libsanitizer/tsan/tsan_rtl.cc

   1 //===-- tsan_rtl.cc -------------------------------------------------------===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // This file is a part of ThreadSanitizer (TSan), a race detector.
   9 //
  10 // Main file (entry points) for the TSan run-time.
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "sanitizer_common/sanitizer_atomic.h"
  14 #include "sanitizer_common/sanitizer_common.h"
  15 #include "sanitizer_common/sanitizer_libc.h"
  16 #include "sanitizer_common/sanitizer_stackdepot.h"
  17 #include "sanitizer_common/sanitizer_placement_new.h"
  18 #include "sanitizer_common/sanitizer_symbolizer.h"
  19 #include "tsan_defs.h"
  20 #include "tsan_platform.h"
  21 #include "tsan_rtl.h"
  22 #include "tsan_mman.h"
  23 #include "tsan_suppressions.h"
  24 #include "tsan_symbolize.h"
  25
  26 volatile int __tsan_resumed = 0;
  27
  28 extern "C" void __tsan_resume() {
  29   __tsan_resumed = 1;
  30 }
  31
  32 namespace __tsan {
  33
  34 #ifndef TSAN_GO
  35 THREADLOCAL char cur_thread_placeholder[sizeof(ThreadState)] ALIGNED(64);
  36 #endif
  37 static char ctx_placeholder[sizeof(Context)] ALIGNED(64);
  38
  39 // Can be overriden by a front-end.
  40 #ifdef TSAN_EXTERNAL_HOOKS
  41 bool OnFinalize(bool failed);
  42 #else
  43 SANITIZER_INTERFACE_ATTRIBUTE
  44 bool WEAK OnFinalize(bool failed) {
  45   return failed;
  46 }
  47 #endif
  48
  49 static Context *ctx;
  50 Context *CTX() {
  51   return ctx;
  52 }
  53
  54 static char thread_registry_placeholder[sizeof(ThreadRegistry)];
  55
  56 static ThreadContextBase *CreateThreadContext(u32 tid) {
  57   // Map thread trace when context is created.
  58   MapThreadTrace(GetThreadTrace(tid), TraceSize() * sizeof(Event));
  59   MapThreadTrace(GetThreadTraceHeader(tid), sizeof(Trace));
  60   new(ThreadTrace(tid)) Trace();
  61   void *mem = internal_alloc(MBlockThreadContex, sizeof(ThreadContext));
  62   return new(mem) ThreadContext(tid);
  63 }
  64
  65 #ifndef TSAN_GO
  66 static const u32 kThreadQuarantineSize = 16;
  67 #else
  68 static const u32 kThreadQuarantineSize = 64;
  69 #endif
  70
  71 Context::Context()
  72   : initialized()
  73   , report_mtx(MutexTypeReport, StatMtxReport)
  74   , nreported()
  75   , nmissed_expected()
  76   , thread_registry(new(thread_registry_placeholder) ThreadRegistry(
  77       CreateThreadContext, kMaxTid, kThreadQuarantineSize))
  78   , racy_stacks(MBlockRacyStacks)
  79   , racy_addresses(MBlockRacyAddresses)
  80   , fired_suppressions(8) {
  81 }
  82
  83 // The objects are allocated in TLS, so one may rely on zero-initialization.
  84 ThreadState::ThreadState(Context *ctx, int tid, int unique_id, u64 epoch,
  85                          uptr stk_addr, uptr stk_size,
  86                          uptr tls_addr, uptr tls_size)
  87   : fast_state(tid, epoch)
  88   // Do not touch these, rely on zero initialization,
  89   // they may be accessed before the ctor.
