tools/perf/util/header.c

   1 #include <sys/types.h>
   2 #include <byteswap.h>
   3 #include <unistd.h>
   4 #include <stdio.h>
   5 #include <stdlib.h>
   6 #include <linux/list.h>
   7 #include <linux/kernel.h>
   8
   9 #include "util.h"
  10 #include "header.h"
  11 #include "../perf.h"
  12 #include "trace-event.h"
  13 #include "session.h"
  14 #include "symbol.h"
  15 #include "debug.h"
  16
  17 /*
  18  * Create new perf.data header attribute:
  19  */
  20 struct perf_header_attr *perf_header_attr__new(struct perf_event_attr *attr)
  21 {
  22         struct perf_header_attr *self = malloc(sizeof(*self));
  23
  24         if (self != NULL) {
  25                 self->attr = *attr;
  26                 self->ids  = 0;
  27                 self->size = 1;
  28                 self->id   = malloc(sizeof(u64));
  29                 if (self->id == NULL) {
  30                         free(self);
  31                         self = NULL;
  32                 }
  33         }
  34
  35         return self;
  36 }
  37
  38 void perf_header_attr__delete(struct perf_header_attr *self)
  39 {
  40         free(self->id);
  41         free(self);
  42 }
  43
  44 int perf_header_attr__add_id(struct perf_header_attr *self, u64 id)
  45 {
  46         int pos = self->ids;
  47
  48         self->ids++;
  49         if (self->ids > self->size) {
  50                 int nsize = self->size * 2;
  51                 u64 *nid = realloc(self->id, nsize * sizeof(u64));
  52
  53                 if (nid == NULL)
  54                         return -1;
  55
  56                 self->size = nsize;
  57                 self->id = nid;
  58         }
  59         self->id[pos] = id;
  60         return 0;
  61 }
  62
  63 int perf_header__init(struct perf_header *self)
  64 {
  65         self->size = 1;
  66         self->attr = malloc(sizeof(void *));
  67         return self->attr == NULL ? -ENOMEM : 0;
  68 }
  69
  70 void perf_header__exit(struct perf_header *self)
  71 {
  72         int i;
  73         for (i = 0; i < self->attrs; ++i)
  74                 perf_header_attr__delete(self->attr[i]);
  75         free(self->attr);
  76 }
  77
  78 int perf_header__add_attr(struct perf_header *self,
  79                           struct perf_header_attr *attr)
  80 {
  81         if (self->frozen)
  82                 return -1;
  83
  84         if (self->attrs == self->size) {
  85                 int nsize = self->size * 2;
  86                 struct perf_header_attr **nattr;
  87
  88                 nattr = realloc(self->attr, nsize * sizeof(void *));
  89                 if (nattr == NULL)
  90                         return -1;
  91
  92                 self->size = nsize;
  93                 self->attr = nattr;
  94         }
  95
  96         self->attr[self->attrs++] = attr;
  97         return 0;
  98 }
  99
 100 #define MAX_EVENT_NAME 64
 101
 102 struct perf_trace_event_type {
 103         u64     event_id;
 104         char    name[MAX_EVENT_NAME];
 105 };
 106
 107 static int event_count;
 108 static struct perf_trace_event_type *events;
 109
 110 int perf_header__push_event(u64 id, const char *name)
 111 {
 112         if (strlen(name) > MAX_EVENT_NAME)
 113                 pr_warning("Event %s will be truncated\n", name);
 114
 115         if (!events) {
 116                 events = malloc(sizeof(struct perf_trace_event_type));
 117                 if (events == NULL)
 118                         return -ENOMEM;
 119         } else {
 120                 struct perf_trace_event_type *nevents;
 121
 122                 nevents = realloc(events, (event_count + 1) * sizeof(*events));
 123                 if (nevents == NULL)
 124                         return -ENOMEM;
 125                 events = nevents;
 126         }
 127         memset(&events[event_count], 0, sizeof(struct perf_trace_event_type));
