tsan: remove "expected" races

[dvyukov]

Summary

"Expected" races is a very ancient facility used in tsanv1 tests.
It's not used/needed anymore. Remove it.

compiler-rt/lib/tsan/rtl/tsan_flags.inc

TSAN_FLAG(bool, report_signal_unsafe, true,
           "Report violations of async signal-safety "
           "(e.g. malloc() call from a signal handler).")
 TSAN_FLAG(bool, report_atomic_races, true,
           "Report races between atomic and plain memory accesses.")
 TSAN_FLAG(
     bool, force_seq_cst_atomics, false,
     "If set, all atomics are effectively sequentially consistent (seq_cst), "
     "regardless of what user actually specified.")
-TSAN_FLAG(bool, print_benign, false, "Print matched \"benign\" races at exit.")
 TSAN_FLAG(bool, halt_on_error, false, "Exit after first reported error.")
 TSAN_FLAG(int, atexit_sleep_ms, 1000,
           "Sleep in main thread before exiting for that many ms "
           "(useful to catch \"at exit\" races).")
 TSAN_FLAG(const char *, profile_memory, "",
           "If set, periodically write memory profile to that file.")
 TSAN_FLAG(int, flush_memory_ms, 0, "Flush shadow memory every X ms.")
 TSAN_FLAG(int, flush_symbolizer_ms, 5000, "Flush symbolizer caches every X ms.")

compiler-rt/lib/tsan/rtl/tsan_interface_ann.cpp

struct ExpectRace {
   uptr size;
   char *file;
   int line;
   char desc[kMaxDescLen];
 };
 
 struct DynamicAnnContext {
   Mutex mtx;
-  ExpectRace expect;
   ExpectRace benign;
 
   DynamicAnnContext() : mtx(MutexTypeAnnotations) {}
 };
 
 static DynamicAnnContext *dyn_ann_ctx;
 static char dyn_ann_ctx_placeholder[sizeof(DynamicAnnContext)] ALIGNED(64);
 

 
 static void InitList(ExpectRace *list) {
   list->next = list;
   list->prev = list;
 }
 
 void InitializeDynamicAnnotations() {
   dyn_ann_ctx = new(dyn_ann_ctx_placeholder) DynamicAnnContext;
-  InitList(&dyn_ann_ctx->expect);
   InitList(&dyn_ann_ctx->benign);
 }
 