  90   // , ignore_reads_and_writes()
  91   // , in_rtl()
  92 #ifndef TSAN_GO
  93   , jmp_bufs(MBlockJmpBuf)
  94 #endif
  95   , tid(tid)
  96   , unique_id(unique_id)
  97   , stk_addr(stk_addr)
  98   , stk_size(stk_size)
  99   , tls_addr(tls_addr)
 100   , tls_size(tls_size) {
 101 }
 102
 103 static void MemoryProfiler(Context *ctx, fd_t fd, int i) {
 104   uptr n_threads;
 105   uptr n_running_threads;
 106   ctx->thread_registry->GetNumberOfThreads(&n_threads, &n_running_threads);
 107   InternalScopedBuffer<char> buf(4096);
 108   internal_snprintf(buf.data(), buf.size(), "%d: nthr=%d nlive=%d\n",
 109       i, n_threads, n_running_threads);
 110   internal_write(fd, buf.data(), internal_strlen(buf.data()));
 111   WriteMemoryProfile(buf.data(), buf.size());
 112   internal_write(fd, buf.data(), internal_strlen(buf.data()));
 113 }
 114
 115 static void BackgroundThread(void *arg) {
 116   ScopedInRtl in_rtl;
 117   Context *ctx = CTX();
 118   const u64 kMs2Ns = 1000 * 1000;
 119
 120   fd_t mprof_fd = kInvalidFd;
 121   if (flags()->profile_memory && flags()->profile_memory[0]) {
 122     InternalScopedBuffer<char> filename(4096);
 123     internal_snprintf(filename.data(), filename.size(), "%s.%d",
 124         flags()->profile_memory, (int)internal_getpid());
 125     uptr openrv = OpenFile(filename.data(), true);
 126     if (internal_iserror(openrv)) {
 127       Printf("ThreadSanitizer: failed to open memory profile file '%s'\n",
 128           &filename[0]);
 129     } else {
 130       mprof_fd = openrv;
 131     }
 132   }
 133
 134   u64 last_flush = NanoTime();
 135   uptr last_rss = 0;
 136   for (int i = 0; ; i++) {
 137     SleepForSeconds(1);
 138     u64 now = NanoTime();
 139
 140     // Flush memory if requested.
 141     if (flags()->flush_memory_ms > 0) {
 142       if (last_flush + flags()->flush_memory_ms * kMs2Ns < now) {
 143         if (flags()->verbosity > 0)
 144           Printf("ThreadSanitizer: periodic memory flush\n");
 145         FlushShadowMemory();
 146         last_flush = NanoTime();
 147       }
 148     }
 149     if (flags()->memory_limit_mb > 0) {
 150       uptr rss = GetRSS();
 151       uptr limit = uptr(flags()->memory_limit_mb) << 20;
 152       if (flags()->verbosity > 0) {
 153         Printf("ThreadSanitizer: memory flush check"
 154                " RSS=%llu LAST=%llu LIMIT=%llu\n",
 155                (u64)rss>>20, (u64)last_rss>>20, (u64)limit>>20);
 156       }
 157       if (2 * rss > limit + last_rss) {
 158         if (flags()->verbosity > 0)
 159           Printf("ThreadSanitizer: flushing memory due to RSS\n");
 160         FlushShadowMemory();
 161         rss = GetRSS();
 162         if (flags()->verbosity > 0)
 163           Printf("ThreadSanitizer: memory flushed RSS=%llu\n", (u64)rss>>20);
 164       }
 165       last_rss = rss;
 166     }
 167
 168     // Write memory profile if requested.
 169     if (mprof_fd != kInvalidFd)
 170       MemoryProfiler(ctx, mprof_fd, i);
 171
 172 #ifndef TSAN_GO
 173     // Flush symbolizer cache if requested.
 174     if (flags()->flush_symbolizer_ms > 0) {
 175       u64 last = atomic_load(&ctx->last_symbolize_time_ns,
 176                              memory_order_relaxed);
 177       if (last != 0 && last + flags()->flush_symbolizer_ms * kMs2Ns < now) {
 178         Lock l(&ctx->report_mtx);
 179         SpinMutexLock l2(&CommonSanitizerReportMutex);
 180         SymbolizeFlush();
 181         atomic_store(&ctx->last_symbolize_time_ns, 0, memory_order_relaxed);
 182       }
 183     }
 184 #endif
 185   }
 186 }
 187
 188 void DontNeedShadowFor(uptr addr, uptr size) {
 189   uptr shadow_beg = MemToShadow(addr);
 190   uptr shadow_end = MemToShadow(addr + size);
 191   FlushUnneededShadowMemory(shadow_beg, shadow_end - shadow_beg);
 192 }
 193
 194 void MapShadow(uptr addr, uptr size) {
 195   MmapFixedNoReserve(MemToShadow(addr), size * kShadowMultiplier);
 196 }
 197
 198 void MapThreadTrace(uptr addr, uptr size) {
 199   DPrintf("#0: Mapping trace at %p-%p(0x%zx)\n", addr, addr + size, size);
 200   CHECK_GE(addr, kTraceMemBegin);
 201   CHECK_LE(addr + size, kTraceMemBegin + kTraceMemSize);
 202   uptr addr1 = (uptr)MmapFixedNoReserve(addr, size);
 203   if (addr1 != addr) {
 204     Printf("FATAL: ThreadSanitizer can not mmap thread trace (%p/%p->%p)\n",
 205         addr, size, addr1);
 206     Die();
 207   }
 208 }
 209
 210 void Initialize(ThreadState *thr) {
 211   // Thread safe because done before all threads exist.
