tools/perf/util/session.c

   1 #include <linux/kernel.h>
   2
   3 #include <byteswap.h>
   4 #include <unistd.h>
   5 #include <sys/types.h>
   6
   7 #include "session.h"
   8 #include "sort.h"
   9 #include "util.h"
  10
  11 static int perf_session__open(struct perf_session *self, bool force)
  12 {
  13         struct stat input_stat;
  14
  15         self->fd = open(self->filename, O_RDONLY);
  16         if (self->fd < 0) {
  17                 pr_err("failed to open file: %s", self->filename);
  18                 if (!strcmp(self->filename, "perf.data"))
  19                         pr_err("  (try 'perf record' first)");
  20                 pr_err("\n");
  21                 return -errno;
  22         }
  23
  24         if (fstat(self->fd, &input_stat) < 0)
  25                 goto out_close;
  26
  27         if (!force && input_stat.st_uid && (input_stat.st_uid != geteuid())) {
  28                 pr_err("file %s not owned by current user or root\n",
  29                        self->filename);
  30                 goto out_close;
  31         }
  32
  33         if (!input_stat.st_size) {
  34                 pr_info("zero-sized file (%s), nothing to do!\n",
  35                         self->filename);
  36                 goto out_close;
  37         }
  38
  39         if (perf_header__read(&self->header, self->fd) < 0) {
  40                 pr_err("incompatible file format");
  41                 goto out_close;
  42         }
  43
  44         self->size = input_stat.st_size;
  45         return 0;
  46
  47 out_close:
  48         close(self->fd);
  49         self->fd = -1;
  50         return -1;
  51 }
  52
  53 struct perf_session *perf_session__new(const char *filename, int mode, bool force)
  54 {
  55         size_t len = filename ? strlen(filename) + 1 : 0;
  56         struct perf_session *self = zalloc(sizeof(*self) + len);
  57
  58         if (self == NULL)
  59                 goto out;
  60
  61         if (perf_header__init(&self->header) < 0)
  62                 goto out_free;
  63
  64         memcpy(self->filename, filename, len);
  65         self->threads = RB_ROOT;
  66         self->last_match = NULL;
  67         self->mmap_window = 32;
  68         self->cwd = NULL;
  69         self->cwdlen = 0;
  70         self->unknown_events = 0;
  71         map_groups__init(&self->kmaps);
  72
  73         if (mode == O_RDONLY && perf_session__open(self, force) < 0)
  74                 goto out_delete;
  75
  76         self->sample_type = perf_header__sample_type(&self->header);
  77 out:
  78         return self;
  79 out_free:
  80         free(self);
  81         return NULL;
  82 out_delete:
  83         perf_session__delete(self);
  84         return NULL;
  85 }
  86
  87 void perf_session__delete(struct perf_session *self)
  88 {
  89         perf_header__exit(&self->header);
  90         close(self->fd);
  91         free(self->cwd);
  92         free(self);
  93 }
  94
  95 static bool symbol__match_parent_regex(struct symbol *sym)
  96 {
  97         if (sym->name && !regexec(&parent_regex, sym->name, 0, NULL, 0))
  98                 return 1;
  99
 100         return 0;
 101 }
 102
 103 struct symbol **perf_session__resolve_callchain(struct perf_session *self,
 104                                                 struct thread *thread,
 105                                                 struct ip_callchain *chain,
 106                                                 struct symbol **parent)
 107 {
 108         u8 cpumode = PERF_RECORD_MISC_USER;
 109         struct symbol **syms = NULL;
 110         unsigned int i;
 111
 112         if (symbol_conf.use_callchain) {
 113                 syms = calloc(chain->nr, sizeof(*syms));
 114                 if (!syms) {
 115                         fprintf(stderr, "Can't allocate memory for symbols\n");
 116                         exit(-1);
 117                 }
 118         }
 119
 120         for (i = 0; i < chain->nr; i++) {
 121                 u64 ip = chain->ips[i];
 122                 struct addr_location al;
 123
 124                 if (ip >= PERF_CONTEXT_MAX) {
 125                         switch (ip) {
 126                         case PERF_CONTEXT_HV:
 127                                 cpumode = PERF_RECORD_MISC_HYPERVISOR;  break;
 128                         case PERF_CONTEXT_KERNEL:
 129                                 cpumode = PERF_RECORD_MISC_KERNEL;      break;
 130                         case PERF_CONTEXT_USER:
 131                                 cpumode = PERF_RECORD_MISC_USER;        break;
 132                         default:
 133                                 break;
 134                         }
 135                         continue;
 136                 }
 137
 138                 thread__find_addr_location(thread, self, cpumode,
