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 } 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 static void
 504 perf_evsel__config_callgraph(struct perf_evsel *evsel,
 505                              struct record_opts *opts)
 506 {
 507         bool function = perf_evsel__is_function_event(evsel);
 508         struct perf_event_attr *attr = &evsel->attr;
 509
 510         perf_evsel__set_sample_bit(evsel, CALLCHAIN);
 511
 512         if (opts->call_graph == CALLCHAIN_DWARF) {
 513                 if (!function) {
 514                         perf_evsel__set_sample_bit(evsel, REGS_USER);
 515                         perf_evsel__set_sample_bit(evsel, STACK_USER);
 516                         attr->sample_regs_user = PERF_REGS_MASK;
 517                         attr->sample_stack_user = opts->stack_dump_size;
 518                         attr->exclude_callchain_user = 1;
 519                 } else {
 520                         pr_info("Cannot use DWARF unwind for function trace event,"
 521                                 " falling back to framepointers.\n");
 522                 }
 523         }
 524
 525         if (function) {
 526                 pr_info("Disabling user space callchains for function trace event.\n");
 527                 attr->exclude_callchain_user = 1;
 528         }
 529 }
 530
 531 /*
 532  * The enable_on_exec/disabled value strategy:
 533  *
 534  *  1) For any type of traced program:
 535  *    - all independent events and group leaders are disabled
 536  *    - all group members are enabled
 537  *
 538  *     Group members are ruled by group leaders. They need to
 539  *     be enabled, because the group scheduling relies on that.
 540  *
 541  *  2) For traced programs executed by perf:
 542  *     - all independent events and group leaders have
 543  *       enable_on_exec set
 544  *     - we don't specifically enable or disable any event during
 545  *       the record command
 546  *
 547  *     Independent events and group leaders are initially disabled
 548  *     and get enabled by exec. Group members are ruled by group
 549  *     leaders as stated in 1).
 550  *
 551  *  3) For traced programs attached by perf (pid/tid):
 552  *     - we specifically enable or disable all events during
 553  *       the record command
 554  *
 555  *     When attaching events to already running traced we
 556  *     enable/disable events specifically, as there's no
 557  *     initial traced exec call.
 558  */
 559 void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts)
 560 {
 561         struct perf_evsel *leader = evsel->leader;
 562         struct perf_event_attr *attr = &evsel->attr;
 563         int track = !evsel->idx; /* only the first counter needs these */
 564         bool per_cpu = opts->target.default_per_cpu && !opts->target.per_thread;
 565
 566         attr->sample_id_all = perf_missing_features.sample_id_all ? 0 : 1;
 567         attr->inherit       = !opts->no_inherit;
 568
 569         perf_evsel__set_sample_bit(evsel, IP);
 570         perf_evsel__set_sample_bit(evsel, TID);
 571
 572         if (evsel->sample_read) {
 573                 perf_evsel__set_sample_bit(evsel, READ);
 574
 575                 /*
 576                  * We need ID even in case of single event, because
 577                  * PERF_SAMPLE_READ process ID specific data.
 578                  */
 579                 perf_evsel__set_sample_id(evsel, false);
 580
 581                 /*
 582                  * Apply group format only if we belong to group
 583                  * with more than one members.
 584                  */
 585                 if (leader->nr_members > 1) {
 586                         attr->read_format |= PERF_FORMAT_GROUP;
 587                         attr->inherit = 0;
 588                 }
 589         }
 590
 591         /*
 592          * We default some events to have a default interval. But keep
 593          * it a weak assumption overridable by the user.
 594          */
 595         if (!attr->sample_period || (opts->user_freq != UINT_MAX ||
 596                                      opts->user_interval != ULLONG_MAX)) {
 597                 if (opts->freq) {
 598                         perf_evsel__set_sample_bit(evsel, PERIOD);
 599                         attr->freq              = 1;
 600                         attr->sample_freq       = opts->freq;
 601                 } else {
 602                         attr->sample_period = opts->default_interval;
 603                 }
 604         }
 605
 606         /*
 607          * Disable sampling for all group members other
 608          * than leader in case leader 'leads' the sampling.
 609          */
 610         if ((leader != evsel) && leader->sample_read) {
 611                 attr->sample_freq   = 0;
 612                 attr->sample_period = 0;
 613         }
 614
 615         if (opts->no_samples)
 616                 attr->sample_freq = 0;
 617
 618         if (opts->inherit_stat)
 619                 attr->inherit_stat = 1;
 620
 621         if (opts->sample_address) {
 622                 perf_evsel__set_sample_bit(evsel, ADDR);
 623                 attr->mmap_data = track;
 624         }
 625
 626         if (opts->call_graph_enabled && !evsel->no_aux_samples)
 627                 perf_evsel__config_callgraph(evsel, opts);
 628
 629         if (target__has_cpu(&opts->target))
 630                 perf_evsel__set_sample_bit(evsel, CPU);
 631
 632         if (opts->period)
 633                 perf_evsel__set_sample_bit(evsel, PERIOD);
 634
 635         if (!perf_missing_features.sample_id_all &&
 636             (opts->sample_time || !opts->no_inherit ||
 637              target__has_cpu(&opts->target) || per_cpu))
 638                 perf_evsel__set_sample_bit(evsel, TIME);
 639
 640         if (opts->raw_samples && !evsel->no_aux_samples) {
 641                 perf_evsel__set_sample_bit(evsel, TIME);
 642                 perf_evsel__set_sample_bit(evsel, RAW);
 643                 perf_evsel__set_sample_bit(evsel, CPU);
 644         }
 645
 646         if (opts->sample_address)
 647                 perf_evsel__set_sample_bit(evsel, DATA_SRC);
 648
 649         if (opts->no_buffering) {
 650                 attr->watermark = 0;
 651                 attr->wakeup_events = 1;
 652         }
 653         if (opts->branch_stack && !evsel->no_aux_samples) {
 654                 perf_evsel__set_sample_bit(evsel, BRANCH_STACK);
 655                 attr->branch_sample_type = opts->branch_stack;
 656         }
 657
 658         if (opts->sample_weight)
 659                 perf_evsel__set_sample_bit(evsel, WEIGHT);
 660
 661         attr->mmap  = track;
 662         attr->mmap2 = track && !perf_missing_features.mmap2;
 663         attr->comm  = track;
 664
 665         if (opts->sample_transaction)
 666                 perf_evsel__set_sample_bit(evsel, TRANSACTION);
 667
 668         /*
 669          * XXX see the function comment above
 670          *
 671          * Disabling only independent events or group leaders,
 672          * keeping group members enabled.
 673          */
 674         if (perf_evsel__is_group_leader(evsel))
 675                 attr->disabled = 1;
 676
 677         /*
 678          * Setting enable_on_exec for independent events and
 679          * group leaders for traced executed by perf.
