121         .map.nr = 1,
1122         .cpus   = { -1, },
1123 };
1124
1125 static struct {
1126         struct thread_map map;
1127         int threads[1];
1128 } empty_thread_map = {
1129         .map.nr  = 1,
1130         .threads = { -1, },
1131 };
1132
1133 int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1134                      struct thread_map *threads)
1135 {
1136         if (cpus == NULL) {
1137                 /* Work around old compiler warnings about strict aliasing */
1138                 cpus = &empty_cpu_map.map;
1139         }
1140
1141         if (threads == NULL)
1142                 threads = &empty_thread_map.map;
1143
1144         return __perf_evsel__open(evsel, cpus, threads);
1145 }
1146
1147 int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
1148                              struct cpu_map *cpus)
1149 {
1150         return __perf_evsel__open(evsel, cpus, &empty_thread_map.map);
1151 }
1152
1153 int perf_evsel__open_per_thread(struct perf_evsel *evsel,
1154                                 struct thread_map *threads)
1155 {
1156         return __perf_evsel__open(evsel, &empty_cpu_map.map, threads);
1157 }
1158
1159 static int perf_evsel__parse_id_sample(const struct perf_evsel *evsel,
1160                                        const union perf_event *event,
1161                                        struct perf_sample *sample)
1162 {
1163         u64 type = evsel->attr.sample_type;
1164         const u64 *array = event->sample.array;
1165         bool swapped = evsel->needs_swap;
1166         union u64_swap u;
1167
1168         array += ((event->header.size -
1169                    sizeof(event->header)) / sizeof(u64)) - 1;
1170
1171         if (type & PERF_SAMPLE_IDENTIFIER) {
1172                 sample->id = *array;
1173                 array--;
1174         }
1175
1176         if (type & PERF_SAMPLE_CPU) {
1177                 u.val64 = *array;
1178                 if (swapped) {
1179                         /* undo swap of u64, then swap on individual u32s */
1180                         u.val64 = bswap_64(u.val64);
1181                         u.val32[0] = bswap_32(u.val32[0]);
1182                 }
1183
1184                 sample->cpu = u.val32[0];
1185                 array--;
1186         }
1187
1188         if (type & PERF_SAMPLE_STREAM_ID) {
1189                 sample->stream_id = *array;
1190                 array--;
1191         }
1192
1193         if (type & PERF_SAMPLE_ID) {
1194                 sample->id = *array;
1195                 array--;
1196         }
1197
1198         if (type & PERF_SAMPLE_TIME) {
1199                 sample->time = *array;
1200                 array--;
1201         }
1202
1203         if (type & PERF_SAMPLE_TID) {
1204                 u.val64 = *array;
1205                 if (swapped) {
1206                         /* undo swap of u64, then swap on individual u32s */
1207                         u.val64 = bswap_64(u.val64);
1208                         u.val32[0] = bswap_32(u.val32[0]);
1209                         u.val32[1] = bswap_32(u.val32[1]);
1210                 }
1211
1212                 sample->pid = u.val32[0];
1213                 sample->tid = u.val32[1];
1214                 array--;
1215         }
1216
1217         return 0;
1218 }
1219
1220 static inline bool overflow(const void *endp, u16 max_size, const void *offset,
1221                             u64 size)
1222 {
1223         return size > max_size || offset + size > endp;
1224 }
1225
1226 #define OVERFLOW_CHECK(offset, size, max_size)                          \
1227         do {                                                            \
1228                 if (overflow(endp, (max_size), (offset), (size)))       \
1229                         return -EFAULT;                                 \
1230         } while (0)
1231
1232 #define OVERFLOW_CHECK_u64(offset) \
1233         OVERFLOW_CHECK(offset, sizeof(u64), sizeof(u64))
1234
1235 int perf_evsel__parse_sample(struct perf_evsel *evsel, union perf_event *event,
1236                              struct perf_sample *data)
1237 {
1238         u64 type = evsel->attr.sample_type;
1239         bool swapped = evsel->needs_swap;
1240         const u64 *array;
1241         u16 max_size = event->header.size;
1242         const void *endp = (void *)event + max_size;
1243         u64 sz;
1244
1245         /*
1246          * used for cross-endian analysis. See git commit 65014ab3
1247          * for why this goofiness is needed.