 128         events[event_count].event_id = id;
 129         strncpy(events[event_count].name, name, MAX_EVENT_NAME - 1);
 130         event_count++;
 131         return 0;
 132 }
 133
 134 char *perf_header__find_event(u64 id)
 135 {
 136         int i;
 137         for (i = 0 ; i < event_count; i++) {
 138                 if (events[i].event_id == id)
 139                         return events[i].name;
 140         }
 141         return NULL;
 142 }
 143
 144 static const char *__perf_magic = "PERFFILE";
 145
 146 #define PERF_MAGIC      (*(u64 *)__perf_magic)
 147
 148 struct perf_file_attr {
 149         struct perf_event_attr  attr;
 150         struct perf_file_section        ids;
 151 };
 152
 153 void perf_header__set_feat(struct perf_header *self, int feat)
 154 {
 155         set_bit(feat, self->adds_features);
 156 }
 157
 158 bool perf_header__has_feat(const struct perf_header *self, int feat)
 159 {
 160         return test_bit(feat, self->adds_features);
 161 }
 162
 163 static int do_write(int fd, const void *buf, size_t size)
 164 {
 165         while (size) {
 166                 int ret = write(fd, buf, size);
 167
 168                 if (ret < 0)
 169                         return -errno;
 170
 171                 size -= ret;
 172                 buf += ret;
 173         }
 174
 175         return 0;
 176 }
 177
 178 #define NAME_ALIGN 64
 179
 180 static int write_padded(int fd, const void *bf, size_t count,
 181                         size_t count_aligned)
 182 {
 183         static const char zero_buf[NAME_ALIGN];
 184         int err = do_write(fd, bf, count);
 185
 186         if (!err)
 187                 err = do_write(fd, zero_buf, count_aligned - count);
 188
 189         return err;
 190 }
 191
 192 #define dsos__for_each_with_build_id(pos, head) \
 193         list_for_each_entry(pos, head, node)    \
 194                 if (!pos->has_build_id)         \
 195                         continue;               \
 196                 else
 197
 198 static int __dsos__write_buildid_table(struct list_head *head, u16 misc, int fd)
 199 {
 200         struct dso *pos;
 201
 202         dsos__for_each_with_build_id(pos, head) {
 203                 int err;
 204                 struct build_id_event b;
 205                 size_t len = pos->long_name_len + 1;
 206
 207                 len = ALIGN(len, NAME_ALIGN);
 208                 memset(&b, 0, sizeof(b));
 209                 memcpy(&b.build_id, pos->build_id, sizeof(pos->build_id));
 210                 b.header.misc = misc;
 211                 b.header.size = sizeof(b) + len;
 212                 err = do_write(fd, &b, sizeof(b));
 213                 if (err < 0)
 214                         return err;
 215                 err = write_padded(fd, pos->long_name,
 216                                    pos->long_name_len + 1, len);
 217                 if (err < 0)
 218                         return err;
 219         }
 220
 221         return 0;
 222 }
 223
 224 static int dsos__write_buildid_table(int fd)
 225 {
 226         int err = __dsos__write_buildid_table(&dsos__kernel,
 227                                               PERF_RECORD_MISC_KERNEL, fd);
 228         if (err == 0)
 229                 err = __dsos__write_buildid_table(&dsos__user,
 230                                                   PERF_RECORD_MISC_USER, fd);
 231         return err;
 232 }
 233
 234 static int dso__cache_build_id(struct dso *self, const char *debugdir)
 235 {
 236         const size_t size = PATH_MAX;
 237         char *filename = malloc(size),
 238              *linkname = malloc(size), *targetname, *sbuild_id;
 239         int len, err = -1;
 240
 241         if (filename == NULL || linkname == NULL)
 242                 goto out_free;
 243
 244         len = snprintf(filename, size, "%s%s", debugdir, self->long_name);