 680          */
 681         if (target__none(&opts->target) && perf_evsel__is_group_leader(evsel) &&
 682                 !opts->initial_delay)
 683                 attr->enable_on_exec = 1;
 684
 685         if (evsel->immediate) {
 686                 attr->disabled = 0;
 687                 attr->enable_on_exec = 0;
 688         }
 689 }
 690
 691 int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
 692 {
 693         int cpu, thread;
 694         evsel->fd = xyarray__new(ncpus, nthreads, sizeof(int));
 695
 696         if (evsel->fd) {
 697                 for (cpu = 0; cpu < ncpus; cpu++) {
 698                         for (thread = 0; thread < nthreads; thread++) {
 699                                 FD(evsel, cpu, thread) = -1;
 700                         }
 701                 }
 702         }
 703
 704         return evsel->fd != NULL ? 0 : -ENOMEM;
 705 }
 706
 707 static int perf_evsel__run_ioctl(struct perf_evsel *evsel, int ncpus, int nthreads,
 708                           int ioc,  void *arg)
 709 {
 710         int cpu, thread;
 711
 712         for (cpu = 0; cpu < ncpus; cpu++) {
 713                 for (thread = 0; thread < nthreads; thread++) {
 714                         int fd = FD(evsel, cpu, thread),
 715                             err = ioctl(fd, ioc, arg);
 716
 717                         if (err)
 718                                 return err;
 719                 }
 720         }
 721
 722         return 0;
 723 }
 724
 725 int perf_evsel__set_filter(struct perf_evsel *evsel, int ncpus, int nthreads,
 726                            const char *filter)
 727 {
 728         return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
 729                                      PERF_EVENT_IOC_SET_FILTER,
 730                                      (void *)filter);
 731 }
 732
 733 int perf_evsel__enable(struct perf_evsel *evsel, int ncpus, int nthreads)
 734 {
 735         return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
 736                                      PERF_EVENT_IOC_ENABLE,
 737                                      0);
 738 }
 739
 740 int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
 741 {
 742         evsel->sample_id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
 743         if (evsel->sample_id == NULL)
 744                 return -ENOMEM;
 745
 746         evsel->id = zalloc(ncpus * nthreads * sizeof(u64));
 747         if (evsel->id == NULL) {
 748                 xyarray__delete(evsel->sample_id);
 749                 evsel->sample_id = NULL;
 750                 return -ENOMEM;
 751         }
 752
 753         return 0;
 754 }
 755
 756 void perf_evsel__reset_counts(struct perf_evsel *evsel, int ncpus)
 757 {
 758         memset(evsel->counts, 0, (sizeof(*evsel->counts) +
 759                                  (ncpus * sizeof(struct perf_counts_values))));
 760 }
 761
 762 int perf_evsel__alloc_counts(struct perf_evsel *evsel, int ncpus)
 763 {
 764         evsel->counts = zalloc((sizeof(*evsel->counts) +
 765                                 (ncpus * sizeof(struct perf_counts_values))));
 766         return evsel->counts != NULL ? 0 : -ENOMEM;
 767 }
 768
 769 void perf_evsel__free_fd(struct perf_evsel *evsel)
 770 {
 771         xyarray__delete(evsel->fd);
 772         evsel->fd = NULL;
 773 }
 774
 775 void perf_evsel__free_id(struct perf_evsel *evsel)
 776 {
 777         xyarray__delete(evsel->sample_id);
 778         evsel->sample_id = NULL;
 779         zfree(&evsel->id);
 780 }
 781
 782 void perf_evsel__close_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
 783 {
 784         int cpu, thread;
 785
 786         for (cpu = 0; cpu < ncpus; cpu++)
 787                 for (thread = 0; thread < nthreads; ++thread) {
 788                         close(FD(evsel, cpu, thread));
 789                         FD(evsel, cpu, thread) = -1;
 790                 }
 791 }
 792
 793 void perf_evsel__free_counts(struct perf_evsel *evsel)
 794 {
 795         zfree(&evsel->counts);
 796 }
 797
 798 void perf_evsel__exit(struct perf_evsel *evsel)
 799 {
 800         assert(list_empty(&evsel->node));
 801         perf_evsel__free_fd(evsel);
 802         perf_evsel__free_id(evsel);
 803 }
 804
 805 void perf_evsel__delete(struct perf_evsel *evsel)
 806 {
 807         perf_evsel__exit(evsel);
 808         close_cgroup(evsel->cgrp);
 809         zfree(&evsel->group_name);
 810         if (evsel->tp_format)
 811                 pevent_free_format(evsel->tp_format);
 812         zfree(&evsel->name);
 813         free(evsel);
 814 }
 815
 816 static inline void compute_deltas(struct perf_evsel *evsel,
 817                                   int cpu,
 818                                   struct perf_counts_values *count)
 819 {
 820         struct perf_counts_values tmp;
 821
 822         if (!evsel->prev_raw_counts)
 823                 return;
 824
 825         if (cpu == -1) {
 826                 tmp = evsel->prev_raw_counts->aggr;
 827                 evsel->prev_raw_counts->aggr = *count;
 828         } else {
 829                 tmp = evsel->prev_raw_counts->cpu[cpu];
 830                 evsel->prev_raw_counts->cpu[cpu] = *count;
 831         }
 832
 833         count->val = count->val - tmp.val;
 834         count->ena = count->ena - tmp.ena;
 835         count->run = count->run - tmp.run;
 836 }
 837
 838 int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
 839                               int cpu, int thread, bool scale)
 840 {
 841         struct perf_counts_values count;
 842         size_t nv = scale ? 3 : 1;
 843
 844         if (FD(evsel, cpu, thread) < 0)
 845                 return -EINVAL;
 846
 847         if (evsel->counts == NULL && perf_evsel__alloc_counts(evsel, cpu + 1) < 0)
 848                 return -ENOMEM;
 849
 850         if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) < 0)
 851                 return -errno;
 852
 853         compute_deltas(evsel, cpu, &count);
 854
 855         if (scale) {
 856                 if (count.run == 0)
 857                         count.val = 0;
 858                 else if (count.run < count.ena)
 859                         count.val = (u64)((double)count.val * count.ena / count.run + 0.5);
 860         } else
 861                 count.ena = count.run = 0;
 862
 863         evsel->counts->cpu[cpu] = count;
 864         return 0;
 865 }
 866
 867 int __perf_evsel__read(struct perf_evsel *evsel,
 868                        int ncpus, int nthreads, bool scale)
 869 {
 870         size_t nv = scale ? 3 : 1;
 871         int cpu, thread;
 872         struct perf_counts_values *aggr = &evsel->counts->aggr, count;
 873
 874         aggr->val = aggr->ena = aggr->run = 0;
 875
 876         for (cpu = 0; cpu < ncpus; cpu++) {
 877                 for (thread = 0; thread < nthreads; thread++) {
 878                         if (FD(evsel, cpu, thread) < 0)
 879                                 continue;
 880
 881                         if (readn(FD(evsel, cpu, thread),
 882                                   &count, nv * sizeof(u64)) < 0)
 883                                 return -errno;
 884
 885                         aggr->val += count.val;
 886                         if (scale) {
 887                                 aggr->ena += count.ena;
 888                                 aggr->run += count.run;
 889                         }
 890                 }
 891         }
 892
 893         compute_deltas(evsel, -1, aggr);
 894
 895         evsel->counts->scaled = 0;
 896         if (scale) {
 897                 if (aggr->run == 0) {
 898                         evsel->counts->scaled = -1;
 899                         aggr->val = 0;
 900                         return 0;
 901                 }
 902
 903                 if (aggr->run < aggr->ena) {
 904                         evsel->counts->scaled = 1;
 905                         aggr->val = (u64)((double)aggr->val * aggr->ena / aggr->run + 0.5);
 906                 }
 907         } else
 908                 aggr->ena = aggr->run = 0;
 909
 910         return 0;
 911 }
 912
 913 static int get_group_fd(struct perf_evsel *evsel, int cpu, int thread)
 914 {
 915         struct perf_evsel *leader = evsel->leader;
 916         int fd;
 917
 918         if (perf_evsel__is_group_leader(evsel))
 919                 return -1;
 920
 921         /*
 922          * Leader must be already processed/open,
 923          * if not it's a bug.