1248          */
1249         union u64_swap u;
1250
1251         memset(data, 0, sizeof(*data));
1252         data->cpu = data->pid = data->tid = -1;
1253         data->stream_id = data->id = data->time = -1ULL;
1254         data->period = evsel->attr.sample_period;
1255         data->weight = 0;
1256
1257         if (event->header.type != PERF_RECORD_SAMPLE) {
1258                 if (!evsel->attr.sample_id_all)
1259                         return 0;
1260                 return perf_evsel__parse_id_sample(evsel, event, data);
1261         }
1262
1263         array = event->sample.array;
1264
1265         /*
1266          * The evsel's sample_size is based on PERF_SAMPLE_MASK which includes
1267          * up to PERF_SAMPLE_PERIOD.  After that overflow() must be used to
1268          * check the format does not go past the end of the event.
1269          */
1270         if (evsel->sample_size + sizeof(event->header) > event->header.size)
1271                 return -EFAULT;
1272
1273         data->id = -1ULL;
1274         if (type & PERF_SAMPLE_IDENTIFIER) {
1275                 data->id = *array;
1276                 array++;
1277         }
1278
1279         if (type & PERF_SAMPLE_IP) {
1280                 data->ip = *array;
1281                 array++;
1282         }
1283
1284         if (type & PERF_SAMPLE_TID) {
1285                 u.val64 = *array;
1286                 if (swapped) {
1287                         /* undo swap of u64, then swap on individual u32s */
1288                         u.val64 = bswap_64(u.val64);
1289                         u.val32[0] = bswap_32(u.val32[0]);
1290                         u.val32[1] = bswap_32(u.val32[1]);
1291                 }
1292
1293                 data->pid = u.val32[0];
1294                 data->tid = u.val32[1];
1295                 array++;
1296         }
1297
1298         if (type & PERF_SAMPLE_TIME) {
1299                 data->time = *array;
1300                 array++;
1301         }
1302
1303         data->addr = 0;
1304         if (type & PERF_SAMPLE_ADDR) {
1305                 data->addr = *array;
1306                 array++;
1307         }
1308
1309         if (type & PERF_SAMPLE_ID) {
1310                 data->id = *array;
1311                 array++;
1312         }
1313
1314         if (type & PERF_SAMPLE_STREAM_ID) {
1315                 data->stream_id = *array;
1316                 array++;
1317         }
1318
1319         if (type & PERF_SAMPLE_CPU) {
1320
1321                 u.val64 = *array;
1322                 if (swapped) {
1323                         /* undo swap of u64, then swap on individual u32s */
1324                         u.val64 = bswap_64(u.val64);
1325                         u.val32[0] = bswap_32(u.val32[0]);
1326                 }
1327
1328                 data->cpu = u.val32[0];
1329                 array++;
1330         }
1331
1332         if (type & PERF_SAMPLE_PERIOD) {
1333                 data->period = *array;
1334                 array++;
1335         }
1336
1337         if (type & PERF_SAMPLE_READ) {
1338                 u64 read_format = evsel->attr.read_format;
1339
1340                 OVERFLOW_CHECK_u64(array);
1341                 if (read_format & PERF_FORMAT_GROUP)
1342                         data->read.group.nr = *array;
1343                 else
1344                         data->read.one.value = *array;
1345
1346                 array++;
1347
1348                 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1349                         OVERFLOW_CHECK_u64(array);
1350                         data->read.time_enabled = *array;
1351                         array++;
1352                 }
1353
1354                 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1355                         OVERFLOW_CHECK_u64(array);
1356                         data->read.time_running = *array;
1357                         array++;
1358                 }
1359
1360                 /* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1361                 if (read_format & PERF_FORMAT_GROUP) {
1362                         const u64 max_group_nr = UINT64_MAX /