 212   static bool is_initialized = false;
 213   if (is_initialized)
 214     return;
 215   is_initialized = true;
 216   SanitizerToolName = "ThreadSanitizer";
 217   // Install tool-specific callbacks in sanitizer_common.
 218   SetCheckFailedCallback(TsanCheckFailed);
 219
 220   ScopedInRtl in_rtl;
 221 #ifndef TSAN_GO
 222   InitializeAllocator();
 223 #endif
 224   InitializeInterceptors();
 225   const char *env = InitializePlatform();
 226   InitializeMutex();
 227   InitializeDynamicAnnotations();
 228   ctx = new(ctx_placeholder) Context;
 229 #ifndef TSAN_GO
 230   InitializeShadowMemory();
 231 #endif
 232   InitializeFlags(&ctx->flags, env);
 233   // Setup correct file descriptor for error reports.
 234   __sanitizer_set_report_path(flags()->log_path);
 235   InitializeSuppressions();
 236 #ifndef TSAN_GO
 237   InitializeLibIgnore();
 238   // Initialize external symbolizer before internal threads are started.
 239   const char *external_symbolizer = flags()->external_symbolizer_path;
 240   bool external_symbolizer_started =
 241       Symbolizer::Init(external_symbolizer)->IsExternalAvailable();
 242   if (external_symbolizer != 0 && external_symbolizer[0] != '\0' &&
 243       !external_symbolizer_started) {
 244     Printf("Failed to start external symbolizer: '%s'\n",
 245            external_symbolizer);
 246     Die();
 247   }
 248   Symbolizer::Get()->AddHooks(EnterSymbolizer, ExitSymbolizer);
 249 #endif
 250   internal_start_thread(&BackgroundThread, 0);
 251
 252   if (ctx->flags.verbosity)
 253     Printf("***** Running under ThreadSanitizer v2 (pid %d) *****\n",
 254            (int)internal_getpid());
 255
 256   // Initialize thread 0.
 257   int tid = ThreadCreate(thr, 0, 0, true);
 258   CHECK_EQ(tid, 0);
 259   ThreadStart(thr, tid, internal_getpid());
 260   CHECK_EQ(thr->in_rtl, 1);
 261   ctx->initialized = true;
 262
 263   if (flags()->stop_on_start) {
 264     Printf("ThreadSanitizer is suspended at startup (pid %d)."
 265            " Call __tsan_resume().\n",
 266            (int)internal_getpid());
 267     while (__tsan_resumed == 0) {}
 268   }
 269 }
 270
 271 int Finalize(ThreadState *thr) {
 272   ScopedInRtl in_rtl;
 273   Context *ctx = __tsan::ctx;
 274   bool failed = false;
 275
 276   if (flags()->atexit_sleep_ms > 0 && ThreadCount(thr) > 1)
 277     SleepForMillis(flags()->atexit_sleep_ms);
 278
 279   // Wait for pending reports.