 bool IsExpectedReport(uptr addr, uptr size) {
   ReadLock lock(&dyn_ann_ctx->mtx);
-  if (CheckContains(&dyn_ann_ctx->expect, addr, size))
-    return true;
-  if (CheckContains(&dyn_ann_ctx->benign, addr, size))
-    return true;
-  return false;
-}
-
-static void CollectMatchedBenignRaces(Vector<ExpectRace> *matched,
-    int *unique_count, int *hit_count, atomic_uintptr_t ExpectRace::*counter) {
-  ExpectRace *list = &dyn_ann_ctx->benign;
-  for (ExpectRace *race = list->next; race != list; race = race->next) {
-    (*unique_count)++;
-    const uptr cnt = atomic_load_relaxed(&(race->*counter));
-    if (cnt == 0)
-      continue;
-    *hit_count += cnt;
-    uptr i = 0;
-    for (; i < matched->Size(); i++) {
-      ExpectRace *race0 = &(*matched)[i];
-      if (race->line == race0->line
-          && internal_strcmp(race->file, race0->file) == 0
-          && internal_strcmp(race->desc, race0->desc) == 0) {
-        atomic_fetch_add(&(race0->*counter), cnt, memory_order_relaxed);
-        break;
-      }
-    }
-    if (i == matched->Size())
-      matched->PushBack(*race);
-  }
-}
-
-void PrintMatchedBenignRaces() {
-  Lock lock(&dyn_ann_ctx->mtx);
-  int unique_count = 0;
-  int hit_count = 0;
-  int add_count = 0;
-  Vector<ExpectRace> hit_matched;
-  CollectMatchedBenignRaces(&hit_matched, &unique_count, &hit_count,
-      &ExpectRace::hitcount);
-  Vector<ExpectRace> add_matched;
-  CollectMatchedBenignRaces(&add_matched, &unique_count, &add_count,
-      &ExpectRace::addcount);
-  if (hit_matched.Size()) {
-    Printf("ThreadSanitizer: Matched %d \"benign\" races (pid=%d):\n",
-        hit_count, (int)internal_getpid());
-    for (uptr i = 0; i < hit_matched.Size(); i++) {
-      Printf("%d %s:%d %s\n",
-          atomic_load_relaxed(&hit_matched[i].hitcount),
-          hit_matched[i].file, hit_matched[i].line, hit_matched[i].desc);
-    }
-  }
-  if (hit_matched.Size()) {
-    Printf("ThreadSanitizer: Annotated %d \"benign\" races, %d unique"
-           " (pid=%d):\n",
-        add_count, unique_count, (int)internal_getpid());
-    for (uptr i = 0; i < add_matched.Size(); i++) {
-      Printf("%d %s:%d %s\n",
-          atomic_load_relaxed(&add_matched[i].addcount),
-          add_matched[i].file, add_matched[i].line, add_matched[i].desc);
-    }
-  }
-}
-
-static void ReportMissedExpectedRace(ExpectRace *race) {
-  Printf("==================\n");
-  Printf("WARNING: ThreadSanitizer: missed expected data race\n");
-  Printf("  %s addr=%zx %s:%d\n",
-      race->desc, race->addr, race->file, race->line);
-  Printf("==================\n");
+  return CheckContains(&dyn_ann_ctx->benign, addr, size);
 }
 }  // namespace __tsan
 
 using namespace __tsan;
 
 extern "C" {
 void INTERFACE_ATTRIBUTE AnnotateHappensBefore(char *f, int l, uptr addr) {
   SCOPED_ANNOTATION(AnnotateHappensBefore);
   Release(thr, pc, addr);
 }
 
 void INTERFACE_ATTRIBUTE AnnotateHappensAfter(char *f, int l, uptr addr) {
   SCOPED_ANNOTATION(AnnotateHappensAfter);
   Acquire(thr, pc, addr);
 }
 
 void INTERFACE_ATTRIBUTE AnnotateCondVarSignal(char *f, int l, uptr cv) {
-  SCOPED_ANNOTATION(AnnotateCondVarSignal);
 }
 
 void INTERFACE_ATTRIBUTE AnnotateCondVarSignalAll(char *f, int l, uptr cv) {
-  SCOPED_ANNOTATION(AnnotateCondVarSignalAll);
 }
 
 void INTERFACE_ATTRIBUTE AnnotateMutexIsNotPHB(char *f, int l, uptr mu) {
-  SCOPED_ANNOTATION(AnnotateMutexIsNotPHB);
 }
 
 void INTERFACE_ATTRIBUTE AnnotateCondVarWait(char *f, int l, uptr cv,
                                              uptr lock) {
-  SCOPED_ANNOTATION(AnnotateCondVarWait);
 }
 
 void INTERFACE_ATTRIBUTE AnnotateRWLockCreate(char *f, int l, uptr m) {
   SCOPED_ANNOTATION(AnnotateRWLockCreate);
   MutexCreate(thr, pc, m, MutexFlagWriteReentrant);
 }
 
 void INTERFACE_ATTRIBUTE AnnotateRWLockCreateStatic(char *f, int l, uptr m) {
void INTERFACE_ATTRIBUTE AnnotateRWLockReleased(char *f, int l, uptr m,
   SCOPED_ANNOTATION(AnnotateRWLockReleased);
   if (is_w)
     MutexUnlock(thr, pc, m);
   else
     MutexReadUnlock(thr, pc, m);
 }
 
 void INTERFACE_ATTRIBUTE AnnotateTraceMemory(char *f, int l, uptr mem) {
-  SCOPED_ANNOTATION(AnnotateTraceMemory);
 }
 