 924          */
 925         BUG_ON(!leader->fd);
 926
 927         fd = FD(leader, cpu, thread);
 928         BUG_ON(fd == -1);
 929
 930         return fd;
 931 }
 932
 933 #define __PRINT_ATTR(fmt, cast, field)  \
 934         fprintf(fp, "  %-19s "fmt"\n", #field, cast attr->field)
 935
 936 #define PRINT_ATTR_U32(field)  __PRINT_ATTR("%u" , , field)
 937 #define PRINT_ATTR_X32(field)  __PRINT_ATTR("%#x", , field)
 938 #define PRINT_ATTR_U64(field)  __PRINT_ATTR("%" PRIu64, (uint64_t), field)
 939 #define PRINT_ATTR_X64(field)  __PRINT_ATTR("%#"PRIx64, (uint64_t), field)
 940
 941 #define PRINT_ATTR2N(name1, field1, name2, field2)      \
 942         fprintf(fp, "  %-19s %u    %-19s %u\n",         \
 943         name1, attr->field1, name2, attr->field2)
 944
 945 #define PRINT_ATTR2(field1, field2) \
 946         PRINT_ATTR2N(#field1, field1, #field2, field2)
 947
 948 static size_t perf_event_attr__fprintf(struct perf_event_attr *attr, FILE *fp)
 949 {
 950         size_t ret = 0;
 951
 952         ret += fprintf(fp, "%.60s\n", graph_dotted_line);
 953         ret += fprintf(fp, "perf_event_attr:\n");
 954
 955         ret += PRINT_ATTR_U32(type);
 956         ret += PRINT_ATTR_U32(size);
 957         ret += PRINT_ATTR_X64(config);
 958         ret += PRINT_ATTR_U64(sample_period);
 959         ret += PRINT_ATTR_U64(sample_freq);
 960         ret += PRINT_ATTR_X64(sample_type);
 961         ret += PRINT_ATTR_X64(read_format);
 962
 963         ret += PRINT_ATTR2(disabled, inherit);
 964         ret += PRINT_ATTR2(pinned, exclusive);
 965         ret += PRINT_ATTR2(exclude_user, exclude_kernel);
 966         ret += PRINT_ATTR2(exclude_hv, exclude_idle);
 967         ret += PRINT_ATTR2(mmap, comm);
 968         ret += PRINT_ATTR2(mmap2, comm_exec);
 969         ret += PRINT_ATTR2(freq, inherit_stat);
 970         ret += PRINT_ATTR2(enable_on_exec, task);
 971         ret += PRINT_ATTR2(watermark, precise_ip);
 972         ret += PRINT_ATTR2(mmap_data, sample_id_all);
 973         ret += PRINT_ATTR2(exclude_host, exclude_guest);
 974         ret += PRINT_ATTR2N("excl.callchain_kern", exclude_callchain_kernel,
 975                             "excl.callchain_user", exclude_callchain_user);
 976
 977         ret += PRINT_ATTR_U32(wakeup_events);
 978         ret += PRINT_ATTR_U32(wakeup_watermark);
 979         ret += PRINT_ATTR_X32(bp_type);
 980         ret += PRINT_ATTR_X64(bp_addr);
 981         ret += PRINT_ATTR_X64(config1);
 982         ret += PRINT_ATTR_U64(bp_len);
 983         ret += PRINT_ATTR_X64(config2);
 984         ret += PRINT_ATTR_X64(branch_sample_type);
 985         ret += PRINT_ATTR_X64(sample_regs_user);
 986         ret += PRINT_ATTR_U32(sample_stack_user);
 987
 988         ret += fprintf(fp, "%.60s\n", graph_dotted_line);
 989
 990         return ret;
 991 }
 992
 993 static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
 994                               struct thread_map *threads)
 995 {
 996         int cpu, thread;
 997         unsigned long flags = 0;
 998         int pid = -1, err;
 999         enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;
1000
1001         if (evsel->fd == NULL &&
1002             perf_evsel__alloc_fd(evsel, cpus->nr, threads->nr) < 0)
1003                 return -ENOMEM;
1004
1005         if (evsel->cgrp) {
1006                 flags = PERF_FLAG_PID_CGROUP;
1007                 pid = evsel->cgrp->fd;
1008         }
1009
1010 fallback_missing_features:
1011         if (perf_missing_features.mmap2)
1012                 evsel->attr.mmap2 = 0;
1013         if (perf_missing_features.exclude_guest)
1014                 evsel->attr.exclude_guest = evsel->attr.exclude_host = 0;
1015 retry_sample_id:
1016         if (perf_missing_features.sample_id_all)
1017                 evsel->attr.sample_id_all = 0;
1018
1019         if (verbose >= 2)
1020                 perf_event_attr__fprintf(&evsel->attr, stderr);
1021
1022         for (cpu = 0; cpu < cpus->nr; cpu++) {
1023
1024                 for (thread = 0; thread < threads->nr; thread++) {
1025                         int group_fd;
1026
1027                         if (!evsel->cgrp)
1028                                 pid = threads->map[thread];
1029
1030                         group_fd = get_group_fd(evsel, cpu, thread);
1031 retry_open:
1032                         pr_debug2("sys_perf_event_open: pid %d  cpu %d  group_fd %d  flags %#lx\n",
1033                                   pid, cpus->map[cpu], group_fd, flags);
1034
1035                         FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr,
1036                                                                      pid,
1037                                                                      cpus->map[cpu],
1038                                                                      group_fd, flags);
1039                         if (FD(evsel, cpu, thread) < 0) {
1040                                 err = -errno;
1041                                 pr_debug2("sys_perf_event_open failed, error %d\n",
1042                                           err);
1043                                 goto try_fallback;
1044                         }
1045                         set_rlimit = NO_CHANGE;
1046                 }
1047         }
1048
1049         return 0;
1050
1051 try_fallback:
1052         /*
1053          * perf stat needs between 5 and 22 fds per CPU. When we run out
1054          * of them try to increase the limits.