 280   ctx->report_mtx.Lock();
 281   CommonSanitizerReportMutex.Lock();
 282   CommonSanitizerReportMutex.Unlock();
 283   ctx->report_mtx.Unlock();
 284
 285 #ifndef TSAN_GO
 286   if (ctx->flags.verbosity)
 287     AllocatorPrintStats();
 288 #endif
 289
 290   ThreadFinalize(thr);
 291
 292   if (ctx->nreported) {
 293     failed = true;
 294 #ifndef TSAN_GO
 295     Printf("ThreadSanitizer: reported %d warnings\n", ctx->nreported);
 296 #else
 297     Printf("Found %d data race(s)\n", ctx->nreported);
 298 #endif
 299   }
 300
 301   if (ctx->nmissed_expected) {
 302     failed = true;
 303     Printf("ThreadSanitizer: missed %d expected races\n",
 304         ctx->nmissed_expected);
 305   }
 306
 307   if (flags()->print_suppressions)
 308     PrintMatchedSuppressions();
 309 #ifndef TSAN_GO
 310   if (flags()->print_benign)
 311     PrintMatchedBenignRaces();
 312 #endif
 313
 314   failed = OnFinalize(failed);
 315
 316   StatAggregate(ctx->stat, thr->stat);
 317   StatOutput(ctx->stat);
 318   return failed ? flags()->exitcode : 0;
 319 }
 320
 321 #ifndef TSAN_GO
 322 u32 CurrentStackId(ThreadState *thr, uptr pc) {
 323   if (thr->shadow_stack_pos == 0)  // May happen during bootstrap.
 324     return 0;
 325   if (pc) {
 326     thr->shadow_stack_pos[0] = pc;
 327     thr->shadow_stack_pos++;
 328   }
 329   u32 id = StackDepotPut(thr->shadow_stack,
 330                          thr->shadow_stack_pos - thr->shadow_stack);
 331   if (pc)
 332     thr->shadow_stack_pos--;
 333   return id;
 334 }
 335 #endif
 336
 337 void TraceSwitch(ThreadState *thr) {
 338   thr->nomalloc++;
 339   ScopedInRtl in_rtl;
 340   Trace *thr_trace = ThreadTrace(thr->tid);
 341   Lock l(&thr_trace->mtx);
 342   unsigned trace = (thr->fast_state.epoch() / kTracePartSize) % TraceParts();
 343   TraceHeader *hdr = &thr_trace->headers[trace];
 344   hdr->epoch0 = thr->fast_state.epoch();
 345   hdr->stack0.ObtainCurrent(thr, 0);
 346   hdr->mset0 = thr->mset;
 347   thr->nomalloc--;
 348 }
 349
 350 Trace *ThreadTrace(int tid) {
 351   return (Trace*)GetThreadTraceHeader(tid);
 352 }
 353
 354 uptr TraceTopPC(ThreadState *thr) {
 355   Event *events = (Event*)GetThreadTrace(thr->tid);
 356   uptr pc = events[thr->fast_state.GetTracePos()];
 357   return pc;
 358 }
 359
 360 uptr TraceSize() {
 361   return (uptr)(1ull << (kTracePartSizeBits + flags()->history_size + 1));
 362 }
 363
 364 uptr TraceParts() {
 365   return TraceSize() / kTracePartSize;
 366 }
 367
 368 #ifndef TSAN_GO
 369 extern "C" void __tsan_trace_switch() {
 370   TraceSwitch(cur_thread());
 371 }
 372
 373 extern "C" void __tsan_report_race() {
 374   ReportRace(cur_thread());
 375 }
 376 #endif
 377
 378 ALWAYS_INLINE
 379 Shadow LoadShadow(u64 *p) {
 380   u64 raw = atomic_load((atomic_uint64_t*)p, memory_order_relaxed);
 381   return Shadow(raw);
 382 }
 383
 384 ALWAYS_INLINE
 385 void StoreShadow(u64 *sp, u64 s) {
 386   atomic_store((atomic_uint64_t*)sp, s, memory_order_relaxed);
 387 }
 388
 389 ALWAYS_INLINE
 390 void StoreIfNotYetStored(u64 *sp, u64 *s) {
 391   StoreShadow(sp, *s);
 392   *s = 0;
 393 }
 394
 395 static inline void HandleRace(ThreadState *thr, u64 *shadow_mem,
 396                               Shadow cur, Shadow old) {
 397   thr->racy_state[0] = cur.raw();
 398   thr->racy_state[1] = old.raw();
 399   thr->racy_shadow_addr = shadow_mem;
 400 #ifndef TSAN_GO
 401   HACKY_CALL(__tsan_report_race);
 402 #else
 403   ReportRace(thr);
 404 #endif
 405 }
 406
 407 static inline bool OldIsInSameSynchEpoch(Shadow old, ThreadState *thr) {
 408   return old.epoch() >= thr->fast_synch_epoch;
 409 }
 410
 411 static inline bool HappensBefore(Shadow old, ThreadState *thr) {
 412   return thr->clock.get(old.TidWithIgnore()) >= old.epoch();
 413 }
 414
 415 ALWAYS_INLINE USED
 416 void MemoryAccessImpl(ThreadState *thr, uptr addr,
 417     int kAccessSizeLog, bool kAccessIsWrite, bool kIsAtomic,
 418     u64 *shadow_mem, Shadow cur) {
 419   StatInc(thr, StatMop);
 420   StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead);
 421   StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog));
 422
 423   // This potentially can live in an MMX/SSE scratch register.