1363                                         sizeof(struct sample_read_value);
1364
1365                         if (data->read.group.nr > max_group_nr)
1366                                 return -EFAULT;
1367                         sz = data->read.group.nr *
1368                              sizeof(struct sample_read_value);
1369                         OVERFLOW_CHECK(array, sz, max_size);
1370                         data->read.group.values =
1371                                         (struct sample_read_value *)array;
1372                         array = (void *)array + sz;
1373                 } else {
1374                         OVERFLOW_CHECK_u64(array);
1375                         data->read.one.id = *array;
1376                         array++;
1377                 }
1378         }
1379
1380         if (type & PERF_SAMPLE_CALLCHAIN) {
1381                 const u64 max_callchain_nr = UINT64_MAX / sizeof(u64);
1382
1383                 OVERFLOW_CHECK_u64(array);
1384                 data->callchain = (struct ip_callchain *)array++;
1385                 if (data->callchain->nr > max_callchain_nr)
1386                         return -EFAULT;
1387                 sz = data->callchain->nr * sizeof(u64);
1388                 OVERFLOW_CHECK(array, sz, max_size);
1389                 array = (void *)array + sz;
1390         }
1391
1392         if (type & PERF_SAMPLE_RAW) {
1393                 OVERFLOW_CHECK_u64(array);
1394                 u.val64 = *array;
1395                 if (WARN_ONCE(swapped,
1396                               "Endianness of raw data not corrected!\n")) {
1397                         /* undo swap of u64, then swap on individual u32s */
1398                         u.val64 = bswap_64(u.val64);
1399                         u.val32[0] = bswap_32(u.val32[0]);
1400                         u.val32[1] = bswap_32(u.val32[1]);
1401                 }
1402                 data->raw_size = u.val32[0];
1403                 array = (void *)array + sizeof(u32);
1404
1405                 OVERFLOW_CHECK(array, data->raw_size, max_size);
1406                 data->raw_data = (void *)array;
1407                 array = (void *)array + data->raw_size;
1408         }
1409
1410         if (type & PERF_SAMPLE_BRANCH_STACK) {
1411                 const u64 max_branch_nr = UINT64_MAX /
1412                                           sizeof(struct branch_entry);
1413
1414                 OVERFLOW_CHECK_u64(array);
1415                 data->branch_stack = (struct branch_stack *)array++;
1416
1417                 if (data->branch_stack->nr > max_branch_nr)
1418                         return -EFAULT;
1419                 sz = data->branch_stack->nr * sizeof(struct branch_entry);
1420                 OVERFLOW_CHECK(array, sz, max_size);
1421                 array = (void *)array + sz;
1422         }
1423
1424         if (type & PERF_SAMPLE_REGS_USER) {
1425                 OVERFLOW_CHECK_u64(array);
1426                 data->user_regs.abi = *array;
1427                 array++;
1428
1429                 if (data->user_regs.abi) {
1430                         u64 mask = evsel->attr.sample_regs_user;
1431
1432                         sz = hweight_long(mask) * sizeof(u64);
1433                         OVERFLOW_CHECK(array, sz, max_size);
1434                         data->user_regs.mask = mask;
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                         if (WARN_ONCE(data->user_stack.size > sz,
1456                                       "user stack dump failure\n"))
1457                                 return -EFAULT;
1458                 }
1459         }
1460
1461         data->weight = 0;
1462         if (type & PERF_SAMPLE_WEIGHT) {
1463                 OVERFLOW_CHECK_u64(array);
1464                 data->weight = *array;
1465                 array++;
1466         }
1467
1468         data->data_src = PERF_MEM_DATA_SRC_NONE;
1469         if (type & PERF_SAMPLE_DATA_SRC) {
1470                 OVERFLOW_CHECK_u64(array);
1471                 data->data_src = *array;
1472                 array++;
1473         }
1474