 245         if (mkdir_p(filename, 0755))
 246                 goto out_free;
 247
 248         len += snprintf(filename + len, sizeof(filename) - len, "/");
 249         sbuild_id = filename + len;
 250         build_id__sprintf(self->build_id, sizeof(self->build_id), sbuild_id);
 251
 252         if (access(filename, F_OK) && link(self->long_name, filename) &&
 253             copyfile(self->long_name, filename))
 254                 goto out_free;
 255
 256         len = snprintf(linkname, size, "%s/.build-id/%.2s",
 257                        debugdir, sbuild_id);
 258
 259         if (access(linkname, X_OK) && mkdir_p(linkname, 0755))
 260                 goto out_free;
 261
 262         snprintf(linkname + len, size - len, "/%s", sbuild_id + 2);
 263         targetname = filename + strlen(debugdir) - 5;
 264         memcpy(targetname, "../..", 5);
 265
 266         if (symlink(targetname, linkname) == 0)
 267                 err = 0;
 268 out_free:
 269         free(filename);
 270         free(linkname);
 271         return err;
 272 }
 273
 274 static int __dsos__cache_build_ids(struct list_head *head, const char *debugdir)
 275 {
 276         struct dso *pos;
 277         int err = 0;
 278
 279         dsos__for_each_with_build_id(pos, head)
 280                 if (dso__cache_build_id(pos, debugdir))
 281                         err = -1;
 282
 283         return err;
 284 }
 285
 286 static int dsos__cache_build_ids(void)
 287 {
 288         int err_kernel, err_user;
 289         char debugdir[PATH_MAX];
 290
 291         snprintf(debugdir, sizeof(debugdir), "%s/%s", getenv("HOME"),
 292                  DEBUG_CACHE_DIR);
 293
 294         if (mkdir(debugdir, 0755) != 0 && errno != EEXIST)
 295                 return -1;
 296
 297         err_kernel = __dsos__cache_build_ids(&dsos__kernel, debugdir);
 298         err_user   = __dsos__cache_build_ids(&dsos__user, debugdir);
 299         return err_kernel || err_user ? -1 : 0;
 300 }
 301
 302 static int perf_header__adds_write(struct perf_header *self, int fd)
 303 {
 304         int nr_sections;
 305         struct perf_file_section *feat_sec;
 306         int sec_size;
 307         u64 sec_start;
 308         int idx = 0, err;
 309
 310         if (dsos__read_build_ids())
 311                 perf_header__set_feat(self, HEADER_BUILD_ID);
 312
 313         nr_sections = bitmap_weight(self->adds_features, HEADER_FEAT_BITS);
 314         if (!nr_sections)
 315                 return 0;
 316
 317         feat_sec = calloc(sizeof(*feat_sec), nr_sections);
 318         if (feat_sec == NULL)
 319                 return -ENOMEM;
 320
 321         sec_size = sizeof(*feat_sec) * nr_sections;
 322
 323         sec_start = self->data_offset + self->data_size;
 324         lseek(fd, sec_start + sec_size, SEEK_SET);
 325
 326         if (perf_header__has_feat(self, HEADER_TRACE_INFO)) {
 327                 struct perf_file_section *trace_sec;
 328
 329                 trace_sec = &feat_sec[idx++];
 330
 331                 /* Write trace info */
 332                 trace_sec->offset = lseek(fd, 0, SEEK_CUR);
 333                 read_tracing_data(fd, attrs, nr_counters);
 334                 trace_sec->size = lseek(fd, 0, SEEK_CUR) - trace_sec->offset;
 335         }
 336
 337
 338         if (perf_header__has_feat(self, HEADER_BUILD_ID)) {
 339                 struct perf_file_section *buildid_sec;
 340
 341                 buildid_sec = &feat_sec[idx++];
 342
 343                 /* Write build-ids */
 344                 buildid_sec->offset = lseek(fd, 0, SEEK_CUR);
 345                 err = dsos__write_buildid_table(fd);
 346                 if (err < 0) {
 347                         pr_debug("failed to write buildid table\n");
 348                         goto out_free;
 349                 }