1055          */
1056         if (err == -EMFILE && set_rlimit < INCREASED_MAX) {
1057                 struct rlimit l;
1058                 int old_errno = errno;
1059
1060                 if (getrlimit(RLIMIT_NOFILE, &l) == 0) {
1061                         if (set_rlimit == NO_CHANGE)
1062                                 l.rlim_cur = l.rlim_max;
1063                         else {
1064                                 l.rlim_cur = l.rlim_max + 1000;
1065                                 l.rlim_max = l.rlim_cur;
1066                         }
1067                         if (setrlimit(RLIMIT_NOFILE, &l) == 0) {
1068                                 set_rlimit++;
1069                                 errno = old_errno;
1070                                 goto retry_open;
1071                         }
1072                 }
1073                 errno = old_errno;
1074         }
1075
1076         if (err != -EINVAL || cpu > 0 || thread > 0)
1077                 goto out_close;
1078
1079         if (!perf_missing_features.mmap2 && evsel->attr.mmap2) {
1080                 perf_missing_features.mmap2 = true;
1081                 goto fallback_missing_features;
1082         } else if (!perf_missing_features.exclude_guest &&
1083                    (evsel->attr.exclude_guest || evsel->attr.exclude_host)) {
1084                 perf_missing_features.exclude_guest = true;
1085                 goto fallback_missing_features;
1086         } else if (!perf_missing_features.sample_id_all) {
1087                 perf_missing_features.sample_id_all = true;
1088                 goto retry_sample_id;
1089         }
1090
1091 out_close:
1092         do {
1093                 while (--thread >= 0) {
1094                         close(FD(evsel, cpu, thread));
1095                         FD(evsel, cpu, thread) = -1;
1096                 }
1097                 thread = threads->nr;
1098         } while (--cpu >= 0);
1099         return err;
1100 }
1101
1102 void perf_evsel__close(struct perf_evsel *evsel, int ncpus, int nthreads)
1103 {
1104         if (evsel->fd == NULL)
1105                 return;
1106
1107         perf_evsel__close_fd(evsel, ncpus, nthreads);
1108         perf_evsel__free_fd(evsel);
1109 }
1110
1111 static struct {
1112         struct cpu_map map;
1113         int cpus[1];
1114 } empty_cpu_map = {
1115         .map.nr = 1,
1116         .cpus   = { -1, },
1117 };
1118
1119 static struct {
1120         struct thread_map map;
1121         int threads[1];
1122 } empty_thread_map = {
1123         .map.nr  = 1,
1124         .threads = { -1, },
1125 };
1126
1127 int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1128                      struct thread_map *threads)
1129 {
1130         if (cpus == NULL) {
1131                 /* Work around old compiler warnings about strict aliasing */
1132                 cpus = &empty_cpu_map.map;
1133         }
1134
1135         if (threads == NULL)
1136                 threads = &empty_thread_map.map;
1137
1138         return __perf_evsel__open(evsel, cpus, threads);
1139 }
1140
1141 int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
1142                              struct cpu_map *cpus)
1143 {
1144         return __perf_evsel__open(evsel, cpus, &empty_thread_map.map);
1145 }
1146
1147 int perf_evsel__open_per_thread(struct perf_evsel *evsel,
1148                                 struct thread_map *threads)
1149 {
1150         return __perf_evsel__open(evsel, &empty_cpu_map.map, threads);
1151 }
1152
1153 static int perf_evsel__parse_id_sample(const struct perf_evsel *evsel,
1154                                        const union perf_event *event,
1155                                        struct perf_sample *sample)
1156 {
1157         u64 type = evsel->attr.sample_type;
1158         const u64 *array = event->sample.array;
1159         bool swapped = evsel->needs_swap;
1160         union u64_swap u;
1161
1162         array += ((event->header.size -
1163                    sizeof(event->header)) / sizeof(u64)) - 1;
1164
1165         if (type & PERF_SAMPLE_IDENTIFIER) {
1166                 sample->id = *array;
1167                 array--;
1168         }
1169
1170         if (type & PERF_SAMPLE_CPU) {
1171                 u.val64 = *array;
1172                 if (swapped) {
1173                         /* undo swap of u64, then swap on individual u32s */
1174                         u.val64 = bswap_64(u.val64);
1175                         u.val32[0] = bswap_32(u.val32[0]);
1176                 }
1177
1178                 sample->cpu = u.val32[0];
1179                 array--;
1180         }
1181
1182         if (type & PERF_SAMPLE_STREAM_ID) {
1183                 sample->stream_id = *array;
1184                 array--;
1185         }
1186
1187         if (type & PERF_SAMPLE_ID) {
1188                 sample->id = *array;
1189                 array--;
1190         }
1191
1192         if (type & PERF_SAMPLE_TIME) {
1193                 sample->time = *array;
1194                 array--;
1195         }
1196
1197         if (type & PERF_SAMPLE_TID) {
1198                 u.val64 = *array;
1199                 if (swapped) {
1200                         /* undo swap of u64, then swap on individual u32s */
1201                         u.val64 = bswap_64(u.val64);
1202                         u.val32[0] = bswap_32(u.val32[0]);
1203                         u.val32[1] = bswap_32(u.val32[1]);
1204                 }
1205
1206                 sample->pid = u.val32[0];
1207                 sample->tid = u.val32[1];
1208                 array--;
1209         }
1210
1211         return 0;
1212 }
1213
1214 static inline bool overflow(const void *endp, u16 max_size, const void *offset,
1215                             u64 size)
1216 {
1217         return size > max_size || offset + size > endp;
1218 }
1219
1220 #define OVERFLOW_CHECK(offset, size, max_size)                          \
1221         do {                                                            \
1222                 if (overflow(endp, (max_size), (offset), (size)))       \
1223                         return -EFAULT;                                 \
1224         } while (0)
1225
1226 #define OVERFLOW_CHECK_u64(offset) \
1227         OVERFLOW_CHECK(offset, sizeof(u64), sizeof(u64))
1228
1229 int perf_evsel__parse_sample(struct perf_evsel *evsel, union perf_event *event,
1230                              struct perf_sample *data)
1231 {
1232         u64 type = evsel->attr.sample_type;
1233         bool swapped = evsel->needs_swap;
1234         const u64 *array;
1235         u16 max_size = event->header.size;
1236         const void *endp = (void *)event + max_size;
1237         u64 sz;
1238
1239         /*
1240          * used for cross-endian analysis. See git commit 65014ab3
1241          * for why this goofiness is needed.