 void INTERFACE_ATTRIBUTE AnnotateFlushState(char *f, int l) {
-  SCOPED_ANNOTATION(AnnotateFlushState);
 }
 
 void INTERFACE_ATTRIBUTE AnnotateNewMemory(char *f, int l, uptr mem,
                                            uptr size) {
-  SCOPED_ANNOTATION(AnnotateNewMemory);
 }
 
 void INTERFACE_ATTRIBUTE AnnotateNoOp(char *f, int l, uptr mem) {
-  SCOPED_ANNOTATION(AnnotateNoOp);
 }
 
 void INTERFACE_ATTRIBUTE AnnotateFlushExpectedRaces(char *f, int l) {
-  SCOPED_ANNOTATION(AnnotateFlushExpectedRaces);
-  Lock lock(&dyn_ann_ctx->mtx);
-  while (dyn_ann_ctx->expect.next != &dyn_ann_ctx->expect) {
-    ExpectRace *race = dyn_ann_ctx->expect.next;
-    if (atomic_load_relaxed(&race->hitcount) == 0) {
-      ctx->nmissed_expected++;
-      ReportMissedExpectedRace(race);
-    }
-    race->prev->next = race->next;
-    race->next->prev = race->prev;
-    Free(race);
-  }
 }
 
 void INTERFACE_ATTRIBUTE AnnotateEnableRaceDetection(
     char *f, int l, int enable) {
-  SCOPED_ANNOTATION(AnnotateEnableRaceDetection);
-  // FIXME: Reconsider this functionality later. It may be irrelevant.
 }
 
 void INTERFACE_ATTRIBUTE AnnotateMutexIsUsedAsCondVar(
     char *f, int l, uptr mu) {
-  SCOPED_ANNOTATION(AnnotateMutexIsUsedAsCondVar);
 }
 
 void INTERFACE_ATTRIBUTE AnnotatePCQGet(
     char *f, int l, uptr pcq) {
-  SCOPED_ANNOTATION(AnnotatePCQGet);
 }
 
 void INTERFACE_ATTRIBUTE AnnotatePCQPut(
     char *f, int l, uptr pcq) {
-  SCOPED_ANNOTATION(AnnotatePCQPut);
 }
 
 void INTERFACE_ATTRIBUTE AnnotatePCQDestroy(
     char *f, int l, uptr pcq) {
-  SCOPED_ANNOTATION(AnnotatePCQDestroy);
 }
 
 void INTERFACE_ATTRIBUTE AnnotatePCQCreate(
     char *f, int l, uptr pcq) {
-  SCOPED_ANNOTATION(AnnotatePCQCreate);
 }
 
 void INTERFACE_ATTRIBUTE AnnotateExpectRace(
     char *f, int l, uptr mem, char *desc) {
-  SCOPED_ANNOTATION(AnnotateExpectRace);
-  Lock lock(&dyn_ann_ctx->mtx);
-  AddExpectRace(&dyn_ann_ctx->expect,
-                f, l, mem, 1, desc);
-  DPrintf("Add expected race: %s addr=%zx %s:%d\n", desc, mem, f, l);
 }
 
-static void BenignRaceImpl(
-    char *f, int l, uptr mem, uptr size, char *desc) {
+static void BenignRaceImpl(char *f, int l, uptr mem, uptr size, char *desc) {
   Lock lock(&dyn_ann_ctx->mtx);
   AddExpectRace(&dyn_ann_ctx->benign,
                 f, l, mem, size, desc);
   DPrintf("Add benign race: %s addr=%zx %s:%d\n", desc, mem, f, l);
 }
 