 350                 buildid_sec->size = lseek(fd, 0, SEEK_CUR) - buildid_sec->offset;
 351                 dsos__cache_build_ids();
 352         }
 353
 354         lseek(fd, sec_start, SEEK_SET);
 355         err = do_write(fd, feat_sec, sec_size);
 356         if (err < 0)
 357                 pr_debug("failed to write feature section\n");
 358 out_free:
 359         free(feat_sec);
 360         return err;
 361 }
 362
 363 int perf_header__write(struct perf_header *self, int fd, bool at_exit)
 364 {
 365         struct perf_file_header f_header;
 366         struct perf_file_attr   f_attr;
 367         struct perf_header_attr *attr;
 368         int i, err;
 369
 370         lseek(fd, sizeof(f_header), SEEK_SET);
 371
 372
 373         for (i = 0; i < self->attrs; i++) {
 374                 attr = self->attr[i];
 375
 376                 attr->id_offset = lseek(fd, 0, SEEK_CUR);
 377                 err = do_write(fd, attr->id, attr->ids * sizeof(u64));
 378                 if (err < 0) {
 379                         pr_debug("failed to write perf header\n");
 380                         return err;
 381                 }
 382         }
 383
 384
 385         self->attr_offset = lseek(fd, 0, SEEK_CUR);
 386
 387         for (i = 0; i < self->attrs; i++) {
 388                 attr = self->attr[i];
 389
 390                 f_attr = (struct perf_file_attr){
 391                         .attr = attr->attr,
 392                         .ids  = {
 393                                 .offset = attr->id_offset,
 394                                 .size   = attr->ids * sizeof(u64),
 395                         }
 396                 };
 397                 err = do_write(fd, &f_attr, sizeof(f_attr));
 398                 if (err < 0) {
 399                         pr_debug("failed to write perf header attribute\n");
 400                         return err;
 401                 }
 402         }
 403
 404         self->event_offset = lseek(fd, 0, SEEK_CUR);
 405         self->event_size = event_count * sizeof(struct perf_trace_event_type);
 406         if (events) {
 407                 err = do_write(fd, events, self->event_size);
 408                 if (err < 0) {
 409                         pr_debug("failed to write perf header events\n");
 410                         return err;
 411                 }
 412         }
 413
 414         self->data_offset = lseek(fd, 0, SEEK_CUR);
 415
 416         if (at_exit) {
 417                 err = perf_header__adds_write(self, fd);
 418                 if (err < 0)
 419                         return err;
 420         }
 421
 422         f_header = (struct perf_file_header){
 423                 .magic     = PERF_MAGIC,
 424                 .size      = sizeof(f_header),
 425                 .attr_size = sizeof(f_attr),
 426                 .attrs = {
 427                         .offset = self->attr_offset,
 428                         .size   = self->attrs * sizeof(f_attr),
 429                 },
 430                 .data = {
 431                         .offset = self->data_offset,
 432                         .size   = self->data_size,
 433                 },
 434                 .event_types = {
 435                         .offset = self->event_offset,
 436                         .size   = self->event_size,
 437                 },
 438         };
 439
 440         memcpy(&f_header.adds_features, &self->adds_features, sizeof(self->adds_features));
 441
 442         lseek(fd, 0, SEEK_SET);
 443         err = do_write(fd, &f_header, sizeof(f_header));
 444         if (err < 0) {
 445                 pr_debug("failed to write perf header\n");
 446                 return err;
 447         }
 448         lseek(fd, self->data_offset + self->data_size, SEEK_SET);
 449
 450         self->frozen = 1;
 451         return 0;
 452 }
 453
 454 static int do_read(int fd, void *buf, size_t size)
