tsan: add "as if synchronized via sleep" feature

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@163006 91177308-0d34-0410-b5e6-96231b3b80d8

9 files changed, 99 insertions, 8 deletions

diff --git a/lib/tsan/rtl/tsan_interceptors.cc b/lib/tsan/rtl/tsan_interceptors.cc
index 1dce12bca..f0a46ac61 100644
--- a/lib/tsan/rtl/tsan_interceptors.cc
+++ b/lib/tsan/rtl/tsan_interceptors.cc
@@ -51,7 +51,6 @@ extern "C" void *pthread_self();
 extern "C" void _exit(int status);
 extern "C" int __cxa_atexit(void (*func)(void *arg), void *arg, void *dso);
 extern "C" int *__errno_location();
-extern "C" int usleep(unsigned usec);
 const int PTHREAD_MUTEX_RECURSIVE = 1;
 const int PTHREAD_MUTEX_RECURSIVE_NP = 1;
 const int kPthreadAttrSize = 56;
@@ -213,6 +212,27 @@ static void invoke_free_hook(void *ptr) {
   __tsan_free_hook(ptr);
 }
 
+TSAN_INTERCEPTOR(unsigned, sleep, unsigned sec) {
+  SCOPED_TSAN_INTERCEPTOR(sleep, sec);
+  unsigned res = sleep(sec);
+  AfterSleep(thr, pc);
+  return res;
+}
+
+TSAN_INTERCEPTOR(int, usleep, long_t usec) {
+  SCOPED_TSAN_INTERCEPTOR(usleep, usec);
+  int res = usleep(usec);
+  AfterSleep(thr, pc);
+  return res;
+}
+
+TSAN_INTERCEPTOR(int, nanosleep, void *req, void *rem) {
+  SCOPED_TSAN_INTERCEPTOR(nanosleep, req, rem);
+  int res = nanosleep(req, rem);
+  AfterSleep(thr, pc);
+  return res;
+}
+
 class AtExitContext {
  public:
   AtExitContext()
@@ -269,7 +289,7 @@ static void finalize(void *arg) {
   {
     ScopedInRtl in_rtl;
     DestroyAndFree(atexit_ctx);
-    usleep(flags()->atexit_sleep_ms * 1000);
+    REAL(usleep)(flags()->atexit_sleep_ms * 1000);
   }
   int status = Finalize(cur_thread());
   if (status)
@@ -1572,6 +1592,9 @@ void InitializeInterceptors() {
   TSAN_INTERCEPT(raise);
   TSAN_INTERCEPT(kill);
   TSAN_INTERCEPT(pthread_kill);
+  TSAN_INTERCEPT(sleep);
+  TSAN_INTERCEPT(usleep);
+  TSAN_INTERCEPT(nanosleep);
 
   atexit_ctx = new(internal_alloc(MBlockAtExit, sizeof(AtExitContext)))
       AtExitContext();
diff --git a/lib/tsan/rtl/tsan_mman.cc b/lib/tsan/rtl/tsan_mman.cc
index ba8972f4c..1e1022bcd 100644
--- a/lib/tsan/rtl/tsan_mman.cc
+++ b/lib/tsan/rtl/tsan_mman.cc
@@ -12,7 +12,6 @@
 //===----------------------------------------------------------------------===//
 #include "sanitizer_common/sanitizer_common.h"
 #include "sanitizer_common/sanitizer_placement_new.h"
-#include "sanitizer_common/sanitizer_stackdepot.h"
 #include "tsan_mman.h"
 #include "tsan_rtl.h"
 #include "tsan_report.h"
@@ -51,10 +50,7 @@ void *user_alloc(ThreadState *thr, uptr pc, uptr sz, uptr align) {
   MBlock *b = (MBlock*)allocator()->GetMetaData(p);
   b->size = sz;
   b->alloc_tid = thr->unique_id;
-  b->alloc_stack_id = 0;
-  if (thr->shadow_stack_pos)  // May happen during bootstrap.
-    b->alloc_stack_id = StackDepotPut(thr->shadow_stack,
-        thr->shadow_stack_pos - thr->shadow_stack);
+  b->alloc_stack_id = CurrentStackId(thr, pc);
   if (CTX() && CTX()->initialized) {
     MemoryRangeImitateWrite(thr, pc, (uptr)p, sz);
   }
diff --git a/lib/tsan/rtl/tsan_report.cc b/lib/tsan/rtl/tsan_report.cc
index 6ce164bcf..c95ca8f20 100644
--- a/lib/tsan/rtl/tsan_report.cc
+++ b/lib/tsan/rtl/tsan_report.cc
@@ -21,7 +21,8 @@ ReportDesc::ReportDesc()
     , mops(MBlockReportMop)
     , locs(MBlockReportLoc)
     , mutexes(MBlockReportMutex)
-    , threads(MBlockReportThread) {
+    , threads(MBlockReportThread)
+    , sleep() {
 }
 
