tools/perf/util/session.c

   1 #define _FILE_OFFSET_BITS 64
   2
   3 #include <linux/kernel.h>
   4
   5 #include <byteswap.h>
   6 #include <unistd.h>
   7 #include <sys/types.h>
   8
   9 #include "session.h"
  10 #include "sort.h"
  11 #include "util.h"
  12
  13 static int perf_session__open(struct perf_session *self, bool force)
  14 {
  15         struct stat input_stat;
  16
  17         self->fd = open(self->filename, O_RDONLY);
  18         if (self->fd < 0) {
  19                 pr_err("failed to open file: %s", self->filename);
  20                 if (!strcmp(self->filename, "perf.data"))
  21                         pr_err("  (try 'perf record' first)");
  22                 pr_err("\n");
  23                 return -errno;
  24         }
  25
  26         if (fstat(self->fd, &input_stat) < 0)
  27                 goto out_close;
  28
  29         if (!force && input_stat.st_uid && (input_stat.st_uid != geteuid())) {
  30                 pr_err("file %s not owned by current user or root\n",
  31                        self->filename);
  32                 goto out_close;
  33         }
  34
  35         if (!input_stat.st_size) {
  36                 pr_info("zero-sized file (%s), nothing to do!\n",
  37                         self->filename);
  38                 goto out_close;
  39         }
  40
  41         if (perf_header__read(&self->header, self->fd) < 0) {
  42                 pr_err("incompatible file format");
  43                 goto out_close;
  44         }
  45
  46         self->size = input_stat.st_size;
  47         return 0;
  48
  49 out_close:
  50         close(self->fd);
  51         self->fd = -1;
  52         return -1;
  53 }
  54
  55 static inline int perf_session__create_kernel_maps(struct perf_session *self)
  56 {
  57         return map_groups__create_kernel_maps(&self->kmaps, self->vmlinux_maps);
  58 }
  59
  60 struct perf_session *perf_session__new(const char *filename, int mode, bool force)
  61 {
  62         size_t len = filename ? strlen(filename) + 1 : 0;
  63         struct perf_session *self = zalloc(sizeof(*self) + len);
  64
  65         if (self == NULL)
  66                 goto out;
  67
  68         if (perf_header__init(&self->header) < 0)
  69                 goto out_free;
  70
  71         memcpy(self->filename, filename, len);
  72         self->threads = RB_ROOT;
  73         self->last_match = NULL;
  74         self->mmap_window = 32;
  75         self->cwd = NULL;
  76         self->cwdlen = 0;
  77         self->unknown_events = 0;
  78         map_groups__init(&self->kmaps);
  79
  80         if (mode == O_RDONLY) {
  81                 if (perf_session__open(self, force) < 0)
  82                         goto out_delete;
  83         } else if (mode == O_WRONLY) {
  84                 /*
  85                  * In O_RDONLY mode this will be performed when reading the
  86                  * kernel MMAP event, in event__process_mmap().