 455 {
 456         while (size) {
 457                 int ret = read(fd, buf, size);
 458
 459                 if (ret <= 0)
 460                         return -1;
 461
 462                 size -= ret;
 463                 buf += ret;
 464         }
 465
 466         return 0;
 467 }
 468
 469 static int perf_header__getbuffer64(struct perf_header *self,
 470                                     int fd, void *buf, size_t size)
 471 {
 472         if (do_read(fd, buf, size))
 473                 return -1;
 474
 475         if (self->needs_swap)
 476                 mem_bswap_64(buf, size);
 477
 478         return 0;
 479 }
 480
 481 int perf_header__process_sections(struct perf_header *self, int fd,
 482                                   int (*process)(struct perf_file_section *self,
 483                                                  struct perf_header *ph,
 484                                                  int feat, int fd))
 485 {
 486         struct perf_file_section *feat_sec;
 487         int nr_sections;
 488         int sec_size;
 489         int idx = 0;
 490         int err = -1, feat = 1;
 491
 492         nr_sections = bitmap_weight(self->adds_features, HEADER_FEAT_BITS);
 493         if (!nr_sections)
 494                 return 0;
 495
 496         feat_sec = calloc(sizeof(*feat_sec), nr_sections);
 497         if (!feat_sec)
 498                 return -1;
 499
 500         sec_size = sizeof(*feat_sec) * nr_sections;
 501
 502         lseek(fd, self->data_offset + self->data_size, SEEK_SET);
 503
 504         if (perf_header__getbuffer64(self, fd, feat_sec, sec_size))
 505                 goto out_free;
 506
 507         err = 0;
 508         while (idx < nr_sections && feat < HEADER_LAST_FEATURE) {
 509                 if (perf_header__has_feat(self, feat)) {
 510                         struct perf_file_section *sec = &feat_sec[idx++];
 511
 512                         err = process(sec, self, feat, fd);
 513                         if (err < 0)
 514                                 break;
 515                 }
 516                 ++feat;
 517         }
 518 out_free:
 519         free(feat_sec);
 520         return err;
 521 }
 522
 523 int perf_file_header__read(struct perf_file_header *self,
 524                            struct perf_header *ph, int fd)
 525 {
 526         lseek(fd, 0, SEEK_SET);
 527
 528         if (do_read(fd, self, sizeof(*self)) ||
 529             memcmp(&self->magic, __perf_magic, sizeof(self->magic)))
 530                 return -1;
 531
 532         if (self->attr_size != sizeof(struct perf_file_attr)) {
 533                 u64 attr_size = bswap_64(self->attr_size);
 534
 535                 if (attr_size != sizeof(struct perf_file_attr))
 536                         return -1;
 537
 538                 mem_bswap_64(self, offsetof(struct perf_file_header,
 539                                             adds_features));
 540                 ph->needs_swap = true;
 541         }
 542
 543         if (self->size != sizeof(*self)) {
 544                 /* Support the previous format */
 545                 if (self->size == offsetof(typeof(*self), adds_features))
 546                         bitmap_zero(self->adds_features, HEADER_FEAT_BITS);
 547                 else
 548                         return -1;
 549         }
 550
 551         memcpy(&ph->adds_features, &self->adds_features,
 552                sizeof(ph->adds_features));
 553         /*
 554          * FIXME: hack that assumes that if we need swap the perf.data file
 555          * may be coming from an arch with a different word-size, ergo different
 556          * DEFINE_BITMAP format, investigate more later, but for now its mostly
 557          * safe to assume that we have a build-id section. Trace files probably
 558          * have several other issues in this realm anyway...