 139                                            MAP__FUNCTION, ip, &al, NULL);
 140                 if (al.sym != NULL) {
 141                         if (sort__has_parent && !*parent &&
 142                             symbol__match_parent_regex(al.sym))
 143                                 *parent = al.sym;
 144                         if (!symbol_conf.use_callchain)
 145                                 break;
 146                         syms[i] = al.sym;
 147                 }
 148         }
 149
 150         return syms;
 151 }
 152
 153 static int process_event_stub(event_t *event __used,
 154                               struct perf_session *session __used)
 155 {
 156         dump_printf(": unhandled!\n");
 157         return 0;
 158 }
 159
 160 static void perf_event_ops__fill_defaults(struct perf_event_ops *handler)
 161 {
 162         if (handler->sample == NULL)
 163                 handler->sample = process_event_stub;
 164         if (handler->mmap == NULL)
 165                 handler->mmap = process_event_stub;
 166         if (handler->comm == NULL)
 167                 handler->comm = process_event_stub;
 168         if (handler->fork == NULL)
 169                 handler->fork = process_event_stub;
 170         if (handler->exit == NULL)
 171                 handler->exit = process_event_stub;
 172         if (handler->lost == NULL)
 173                 handler->lost = process_event_stub;
 174         if (handler->read == NULL)
 175                 handler->read = process_event_stub;
 176         if (handler->throttle == NULL)
 177                 handler->throttle = process_event_stub;
 178         if (handler->unthrottle == NULL)
 179                 handler->unthrottle = process_event_stub;
 180 }
 181
 182 static const char *event__name[] = {
 183         [0]                      = "TOTAL",
 184         [PERF_RECORD_MMAP]       = "MMAP",
 185         [PERF_RECORD_LOST]       = "LOST",
 186         [PERF_RECORD_COMM]       = "COMM",
 187         [PERF_RECORD_EXIT]       = "EXIT",
 188         [PERF_RECORD_THROTTLE]   = "THROTTLE",
 189         [PERF_RECORD_UNTHROTTLE] = "UNTHROTTLE",
 190         [PERF_RECORD_FORK]       = "FORK",
 191         [PERF_RECORD_READ]       = "READ",
 192         [PERF_RECORD_SAMPLE]     = "SAMPLE",
 193 };
 194
 195 unsigned long event__total[PERF_RECORD_MAX];
 196
 197 void event__print_totals(void)
 198 {
 199         int i;
 200         for (i = 0; i < PERF_RECORD_MAX; ++i)
 201                 pr_info("%10s events: %10ld\n",
 202                         event__name[i], event__total[i]);
 203 }
 204
 205 void mem_bswap_64(void *src, int byte_size)
 206 {
 207         u64 *m = src;
 208
 209         while (byte_size > 0) {
 210                 *m = bswap_64(*m);
 211                 byte_size -= sizeof(u64);
 212                 ++m;
 213         }
 214 }
 215
 216 static void event__all64_swap(event_t *self)
 217 {
 218         struct perf_event_header *hdr = &self->header;
 219         mem_bswap_64(hdr + 1, self->header.size - sizeof(*hdr));
 220 }
 221
 222 static void event__comm_swap(event_t *self)
 223 {
 224         self->comm.pid = bswap_32(self->comm.pid);
 225         self->comm.tid = bswap_32(self->comm.tid);
 226 }
 227
 228 static void event__mmap_swap(event_t *self)
 229 {
 230         self->mmap.pid   = bswap_32(self->mmap.pid);
 231         self->mmap.tid   = bswap_32(self->mmap.tid);
 232         self->mmap.start = bswap_64(self->mmap.start);
 233         self->mmap.len   = bswap_64(self->mmap.len);
 234         self->mmap.pgoff = bswap_64(self->mmap.pgoff);
 235 }
 236
 237 static void event__task_swap(event_t *self)
 238 {
 239         self->fork.pid  = bswap_32(self->fork.pid);
 240         self->fork.tid  = bswap_32(self->fork.tid);
 241         self->fork.ppid = bswap_32(self->fork.ppid);
 242         self->fork.ptid = bswap_32(self->fork.ptid);
 243         self->fork.time = bswap_64(self->fork.time);
 244 }
 245
 246 static void event__read_swap(event_t *self)
 247 {
 248         self->read.pid          = bswap_32(self->read.pid);
 249         self->read.tid          = bswap_32(self->read.tid);
 250         self->read.value        = bswap_64(self->read.value);
 251         self->read.time_enabled = bswap_64(self->read.time_enabled);
 252         self->read.time_running = bswap_64(self->read.time_running);
 253         self->read.id           = bswap_64(self->read.id);
 254 }
 255
 256 typedef void (*event__swap_op)(event_t *self);
 257
 258 static event__swap_op event__swap_ops[] = {
 259         [PERF_RECORD_MMAP]   = event__mmap_swap,
 260         [PERF_RECORD_COMM]   = event__comm_swap,
 261         [PERF_RECORD_FORK]   = event__task_swap,
 262         [PERF_RECORD_EXIT]   = event__task_swap,
 263         [PERF_RECORD_LOST]   = event__all64_swap,