  87                  */
  88                 if (perf_session__create_kernel_maps(self) < 0)
  89                         goto out_delete;
  90         }
  91
  92         self->sample_type = perf_header__sample_type(&self->header);
  93 out:
  94         return self;
  95 out_free:
  96         free(self);
  97         return NULL;
  98 out_delete:
  99         perf_session__delete(self);
 100         return NULL;
 101 }
 102
 103 void perf_session__delete(struct perf_session *self)
 104 {
 105         perf_header__exit(&self->header);
 106         close(self->fd);
 107         free(self->cwd);
 108         free(self);
 109 }
 110
 111 static bool symbol__match_parent_regex(struct symbol *sym)
 112 {
 113         if (sym->name && !regexec(&parent_regex, sym->name, 0, NULL, 0))
 114                 return 1;
 115
 116         return 0;
 117 }
 118
 119 struct symbol **perf_session__resolve_callchain(struct perf_session *self,
 120                                                 struct thread *thread,
 121                                                 struct ip_callchain *chain,
 122                                                 struct symbol **parent)
 123 {
 124         u8 cpumode = PERF_RECORD_MISC_USER;
 125         struct symbol **syms = NULL;
 126         unsigned int i;
 127
 128         if (symbol_conf.use_callchain) {
 129                 syms = calloc(chain->nr, sizeof(*syms));
 130                 if (!syms) {
 131                         fprintf(stderr, "Can't allocate memory for symbols\n");
 132                         exit(-1);
 133                 }
 134         }
 135
 136         for (i = 0; i < chain->nr; i++) {
 137                 u64 ip = chain->ips[i];
 138                 struct addr_location al;
 139
 140                 if (ip >= PERF_CONTEXT_MAX) {
 141                         switch (ip) {
 142                         case PERF_CONTEXT_HV:
 143                                 cpumode = PERF_RECORD_MISC_HYPERVISOR;  break;
 144                         case PERF_CONTEXT_KERNEL:
 145                                 cpumode = PERF_RECORD_MISC_KERNEL;      break;
 146                         case PERF_CONTEXT_USER:
 147                                 cpumode = PERF_RECORD_MISC_USER;        break;
 148                         default:
 149                                 break;
 150                         }
 151                         continue;
 152                 }
 153
 154                 thread__find_addr_location(thread, self, cpumode,
 155                                            MAP__FUNCTION, ip, &al, NULL);
 156                 if (al.sym != NULL) {
 157                         if (sort__has_parent && !*parent &&
 158                             symbol__match_parent_regex(al.sym))
 159                                 *parent = al.sym;
 160                         if (!symbol_conf.use_callchain)
 161                                 break;
 162                         syms[i] = al.sym;
 163                 }
 164         }
 165
 166         return syms;
 167 }
 168
 169 static int process_event_stub(event_t *event __used,
 170                               struct perf_session *session __used)
 171 {
 172         dump_printf(": unhandled!\n");
 173         return 0;
 174 }
 175
 176 static void perf_event_ops__fill_defaults(struct perf_event_ops *handler)
 177 {
 178         if (handler->sample == NULL)
 179                 handler->sample = process_event_stub;
 180         if (handler->mmap == NULL)
 181                 handler->mmap = process_event_stub;
 182         if (handler->comm == NULL)
 183                 handler->comm = process_event_stub;
 184         if (handler->fork == NULL)
 185                 handler->fork = process_event_stub;
 186         if (handler->exit == NULL)
 187                 handler->exit = process_event_stub;
 188         if (handler->lost == NULL)
 189                 handler->lost = process_event_stub;
 190         if (handler->read == NULL)
 191                 handler->read = process_event_stub;
 192         if (handler->throttle == NULL)
 193                 handler->throttle = process_event_stub;
 194         if (handler->unthrottle == NULL)
 195                 handler->unthrottle = process_event_stub;
 196 }
 197
 198 static const char *event__name[] = {
 199         [0]                      = "TOTAL",
 200         [PERF_RECORD_MMAP]       = "MMAP",
 201         [PERF_RECORD_LOST]       = "LOST",
 202         [PERF_RECORD_COMM]       = "COMM",
 203         [PERF_RECORD_EXIT]       = "EXIT",
 204         [PERF_RECORD_THROTTLE]   = "THROTTLE",
 205         [PERF_RECORD_UNTHROTTLE] = "UNTHROTTLE",
 206         [PERF_RECORD_FORK]       = "FORK",
