1 files changed, 195 insertions, 265 deletions

diff --git a/libsanitizer/tsan/tsan_rtl_thread.cc b/libsanitizer/tsan/tsan_rtl_thread.cc
index e30916dc627..9811e1c015f 100644
--- a/libsanitizer/tsan/tsan_rtl_thread.cc
+++ b/libsanitizer/tsan/tsan_rtl_thread.cc
@@ -18,144 +18,193 @@
 
 namespace __tsan {
 
+// ThreadContext implementation.
+
+ThreadContext::ThreadContext(int tid)
+  : ThreadContextBase(tid)
+  , thr()
+  , sync()
+  , epoch0()
+  , epoch1() {
+}
+
 #ifndef TSAN_GO
-const int kThreadQuarantineSize = 16;
-#else
-const int kThreadQuarantineSize = 64;
+ThreadContext::~ThreadContext() {
+}
 #endif
 
-static void MaybeReportThreadLeak(ThreadContext *tctx) {
-  if (tctx->detached)
+void ThreadContext::OnDead() {
+  sync.Reset();
+}
+
+void ThreadContext::OnJoined(void *arg) {
+  ThreadState *caller_thr = static_cast<ThreadState *>(arg);
+  caller_thr->clock.acquire(&sync);
+  StatInc(caller_thr, StatSyncAcquire);
+  sync.Reset();
+}
+
+struct OnCreatedArgs {
+  ThreadState *thr;
+  uptr pc;
+};
+
+void ThreadContext::OnCreated(void *arg) {
+  thr = 0;
+  if (tid == 0)
     return;
-  if (tctx->status != ThreadStatusCreated
-      && tctx->status != ThreadStatusRunning
-      && tctx->status != ThreadStatusFinished)
+  OnCreatedArgs *args = static_cast<OnCreatedArgs *>(arg);
+  args->thr->fast_state.IncrementEpoch();
+  // Can't increment epoch w/o writing to the trace as well.
+  TraceAddEvent(args->thr, args->thr->fast_state, EventTypeMop, 0);
+  args->thr->clock.set(args->thr->tid, args->thr->fast_state.epoch());
+  args->thr->fast_synch_epoch = args->thr->fast_state.epoch();
+  args->thr->clock.release(&sync);
+  StatInc(args->thr, StatSyncRelease);
+#ifdef TSAN_GO
+  creation_stack.ObtainCurrent(args->thr, args->pc);
+#else
+  creation_stack_id = CurrentStackId(args->thr, args->pc);
+#endif
+  if (reuse_count == 0)
+    StatInc(args->thr, StatThreadMaxTid);
+}
+
+void ThreadContext::OnReset() {
+  sync.Reset();
+  FlushUnneededShadowMemory(GetThreadTrace(tid), TraceSize() * sizeof(Event));
+  //!!! FlushUnneededShadowMemory(GetThreadTraceHeader(tid), sizeof(Trace));
+}
+
+struct OnStartedArgs {
+  ThreadState *thr;
+  uptr stk_addr;
+  uptr stk_size;
+  uptr tls_addr;
+  uptr tls_size;
+};
+
+void ThreadContext::OnStarted(void *arg) {
+  OnStartedArgs *args = static_cast<OnStartedArgs*>(arg);
+  thr = args->thr;
+  // RoundUp so that one trace part does not contain events
+  // from different threads.
+  epoch0 = RoundUp(epoch1 + 1, kTracePartSize);
+  epoch1 = (u64)-1;
+  new(thr) ThreadState(CTX(), tid, unique_id,