1242          */
1243         union u64_swap u;
1244
1245         memset(data, 0, sizeof(*data));
1246         data->cpu = data->pid = data->tid = -1;
1247         data->stream_id = data->id = data->time = -1ULL;
1248         data->period = evsel->attr.sample_period;
1249         data->weight = 0;
1250
1251         if (event->header.type != PERF_RECORD_SAMPLE) {
1252                 if (!evsel->attr.sample_id_all)
1253                         return 0;
1254                 return perf_evsel__parse_id_sample(evsel, event, data);
1255         }
1256
1257         array = event->sample.array;
1258
1259         /*
1260          * The evsel's sample_size is based on PERF_SAMPLE_MASK which includes
1261          * up to PERF_SAMPLE_PERIOD.  After that overflow() must be used to
1262          * check the format does not go past the end of the event.
1263          */
1264         if (evsel->sample_size + sizeof(event->header) > event->header.size)
1265                 return -EFAULT;
1266
1267         data->id = -1ULL;
1268         if (type & PERF_SAMPLE_IDENTIFIER) {
1269                 data->id = *array;
1270                 array++;
1271         }
1272
1273         if (type & PERF_SAMPLE_IP) {
1274                 data->ip = *array;
1275                 array++;
1276         }
1277
1278         if (type & PERF_SAMPLE_TID) {
1279                 u.val64 = *array;
1280                 if (swapped) {
1281                         /* undo swap of u64, then swap on individual u32s */
1282                         u.val64 = bswap_64(u.val64);
1283                         u.val32[0] = bswap_32(u.val32[0]);
1284                         u.val32[1] = bswap_32(u.val32[1]);
1285                 }
1286
1287                 data->pid = u.val32[0];
1288                 data->tid = u.val32[1];
1289                 array++;
1290         }
1291
1292         if (type & PERF_SAMPLE_TIME) {
1293                 data->time = *array;
1294                 array++;
1295         }
1296
1297         data->addr = 0;
1298         if (type & PERF_SAMPLE_ADDR) {
1299                 data->addr = *array;
1300                 array++;
1301         }
1302
1303         if (type & PERF_SAMPLE_ID) {
1304                 data->id = *array;
1305                 array++;
1306         }
1307
1308         if (type & PERF_SAMPLE_STREAM_ID) {
1309                 data->stream_id = *array;
1310                 array++;
1311         }
1312
1313         if (type & PERF_SAMPLE_CPU) {
1314
1315                 u.val64 = *array;
1316                 if (swapped) {
1317                         /* undo swap of u64, then swap on individual u32s */
1318                         u.val64 = bswap_64(u.val64);
1319                         u.val32[0] = bswap_32(u.val32[0]);
1320                 }
1321
1322                 data->cpu = u.val32[0];
1323                 array++;
1324         }
1325
1326         if (type & PERF_SAMPLE_PERIOD) {
1327                 data->period = *array;
1328                 array++;
1329         }
1330
1331         if (type & PERF_SAMPLE_READ) {
1332                 u64 read_format = evsel->attr.read_format;
1333
1334                 OVERFLOW_CHECK_u64(array);
1335                 if (read_format & PERF_FORMAT_GROUP)
1336                         data->read.group.nr = *array;
1337                 else
1338                         data->read.one.value = *array;
1339
1340                 array++;
1341
1342                 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1343                         OVERFLOW_CHECK_u64(array);
1344                         data->read.time_enabled = *array;
1345                         array++;
1346                 }
1347
1348                 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1349                         OVERFLOW_CHECK_u64(array);
1350                         data->read.time_running = *array;
1351                         array++;
1352                 }
1353
1354                 /* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1355                 if (read_format & PERF_FORMAT_GROUP) {
1356                         const u64 max_group_nr = UINT64_MAX /
1357                                         sizeof(struct sample_read_value);
1358
1359                         if (data->read.group.nr > max_group_nr)
1360                                 return -EFAULT;
1361                         sz = data->read.group.nr *
1362                              sizeof(struct sample_read_value);
1363                         OVERFLOW_CHECK(array, sz, max_size);
1364                         data->read.group.values =
1365                                         (struct sample_read_value *)array;
1366                         array = (void *)array + sz;
1367                 } else {
1368                         OVERFLOW_CHECK_u64(array);
1369                         data->read.one.id = *array;
1370                         array++;
1371                 }
1372         }
1373
1374         if (type & PERF_SAMPLE_CALLCHAIN) {
1375                 const u64 max_callchain_nr = UINT64_MAX / sizeof(u64);
1376
1377                 OVERFLOW_CHECK_u64(array);
1378                 data->callchain = (struct ip_callchain *)array++;
1379                 if (data->callchain->nr > max_callchain_nr)
1380                         return -EFAULT;
1381                 sz = data->callchain->nr * sizeof(u64);
1382                 OVERFLOW_CHECK(array, sz, max_size);
1383                 array = (void *)array + sz;
1384         }
1385
1386         if (type & PERF_SAMPLE_RAW) {
1387                 OVERFLOW_CHECK_u64(array);
1388                 u.val64 = *array;
1389                 if (WARN_ONCE(swapped,
1390                               "Endianness of raw data not corrected!\n")) {
1391                         /* undo swap of u64, then swap on individual u32s */
1392                         u.val64 = bswap_64(u.val64);
1393                         u.val32[0] = bswap_32(u.val32[0]);
1394                         u.val32[1] = bswap_32(u.val32[1]);
1395                 }
1396                 data->raw_size = u.val32[0];
1397                 array = (void *)array + sizeof(u32);
1398
1399                 OVERFLOW_CHECK(array, data->raw_size, max_size);
1400                 data->raw_data = (void *)array;
1401                 array = (void *)array + data->raw_size;
1402         }
1403
1404         if (type & PERF_SAMPLE_BRANCH_STACK) {
1405                 const u64 max_branch_nr = UINT64_MAX /
1406                                           sizeof(struct branch_entry);
1407
1408                 OVERFLOW_CHECK_u64(array);
1409                 data->branch_stack = (struct branch_stack *)array++;
1410
1411                 if (data->branch_stack->nr > max_branch_nr)
1412                         return -EFAULT;
1413                 sz = data->branch_stack->nr * sizeof(struct branch_entry);
1414                 OVERFLOW_CHECK(array, sz, max_size);
1415                 array = (void *)array + sz;
1416         }
1417
1418         if (type & PERF_SAMPLE_REGS_USER) {
1419                 OVERFLOW_CHECK_u64(array);
1420                 data->user_regs.abi = *array;