 207         [PERF_RECORD_READ]       = "READ",
 208         [PERF_RECORD_SAMPLE]     = "SAMPLE",
 209 };
 210
 211 unsigned long event__total[PERF_RECORD_MAX];
 212
 213 void event__print_totals(void)
 214 {
 215         int i;
 216         for (i = 0; i < PERF_RECORD_MAX; ++i)
 217                 pr_info("%10s events: %10ld\n",
 218                         event__name[i], event__total[i]);
 219 }
 220
 221 void mem_bswap_64(void *src, int byte_size)
 222 {
 223         u64 *m = src;
 224
 225         while (byte_size > 0) {
 226                 *m = bswap_64(*m);
 227                 byte_size -= sizeof(u64);
 228                 ++m;
 229         }
 230 }
 231
 232 static void event__all64_swap(event_t *self)
 233 {
 234         struct perf_event_header *hdr = &self->header;
 235         mem_bswap_64(hdr + 1, self->header.size - sizeof(*hdr));
 236 }
 237
 238 static void event__comm_swap(event_t *self)
 239 {
 240         self->comm.pid = bswap_32(self->comm.pid);
 241         self->comm.tid = bswap_32(self->comm.tid);
 242 }
 243
 244 static void event__mmap_swap(event_t *self)
 245 {
 246         self->mmap.pid   = bswap_32(self->mmap.pid);
 247         self->mmap.tid   = bswap_32(self->mmap.tid);
 248         self->mmap.start = bswap_64(self->mmap.start);
 249         self->mmap.len   = bswap_64(self->mmap.len);
 250         self->mmap.pgoff = bswap_64(self->mmap.pgoff);
 251 }
 252
 253 static void event__task_swap(event_t *self)
 254 {
 255         self->fork.pid  = bswap_32(self->fork.pid);
 256         self->fork.tid  = bswap_32(self->fork.tid);
 257         self->fork.ppid = bswap_32(self->fork.ppid);
 258         self->fork.ptid = bswap_32(self->fork.ptid);
 259         self->fork.time = bswap_64(self->fork.time);
 260 }
 261
 262 static void event__read_swap(event_t *self)
 263 {
 264         self->read.pid          = bswap_32(self->read.pid);
 265         self->read.tid          = bswap_32(self->read.tid);
 266         self->read.value        = bswap_64(self->read.value);
 267         self->read.time_enabled = bswap_64(self->read.time_enabled);
 268         self->read.time_running = bswap_64(self->read.time_running);
 269         self->read.id           = bswap_64(self->read.id);
 270 }
 271
 272 typedef void (*event__swap_op)(event_t *self);
 273
 274 static event__swap_op event__swap_ops[] = {
 275         [PERF_RECORD_MMAP]   = event__mmap_swap,
 276         [PERF_RECORD_COMM]   = event__comm_swap,
 277         [PERF_RECORD_FORK]   = event__task_swap,
 278         [PERF_RECORD_EXIT]   = event__task_swap,
 279         [PERF_RECORD_LOST]   = event__all64_swap,
 280         [PERF_RECORD_READ]   = event__read_swap,
 281         [PERF_RECORD_SAMPLE] = event__all64_swap,
 282         [PERF_RECORD_MAX]    = NULL,
 283 };
 284
 285 static int perf_session__process_event(struct perf_session *self,
 286                                        event_t *event,
 287                                        struct perf_event_ops *ops,
 288                                        u64 offset, u64 head)
 289 {
 290         trace_event(event);
 291
 292         if (event->header.type < PERF_RECORD_MAX) {
 293                 dump_printf("%#Lx [%#x]: PERF_RECORD_%s",
 294                             offset + head, event->header.size,
 295                             event__name[event->header.type]);
 296                 ++event__total[0];
 297                 ++event__total[event->header.type];
 298         }
 299
 300         if (self->header.needs_swap && event__swap_ops[event->header.type])
 301                 event__swap_ops[event->header.type](event);
 302
 303         switch (event->header.type) {
 304         case PERF_RECORD_SAMPLE:
 305                 return ops->sample(event, self);
 306         case PERF_RECORD_MMAP:
 307                 return ops->mmap(event, self);
 308         case PERF_RECORD_COMM:
 309                 return ops->comm(event, self);
 310         case PERF_RECORD_FORK:
 311                 return ops->fork(event, self);
 312         case PERF_RECORD_EXIT:
 313                 return ops->exit(event, self);
 314         case PERF_RECORD_LOST:
 315                 return ops->lost(event, self);
 316         case PERF_RECORD_READ:
 317                 return ops->read(event, self);
 318         case PERF_RECORD_THROTTLE:
 319                 return ops->throttle(event, self);
 320         case PERF_RECORD_UNTHROTTLE:
 321                 return ops->unthrottle(event, self);
 322         default:
 323                 self->unknown_events++;
 324                 return -1;
 325         }
 326 }
 327
 328 void perf_event_header__bswap(struct perf_event_header *self)