 424   // The required intrinsics are:
 425   // __m128i _mm_move_epi64(__m128i*);
 426   // _mm_storel_epi64(u64*, __m128i);
 427   u64 store_word = cur.raw();
 428
 429   // scan all the shadow values and dispatch to 4 categories:
 430   // same, replace, candidate and race (see comments below).
 431   // we consider only 3 cases regarding access sizes:
 432   // equal, intersect and not intersect. initially I considered
 433   // larger and smaller as well, it allowed to replace some
 434   // 'candidates' with 'same' or 'replace', but I think
 435   // it's just not worth it (performance- and complexity-wise).
 436
 437   Shadow old(0);
 438   if (kShadowCnt == 1) {
 439     int idx = 0;
 440 #include "tsan_update_shadow_word_inl.h"
 441   } else if (kShadowCnt == 2) {
 442     int idx = 0;
 443 #include "tsan_update_shadow_word_inl.h"
 444     idx = 1;
 445 #include "tsan_update_shadow_word_inl.h"
 446   } else if (kShadowCnt == 4) {
 447     int idx = 0;
 448 #include "tsan_update_shadow_word_inl.h"
 449     idx = 1;
 450 #include "tsan_update_shadow_word_inl.h"
 451     idx = 2;
 452 #include "tsan_update_shadow_word_inl.h"
 453     idx = 3;
 454 #include "tsan_update_shadow_word_inl.h"
 455   } else if (kShadowCnt == 8) {
 456     int idx = 0;
 457 #include "tsan_update_shadow_word_inl.h"
 458     idx = 1;
 459 #include "tsan_update_shadow_word_inl.h"
 460     idx = 2;
 461 #include "tsan_update_shadow_word_inl.h"
 462     idx = 3;
 463 #include "tsan_update_shadow_word_inl.h"
 464     idx = 4;
 465 #include "tsan_update_shadow_word_inl.h"
 466     idx = 5;
 467 #include "tsan_update_shadow_word_inl.h"
 468     idx = 6;
 469 #include "tsan_update_shadow_word_inl.h"
 470     idx = 7;
 471 #include "tsan_update_shadow_word_inl.h"
 472   } else {
 473     CHECK(false);
 474   }
 475
 476   // we did not find any races and had already stored
 477   // the current access info, so we are done
 478   if (LIKELY(store_word == 0))
 479     return;
 480   // choose a random candidate slot and replace it
 481   StoreShadow(shadow_mem + (cur.epoch() % kShadowCnt), store_word);
 482   StatInc(thr, StatShadowReplace);
 483   return;
 484  RACE:
 485   HandleRace(thr, shadow_mem, cur, old);
 486   return;
 487 }
 488
 489 void UnalignedMemoryAccess(ThreadState *thr, uptr pc, uptr addr,
 490     int size, bool kAccessIsWrite, bool kIsAtomic) {
 491   while (size) {
 492     int size1 = 1;
 493     int kAccessSizeLog = kSizeLog1;
 494     if (size >= 8 && (addr & ~7) == ((addr + 8) & ~7)) {
 495       size1 = 8;
 496       kAccessSizeLog = kSizeLog8;
 497     } else if (size >= 4 && (addr & ~7) == ((addr + 4) & ~7)) {
 498       size1 = 4;
 499       kAccessSizeLog = kSizeLog4;
 500     } else if (size >= 2 && (addr & ~7) == ((addr + 2) & ~7)) {
 501       size1 = 2;
 502       kAccessSizeLog = kSizeLog2;
 503     }
 504     MemoryAccess(thr, pc, addr, kAccessSizeLog, kAccessIsWrite, kIsAtomic);
 505     addr += size1;
 506     size -= size1;
 507   }
 508 }
 509
 510 ALWAYS_INLINE USED
 511 void MemoryAccess(ThreadState *thr, uptr pc, uptr addr,
 512     int kAccessSizeLog, bool kAccessIsWrite, bool kIsAtomic) {
 513   u64 *shadow_mem = (u64*)MemToShadow(addr);