-// FIXME: Turn it off later. WTF is benign race?1?? Go talk to Hans Boehm.
 void INTERFACE_ATTRIBUTE AnnotateBenignRaceSized(
     char *f, int l, uptr mem, uptr size, char *desc) {
   SCOPED_ANNOTATION(AnnotateBenignRaceSized);
   BenignRaceImpl(f, l, mem, size, desc);
 }
 
 void INTERFACE_ATTRIBUTE AnnotateBenignRace(
     char *f, int l, uptr mem, char *desc) {

 
 void INTERFACE_ATTRIBUTE AnnotateIgnoreSyncEnd(char *f, int l) {
   SCOPED_ANNOTATION(AnnotateIgnoreSyncEnd);
   ThreadIgnoreSyncEnd(thr);
 }
 
 void INTERFACE_ATTRIBUTE AnnotatePublishMemoryRange(
     char *f, int l, uptr addr, uptr size) {
-  SCOPED_ANNOTATION(AnnotatePublishMemoryRange);
 }
 
 void INTERFACE_ATTRIBUTE AnnotateUnpublishMemoryRange(
     char *f, int l, uptr addr, uptr size) {
-  SCOPED_ANNOTATION(AnnotateUnpublishMemoryRange);
 }
 
 void INTERFACE_ATTRIBUTE AnnotateThreadName(
     char *f, int l, char *name) {
   SCOPED_ANNOTATION(AnnotateThreadName);
   ThreadSetName(thr, name);
 }
 
 // We deliberately omit the implementation of WTFAnnotateHappensBefore() and
 // WTFAnnotateHappensAfter(). Those are being used by Webkit to annotate
 // atomic operations, which should be handled by ThreadSanitizer correctly.
 void INTERFACE_ATTRIBUTE WTFAnnotateHappensBefore(char *f, int l, uptr addr) {
-  SCOPED_ANNOTATION(AnnotateHappensBefore);
 }
 
 void INTERFACE_ATTRIBUTE WTFAnnotateHappensAfter(char *f, int l, uptr addr) {
-  SCOPED_ANNOTATION(AnnotateHappensAfter);
 }
 
 void INTERFACE_ATTRIBUTE WTFAnnotateBenignRaceSized(
     char *f, int l, uptr mem, uptr sz, char *desc) {
   SCOPED_ANNOTATION(AnnotateBenignRaceSized);
   BenignRaceImpl(f, l, mem, sz, desc);
 }
 

compiler-rt/lib/tsan/rtl/tsan_rtl.h

 void ForkBefore(ThreadState *thr, uptr pc);
 void ForkParentAfter(ThreadState *thr, uptr pc);
 void ForkChildAfter(ThreadState *thr, uptr pc);
 
 void ReportRace(ThreadState *thr);
 bool OutputReport(ThreadState *thr, const ScopedReport &srep);
 bool IsFiredSuppression(Context *ctx, ReportType type, StackTrace trace);
 bool IsExpectedReport(uptr addr, uptr size);
-void PrintMatchedBenignRaces();
 
 #if defined(TSAN_DEBUG_OUTPUT) && TSAN_DEBUG_OUTPUT >= 1
 # define DPrintf Printf
 #else
 # define DPrintf(...)
 #endif
 
 #if defined(TSAN_DEBUG_OUTPUT) && TSAN_DEBUG_OUTPUT >= 2

compiler-rt/lib/tsan/rtl/tsan_rtl.cpp

#endif
   if (ctx->nmissed_expected) {
     failed = true;
     Printf("ThreadSanitizer: missed %d expected races\n",
         ctx->nmissed_expected);
   }
 
   if (common_flags()->print_suppressions)
     PrintMatchedSuppressions();
-#if !SANITIZER_GO
-  if (flags()->print_benign)
-    PrintMatchedBenignRaces();
-#endif
 
   failed = OnFinalize(failed);
 
   return failed ? common_flags()->exitcode : 0;
 }
 
 #if !SANITIZER_GO
 void ForkBefore(ThreadState *thr, uptr pc) NO_THREAD_SAFETY_ANALYSIS {