1475         data->transaction = 0;
1476         if (type & PERF_SAMPLE_TRANSACTION) {
1477                 OVERFLOW_CHECK_u64(array);
1478                 data->transaction = *array;
1479                 array++;
1480         }
1481
1482         return 0;
1483 }
1484
1485 size_t perf_event__sample_event_size(const struct perf_sample *sample, u64 type,
1486                                      u64 read_format)
1487 {
1488         size_t sz, result = sizeof(struct sample_event);
1489
1490         if (type & PERF_SAMPLE_IDENTIFIER)
1491                 result += sizeof(u64);
1492
1493         if (type & PERF_SAMPLE_IP)
1494                 result += sizeof(u64);
1495
1496         if (type & PERF_SAMPLE_TID)
1497                 result += sizeof(u64);
1498
1499         if (type & PERF_SAMPLE_TIME)
1500                 result += sizeof(u64);
1501
1502         if (type & PERF_SAMPLE_ADDR)
1503                 result += sizeof(u64);
1504
1505         if (type & PERF_SAMPLE_ID)
1506                 result += sizeof(u64);
1507
1508         if (type & PERF_SAMPLE_STREAM_ID)
1509                 result += sizeof(u64);
1510
1511         if (type & PERF_SAMPLE_CPU)
1512                 result += sizeof(u64);
1513
1514         if (type & PERF_SAMPLE_PERIOD)
1515                 result += sizeof(u64);
1516
1517         if (type & PERF_SAMPLE_READ) {
1518                 result += sizeof(u64);
1519                 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
1520                         result += sizeof(u64);
1521                 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
1522                         result += sizeof(u64);
1523                 /* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1524                 if (read_format & PERF_FORMAT_GROUP) {
1525                         sz = sample->read.group.nr *
1526                              sizeof(struct sample_read_value);
1527                         result += sz;
1528                 } else {
1529                         result += sizeof(u64);
1530                 }
1531         }
1532
1533         if (type & PERF_SAMPLE_CALLCHAIN) {
1534                 sz = (sample->callchain->nr + 1) * sizeof(u64);
1535                 result += sz;
1536         }
1537
1538         if (type & PERF_SAMPLE_RAW) {
1539                 result += sizeof(u32);
1540                 result += sample->raw_size;
1541         }
1542
1543         if (type & PERF_SAMPLE_BRANCH_STACK) {
1544                 sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1545                 sz += sizeof(u64);
1546                 result += sz;
1547         }
1548
1549         if (type & PERF_SAMPLE_REGS_USER) {
1550                 if (sample->user_regs.abi) {
1551                         result += sizeof(u64);
1552                         sz = hweight_long(sample->user_regs.mask) * sizeof(u64);
1553                         result += sz;
1554                 } else {
1555                         result += sizeof(u64);
1556                 }
1557         }
1558
1559         if (type & PERF_SAMPLE_STACK_USER) {
1560                 sz = sample->user_stack.size;
1561                 result += sizeof(u64);
1562                 if (sz) {
1563                         result += sz;
1564                         result += sizeof(u64);
1565                 }
1566         }
1567
1568         if (type & PERF_SAMPLE_WEIGHT)
1569                 result += sizeof(u64);
1570
1571         if (type & PERF_SAMPLE_DATA_SRC)
1572                 result += sizeof(u64);
1573
1574         if (type & PERF_SAMPLE_TRANSACTION)
1575                 result += sizeof(u64);
1576
1577         return result;
1578 }
1579
1580 int perf_event__synthesize_sample(union perf_event *event, u64 type,
1581                                   u64 read_format,
1582                                   const struct perf_sample *sample,
1583                                   bool swapped)
1584 {
1585         u64 *array;
1586         size_t sz;
1587         /*
1588          * used for cross-endian analysis. See git commit 65014ab3
1589          * for why this goofiness is needed.