 514   DPrintf2("#%d: MemoryAccess: @%p %p size=%d"
 515       " is_write=%d shadow_mem=%p {%zx, %zx, %zx, %zx}\n",
 516       (int)thr->fast_state.tid(), (void*)pc, (void*)addr,
 517       (int)(1 << kAccessSizeLog), kAccessIsWrite, shadow_mem,
 518       (uptr)shadow_mem[0], (uptr)shadow_mem[1],
 519       (uptr)shadow_mem[2], (uptr)shadow_mem[3]);
 520 #if TSAN_DEBUG
 521   if (!IsAppMem(addr)) {
 522     Printf("Access to non app mem %zx\n", addr);
 523     DCHECK(IsAppMem(addr));
 524   }
 525   if (!IsShadowMem((uptr)shadow_mem)) {
 526     Printf("Bad shadow addr %p (%zx)\n", shadow_mem, addr);
 527     DCHECK(IsShadowMem((uptr)shadow_mem));
 528   }
 529 #endif
 530
 531   if (*shadow_mem == kShadowRodata) {
 532     // Access to .rodata section, no races here.
 533     // Measurements show that it can be 10-20% of all memory accesses.
 534     StatInc(thr, StatMop);
 535     StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead);
 536     StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog));
 537     StatInc(thr, StatMopRodata);
 538     return;
 539   }
 540
 541   FastState fast_state = thr->fast_state;
 542   if (fast_state.GetIgnoreBit())
 543     return;
 544   fast_state.IncrementEpoch();
 545   thr->fast_state = fast_state;
 546   Shadow cur(fast_state);
 547   cur.SetAddr0AndSizeLog(addr & 7, kAccessSizeLog);
 548   cur.SetWrite(kAccessIsWrite);
 549   cur.SetAtomic(kIsAtomic);
 550
 551   // We must not store to the trace if we do not store to the shadow.
 552   // That is, this call must be moved somewhere below.
 553   TraceAddEvent(thr, fast_state, EventTypeMop, pc);
 554
 555   MemoryAccessImpl(thr, addr, kAccessSizeLog, kAccessIsWrite, kIsAtomic,
 556       shadow_mem, cur);
 557 }
 558
 559 static void MemoryRangeSet(ThreadState *thr, uptr pc, uptr addr, uptr size,
 560                            u64 val) {
 561   (void)thr;
 562   (void)pc;
 563   if (size == 0)
 564     return;
 565   // FIXME: fix me.
 566   uptr offset = addr % kShadowCell;
 567   if (offset) {
 568     offset = kShadowCell - offset;
 569     if (size <= offset)
 570       return;
 571     addr += offset;
 572     size -= offset;
 573   }
 574   DCHECK_EQ(addr % 8, 0);
 575   // If a user passes some insane arguments (memset(0)),
 576   // let it just crash as usual.
 577   if (!IsAppMem(addr) || !IsAppMem(addr + size - 1))
 578     return;
 579   // Don't want to touch lots of shadow memory.
 580   // If a program maps 10MB stack, there is no need reset the whole range.
 581   size = (size + (kShadowCell - 1)) & ~(kShadowCell - 1);
 582   // UnmapOrDie/MmapFixedNoReserve does not work on Windows,
 583   // so we do it only for C/C++.
 584   if (kGoMode || size < 64*1024) {
 585     u64 *p = (u64*)MemToShadow(addr);
 586     CHECK(IsShadowMem((uptr)p));
 587     CHECK(IsShadowMem((uptr)(p + size * kShadowCnt / kShadowCell - 1)));
 588     // FIXME: may overwrite a part outside the region
 589     for (uptr i = 0; i < size / kShadowCell * kShadowCnt;) {
 590       p[i++] = val;
 591       for (uptr j = 1; j < kShadowCnt; j++)
 592         p[i++] = 0;
 593     }
 594   } else {
 595     // The region is big, reset only beginning and end.