+      epoch0, args->stk_addr, args->stk_size, args->tls_addr, args->tls_size);
+#ifdef TSAN_GO
+  // Setup dynamic shadow stack.
+  const int kInitStackSize = 8;
+  args->thr->shadow_stack = (uptr*)internal_alloc(MBlockShadowStack,
+      kInitStackSize * sizeof(uptr));
+  args->thr->shadow_stack_pos = thr->shadow_stack;
+  args->thr->shadow_stack_end = thr->shadow_stack + kInitStackSize;
+#endif
+#ifndef TSAN_GO
+  AllocatorThreadStart(args->thr);
+#endif
+  thr = args->thr;
+  thr->fast_synch_epoch = epoch0;
+  thr->clock.set(tid, epoch0);
+  thr->clock.acquire(&sync);
+  thr->fast_state.SetHistorySize(flags()->history_size);
+  const uptr trace = (epoch0 / kTracePartSize) % TraceParts();
+  Trace *thr_trace = ThreadTrace(thr->tid);
+  thr_trace->headers[trace].epoch0 = epoch0;
+  StatInc(thr, StatSyncAcquire);
+  sync.Reset();
+  DPrintf("#%d: ThreadStart epoch=%zu stk_addr=%zx stk_size=%zx "
+          "tls_addr=%zx tls_size=%zx\n",
+          tid, (uptr)epoch0, args->stk_addr, args->stk_size,
+          args->tls_addr, args->tls_size);
+  thr->is_alive = true;
+}
+
+void ThreadContext::OnFinished() {
+  if (!detached) {
+    thr->fast_state.IncrementEpoch();
+    // Can't increment epoch w/o writing to the trace as well.
+    TraceAddEvent(thr, thr->fast_state, EventTypeMop, 0);
+    thr->clock.set(thr->tid, thr->fast_state.epoch());
+    thr->fast_synch_epoch = thr->fast_state.epoch();
+    thr->clock.release(&sync);
+    StatInc(thr, StatSyncRelease);
+  }
+  epoch1 = thr->fast_state.epoch();
+
+#ifndef TSAN_GO
+  AllocatorThreadFinish(thr);
+#endif
+  thr->~ThreadState();
+  StatAggregate(CTX()->stat, thr->stat);
+  thr = 0;
+}
+
+#ifndef TSAN_GO
+struct ThreadLeak {
+  ThreadContext *tctx;
+  int count;
+};
+
+static void MaybeReportThreadLeak(ThreadContextBase *tctx_base, void *arg) {
+  Vector<ThreadLeak> &leaks = *(Vector<ThreadLeak>*)arg;
+  ThreadContext *tctx = static_cast<ThreadContext*>(tctx_base);
+  if (tctx->detached || tctx->status != ThreadStatusFinished)
     return;
-  ScopedReport rep(ReportTypeThreadLeak);
-  rep.AddThread(tctx);
-  OutputReport(CTX(), rep);
+  for (uptr i = 0; i < leaks.Size(); i++) {
+    if (leaks[i].tctx->creation_stack_id == tctx->creation_stack_id) {
+      leaks[i].count++;
+      return;
+    }
+  }
+  ThreadLeak leak = {tctx, 1};
+  leaks.PushBack(leak);
+}
+#endif
+
+static void ThreadCheckIgnore(ThreadState *thr) {
+  if (thr->ignore_reads_and_writes) {
+    Printf("ThreadSanitizer: thread T%d finished with ignores enabled.\n",
+           thr->tid);
+  }
 }
 