 329 {
 330         self->type = bswap_32(self->type);
 331         self->misc = bswap_16(self->misc);
 332         self->size = bswap_16(self->size);
 333 }
 334
 335 int perf_header__read_build_ids(struct perf_header *self,
 336                                 int input, u64 offset, u64 size)
 337 {
 338         struct build_id_event bev;
 339         char filename[PATH_MAX];
 340         u64 limit = offset + size;
 341         int err = -1;
 342
 343         while (offset < limit) {
 344                 struct dso *dso;
 345                 ssize_t len;
 346                 struct list_head *head = &dsos__user;
 347
 348                 if (read(input, &bev, sizeof(bev)) != sizeof(bev))
 349                         goto out;
 350
 351                 if (self->needs_swap)
 352                         perf_event_header__bswap(&bev.header);
 353
 354                 len = bev.header.size - sizeof(bev);
 355                 if (read(input, filename, len) != len)
 356                         goto out;
 357
 358                 if (bev.header.misc & PERF_RECORD_MISC_KERNEL)
 359                         head = &dsos__kernel;
 360
 361                 dso = __dsos__findnew(head, filename);
 362                 if (dso != NULL) {
 363                         dso__set_build_id(dso, &bev.build_id);
 364                         if (head == &dsos__kernel && filename[0] == '[')
 365                                 dso->kernel = 1;
 366                 }
 367
 368                 offset += bev.header.size;
 369         }
 370         err = 0;
 371 out:
 372         return err;
 373 }
 374
 375 static struct thread *perf_session__register_idle_thread(struct perf_session *self)
 376 {
 377         struct thread *thread = perf_session__findnew(self, 0);
 378
 379         if (thread == NULL || thread__set_comm(thread, "swapper")) {
 380                 pr_err("problem inserting idle task.\n");
 381                 thread = NULL;
 382         }
 383
 384         return thread;
 385 }
 386
 387 int __perf_session__process_events(struct perf_session *self,
 388                                    u64 data_offset, u64 data_size,
 389                                    u64 file_size, struct perf_event_ops *ops)
 390 {
 391         int err, mmap_prot, mmap_flags;
 392         u64 head, shift;
 393         u64 offset = 0;
 394         size_t  page_size;
 395         event_t *event;
 396         uint32_t size;
 397         char *buf;
 398
 399         perf_event_ops__fill_defaults(ops);
 400
 401         page_size = sysconf(_SC_PAGESIZE);
 402
 403         head = data_offset;
 404         shift = page_size * (head / page_size);
 405         offset += shift;
 406         head -= shift;
 407
 408         mmap_prot  = PROT_READ;
 409         mmap_flags = MAP_SHARED;
 410
 411         if (self->header.needs_swap) {
 412                 mmap_prot  |= PROT_WRITE;
 413                 mmap_flags = MAP_PRIVATE;
 414         }
 415 remap:
 416         buf = mmap(NULL, page_size * self->mmap_window, mmap_prot,
 417                    mmap_flags, self->fd, offset);
 418         if (buf == MAP_FAILED) {
 419                 pr_err("failed to mmap file\n");
 420                 err = -errno;
 421                 goto out_err;
 422         }
 423
 424 more:
 425         event = (event_t *)(buf + head);
 426
 427         if (self->header.needs_swap)
 428                 perf_event_header__bswap(&event->header);
 429         size = event->header.size;
 430         if (size == 0)
 431                 size = 8;
 432
 433         if (head + event->header.size >= page_size * self->mmap_window) {
 434                 int munmap_ret;
 435
 436                 shift = page_size * (head / page_size);
 437
 438                 munmap_ret = munmap(buf, page_size * self->mmap_window);
 439                 assert(munmap_ret == 0);
 440
 441                 offset += shift;
 442                 head -= shift;
 443                 goto remap;
 444         }
 445
 446         size = event->header.size;
 447
 448         dump_printf("\n%#Lx [%#x]: event: %d\n",
 449                     offset + head, event->header.size, event->header.type);
 450
 451         if (size == 0 ||
 452             perf_session__process_event(self, event, ops, offset, head) < 0) {
 453                 dump_printf("%#Lx [%#x]: skipping unknown header type: %d\n",
 454                             offset + head, event->header.size,
 455                             event->header.type);
 456                 /*
 457                  * assume we lost track of the stream, check alignment, and
 458                  * increment a single u64 in the hope to catch on again 'soon'.