 596     const uptr kPageSize = 4096;
 597     u64 *begin = (u64*)MemToShadow(addr);
 598     u64 *end = begin + size / kShadowCell * kShadowCnt;
 599     u64 *p = begin;
 600     // Set at least first kPageSize/2 to page boundary.
 601     while ((p < begin + kPageSize / kShadowSize / 2) || ((uptr)p % kPageSize)) {
 602       *p++ = val;
 603       for (uptr j = 1; j < kShadowCnt; j++)
 604         *p++ = 0;
 605     }
 606     // Reset middle part.
 607     u64 *p1 = p;
 608     p = RoundDown(end, kPageSize);
 609     UnmapOrDie((void*)p1, (uptr)p - (uptr)p1);
 610     MmapFixedNoReserve((uptr)p1, (uptr)p - (uptr)p1);
 611     // Set the ending.
 612     while (p < end) {
 613       *p++ = val;
 614       for (uptr j = 1; j < kShadowCnt; j++)
 615         *p++ = 0;
 616     }
 617   }
 618 }
 619
 620 void MemoryResetRange(ThreadState *thr, uptr pc, uptr addr, uptr size) {
 621   MemoryRangeSet(thr, pc, addr, size, 0);
 622 }
 623
 624 void MemoryRangeFreed(ThreadState *thr, uptr pc, uptr addr, uptr size) {
 625   // Processing more than 1k (4k of shadow) is expensive,
 626   // can cause excessive memory consumption (user does not necessary touch
 627   // the whole range) and most likely unnecessary.
 628   if (size > 1024)
 629     size = 1024;
 630   CHECK_EQ(thr->is_freeing, false);
 631   thr->is_freeing = true;
 632   MemoryAccessRange(thr, pc, addr, size, true);
 633   thr->is_freeing = false;
 634   thr->fast_state.IncrementEpoch();
 635   TraceAddEvent(thr, thr->fast_state, EventTypeMop, pc);
 636   Shadow s(thr->fast_state);
 637   s.ClearIgnoreBit();
 638   s.MarkAsFreed();
 639   s.SetWrite(true);
 640   s.SetAddr0AndSizeLog(0, 3);
 641   MemoryRangeSet(thr, pc, addr, size, s.raw());
 642 }
 643
 644 void MemoryRangeImitateWrite(ThreadState *thr, uptr pc, uptr addr, uptr size) {
 645   thr->fast_state.IncrementEpoch();
 646   TraceAddEvent(thr, thr->fast_state, EventTypeMop, pc);
 647   Shadow s(thr->fast_state);
 648   s.ClearIgnoreBit();
 649   s.SetWrite(true);
 650   s.SetAddr0AndSizeLog(0, 3);
 651   MemoryRangeSet(thr, pc, addr, size, s.raw());
 652 }
 653
 654 ALWAYS_INLINE USED
 655 void FuncEntry(ThreadState *thr, uptr pc) {
 656   DCHECK_EQ(thr->in_rtl, 0);
 657   StatInc(thr, StatFuncEnter);
 658   DPrintf2("#%d: FuncEntry %p\n", (int)thr->fast_state.tid(), (void*)pc);
 659   thr->fast_state.IncrementEpoch();
 660   TraceAddEvent(thr, thr->fast_state, EventTypeFuncEnter, pc);
 661
 662   // Shadow stack maintenance can be replaced with
 663   // stack unwinding during trace switch (which presumably must be faster).