 ReportDesc::~ReportDesc() {
@@ -110,6 +111,11 @@ static void PrintThread(const ReportThread *rt) {
   PrintStack(rt->stack);
 }
 
+static void PrintSleep(const ReportStack *s) {
+  TsanPrintf("  As if synchronized via sleep:\n");
+  PrintStack(s);
+}
+
 void PrintReport(const ReportDesc *rep) {
   TsanPrintf("==================\n");
   PrintHeader(rep->typ);
@@ -123,6 +129,9 @@ void PrintReport(const ReportDesc *rep) {
   for (uptr i = 0; i < rep->mops.Size(); i++)
     PrintMop(rep->mops[i], i == 0);
 
+  if (rep->sleep)
+    PrintSleep(rep->sleep);
+
   for (uptr i = 0; i < rep->locs.Size(); i++)
     PrintLocation(rep->locs[i]);
 
diff --git a/lib/tsan/rtl/tsan_report.h b/lib/tsan/rtl/tsan_report.h
index d139296d5..a447d56b6 100644
--- a/lib/tsan/rtl/tsan_report.h
+++ b/lib/tsan/rtl/tsan_report.h
@@ -85,6 +85,7 @@ class ReportDesc {
   Vector<ReportLocation*> locs;
   Vector<ReportMutex*> mutexes;
   Vector<ReportThread*> threads;
+  ReportStack *sleep;
 
   ReportDesc();
   ~ReportDesc();
diff --git a/lib/tsan/rtl/tsan_rtl.cc b/lib/tsan/rtl/tsan_rtl.cc
index 9ca295da8..962c07a5b 100644
--- a/lib/tsan/rtl/tsan_rtl.cc
+++ b/lib/tsan/rtl/tsan_rtl.cc
@@ -15,6 +15,7 @@
 #include "sanitizer_common/sanitizer_atomic.h"
 #include "sanitizer_common/sanitizer_common.h"
 #include "sanitizer_common/sanitizer_libc.h"
+#include "sanitizer_common/sanitizer_stackdepot.h"
 #include "sanitizer_common/sanitizer_placement_new.h"
 #include "tsan_defs.h"
 #include "tsan_platform.h"
@@ -223,6 +224,20 @@ int Finalize(ThreadState *thr) {
   return failed ? flags()->exitcode : 0;
 }
 
+u32 CurrentStackId(ThreadState *thr, uptr pc) {
+  if (thr->shadow_stack_pos == 0)  // May happen during bootstrap.
+    return 0;
+  if (pc) {
+    thr->shadow_stack_pos[0] = pc;
+    thr->shadow_stack_pos++;
+  }
+  u32 id = StackDepotPut(thr->shadow_stack,
+                         thr->shadow_stack_pos - thr->shadow_stack);
+  if (pc)
+    thr->shadow_stack_pos--;
+  return id;
+}
+
 void TraceSwitch(ThreadState *thr) {
   thr->nomalloc++;
   ScopedInRtl in_rtl;
diff --git a/lib/tsan/rtl/tsan_rtl.h b/lib/tsan/rtl/tsan_rtl.h
index bc621cd30..d79af1e5c 100644
--- a/lib/tsan/rtl/tsan_rtl.h
+++ b/lib/tsan/rtl/tsan_rtl.h
@@ -286,6 +286,11 @@ struct ThreadState {
   bool in_signal_handler;
   SignalContext *signal_ctx;
 
+#ifndef TSAN_GO
+  u32 last_sleep_stack_id;
+  ThreadClock last_sleep_clock;
+#endif
+
   // Set in regions of runtime that must be signal-safe and fork-safe.
   // If set, malloc must not be called.
   int nomalloc;
@@ -405,6 +410,7 @@ class ScopedReport {
   void AddThread(const ThreadContext *tctx);
   void AddMutex(const SyncVar *s);
   void AddLocation(uptr addr, uptr size);
+  void AddSleep(u32 stack_id);
 
   const ReportDesc *GetReport() const;
 