 264         [PERF_RECORD_READ]   = event__read_swap,
 265         [PERF_RECORD_SAMPLE] = event__all64_swap,
 266         [PERF_RECORD_MAX]    = NULL,
 267 };
 268
 269 static int perf_session__process_event(struct perf_session *self,
 270                                        event_t *event,
 271                                        struct perf_event_ops *ops,
 272                                        u64 offset, u64 head)
 273 {
 274         trace_event(event);
 275
 276         if (event->header.type < PERF_RECORD_MAX) {
 277                 dump_printf("%#Lx [%#x]: PERF_RECORD_%s",
 278                             offset + head, event->header.size,
 279                             event__name[event->header.type]);
 280                 ++event__total[0];
 281                 ++event__total[event->header.type];
 282         }
 283
 284         if (self->header.needs_swap && event__swap_ops[event->header.type])
 285                 event__swap_ops[event->header.type](event);
 286
 287         switch (event->header.type) {
 288         case PERF_RECORD_SAMPLE:
 289                 return ops->sample(event, self);
 290         case PERF_RECORD_MMAP:
 291                 return ops->mmap(event, self);
 292         case PERF_RECORD_COMM:
 293                 return ops->comm(event, self);
 294         case PERF_RECORD_FORK:
 295                 return ops->fork(event, self);
 296         case PERF_RECORD_EXIT:
 297                 return ops->exit(event, self);
 298         case PERF_RECORD_LOST:
 299                 return ops->lost(event, self);
 300         case PERF_RECORD_READ:
 301                 return ops->read(event, self);
 302         case PERF_RECORD_THROTTLE:
 303                 return ops->throttle(event, self);
 304         case PERF_RECORD_UNTHROTTLE:
 305                 return ops->unthrottle(event, self);
 306         default:
 307                 self->unknown_events++;
 308                 return -1;
 309         }
 310 }
 311
 312 void perf_event_header__bswap(struct perf_event_header *self)
 313 {
 314         self->type = bswap_32(self->type);
 315         self->misc = bswap_16(self->misc);
 316         self->size = bswap_16(self->size);
 317 }
 318
 319 int perf_header__read_build_ids(struct perf_header *self,
 320                                 int input, u64 offset, u64 size)
 321 {
 322         struct build_id_event bev;
 323         char filename[PATH_MAX];
 324         u64 limit = offset + size;
 325         int err = -1;
 326
 327         while (offset < limit) {
 328                 struct dso *dso;
 329                 ssize_t len;
 330                 struct list_head *head = &dsos__user;
 331
 332                 if (read(input, &bev, sizeof(bev)) != sizeof(bev))
 333                         goto out;
 334
 335                 if (self->needs_swap)
 336                         perf_event_header__bswap(&bev.header);
 337
 338                 len = bev.header.size - sizeof(bev);
 339                 if (read(input, filename, len) != len)
 340                         goto out;
 341
 342                 if (bev.header.misc & PERF_RECORD_MISC_KERNEL)
 343                         head = &dsos__kernel;
 344
 345                 dso = __dsos__findnew(head, filename);
 346                 if (dso != NULL) {
 347                         dso__set_build_id(dso, &bev.build_id);
 348                         if (head == &dsos__kernel && filename[0] == '[')
 349                                 dso->kernel = 1;
 350                 }
 351
 352                 offset += bev.header.size;
 353         }
 354         err = 0;
 355 out:
 356         return err;
 357 }
 358
 359 static struct thread *perf_session__register_idle_thread(struct perf_session *self)
 360 {
 361         struct thread *thread = perf_session__findnew(self, 0);
 362
 363         if (thread == NULL || thread__set_comm(thread, "swapper")) {
 364                 pr_err("problem inserting idle task.\n");
 365                 thread = NULL;
 366         }
 367
 368         return thread;
 369 }
 370
 371 int perf_session__process_events(struct perf_session *self,
 372                                  struct perf_event_ops *ops)
 373 {
 374         int err, mmap_prot, mmap_flags;
 375         u64 head, shift;
 376         u64 offset = 0;
 377         size_t  page_size;
 378         event_t *event;
 379         uint32_t size;
 380         char *buf;
 381
 382         if (perf_session__register_idle_thread(self) == NULL)
 383                 return -ENOMEM;
 384
 385         perf_event_ops__fill_defaults(ops);
 386
 387         page_size = getpagesize();
 388
 389         head = self->header.data_offset;
 390
 391         if (!symbol_conf.full_paths) {
 392                 char bf[PATH_MAX];
 393
 394                 if (getcwd(bf, sizeof(bf)) == NULL) {