1590          */
1591         union u64_swap u;
1592
1593         array = event->sample.array;
1594
1595         if (type & PERF_SAMPLE_IDENTIFIER) {
1596                 *array = sample->id;
1597                 array++;
1598         }
1599
1600         if (type & PERF_SAMPLE_IP) {
1601                 *array = sample->ip;
1602                 array++;
1603         }
1604
1605         if (type & PERF_SAMPLE_TID) {
1606                 u.val32[0] = sample->pid;
1607                 u.val32[1] = sample->tid;
1608                 if (swapped) {
1609                         /*
1610                          * Inverse of what is done in perf_evsel__parse_sample
1611                          */
1612                         u.val32[0] = bswap_32(u.val32[0]);
1613                         u.val32[1] = bswap_32(u.val32[1]);
1614                         u.val64 = bswap_64(u.val64);
1615                 }
1616
1617                 *array = u.val64;
1618                 array++;
1619         }
1620
1621         if (type & PERF_SAMPLE_TIME) {
1622                 *array = sample->time;
1623                 array++;
1624         }
1625
1626         if (type & PERF_SAMPLE_ADDR) {
1627                 *array = sample->addr;
1628                 array++;
1629         }
1630
1631         if (type & PERF_SAMPLE_ID) {
1632                 *array = sample->id;
1633                 array++;
1634         }
1635
1636         if (type & PERF_SAMPLE_STREAM_ID) {
1637                 *array = sample->stream_id;
1638                 array++;
1639         }
1640
1641         if (type & PERF_SAMPLE_CPU) {
1642                 u.val32[0] = sample->cpu;
1643                 if (swapped) {
1644                         /*
1645                          * Inverse of what is done in perf_evsel__parse_sample
1646                          */
1647                         u.val32[0] = bswap_32(u.val32[0]);
1648                         u.val64 = bswap_64(u.val64);
1649                 }
1650                 *array = u.val64;
1651                 array++;
1652         }
1653
1654         if (type & PERF_SAMPLE_PERIOD) {
1655                 *array = sample->period;
1656                 array++;
1657         }
1658
1659         if (type & PERF_SAMPLE_READ) {
1660                 if (read_format & PERF_FORMAT_GROUP)
1661                         *array = sample->read.group.nr;
1662                 else
1663                         *array = sample->read.one.value;
1664                 array++;
1665
1666                 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1667                         *array = sample->read.time_enabled;
1668                         array++;
1669                 }
1670
1671                 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1672                         *array = sample->read.time_running;
1673                         array++;
1674                 }
1675
1676                 /* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1677                 if (read_format & PERF_FORMAT_GROUP) {
1678                         sz = sample->read.group.nr *
1679                              sizeof(struct sample_read_value);
1680                         memcpy(array, sample->read.group.values, sz);
1681                         array = (void *)array + sz;
1682                 } else {
1683                         *array = sample->read.one.id;
1684                         array++;
1685                 }
1686         }
1687
1688         if (type & PERF_SAMPLE_CALLCHAIN) {
1689                 sz = (sample->callchain->nr + 1) * sizeof(u64);
1690                 memcpy(array, sample->callchain, sz);
1691                 array = (void *)array + sz;
1692         }
1693
1694         if (type & PERF_SAMPLE_RAW) {
1695                 u.val32[0] = sample->raw_size;
1696                 if (WARN_ONCE(swapped,
1697                               "Endianness of raw data not corrected!\n")) {
1698                         /*
1699                          * Inverse of what is done in perf_evsel__parse_sample
1700                          */
1701                         u.val32[0] = bswap_32(u.val32[0]);