compiler-rt/lib/tsan/tests/unit/tsan_flags_test.cpp

static const char *options1 =
   " suppress_equal_addresses=0"
   " report_bugs=0"
   " report_thread_leaks=0"
   " report_destroy_locked=0"
   " report_mutex_bugs=0"
   " report_signal_unsafe=0"
   " report_atomic_races=0"
   " force_seq_cst_atomics=0"
-  " print_benign=0"
   " halt_on_error=0"
   " atexit_sleep_ms=222"
   " profile_memory=qqq"
   " flush_memory_ms=444"
   " flush_symbolizer_ms=555"
   " memory_limit_mb=666"
   " stop_on_start=0"
   " running_on_valgrind=0"
   " history_size=5"
   " io_sync=1"
   " die_after_fork=true"
   "";
 
 static const char *options2 =
   " enable_annotations=true"
   " suppress_equal_stacks=true"
   " suppress_equal_addresses=true"
   " report_bugs=true"
   " report_thread_leaks=true"
   " report_destroy_locked=true"
   " report_mutex_bugs=true"
   " report_signal_unsafe=true"
   " report_atomic_races=true"
   " force_seq_cst_atomics=true"
-  " print_benign=true"
   " halt_on_error=true"
   " atexit_sleep_ms=123"
   " profile_memory=bbbbb"
   " flush_memory_ms=234"
   " flush_symbolizer_ms=345"
   " memory_limit_mb=456"
   " stop_on_start=true"
   " running_on_valgrind=true"
   " history_size=6"
   " io_sync=2"
   " die_after_fork=false"
   "";
 
 void VerifyOptions1(Flags *f) {
   EXPECT_EQ(f->enable_annotations, 0);
   EXPECT_EQ(f->suppress_equal_stacks, 0);
   EXPECT_EQ(f->suppress_equal_addresses, 0);
   EXPECT_EQ(f->report_bugs, 0);
   EXPECT_EQ(f->report_thread_leaks, 0);
   EXPECT_EQ(f->report_destroy_locked, 0);
   EXPECT_EQ(f->report_mutex_bugs, 0);
   EXPECT_EQ(f->report_signal_unsafe, 0);
   EXPECT_EQ(f->report_atomic_races, 0);
   EXPECT_EQ(f->force_seq_cst_atomics, 0);
-  EXPECT_EQ(f->print_benign, 0);
   EXPECT_EQ(f->halt_on_error, 0);
   EXPECT_EQ(f->atexit_sleep_ms, 222);
   EXPECT_EQ(f->profile_memory, std::string("qqq"));
   EXPECT_EQ(f->flush_memory_ms, 444);
   EXPECT_EQ(f->flush_symbolizer_ms, 555);
   EXPECT_EQ(f->memory_limit_mb, 666);
   EXPECT_EQ(f->stop_on_start, 0);
   EXPECT_EQ(f->running_on_valgrind, 0);
   EXPECT_EQ(f->history_size, 5);
   EXPECT_EQ(f->io_sync, 1);
   EXPECT_EQ(f->die_after_fork, true);
 }
 
 void VerifyOptions2(Flags *f) {
   EXPECT_EQ(f->enable_annotations, true);
   EXPECT_EQ(f->suppress_equal_stacks, true);
   EXPECT_EQ(f->suppress_equal_addresses, true);
   EXPECT_EQ(f->report_bugs, true);
   EXPECT_EQ(f->report_thread_leaks, true);
   EXPECT_EQ(f->report_destroy_locked, true);
   EXPECT_EQ(f->report_mutex_bugs, true);
   EXPECT_EQ(f->report_signal_unsafe, true);
   EXPECT_EQ(f->report_atomic_races, true);
   EXPECT_EQ(f->force_seq_cst_atomics, true);
-  EXPECT_EQ(f->print_benign, true);
   EXPECT_EQ(f->halt_on_error, true);
   EXPECT_EQ(f->atexit_sleep_ms, 123);
   EXPECT_EQ(f->profile_memory, std::string("bbbbb"));
   EXPECT_EQ(f->flush_memory_ms, 234);
   EXPECT_EQ(f->flush_symbolizer_ms, 345);
   EXPECT_EQ(f->memory_limit_mb, 456);
   EXPECT_EQ(f->stop_on_start, true);
   EXPECT_EQ(f->running_on_valgrind, true);