 395                         err = -errno;
 396 out_getcwd_err:
 397                         pr_err("failed to get the current directory\n");
 398                         goto out_err;
 399                 }
 400                 self->cwd = strdup(bf);
 401                 if (self->cwd == NULL) {
 402                         err = -ENOMEM;
 403                         goto out_getcwd_err;
 404                 }
 405                 self->cwdlen = strlen(self->cwd);
 406         }
 407
 408         shift = page_size * (head / page_size);
 409         offset += shift;
 410         head -= shift;
 411
 412         mmap_prot  = PROT_READ;
 413         mmap_flags = MAP_SHARED;
 414
 415         if (self->header.needs_swap) {
 416                 mmap_prot  |= PROT_WRITE;
 417                 mmap_flags = MAP_PRIVATE;
 418         }
 419 remap:
 420         buf = mmap(NULL, page_size * self->mmap_window, mmap_prot,
 421                    mmap_flags, self->fd, offset);
 422         if (buf == MAP_FAILED) {
 423                 pr_err("failed to mmap file\n");
 424                 err = -errno;
 425                 goto out_err;
 426         }
 427
 428 more:
 429         event = (event_t *)(buf + head);
 430
 431         if (self->header.needs_swap)
 432                 perf_event_header__bswap(&event->header);
 433         size = event->header.size;
 434         if (size == 0)
 435                 size = 8;
 436
 437         if (head + event->header.size >= page_size * self->mmap_window) {
 438                 int munmap_ret;
 439
 440                 shift = page_size * (head / page_size);
 441
 442                 munmap_ret = munmap(buf, page_size * self->mmap_window);
 443                 assert(munmap_ret == 0);
 444
 445                 offset += shift;
 446                 head -= shift;
 447                 goto remap;
 448         }
 449
 450         size = event->header.size;
 451
 452         dump_printf("\n%#Lx [%#x]: event: %d\n",
 453                     offset + head, event->header.size, event->header.type);
 454
 455         if (size == 0 ||
 456             perf_session__process_event(self, event, ops, offset, head) < 0) {
 457                 dump_printf("%#Lx [%#x]: skipping unknown header type: %d\n",
 458                             offset + head, event->header.size,
 459                             event->header.type);
 460                 /*
 461                  * assume we lost track of the stream, check alignment, and
 462                  * increment a single u64 in the hope to catch on again 'soon'.
 463                  */
 464                 if (unlikely(head & 7))
 465                         head &= ~7ULL;
 466
 467                 size = 8;
 468         }
 469
 470         head += size;
 471
 472         if (offset + head >= self->header.data_offset + self->header.data_size)
 473                 goto done;
 474
 475         if (offset + head < self->size)
 476                 goto more;
 477 done:
 478         err = 0;
 479 out_err:
 480         return err;
 481 }
 482
 483 bool perf_session__has_traces(struct perf_session *self, const char *msg)
 484 {
 485         if (!(self->sample_type & PERF_SAMPLE_RAW)) {
 486                 pr_err("No trace sample to read. Did you call 'perf %s'?\n", msg);
 487                 return false;
 488         }
 489
 490         return true;
 491 }
 492
 493 int perf_session__set_kallsyms_ref_reloc_sym(struct perf_session *self,
 494                                              const char *symbol_name,
 495                                              u64 addr)
 496 {
 497         char *bracket;
 498
 499         self->ref_reloc_sym.name = strdup(symbol_name);
 500         if (self->ref_reloc_sym.name == NULL)
 501                 return -ENOMEM;
 502
 503         bracket = strchr(self->ref_reloc_sym.name, ']');
 504         if (bracket)
 505                 *bracket = '\0';
 506
 507         self->ref_reloc_sym.addr = addr;
 508         return 0;
 509 }
 510
 511 static u64 map__reloc_map_ip(struct map *map, u64 ip)
 512 {
 513         return ip + (s64)map->pgoff;
 514 }
 515
 516 static u64 map__reloc_unmap_ip(struct map *map, u64 ip)
 517 {
 518         return ip - (s64)map->pgoff;
 519 }
 520
 521 void perf_session__reloc_vmlinux_maps(struct perf_session *self,
 522                                       u64 unrelocated_addr)
 523 {
 524         enum map_type type;
 525         s64 reloc = unrelocated_addr - self->ref_reloc_sym.addr;
 526
 527         if (!reloc)
 528                 return;
 529
 530         for (type = 0; type < MAP__NR_TYPES; ++type) {
 531                 struct map *map = self->vmlinux_maps[type];
 532
 533                 map->map_ip = map__reloc_map_ip;
 534                 map->unmap_ip = map__reloc_unmap_ip;
 535                 map->pgoff = reloc;
 536         }
 537 }