 void ThreadFinalize(ThreadState *thr) {
   CHECK_GT(thr->in_rtl, 0);
+  ThreadCheckIgnore(thr);
+#ifndef TSAN_GO
   if (!flags()->report_thread_leaks)
     return;
-  Context *ctx = CTX();
-  Lock l(&ctx->thread_mtx);
-  for (unsigned i = 0; i < kMaxTid; i++) {
-    ThreadContext *tctx = ctx->threads[i];
-    if (tctx == 0)
-      continue;
-    MaybeReportThreadLeak(tctx);
+  ThreadRegistryLock l(CTX()->thread_registry);
+  Vector<ThreadLeak> leaks(MBlockScopedBuf);
+  CTX()->thread_registry->RunCallbackForEachThreadLocked(
+      MaybeReportThreadLeak, &leaks);
+  for (uptr i = 0; i < leaks.Size(); i++) {
+    ScopedReport rep(ReportTypeThreadLeak);
+    rep.AddThread(leaks[i].tctx);
+    rep.SetCount(leaks[i].count);
+    OutputReport(CTX(), rep);
   }
+#endif
 }
 
 int ThreadCount(ThreadState *thr) {
   CHECK_GT(thr->in_rtl, 0);
   Context *ctx = CTX();
-  Lock l(&ctx->thread_mtx);
-  int cnt = 0;
-  for (unsigned i = 0; i < kMaxTid; i++) {
-    ThreadContext *tctx = ctx->threads[i];
-    if (tctx == 0)
-      continue;
-    if (tctx->status != ThreadStatusCreated
-        && tctx->status != ThreadStatusRunning)
-      continue;
-    cnt++;
-  }
-  return cnt;
-}
-
-static void ThreadDead(ThreadState *thr, ThreadContext *tctx) {
-  Context *ctx = CTX();
-  CHECK_GT(thr->in_rtl, 0);
-  CHECK(tctx->status == ThreadStatusRunning
-      || tctx->status == ThreadStatusFinished);
-  DPrintf("#%d: ThreadDead uid=%zu\n", thr->tid, tctx->user_id);
-  tctx->status = ThreadStatusDead;
-  tctx->user_id = 0;
-  tctx->sync.Reset();
-
-  // Put to dead list.
-  tctx->dead_next = 0;
-  if (ctx->dead_list_size == 0)
-    ctx->dead_list_head = tctx;
-  else
-    ctx->dead_list_tail->dead_next = tctx;
-  ctx->dead_list_tail = tctx;
-  ctx->dead_list_size++;
+  uptr result;
+  ctx->thread_registry->GetNumberOfThreads(0, 0, &result);
+  return (int)result;
 }
 
 int ThreadCreate(ThreadState *thr, uptr pc, uptr uid, bool detached) {
   CHECK_GT(thr->in_rtl, 0);
-  Context *ctx = CTX();
-  Lock l(&ctx->thread_mtx);
   StatInc(thr, StatThreadCreate);
-  int tid = -1;
-  ThreadContext *tctx = 0;
-  if (ctx->dead_list_size > kThreadQuarantineSize
-      || ctx->thread_seq >= kMaxTid) {
-    // Reusing old thread descriptor and tid.
-    if (ctx->dead_list_size == 0) {
-      Printf("ThreadSanitizer: %d thread limit exceeded. Dying.\n",
-                 kMaxTid);
-      Die();
-    }
-    StatInc(thr, StatThreadReuse);
-    tctx = ctx->dead_list_head;
-    ctx->dead_list_head = tctx->dead_next;
-    ctx->dead_list_size--;
-    if (ctx->dead_list_size == 0) {
-      CHECK_EQ(tctx->dead_next, 0);
-      ctx->dead_list_head = 0;
-    }
-    CHECK_EQ(tctx->status, ThreadStatusDead);
-    tctx->status = ThreadStatusInvalid;
-    tctx->reuse_count++;
-    tctx->sync.Reset();
-    tid = tctx->tid;
-    DestroyAndFree(tctx->dead_info);
-    if (tctx->name) {
-      internal_free(tctx->name);
-      tctx->name = 0;
-    }
-  } else {
-    // Allocating new thread descriptor and tid.
-    StatInc(thr, StatThreadMaxTid);
-    tid = ctx->thread_seq++;
-    void *mem = internal_alloc(MBlockThreadContex, sizeof(ThreadContext));
-    tctx = new(mem) ThreadContext(tid);
-    ctx->threads[tid] = tctx;
-    MapThreadTrace(GetThreadTrace(tid), TraceSize() * sizeof(Event));
-  }
-  CHECK_NE(tctx, 0);
-  CHECK_GE(tid, 0);
-  CHECK_LT(tid, kMaxTid);
+  Context *ctx = CTX();
+  OnCreatedArgs args = { thr, pc };
+  int tid = ctx->thread_registry->CreateThread(uid, detached, thr->tid, &args);
   DPrintf("#%d: ThreadCreate tid=%d uid=%zu\n", thr->tid, tid, uid);
-  CHECK_EQ(tctx->status, ThreadStatusInvalid);
-  ctx->alive_threads++;
-  if (ctx->max_alive_threads < ctx->alive_threads) {
-    ctx->max_alive_threads++;
-    CHECK_EQ(ctx->max_alive_threads, ctx->alive_threads);
-    StatInc(thr, StatThreadMaxAlive);
-  }
-  tctx->status = ThreadStatusCreated;
-  tctx->thr = 0;
-  tctx->user_id = uid;
-  tctx->unique_id = ctx->unique_thread_seq++;
-  tctx->detached = detached;
-  if (tid) {
-    thr->fast_state.IncrementEpoch();
-    // Can't increment epoch w/o writing to the trace as well.
-    TraceAddEvent(thr, thr->fast_state, EventTypeMop, 0);
-    thr->clock.set(thr->tid, thr->fast_state.epoch());
-    thr->fast_synch_epoch = thr->fast_state.epoch();
-    thr->clock.release(&tctx->sync);
-    StatInc(thr, StatSyncRelease);
-    tctx->creation_stack.ObtainCurrent(thr, pc);
-    tctx->creation_tid = thr->tid;
-  }
+  StatSet(thr, StatThreadMaxAlive, ctx->thread_registry->GetMaxAliveThreads());
   return tid;
 }
 