1421                 array++;
1422
1423                 if (data->user_regs.abi) {
1424                         u64 mask = evsel->attr.sample_regs_user;
1425
1426                         sz = hweight_long(mask) * sizeof(u64);
1427                         OVERFLOW_CHECK(array, sz, max_size);
1428                         data->user_regs.mask = mask;
1429                         data->user_regs.regs = (u64 *)array;
1430                         array = (void *)array + sz;
1431                 }
1432         }
1433
1434         if (type & PERF_SAMPLE_STACK_USER) {
1435                 OVERFLOW_CHECK_u64(array);
1436                 sz = *array++;
1437
1438                 data->user_stack.offset = ((char *)(array - 1)
1439                                           - (char *) event);
1440
1441                 if (!sz) {
1442                         data->user_stack.size = 0;
1443                 } else {
1444                         OVERFLOW_CHECK(array, sz, max_size);
1445                         data->user_stack.data = (char *)array;
1446                         array = (void *)array + sz;
1447                         OVERFLOW_CHECK_u64(array);
1448                         data->user_stack.size = *array++;
1449                         if (WARN_ONCE(data->user_stack.size > sz,
1450                                       "user stack dump failure\n"))
1451                                 return -EFAULT;
1452                 }
1453         }
1454
1455         data->weight = 0;
1456         if (type & PERF_SAMPLE_WEIGHT) {
1457                 OVERFLOW_CHECK_u64(array);
1458                 data->weight = *array;
1459                 array++;
1460         }
1461
1462         data->data_src = PERF_MEM_DATA_SRC_NONE;
1463         if (type & PERF_SAMPLE_DATA_SRC) {
1464                 OVERFLOW_CHECK_u64(array);
1465                 data->data_src = *array;
1466                 array++;
1467         }
1468
1469         data->transaction = 0;
1470         if (type & PERF_SAMPLE_TRANSACTION) {
1471                 OVERFLOW_CHECK_u64(array);
1472                 data->transaction = *array;
1473                 array++;
1474         }
1475
1476         return 0;
1477 }
1478
1479 size_t perf_event__sample_event_size(const struct perf_sample *sample, u64 type,
1480                                      u64 read_format)
1481 {
1482         size_t sz, result = sizeof(struct sample_event);
1483
1484         if (type & PERF_SAMPLE_IDENTIFIER)
1485                 result += sizeof(u64);
1486
1487         if (type & PERF_SAMPLE_IP)
1488                 result += sizeof(u64);
1489
1490         if (type & PERF_SAMPLE_TID)
1491                 result += sizeof(u64);
1492
1493         if (type & PERF_SAMPLE_TIME)
1494                 result += sizeof(u64);
1495
1496         if (type & PERF_SAMPLE_ADDR)
1497                 result += sizeof(u64);
1498
1499         if (type & PERF_SAMPLE_ID)
1500                 result += sizeof(u64);
1501
1502         if (type & PERF_SAMPLE_STREAM_ID)
1503                 result += sizeof(u64);
1504
1505         if (type & PERF_SAMPLE_CPU)
1506                 result += sizeof(u64);
1507
1508         if (type & PERF_SAMPLE_PERIOD)
1509                 result += sizeof(u64);
1510
1511         if (type & PERF_SAMPLE_READ) {
1512                 result += sizeof(u64);
1513                 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
1514                         result += sizeof(u64);
1515                 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
1516                         result += sizeof(u64);
1517                 /* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1518                 if (read_format & PERF_FORMAT_GROUP) {
1519                         sz = sample->read.group.nr *
1520                              sizeof(struct sample_read_value);
1521                         result += sz;
1522                 } else {
1523                         result += sizeof(u64);
1524                 }
1525         }
1526
1527         if (type & PERF_SAMPLE_CALLCHAIN) {
1528                 sz = (sample->callchain->nr + 1) * sizeof(u64);
1529                 result += sz;
1530         }
1531
1532         if (type & PERF_SAMPLE_RAW) {
1533                 result += sizeof(u32);
1534                 result += sample->raw_size;
1535         }
1536
1537         if (type & PERF_SAMPLE_BRANCH_STACK) {
1538                 sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1539                 sz += sizeof(u64);
1540                 result += sz;
1541         }
1542
1543         if (type & PERF_SAMPLE_REGS_USER) {
1544                 if (sample->user_regs.abi) {
1545                         result += sizeof(u64);
1546                         sz = hweight_long(sample->user_regs.mask) * sizeof(u64);
1547                         result += sz;
1548                 } else {
1549                         result += sizeof(u64);
1550                 }
1551         }
1552
1553         if (type & PERF_SAMPLE_STACK_USER) {
1554                 sz = sample->user_stack.size;
1555                 result += sizeof(u64);
1556                 if (sz) {
1557                         result += sz;
1558                         result += sizeof(u64);
1559                 }
1560         }
1561
1562         if (type & PERF_SAMPLE_WEIGHT)
1563                 result += sizeof(u64);
1564
1565         if (type & PERF_SAMPLE_DATA_SRC)
1566                 result += sizeof(u64);
1567
1568         if (type & PERF_SAMPLE_TRANSACTION)
1569                 result += sizeof(u64);
1570
1571         return result;
1572 }
1573
1574 int perf_event__synthesize_sample(union perf_event *event, u64 type,
1575                                   u64 read_format,
1576                                   const struct perf_sample *sample,
1577                                   bool swapped)
1578 {
1579         u64 *array;
1580         size_t sz;
1581         /*
1582          * used for cross-endian analysis. See git commit 65014ab3
1583          * for why this goofiness is needed.
1584          */
1585         union u64_swap u;
1586
1587         array = event->sample.array;
1588
1589         if (type & PERF_SAMPLE_IDENTIFIER) {
1590                 *array = sample->id;
1591                 array++;
1592         }
1593
1594         if (type & PERF_SAMPLE_IP) {
1595                 *array = sample->ip;
1596                 array++;
1597         }
1598
1599         if (type & PERF_SAMPLE_TID) {
1600                 u.val32[0] = sample->pid;
1601                 u.val32[1] = sample->tid;
1602                 if (swapped) {
1603                         /*
1604                          * Inverse of what is done in perf_evsel__parse_sample
1605                          */
1606                         u.val32[0] = bswap_32(u.val32[0]);
1607                         u.val32[1] = bswap_32(u.val32[1]);
1608                         u.val64 = bswap_64(u.val64);
1609                 }
1610
1611                 *array = u.val64;
1612                 array++;
1613         }
1614
1615         if (type & PERF_SAMPLE_TIME) {
1616                 *array = sample->time;
1617                 array++;