1702                         u.val32[1] = bswap_32(u.val32[1]);
1703                         u.val64 = bswap_64(u.val64);
1704                 }
1705                 *array = u.val64;
1706                 array = (void *)array + sizeof(u32);
1707
1708                 memcpy(array, sample->raw_data, sample->raw_size);
1709                 array = (void *)array + sample->raw_size;
1710         }
1711
1712         if (type & PERF_SAMPLE_BRANCH_STACK) {
1713                 sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1714                 sz += sizeof(u64);
1715                 memcpy(array, sample->branch_stack, sz);
1716                 array = (void *)array + sz;
1717         }
1718
1719         if (type & PERF_SAMPLE_REGS_USER) {
1720                 if (sample->user_regs.abi) {
1721                         *array++ = sample->user_regs.abi;
1722                         sz = hweight_long(sample->user_regs.mask) * sizeof(u64);
1723                         memcpy(array, sample->user_regs.regs, sz);
1724                         array = (void *)array + sz;
1725                 } else {
1726                         *array++ = 0;
1727                 }
1728         }
1729
1730         if (type & PERF_SAMPLE_STACK_USER) {
1731                 sz = sample->user_stack.size;
1732                 *array++ = sz;
1733                 if (sz) {
1734                         memcpy(array, sample->user_stack.data, sz);
1735                         array = (void *)array + sz;
1736                         *array++ = sz;
1737                 }
1738         }
1739
1740         if (type & PERF_SAMPLE_WEIGHT) {
1741                 *array = sample->weight;
1742                 array++;
1743         }
1744
1745         if (type & PERF_SAMPLE_DATA_SRC) {
1746                 *array = sample->data_src;
1747                 array++;
1748         }
1749
1750         if (type & PERF_SAMPLE_TRANSACTION) {
1751                 *array = sample->transaction;
1752                 array++;
1753         }
1754
1755         return 0;
1756 }
1757
1758 struct format_field *perf_evsel__field(struct perf_evsel *evsel, const char *name)
1759 {
1760         return pevent_find_field(evsel->tp_format, name);
1761 }
1762
1763 void *perf_evsel__rawptr(struct perf_evsel *evsel, struct perf_sample *sample,
1764                          const char *name)
1765 {
1766         struct format_field *field = perf_evsel__field(evsel, name);
1767         int offset;
1768
1769         if (!field)
1770                 return NULL;
1771
1772         offset = field->offset;
1773
1774         if (field->flags & FIELD_IS_DYNAMIC) {
1775                 offset = *(int *)(sample->raw_data + field->offset);
1776                 offset &= 0xffff;
1777         }
1778
1779         return sample->raw_data + offset;
1780 }
1781
1782 u64 perf_evsel__intval(struct perf_evsel *evsel, struct perf_sample *sample,
1783                        const char *name)
1784 {
1785         struct format_field *field = perf_evsel__field(evsel, name);
1786         void *ptr;
1787         u64 value;
1788
1789         if (!field)
1790                 return 0;
1791
1792         ptr = sample->raw_data + field->offset;
1793
1794         switch (field->size) {
1795         case 1:
1796                 return *(u8 *)ptr;
1797         case 2:
1798                 value = *(u16 *)ptr;
1799                 break;
1800         case 4:
1801                 value = *(u32 *)ptr;
1802                 break;
1803         case 8:
1804                 value = *(u64 *)ptr;
1805                 break;
1806         default:
1807                 return 0;
1808         }
1809
1810         if (!evsel->needs_swap)
1811                 return value;
1812
1813         switch (field->size) {
1814         case 2:
1815                 return bswap_16(value);
1816         case 4:
1817                 return bswap_32(value);
1818         case 8:
1819                 return bswap_64(value);
1820         default:
1821                 return 0;
1822         }
1823
1824         return 0;
1825 }
1826
1827 static int comma_fprintf(FILE *fp, bool *first, const char *fmt, ...)