@@ -168,9 +217,8 @@ void ThreadStart(ThreadState *thr, int tid, uptr os_id) {
   GetThreadStackAndTls(tid == 0, &stk_addr, &stk_size, &tls_addr, &tls_size);
 
   if (tid) {
-    if (stk_addr && stk_size) {
-      MemoryResetRange(thr, /*pc=*/ 1, stk_addr, stk_size);
-    }
+    if (stk_addr && stk_size)
+      MemoryRangeImitateWrite(thr, /*pc=*/ 1, stk_addr, stk_size);
 
     if (tls_addr && tls_size) {
       // Check that the thr object is in tls;
@@ -181,116 +229,42 @@ void ThreadStart(ThreadState *thr, int tid, uptr os_id) {
       CHECK_GE(thr_end, tls_addr);
       CHECK_LE(thr_end, tls_addr + tls_size);
       // Since the thr object is huge, skip it.
-      MemoryResetRange(thr, /*pc=*/ 2, tls_addr, thr_beg - tls_addr);
-      MemoryResetRange(thr, /*pc=*/ 2, thr_end, tls_addr + tls_size - thr_end);
+      MemoryRangeImitateWrite(thr, /*pc=*/ 2, tls_addr, thr_beg - tls_addr);
+      MemoryRangeImitateWrite(thr, /*pc=*/ 2,
+          thr_end, tls_addr + tls_size - thr_end);
     }
   }
 
-  Lock l(&CTX()->thread_mtx);
-  ThreadContext *tctx = CTX()->threads[tid];
-  CHECK_NE(tctx, 0);
-  CHECK_EQ(tctx->status, ThreadStatusCreated);
-  tctx->status = ThreadStatusRunning;
-  tctx->os_id = os_id;
-  // RoundUp so that one trace part does not contain events
-  // from different threads.
-  tctx->epoch0 = RoundUp(tctx->epoch1 + 1, kTracePartSize);
-  tctx->epoch1 = (u64)-1;
-  new(thr) ThreadState(CTX(), tid, tctx->unique_id,
-      tctx->epoch0, stk_addr, stk_size,
-      tls_addr, tls_size);
-#ifdef TSAN_GO
-  // Setup dynamic shadow stack.
-  const int kInitStackSize = 8;
-  thr->shadow_stack = (uptr*)internal_alloc(MBlockShadowStack,
-      kInitStackSize * sizeof(uptr));
-  thr->shadow_stack_pos = thr->shadow_stack;
-  thr->shadow_stack_end = thr->shadow_stack + kInitStackSize;
-#endif
-#ifndef TSAN_GO
-  AllocatorThreadStart(thr);
-#endif
-  tctx->thr = thr;
-  thr->fast_synch_epoch = tctx->epoch0;
-  thr->clock.set(tid, tctx->epoch0);
-  thr->clock.acquire(&tctx->sync);
-  thr->fast_state.SetHistorySize(flags()->history_size);
-  const uptr trace = (tctx->epoch0 / kTracePartSize) % TraceParts();
-  thr->trace.headers[trace].epoch0 = tctx->epoch0;
-  StatInc(thr, StatSyncAcquire);
-  DPrintf("#%d: ThreadStart epoch=%zu stk_addr=%zx stk_size=%zx "
-          "tls_addr=%zx tls_size=%zx\n",
-          tid, (uptr)tctx->epoch0, stk_addr, stk_size, tls_addr, tls_size);
-  thr->is_alive = true;
+  OnStartedArgs args = { thr, stk_addr, stk_size, tls_addr, tls_size };
+  CTX()->thread_registry->StartThread(tid, os_id, &args);
 }
 