1618         }
1619
1620         if (type & PERF_SAMPLE_ADDR) {
1621                 *array = sample->addr;
1622                 array++;
1623         }
1624
1625         if (type & PERF_SAMPLE_ID) {
1626                 *array = sample->id;
1627                 array++;
1628         }
1629
1630         if (type & PERF_SAMPLE_STREAM_ID) {
1631                 *array = sample->stream_id;
1632                 array++;
1633         }
1634
1635         if (type & PERF_SAMPLE_CPU) {
1636                 u.val32[0] = sample->cpu;
1637                 if (swapped) {
1638                         /*
1639                          * Inverse of what is done in perf_evsel__parse_sample
1640                          */
1641                         u.val32[0] = bswap_32(u.val32[0]);
1642                         u.val64 = bswap_64(u.val64);
1643                 }
1644                 *array = u.val64;
1645                 array++;
1646         }
1647
1648         if (type & PERF_SAMPLE_PERIOD) {
1649                 *array = sample->period;
1650                 array++;
1651         }
1652
1653         if (type & PERF_SAMPLE_READ) {
1654                 if (read_format & PERF_FORMAT_GROUP)
1655                         *array = sample->read.group.nr;
1656                 else
1657                         *array = sample->read.one.value;
1658                 array++;
1659
1660                 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1661                         *array = sample->read.time_enabled;
1662                         array++;
1663                 }
1664
1665                 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1666                         *array = sample->read.time_running;
1667                         array++;
1668                 }
1669
1670                 /* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1671                 if (read_format & PERF_FORMAT_GROUP) {
1672                         sz = sample->read.group.nr *
1673                              sizeof(struct sample_read_value);
1674                         memcpy(array, sample->read.group.values, sz);
1675                         array = (void *)array + sz;
1676                 } else {
1677                         *array = sample->read.one.id;
1678                         array++;
1679                 }
1680         }
1681
1682         if (type & PERF_SAMPLE_CALLCHAIN) {
1683                 sz = (sample->callchain->nr + 1) * sizeof(u64);
1684                 memcpy(array, sample->callchain, sz);
1685                 array = (void *)array + sz;
1686         }
1687
1688         if (type & PERF_SAMPLE_RAW) {
1689                 u.val32[0] = sample->raw_size;
1690                 if (WARN_ONCE(swapped,
1691                               "Endianness of raw data not corrected!\n")) {
1692                         /*
1693                          * Inverse of what is done in perf_evsel__parse_sample
1694                          */
1695                         u.val32[0] = bswap_32(u.val32[0]);
1696                         u.val32[1] = bswap_32(u.val32[1]);
1697                         u.val64 = bswap_64(u.val64);
1698                 }
1699                 *array = u.val64;
1700                 array = (void *)array + sizeof(u32);
1701
1702                 memcpy(array, sample->raw_data, sample->raw_size);
1703                 array = (void *)array + sample->raw_size;
1704         }
1705
1706         if (type & PERF_SAMPLE_BRANCH_STACK) {
1707                 sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1708                 sz += sizeof(u64);
1709                 memcpy(array, sample->branch_stack, sz);
1710                 array = (void *)array + sz;
1711         }
1712
1713         if (type & PERF_SAMPLE_REGS_USER) {
1714                 if (sample->user_regs.abi) {
1715                         *array++ = sample->user_regs.abi;
1716                         sz = hweight_long(sample->user_regs.mask) * sizeof(u64);
1717                         memcpy(array, sample->user_regs.regs, sz);
1718                         array = (void *)array + sz;
1719                 } else {
1720                         *array++ = 0;
1721                 }
1722         }
1723
1724         if (type & PERF_SAMPLE_STACK_USER) {
1725                 sz = sample->user_stack.size;
1726                 *array++ = sz;
1727                 if (sz) {
1728                         memcpy(array, sample->user_stack.data, sz);
1729                         array = (void *)array + sz;
1730                         *array++ = sz;
1731                 }
1732         }
1733
1734         if (type & PERF_SAMPLE_WEIGHT) {
1735                 *array = sample->weight;
1736                 array++;
1737         }
1738
1739         if (type & PERF_SAMPLE_DATA_SRC) {
1740                 *array = sample->data_src;
1741                 array++;
1742         }
1743
1744         if (type & PERF_SAMPLE_TRANSACTION) {
1745                 *array = sample->transaction;
1746                 array++;
1747         }
1748
1749         return 0;
1750 }
1751
1752 struct format_field *perf_evsel__field(struct perf_evsel *evsel, const char *name)
1753 {
1754         return pevent_find_field(evsel->tp_format, name);
1755 }
1756
1757 void *perf_evsel__rawptr(struct perf_evsel *evsel, struct perf_sample *sample,
1758                          const char *name)
1759 {
1760         struct format_field *field = perf_evsel__field(evsel, name);
1761         int offset;
1762
1763         if (!field)
1764                 return NULL;
1765
1766         offset = field->offset;
1767
1768         if (field->flags & FIELD_IS_DYNAMIC) {
1769                 offset = *(int *)(sample->raw_data + field->offset);
1770                 offset &= 0xffff;
1771         }
1772
1773         return sample->raw_data + offset;
1774 }
1775
1776 u64 perf_evsel__intval(struct perf_evsel *evsel, struct perf_sample *sample,
1777                        const char *name)
1778 {
1779         struct format_field *field = perf_evsel__field(evsel, name);
1780         void *ptr;
1781         u64 value;
1782
1783         if (!field)
1784                 return 0;
1785
1786         ptr = sample->raw_data + field->offset;
1787
1788         switch (field->size) {
1789         case 1:
1790                 return *(u8 *)ptr;
1791         case 2:
1792                 value = *(u16 *)ptr;
1793                 break;
1794         case 4:
1795                 value = *(u32 *)ptr;
1796                 break;
1797         case 8:
1798                 value = *(u64 *)ptr;
1799                 break;
1800         default:
1801                 return 0;
1802         }
1803
1804         if (!evsel->needs_swap)
1805                 return value;
1806
1807         switch (field->size) {
1808         case 2:
1809                 return bswap_16(value);
1810         case 4:
1811                 return bswap_32(value);
1812         case 8:
1813                 return bswap_64(value);
1814         default:
1815                 return 0;
1816         }
1817
1818         return 0;
1819 }
1820
1821 static int comma_fprintf(FILE *fp, bool *first, const char *fmt, ...)
