[sanitizer] deadlock detector: a) initial support for suppressions, b) be more robust in case we failed to extract a stack trace for one of the locks

llvm-svn: 204225

compiler-rt/lib/sanitizer_common/sanitizer_suppressions.cc

@@ -20,8 +20,8 @@
 namespace __sanitizer {
 
 static const char *const kTypeStrings[SuppressionTypeCount] = {
-  "none", "race", "mutex", "thread", "signal", "leak", "called_from_lib"
-};
+    "none",   "race", "mutex",           "thread",
+    "signal", "leak", "called_from_lib", "deadlock"};
 
 bool TemplateMatch(char *templ, const char *str) {
   if (str == 0 || str[0] == 0)

compiler-rt/lib/sanitizer_common/sanitizer_suppressions.h

@@ -26,6 +26,7 @@ enum SuppressionType {
   SuppressionSignal,
   SuppressionLeak,
   SuppressionLib,
+  SuppressionDeadlock,
   SuppressionTypeCount
 };
 

compiler-rt/lib/sanitizer_common/tests/sanitizer_suppressions_test.cc

@@ -67,8 +67,10 @@ TEST(Suppressions, TypeStrings) {
   CHECK(!internal_strcmp(SuppressionTypeString(SuppressionLeak), "leak"));
   CHECK(!internal_strcmp(SuppressionTypeString(SuppressionLib),
       "called_from_lib"));
+  CHECK(
+      !internal_strcmp(SuppressionTypeString(SuppressionDeadlock), "deadlock"));
   // Ensure this test is up-to-date when suppression types are added.
-  CHECK_EQ(SuppressionTypeCount, 7);
+  CHECK_EQ(SuppressionTypeCount, 8);
 }
 
 class SuppressionContextTest : public ::testing::Test {

compiler-rt/lib/tsan/rtl/tsan_rtl_mutex.cc

@@ -428,17 +428,25 @@ void ReportDeadlock(ThreadState *thr, uptr pc, DDReport *r) {
   for (int i = 0; i < r->n; i++)
     rep.AddMutex(r->loop[i].mtx_ctx0);
   StackTrace stacks[2 * DDReport::kMaxLoopSize];
+  uptr dummy_pc = 0x42;
   for (int i = 0; i < r->n; i++) {
     uptr size;
     for (int j = 0; j < 2; j++) {
       u32 stk = r->loop[i].stk[j];
-      if (!stk) continue;
-      const uptr *trace = StackDepotGet(stk, &size);
-      stacks[i].Init(const_cast<uptr *>(trace), size);
+      if (stk) {
+        const uptr *trace = StackDepotGet(stk, &size);
+        stacks[i].Init(const_cast<uptr *>(trace), size);
+      } else {
+        // Sometimes we fail to extract the stack trace (FIXME: investigate),
+        // but we should still produce some stack trace in the report.
+        stacks[i].Init(&dummy_pc, 1);
+      }
       rep.AddStack(&stacks[i]);
     }
   }
-  OutputReport(ctx, rep);
+  // FIXME: use all stacks for suppressions, not just the second stack of the
+  // first edge.
+  OutputReport(ctx, rep, rep.GetReport()->stacks[1]);
 #endif  // TSAN_GO
 }
 

compiler-rt/lib/tsan/rtl/tsan_suppressions.cc

@@ -107,6 +107,8 @@ SuppressionType conv(ReportType typ) {
     return SuppressionSignal;
   else if (typ == ReportTypeErrnoInSignal)
     return SuppressionNone;
+  else if (typ == ReportTypeDeadlock)
+    return SuppressionDeadlock;
   Printf("ThreadSanitizer: unknown report type %d\n", typ),
   Die();
 }

compiler-rt/test/tsan/mutex_cycle2.c

@@ -1,5 +1,9 @@
 // RUN: %clangxx_tsan %s -o %t
 // RUN: TSAN_OPTIONS=detect_deadlocks=1 not %t 2>&1 | FileCheck %s
+// RUN: echo "deadlock:main" > sup
+// RUN: TSAN_OPTIONS="detect_deadlocks=1 suppressions=sup" %t
+// RUN: echo "deadlock:zzzz" > sup
+// RUN: TSAN_OPTIONS="detect_deadlocks=1 suppressions=sup" not %t 2>&1 | FileCheck %s
 #include <pthread.h>
 
 int main() {