 664   DCHECK_GE(thr->shadow_stack_pos, thr->shadow_stack);
 665 #ifndef TSAN_GO
 666   DCHECK_LT(thr->shadow_stack_pos, thr->shadow_stack_end);
 667 #else
 668   if (thr->shadow_stack_pos == thr->shadow_stack_end) {
 669     const int sz = thr->shadow_stack_end - thr->shadow_stack;
 670     const int newsz = 2 * sz;
 671     uptr *newstack = (uptr*)internal_alloc(MBlockShadowStack,
 672         newsz * sizeof(uptr));
 673     internal_memcpy(newstack, thr->shadow_stack, sz * sizeof(uptr));
 674     internal_free(thr->shadow_stack);
 675     thr->shadow_stack = newstack;
 676     thr->shadow_stack_pos = newstack + sz;
 677     thr->shadow_stack_end = newstack + newsz;
 678   }
 679 #endif
 680   thr->shadow_stack_pos[0] = pc;
 681   thr->shadow_stack_pos++;
 682 }
 683
 684 ALWAYS_INLINE USED
 685 void FuncExit(ThreadState *thr) {
 686   DCHECK_EQ(thr->in_rtl, 0);
 687   StatInc(thr, StatFuncExit);
 688   DPrintf2("#%d: FuncExit\n", (int)thr->fast_state.tid());
 689   thr->fast_state.IncrementEpoch();
 690   TraceAddEvent(thr, thr->fast_state, EventTypeFuncExit, 0);
 691
 692   DCHECK_GT(thr->shadow_stack_pos, thr->shadow_stack);
 693 #ifndef TSAN_GO
 694   DCHECK_LT(thr->shadow_stack_pos, thr->shadow_stack_end);
 695 #endif
 696   thr->shadow_stack_pos--;
 697 }
 698
 699 void ThreadIgnoreBegin(ThreadState *thr, uptr pc) {
 700   DPrintf("#%d: ThreadIgnoreBegin\n", thr->tid);
 701   thr->ignore_reads_and_writes++;
 702   CHECK_GT(thr->ignore_reads_and_writes, 0);
 703   thr->fast_state.SetIgnoreBit();
 704 #ifndef TSAN_GO
 705   thr->mop_ignore_set.Add(CurrentStackId(thr, pc));
 706 #endif
 707 }
 708
 709 void ThreadIgnoreEnd(ThreadState *thr, uptr pc) {
 710   DPrintf("#%d: ThreadIgnoreEnd\n", thr->tid);
 711   thr->ignore_reads_and_writes--;
 712   CHECK_GE(thr->ignore_reads_and_writes, 0);
 713   if (thr->ignore_reads_and_writes == 0) {
 714     thr->fast_state.ClearIgnoreBit();
 715 #ifndef TSAN_GO
 716     thr->mop_ignore_set.Reset();
 717 #endif
 718   }
 719 }
 720
 721 void ThreadIgnoreSyncBegin(ThreadState *thr, uptr pc) {
 722   DPrintf("#%d: ThreadIgnoreSyncBegin\n", thr->tid);
 723   thr->ignore_sync++;
 724   CHECK_GT(thr->ignore_sync, 0);
 725 #ifndef TSAN_GO
 726   thr->sync_ignore_set.Add(CurrentStackId(thr, pc));
 727 #endif
 728 }
 729
 730 void ThreadIgnoreSyncEnd(ThreadState *thr, uptr pc) {
 731   DPrintf("#%d: ThreadIgnoreSyncEnd\n", thr->tid);
 732   thr->ignore_sync--;
 733   CHECK_GE(thr->ignore_sync, 0);
 734 #ifndef TSAN_GO
 735   if (thr->ignore_sync == 0)
 736     thr->mop_ignore_set.Reset();
 737 #endif
 738 }
 739
 740 bool MD5Hash::operator==(const MD5Hash &other) const {
 741   return hash[0] == other.hash[0] && hash[1] == other.hash[1];
 742 }
 743
 744 #if TSAN_DEBUG
 745 void build_consistency_debug() {}
 746 #else
 747 void build_consistency_release() {}
 748 #endif
 749
 750 #if TSAN_COLLECT_STATS
 751 void build_consistency_stats() {}
 752 #else
 753 void build_consistency_nostats() {}
 754 #endif
 755
 756 #if TSAN_SHADOW_COUNT == 1
 757 void build_consistency_shadow1() {}
 758 #elif TSAN_SHADOW_COUNT == 2
 759 void build_consistency_shadow2() {}
 760 #elif TSAN_SHADOW_COUNT == 4
 761 void build_consistency_shadow4() {}
 762 #else
 763 void build_consistency_shadow8() {}
 764 #endif
 765
 766 }  // namespace __tsan
 767
 768 #ifndef TSAN_GO
 769 // Must be included in this file to make sure everything is inlined.
 770 #include "tsan_interface_inl.h"
 771 #endif