1828 {
1829         va_list args;
1830         int ret = 0;
1831
1832         if (!*first) {
1833                 ret += fprintf(fp, ",");
1834         } else {
1835                 ret += fprintf(fp, ":");
1836                 *first = false;
1837         }
1838
1839         va_start(args, fmt);
1840         ret += vfprintf(fp, fmt, args);
1841         va_end(args);
1842         return ret;
1843 }
1844
1845 static int __if_fprintf(FILE *fp, bool *first, const char *field, u64 value)
1846 {
1847         if (value == 0)
1848                 return 0;
1849
1850         return comma_fprintf(fp, first, " %s: %" PRIu64, field, value);
1851 }
1852
1853 #define if_print(field) printed += __if_fprintf(fp, &first, #field, evsel->attr.field)
1854
1855 struct bit_names {
1856         int bit;
1857         const char *name;
1858 };
1859
1860 static int bits__fprintf(FILE *fp, const char *field, u64 value,
1861                          struct bit_names *bits, bool *first)
1862 {
1863         int i = 0, printed = comma_fprintf(fp, first, " %s: ", field);
1864         bool first_bit = true;
1865
1866         do {
1867                 if (value & bits[i].bit) {
1868                         printed += fprintf(fp, "%s%s", first_bit ? "" : "|", bits[i].name);
1869                         first_bit = false;
1870                 }
1871         } while (bits[++i].name != NULL);
1872
1873         return printed;
1874 }
1875
1876 static int sample_type__fprintf(FILE *fp, bool *first, u64 value)
1877 {
1878 #define bit_name(n) { PERF_SAMPLE_##n, #n }
1879         struct bit_names bits[] = {
1880                 bit_name(IP), bit_name(TID), bit_name(TIME), bit_name(ADDR),
1881                 bit_name(READ), bit_name(CALLCHAIN), bit_name(ID), bit_name(CPU),
1882                 bit_name(PERIOD), bit_name(STREAM_ID), bit_name(RAW),
1883                 bit_name(BRANCH_STACK), bit_name(REGS_USER), bit_name(STACK_USER),
1884                 bit_name(IDENTIFIER),
1885                 { .name = NULL, }
1886         };
1887 #undef bit_name
1888         return bits__fprintf(fp, "sample_type", value, bits, first);
1889 }
1890
1891 static int read_format__fprintf(FILE *fp, bool *first, u64 value)
1892 {
1893 #define bit_name(n) { PERF_FORMAT_##n, #n }
1894         struct bit_names bits[] = {
1895                 bit_name(TOTAL_TIME_ENABLED), bit_name(TOTAL_TIME_RUNNING),
1896                 bit_name(ID), bit_name(GROUP),
1897                 { .name = NULL, }
1898         };
1899 #undef bit_name
1900         return bits__fprintf(fp, "read_format", value, bits, first);
1901 }
1902
1903 int perf_evsel__fprintf(struct perf_evsel *evsel,
1904                         struct perf_attr_details *details, FILE *fp)
1905 {
1906         bool first = true;
1907         int printed = 0;
1908
1909         if (details->event_group) {
1910                 struct perf_evsel *pos;
1911
1912                 if (!perf_evsel__is_group_leader(evsel))
1913                         return 0;
1914
1915                 if (evsel->nr_members > 1)
1916                         printed += fprintf(fp, "%s{", evsel->group_name ?: "");
1917
1918                 printed += fprintf(fp, "%s", perf_evsel__name(evsel));
1919                 for_each_group_member(pos, evsel)
1920                         printed += fprintf(fp, ",%s", perf_evsel__name(pos));
1921
1922                 if (evsel->nr_members > 1)
1923                         printed += fprintf(fp, "}");
1924                 goto out;
1925         }
1926
1927         printed += fprintf(fp, "%s", perf_evsel__name(evsel));
1928
1929         if (details->verbose || details->freq) {
1930                 printed += comma_fprintf(fp, &first, " sample_freq=%" PRIu64,
1931                                          (u64)evsel->attr.sample_freq);
1932         }
1933
1934         if (details->verbose) {
1935                 if_print(type);
1936                 if_print(config);
1937                 if_print(config1);
1938                 if_print(config2);
1939                 if_print(size);
1940                 printed += sample_type__fprintf(fp, &first, evsel->attr.sample_type);
1941                 if (evsel->attr.read_format)
1942                         printed += read_format__fprintf(fp, &first, evsel->attr.read_format);
1943                 if_print(disabled);
1944                 if_print(inherit);
1945                 if_print(pinned);
1946                 if_print(exclusive);
1947                 if_print(exclude_user);
1948                 if_print(exclude_kernel);
1949                 if_print(exclude_hv);
1950                 if_print(exclude_idle);
1951                 if_print(mmap);
1952                 if_print(mmap2);
1953                 if_print(comm);
1954                 if_print(comm_exec);
1955                 if_print(freq);
1956                 if_print(inherit_stat);
1957                 if_print(enable_on_exec);
1958                 if_print(task);
1959                 if_print(watermark);
1960                 if_print(precise_ip);
1961                 if_print(mmap_data);
1962                 if_print(sample_id_all);
1963                 if_print(exclude_host);
1964                 if_print(exclude_guest);
1965                 if_print(__reserved_1);
1966                 if_print(wakeup_events);
1967                 if_print(bp_type);
1968                 if_print(branch_sample_type);
1969         }
1970 out:
1971         fputc('\n', fp);
1972         return ++printed;
1973 }
1974
1975 bool perf_evsel__fallback(struct perf_evsel *evsel, int err,
1976                           char *msg, size_t msgsize)
1977 {
1978         if ((err == ENOENT || err == ENXIO || err == ENODEV) &&
1979             evsel->attr.type   == PERF_TYPE_HARDWARE &&
1980             evsel->attr.config == PERF_COUNT_HW_CPU_CYCLES) {
1981                 /*
1982                  * If it's cycles then fall back to hrtimer based
1983                  * cpu-clock-tick sw counter, which is always available even if
1984                  * no PMU support.