 559          */
 560         if (ph->needs_swap) {
 561                 memset(&ph->adds_features, 0, sizeof(ph->adds_features));
 562                 perf_header__set_feat(ph, HEADER_BUILD_ID);
 563         }
 564
 565         ph->event_offset = self->event_types.offset;
 566         ph->event_size   = self->event_types.size;
 567         ph->data_offset  = self->data.offset;
 568         ph->data_size    = self->data.size;
 569         return 0;
 570 }
 571
 572 static int perf_file_section__process(struct perf_file_section *self,
 573                                       struct perf_header *ph,
 574                                       int feat, int fd)
 575 {
 576         if (lseek(fd, self->offset, SEEK_SET) < 0) {
 577                 pr_debug("Failed to lseek to %Ld offset for feature %d, "
 578                          "continuing...\n", self->offset, feat);
 579                 return 0;
 580         }
 581
 582         switch (feat) {
 583         case HEADER_TRACE_INFO:
 584                 trace_report(fd);
 585                 break;
 586
 587         case HEADER_BUILD_ID:
 588                 if (perf_header__read_build_ids(ph, fd, self->offset, self->size))
 589                         pr_debug("Failed to read buildids, continuing...\n");
 590                 break;
 591         default:
 592                 pr_debug("unknown feature %d, continuing...\n", feat);
 593         }
 594
 595         return 0;
 596 }
 597
 598 int perf_header__read(struct perf_header *self, int fd)
 599 {
 600         struct perf_file_header f_header;
 601         struct perf_file_attr   f_attr;
 602         u64                     f_id;
 603         int nr_attrs, nr_ids, i, j;
 604
 605         if (perf_file_header__read(&f_header, self, fd) < 0) {
 606                 pr_debug("incompatible file format\n");
 607                 return -EINVAL;
 608         }
 609
 610         nr_attrs = f_header.attrs.size / sizeof(f_attr);
 611         lseek(fd, f_header.attrs.offset, SEEK_SET);
 612
 613         for (i = 0; i < nr_attrs; i++) {
 614                 struct perf_header_attr *attr;
 615                 off_t tmp;
 616
 617                 if (perf_header__getbuffer64(self, fd, &f_attr, sizeof(f_attr)))
 618                         goto out_errno;
 619
 620                 tmp = lseek(fd, 0, SEEK_CUR);
 621
 622                 attr = perf_header_attr__new(&f_attr.attr);
 623                 if (attr == NULL)
 624                          return -ENOMEM;
 625
 626                 nr_ids = f_attr.ids.size / sizeof(u64);
 627                 lseek(fd, f_attr.ids.offset, SEEK_SET);
 628
 629                 for (j = 0; j < nr_ids; j++) {
 630                         if (perf_header__getbuffer64(self, fd, &f_id, sizeof(f_id)))
 631                                 goto out_errno;
 632
 633                         if (perf_header_attr__add_id(attr, f_id) < 0) {
 634                                 perf_header_attr__delete(attr);
 635                                 return -ENOMEM;
 636                         }
 637                 }
 638                 if (perf_header__add_attr(self, attr) < 0) {
 639                         perf_header_attr__delete(attr);
 640                         return -ENOMEM;
 641                 }
 642
 643                 lseek(fd, tmp, SEEK_SET);
 644         }
 645
 646         if (f_header.event_types.size) {
 647                 lseek(fd, f_header.event_types.offset, SEEK_SET);
 648                 events = malloc(f_header.event_types.size);
 649                 if (events == NULL)
 650                         return -ENOMEM;
 651                 if (perf_header__getbuffer64(self, fd, events,
 652                                              f_header.event_types.size))
 653                         goto out_errno;
 654                 event_count =  f_header.event_types.size / sizeof(struct perf_trace_event_type);
 655         }
 656
 657         perf_header__process_sections(self, fd, perf_file_section__process);
 658
 659         lseek(fd, self->data_offset, SEEK_SET);
 660
 661         self->frozen = 1;
 662         return 0;
 663 out_errno:
 664         return -errno;
 665 }
 666
 667 u64 perf_header__sample_type(struct perf_header *header)
 668 {
 669         u64 type = 0;
 670         int i;
 671
 672         for (i = 0; i < header->attrs; i++) {
 673                 struct perf_header_attr *attr = header->attr[i];
 674
 675                 if (!type)
 676                         type = attr->attr.sample_type;
 677                 else if (type != attr->attr.sample_type)
 678                         die("non matching sample_type");
 679         }
 680
 681         return type;
 682 }
 683
 684 struct perf_event_attr *
 685 perf_header__find_attr(u64 id, struct perf_header *header)
 686 {
 687         int i;
 688
 689         for (i = 0; i < header->attrs; i++) {
 690                 struct perf_header_attr *attr = header->attr[i];
 691                 int j;
 692
 693                 for (j = 0; j < attr->ids; j++) {
 694                         if (attr->id[j] == id)
 695                                 return &attr->attr;
 696                 }
 697         }
 698
 699         return NULL;
 700 }