1822 {
1823         va_list args;
1824         int ret = 0;
1825
1826         if (!*first) {
1827                 ret += fprintf(fp, ",");
1828         } else {
1829                 ret += fprintf(fp, ":");
1830                 *first = false;
1831         }
1832
1833         va_start(args, fmt);
1834         ret += vfprintf(fp, fmt, args);
1835         va_end(args);
1836         return ret;
1837 }
1838
1839 static int __if_fprintf(FILE *fp, bool *first, const char *field, u64 value)
1840 {
1841         if (value == 0)
1842                 return 0;
1843
1844         return comma_fprintf(fp, first, " %s: %" PRIu64, field, value);
1845 }
1846
1847 #define if_print(field) printed += __if_fprintf(fp, &first, #field, evsel->attr.field)
1848
1849 struct bit_names {
1850         int bit;
1851         const char *name;
1852 };
1853
1854 static int bits__fprintf(FILE *fp, const char *field, u64 value,
1855                          struct bit_names *bits, bool *first)
1856 {
1857         int i = 0, printed = comma_fprintf(fp, first, " %s: ", field);
1858         bool first_bit = true;
1859
1860         do {
1861                 if (value & bits[i].bit) {
1862                         printed += fprintf(fp, "%s%s", first_bit ? "" : "|", bits[i].name);
1863                         first_bit = false;
1864                 }
1865         } while (bits[++i].name != NULL);
1866
1867         return printed;
1868 }
1869
1870 static int sample_type__fprintf(FILE *fp, bool *first, u64 value)
1871 {
1872 #define bit_name(n) { PERF_SAMPLE_##n, #n }
1873         struct bit_names bits[] = {
1874                 bit_name(IP), bit_name(TID), bit_name(TIME), bit_name(ADDR),
1875                 bit_name(READ), bit_name(CALLCHAIN), bit_name(ID), bit_name(CPU),
1876                 bit_name(PERIOD), bit_name(STREAM_ID), bit_name(RAW),
1877                 bit_name(BRANCH_STACK), bit_name(REGS_USER), bit_name(STACK_USER),
1878                 bit_name(IDENTIFIER),
1879                 { .name = NULL, }
1880         };
1881 #undef bit_name
1882         return bits__fprintf(fp, "sample_type", value, bits, first);
1883 }
1884
1885 static int read_format__fprintf(FILE *fp, bool *first, u64 value)
1886 {
1887 #define bit_name(n) { PERF_FORMAT_##n, #n }
1888         struct bit_names bits[] = {
1889                 bit_name(TOTAL_TIME_ENABLED), bit_name(TOTAL_TIME_RUNNING),
1890                 bit_name(ID), bit_name(GROUP),
1891                 { .name = NULL, }
1892         };
1893 #undef bit_name
1894         return bits__fprintf(fp, "read_format", value, bits, first);
1895 }
1896
1897 int perf_evsel__fprintf(struct perf_evsel *evsel,
1898                         struct perf_attr_details *details, FILE *fp)
1899 {
1900         bool first = true;
1901         int printed = 0;
1902
1903         if (details->event_group) {
1904                 struct perf_evsel *pos;
1905
1906                 if (!perf_evsel__is_group_leader(evsel))
1907                         return 0;
1908
1909                 if (evsel->nr_members > 1)
1910                         printed += fprintf(fp, "%s{", evsel->group_name ?: "");
1911
1912                 printed += fprintf(fp, "%s", perf_evsel__name(evsel));
1913                 for_each_group_member(pos, evsel)
1914                         printed += fprintf(fp, ",%s", perf_evsel__name(pos));
1915
1916                 if (evsel->nr_members > 1)
1917                         printed += fprintf(fp, "}");
1918                 goto out;
1919         }
1920
1921         printed += fprintf(fp, "%s", perf_evsel__name(evsel));
1922
1923         if (details->verbose || details->freq) {
1924                 printed += comma_fprintf(fp, &first, " sample_freq=%" PRIu64,
1925                                          (u64)evsel->attr.sample_freq);
1926         }
1927
1928         if (details->verbose) {
1929                 if_print(type);
1930                 if_print(config);
1931                 if_print(config1);
1932                 if_print(config2);
1933                 if_print(size);
1934                 printed += sample_type__fprintf(fp, &first, evsel->attr.sample_type);
1935                 if (evsel->attr.read_format)
1936                         printed += read_format__fprintf(fp, &first, evsel->attr.read_format);
1937                 if_print(disabled);
1938                 if_print(inherit);
1939                 if_print(pinned);
1940                 if_print(exclusive);
1941                 if_print(exclude_user);
1942                 if_print(exclude_kernel);
1943                 if_print(exclude_hv);
1944                 if_print(exclude_idle);
1945                 if_print(mmap);
1946                 if_print(mmap2);
1947                 if_print(comm);
1948                 if_print(comm_exec);
1949                 if_print(freq);
1950                 if_print(inherit_stat);
1951                 if_print(enable_on_exec);
1952                 if_print(task);
1953                 if_print(watermark);
1954                 if_print(precise_ip);
1955                 if_print(mmap_data);
1956                 if_print(sample_id_all);
1957                 if_print(exclude_host);
1958                 if_print(exclude_guest);
1959                 if_print(__reserved_1);
1960                 if_print(wakeup_events);
1961                 if_print(bp_type);
1962                 if_print(branch_sample_type);
1963         }
1964 out:
1965         fputc('\n', fp);
1966         return ++printed;
1967 }
1968
1969 bool perf_evsel__fallback(struct perf_evsel *evsel, int err,
1970                           char *msg, size_t msgsize)
1971 {
1972         if ((err == ENOENT || err == ENXIO || err == ENODEV) &&
1973             evsel->attr.type   == PERF_TYPE_HARDWARE &&
1974             evsel->attr.config == PERF_COUNT_HW_CPU_CYCLES) {
1975                 /*
1976                  * If it's cycles then fall back to hrtimer based
1977                  * cpu-clock-tick sw counter, which is always available even if
1978                  * no PMU support.
1979                  *
1980                  * PPC returns ENXIO until 2.6.37 (behavior changed with commit
1981                  * b0a873e).
1982                  */
1983                 scnprintf(msg, msgsize, "%s",
1984 "The cycles event is not supported, trying to fall back to cpu-clock-ticks");
1985
1986                 evsel->attr.type   = PERF_TYPE_SOFTWARE;
1987                 evsel->attr.config = PERF_COUNT_SW_CPU_CLOCK;
1988
1989                 zfree(&evsel->name);
1990                 return true;
1991         }
1992
1993         return false;
1994 }
1995
1996 int perf_evsel__open_strerror(struct perf_evsel *evsel, struct target *target,
1997                               int err, char *msg, size_t size)
1998 {
1999         switch (err) {
2000         case EPERM:
2001         case EACCES:
2002                 return scnprintf(msg, size,
2003                  "You may not have permission to collect %sstats.\n"
2004                  "Consider tweaking /proc/sys/kernel/perf_event_paranoid:\n"
2005                  " -1 - Not paranoid at all\n"
2006                  "  0 - Disallow raw tracepoint access for unpriv\n"
2007                  "  1 - Disallow cpu events for unpriv\n"
2008                  "  2 - Disallow kernel profiling for unpriv",
2009                                  target->system_wide ? "system-wide " : "");
2010         case ENOENT:
2011                 return scnprintf(msg, size, "The %s event is not supported.",
2012                                  perf_evsel__name(evsel));
2013         case EMFILE:
2014                 return scnprintf(msg, size, "%s",
2015                          "Too many events are opened.\n"
2016                          "Try again after reducing the number of events.");
2017         case ENODEV:
2018                 if (target->cpu_list)
2019                         return scnprintf(msg, size, "%s",
2020          "No such device - did you specify an out-of-range profile CPU?\n");
2021                 break;
2022         case EOPNOTSUPP:
2023                 if (evsel->attr.precise_ip)
2024                         return scnprintf(msg, size, "%s",
2025         "\'precise\' request may not be supported. Try removing 'p' modifier.");
2026 #if defined(__i386__) || defined(__x86_64__)
2027                 if (evsel->attr.type == PERF_TYPE_HARDWARE)
2028                         return scnprintf(msg, size, "%s",
2029         "No hardware sampling interrupt available.\n"
2030         "No APIC? If so then you can boot the kernel with the \"lapic\" boot parameter to force-enable it.");
2031 #endif
2032                 break;
2033         default:
2034                 break;
2035         }
2036
2037         return scnprintf(msg, size,
2038         "The sys_perf_event_open() syscall returned with %d (%s) for event (%s).  \n"
2039         "/bin/dmesg may provide additional information.\n"
2040         "No CONFIG_PERF_EVENTS=y kernel support configured?\n",
2041                          err, strerror(err), perf_evsel__name(evsel));
2042 }