1985                  *
1986                  * PPC returns ENXIO until 2.6.37 (behavior changed with commit
1987                  * b0a873e).
1988                  */
1989                 scnprintf(msg, msgsize, "%s",
1990 "The cycles event is not supported, trying to fall back to cpu-clock-ticks");
1991
1992                 evsel->attr.type   = PERF_TYPE_SOFTWARE;
1993                 evsel->attr.config = PERF_COUNT_SW_CPU_CLOCK;
1994
1995                 zfree(&evsel->name);
1996                 return true;
1997         }
1998
1999         return false;
2000 }
2001
2002 int perf_evsel__open_strerror(struct perf_evsel *evsel, struct target *target,
2003                               int err, char *msg, size_t size)
2004 {
2005         switch (err) {
2006         case EPERM:
2007         case EACCES:
2008                 return scnprintf(msg, size,
2009                  "You may not have permission to collect %sstats.\n"
2010                  "Consider tweaking /proc/sys/kernel/perf_event_paranoid:\n"
2011                  " -1 - Not paranoid at all\n"
2012                  "  0 - Disallow raw tracepoint access for unpriv\n"
2013                  "  1 - Disallow cpu events for unpriv\n"
2014                  "  2 - Disallow kernel profiling for unpriv",
2015                                  target->system_wide ? "system-wide " : "");
2016         case ENOENT:
2017                 return scnprintf(msg, size, "The %s event is not supported.",
2018                                  perf_evsel__name(evsel));
2019         case EMFILE:
2020                 return scnprintf(msg, size, "%s",
2021                          "Too many events are opened.\n"
2022                          "Try again after reducing the number of events.");
2023         case ENODEV:
2024                 if (target->cpu_list)
2025                         return scnprintf(msg, size, "%s",
2026          "No such device - did you specify an out-of-range profile CPU?\n");
2027                 break;
2028         case EOPNOTSUPP:
2029                 if (evsel->attr.precise_ip)
2030                         return scnprintf(msg, size, "%s",
2031         "\'precise\' request may not be supported. Try removing 'p' modifier.");
2032 #if defined(__i386__) || defined(__x86_64__)
2033                 if (evsel->attr.type == PERF_TYPE_HARDWARE)
2034                         return scnprintf(msg, size, "%s",
2035         "No hardware sampling interrupt available.\n"
2036         "No APIC? If so then you can boot the kernel with the \"lapic\" boot parameter to force-enable it.");
2037 #endif
2038                 break;
2039         default:
2040                 break;
2041         }
2042
2043         return scnprintf(msg, size,
2044         "The sys_perf_event_open() syscall returned with %d (%s) for event (%s).  \n"
2045         "/bin/dmesg may provide additional information.\n"
2046         "No CONFIG_PERF_EVENTS=y kernel support configured?\n",
2047                          err, strerror(err), perf_evsel__name(evsel));
2048 }