 void ThreadFinish(ThreadState *thr) {
   CHECK_GT(thr->in_rtl, 0);
+  ThreadCheckIgnore(thr);
   StatInc(thr, StatThreadFinish);
-  // FIXME: Treat it as write.
   if (thr->stk_addr && thr->stk_size)
-    MemoryResetRange(thr, /*pc=*/ 3, thr->stk_addr, thr->stk_size);
-  if (thr->tls_addr && thr->tls_size) {
-    const uptr thr_beg = (uptr)thr;
-    const uptr thr_end = (uptr)thr + sizeof(*thr);
-    // Since the thr object is huge, skip it.
-    MemoryResetRange(thr, /*pc=*/ 4, thr->tls_addr, thr_beg - thr->tls_addr);
-    MemoryResetRange(thr, /*pc=*/ 5,
-        thr_end, thr->tls_addr + thr->tls_size - thr_end);
-  }
+    DontNeedShadowFor(thr->stk_addr, thr->stk_size);
+  if (thr->tls_addr && thr->tls_size)
+    DontNeedShadowFor(thr->tls_addr, thr->tls_size);
   thr->is_alive = false;
   Context *ctx = CTX();
-  Lock l(&ctx->thread_mtx);
-  ThreadContext *tctx = ctx->threads[thr->tid];
-  CHECK_NE(tctx, 0);
-  CHECK_EQ(tctx->status, ThreadStatusRunning);
-  CHECK_GT(ctx->alive_threads, 0);
-  ctx->alive_threads--;
-  if (tctx->detached) {
-    ThreadDead(thr, tctx);
-  } else {
-    thr->fast_state.IncrementEpoch();
-    // Can't increment epoch w/o writing to the trace as well.
-    TraceAddEvent(thr, thr->fast_state, EventTypeMop, 0);
-    thr->clock.set(thr->tid, thr->fast_state.epoch());
-    thr->fast_synch_epoch = thr->fast_state.epoch();
-    thr->clock.release(&tctx->sync);
-    StatInc(thr, StatSyncRelease);
-    tctx->status = ThreadStatusFinished;
-  }
+  ctx->thread_registry->FinishThread(thr->tid);
+}
 
-  // Save from info about the thread.
-  tctx->dead_info = new(internal_alloc(MBlockDeadInfo, sizeof(ThreadDeadInfo)))
-      ThreadDeadInfo();
-  for (uptr i = 0; i < TraceParts(); i++) {
-    tctx->dead_info->trace.headers[i].epoch0 = thr->trace.headers[i].epoch0;
-    tctx->dead_info->trace.headers[i].stack0.CopyFrom(
-        thr->trace.headers[i].stack0);
+static bool FindThreadByUid(ThreadContextBase *tctx, void *arg) {
+  uptr uid = (uptr)arg;
+  if (tctx->user_id == uid && tctx->status != ThreadStatusInvalid) {
+    tctx->user_id = 0;
+    return true;
   }
-  tctx->epoch1 = thr->fast_state.epoch();
-
-#ifndef TSAN_GO
-  AllocatorThreadFinish(thr);
-#endif
-  thr->~ThreadState();
-  StatAggregate(ctx->stat, thr->stat);
-  tctx->thr = 0;
+  return false;
 }
 