@@ -446,6 +452,8 @@ bool IsExpectedReport(uptr addr, uptr size);
 # define DPrintf2(...)
 #endif
 
+u32 CurrentStackId(ThreadState *thr, uptr pc);
+
 void Initialize(ThreadState *thr);
 int Finalize(ThreadState *thr);
 
@@ -489,6 +497,7 @@ void MutexReadOrWriteUnlock(ThreadState *thr, uptr pc, uptr addr);
 void Acquire(ThreadState *thr, uptr pc, uptr addr);
 void Release(ThreadState *thr, uptr pc, uptr addr);
 void ReleaseStore(ThreadState *thr, uptr pc, uptr addr);
+void AfterSleep(ThreadState *thr, uptr pc);
 
 // The hacky call uses custom calling convention and an assembly thunk.
 // It is considerably faster that a normal call for the caller
diff --git a/lib/tsan/rtl/tsan_rtl_mutex.cc b/lib/tsan/rtl/tsan_rtl_mutex.cc
index 167541f0f..a743924db 100644
--- a/lib/tsan/rtl/tsan_rtl_mutex.cc
+++ b/lib/tsan/rtl/tsan_rtl_mutex.cc
@@ -230,4 +230,21 @@ void ReleaseStore(ThreadState *thr, uptr pc, uptr addr) {
   s->mtx.Unlock();
 }
 
+#ifndef TSAN_GO
+void AfterSleep(ThreadState *thr, uptr pc) {
+  Context *ctx = CTX();
+  thr->last_sleep_stack_id = CurrentStackId(thr, pc);
+  Lock l(&ctx->thread_mtx);
+  for (unsigned i = 0; i < kMaxTid; i++) {
+    ThreadContext *tctx = ctx->threads[i];
+    if (tctx == 0)
+      continue;
+    if (tctx->status == ThreadStatusRunning)
+      thr->last_sleep_clock.set(i, tctx->thr->fast_state.epoch());
+    else
+      thr->last_sleep_clock.set(i, tctx->epoch1);
+  }
+}
+#endif
+
 }  // namespace __tsan
diff --git a/lib/tsan/rtl/tsan_rtl_report.cc b/lib/tsan/rtl/tsan_rtl_report.cc
index a32d30a1b..8173700d0 100644
--- a/lib/tsan/rtl/tsan_rtl_report.cc
+++ b/lib/tsan/rtl/tsan_rtl_report.cc
@@ -230,6 +230,16 @@ void ScopedReport::AddLocation(uptr addr, uptr size) {
   }
 }
 
+void ScopedReport::AddSleep(u32 stack_id) {
+  uptr ssz = 0;
+  const uptr *stack = StackDepotGet(stack_id, &ssz);
+  if (stack) {
+    StackTrace trace;
+    trace.Init(stack, ssz);
+    rep_->sleep = SymbolizeStack(trace);
+  }
+}
+
 const ReportDesc *ScopedReport::GetReport() const {
   return rep_;
 }
@@ -411,6 +421,14 @@ void ReportRace(ThreadState *thr) {
 
   rep.AddLocation(addr_min, addr_max - addr_min);
 
+#ifndef TSAN_GO
+  {  // NOLINT
+    Shadow s(thr->racy_state[1]);
+    if (s.epoch() <= thr->last_sleep_clock.get(s.tid()))
+      rep.AddSleep(thr->last_sleep_stack_id);
+  }
+#endif
+
   if (!OutputReport(rep, rep.GetReport()->mops[0]->stack))
     return;
 
diff --git a/lib/tsan/rtl/tsan_stat.h b/lib/tsan/rtl/tsan_stat.h
index 6bc5d230f..d99491f74 100644
--- a/lib/tsan/rtl/tsan_stat.h
+++ b/lib/tsan/rtl/tsan_stat.h
@@ -199,6 +199,9 @@ enum StatType {
   StatInt_raise,
   StatInt_kill,
   StatInt_pthread_kill,
+  StatInt_sleep,
+  StatInt_usleep,
+  StatInt_nanosleep,
 
   // Dynamic annotations.
   StatAnnotation,