tools/perf/util/session.c

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