 int ThreadTid(ThreadState *thr, uptr pc, uptr uid) {
   CHECK_GT(thr->in_rtl, 0);
   Context *ctx = CTX();
-  Lock l(&ctx->thread_mtx);
-  int res = -1;
-  for (unsigned tid = 0; tid < kMaxTid; tid++) {
-    ThreadContext *tctx = ctx->threads[tid];
-    if (tctx != 0 && tctx->user_id == uid
-        && tctx->status != ThreadStatusInvalid) {
-      tctx->user_id = 0;
-      res = tid;
-      break;
-    }
-  }
+  int res = ctx->thread_registry->FindThread(FindThreadByUid, (void*)uid);
   DPrintf("#%d: ThreadTid uid=%zu tid=%d\n", thr->tid, uid, res);
   return res;
 }
@@ -301,18 +275,7 @@ void ThreadJoin(ThreadState *thr, uptr pc, int tid) {
   CHECK_LT(tid, kMaxTid);
   DPrintf("#%d: ThreadJoin tid=%d\n", thr->tid, tid);
   Context *ctx = CTX();
-  Lock l(&ctx->thread_mtx);
-  ThreadContext *tctx = ctx->threads[tid];
-  if (tctx->status == ThreadStatusInvalid) {
-    Printf("ThreadSanitizer: join of non-existent thread\n");
-    return;
-  }
-  // FIXME(dvyukov): print message and continue (it's user error).
-  CHECK_EQ(tctx->detached, false);
-  CHECK_EQ(tctx->status, ThreadStatusFinished);
-  thr->clock.acquire(&tctx->sync);
-  StatInc(thr, StatSyncAcquire);
-  ThreadDead(thr, tctx);
+  ctx->thread_registry->JoinThread(tid, thr);
 }
 
 void ThreadDetach(ThreadState *thr, uptr pc, int tid) {
@@ -320,31 +283,12 @@ void ThreadDetach(ThreadState *thr, uptr pc, int tid) {
   CHECK_GT(tid, 0);
   CHECK_LT(tid, kMaxTid);
   Context *ctx = CTX();
-  Lock l(&ctx->thread_mtx);
-  ThreadContext *tctx = ctx->threads[tid];
-  if (tctx->status == ThreadStatusInvalid) {
-    Printf("ThreadSanitizer: detach of non-existent thread\n");
-    return;
-  }
-  if (tctx->status == ThreadStatusFinished) {
-    ThreadDead(thr, tctx);
-  } else {
-    tctx->detached = true;
-  }
+  ctx->thread_registry->DetachThread(tid);
 }
 
 void ThreadSetName(ThreadState *thr, const char *name) {
-  Context *ctx = CTX();
-  Lock l(&ctx->thread_mtx);
-  ThreadContext *tctx = ctx->threads[thr->tid];
-  CHECK_NE(tctx, 0);
-  CHECK_EQ(tctx->status, ThreadStatusRunning);
-  if (tctx->name) {
-    internal_free(tctx->name);
-    tctx->name = 0;
-  }
-  if (name)
-    tctx->name = internal_strdup(name);
+  CHECK_GT(thr->in_rtl, 0);
+  CTX()->thread_registry->SetThreadName(thr->tid, name);
 }
 
 void MemoryAccessRange(ThreadState *thr, uptr pc, uptr addr,
@@ -379,6 +323,13 @@ void MemoryAccessRange(ThreadState *thr, uptr pc, uptr addr,
 
   StatInc(thr, StatMopRange);
 
+  if (*shadow_mem == kShadowRodata) {
+    // Access to .rodata section, no races here.
+    // Measurements show that it can be 10-20% of all memory accesses.
+    StatInc(thr, StatMopRangeRodata);
+    return;
+  }
+
   FastState fast_state = thr->fast_state;
   if (fast_state.GetIgnoreBit())
     return;
@@ -421,25 +372,4 @@ void MemoryAccessRange(ThreadState *thr, uptr pc, uptr addr,
   }
 }
 
-void MemoryAccessRangeStep(ThreadState *thr, uptr pc, uptr addr,
-    uptr size, uptr step, bool is_write) {
-  if (size == 0)
-    return;
-  FastState fast_state = thr->fast_state;
-  if (fast_state.GetIgnoreBit())
-    return;
-  StatInc(thr, StatMopRange);
-  fast_state.IncrementEpoch();
-  thr->fast_state = fast_state;
-  TraceAddEvent(thr, fast_state, EventTypeMop, pc);
-
-  for (uptr addr_end = addr + size; addr < addr_end; addr += step) {
-    u64 *shadow_mem = (u64*)MemToShadow(addr);
-    Shadow cur(fast_state);
-    cur.SetWrite(is_write);
-    cur.SetAddr0AndSizeLog(addr & (kShadowCell - 1), kSizeLog1);
-    MemoryAccessImpl(thr, addr, kSizeLog1, is_write, false,
-        shadow_mem, cur);
-  }
-}
 }  // namespace __tsan