 459                  */
 460                 if (unlikely(head & 7))
 461                         head &= ~7ULL;
 462
 463                 size = 8;
 464         }
 465
 466         head += size;
 467
 468         if (offset + head >= data_offset + data_size)
 469                 goto done;
 470
 471         if (offset + head < file_size)
 472                 goto more;
 473 done:
 474         err = 0;
 475 out_err:
 476         return err;
 477 }
 478
 479 int perf_session__process_events(struct perf_session *self,
 480                                  struct perf_event_ops *ops)
 481 {
 482         int err;
 483
 484         if (perf_session__register_idle_thread(self) == NULL)
 485                 return -ENOMEM;
 486
 487         if (!symbol_conf.full_paths) {
 488                 char bf[PATH_MAX];
 489
 490                 if (getcwd(bf, sizeof(bf)) == NULL) {
 491                         err = -errno;
 492 out_getcwd_err:
 493                         pr_err("failed to get the current directory\n");
 494                         goto out_err;
 495                 }
 496                 self->cwd = strdup(bf);
 497                 if (self->cwd == NULL) {
 498                         err = -ENOMEM;
 499                         goto out_getcwd_err;
 500                 }
 501                 self->cwdlen = strlen(self->cwd);
 502         }
 503
 504         err = __perf_session__process_events(self, self->header.data_offset,
 505                                              self->header.data_size,
 506                                              self->size, ops);
 507 out_err:
 508         return err;
 509 }
 510
 511 bool perf_session__has_traces(struct perf_session *self, const char *msg)
 512 {
 513         if (!(self->sample_type & PERF_SAMPLE_RAW)) {
 514                 pr_err("No trace sample to read. Did you call 'perf %s'?\n", msg);
 515                 return false;
 516         }
 517
 518         return true;
 519 }
 520
 521 int perf_session__set_kallsyms_ref_reloc_sym(struct perf_session *self,
 522                                              const char *symbol_name,
 523                                              u64 addr)
 524 {
 525         char *bracket;
 526         enum map_type i;
 527
 528         self->ref_reloc_sym.name = strdup(symbol_name);
 529         if (self->ref_reloc_sym.name == NULL)
 530                 return -ENOMEM;
 531
 532         bracket = strchr(self->ref_reloc_sym.name, ']');
 533         if (bracket)
 534                 *bracket = '\0';
 535
 536         self->ref_reloc_sym.addr = addr;
 537
 538         for (i = 0; i < MAP__NR_TYPES; ++i) {
 539                 struct kmap *kmap = map__kmap(self->vmlinux_maps[i]);
 540                 kmap->ref_reloc_sym = &self->ref_reloc_sym;
 541         }
 542
 543         return 0;
 544 }
 545
 546 static u64 map__reloc_map_ip(struct map *map, u64 ip)
 547 {
 548         return ip + (s64)map->pgoff;
 549 }
 550
 551 static u64 map__reloc_unmap_ip(struct map *map, u64 ip)
 552 {
 553         return ip - (s64)map->pgoff;
 554 }
 555
 556 void map__reloc_vmlinux(struct map *self)
 557 {
 558         struct kmap *kmap = map__kmap(self);
 559         s64 reloc;
 560
 561         if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->unrelocated_addr)
 562                 return;
 563
 564         reloc = (kmap->ref_reloc_sym->unrelocated_addr -
 565                  kmap->ref_reloc_sym->addr);
 566
 567         if (!reloc)
 568                 return;
 569
 570         self->map_ip   = map__reloc_map_ip;
 571         self->unmap_ip = map__reloc_unmap_ip;
 572         self->pgoff    = reloc;
 573 }