Slow down timers for ubsan builds

Makefile

@@ -174,7 +174,7 @@ LD_ubsan = clang
 LDXX_ubsan = clang++
 CPPFLAGS_ubsan = -O0 -fsanitize-coverage=edge -fsanitize=undefined -fno-omit-frame-pointer -Wno-unused-command-line-argument -Wvarargs
 LDFLAGS_ubsan = -fsanitize=undefined,unsigned-integer-overflow
-DEFINES_ubsan = NDEBUG
+DEFINES_ubsan = NDEBUG GRPC_UBSAN
 
 VALID_CONFIG_tsan = 1
 REQUIRE_CUSTOM_LIBRARIES_tsan = 1

build.yaml

@@ -4464,7 +4464,7 @@ configs:
     CPPFLAGS: -O0 -fsanitize-coverage=edge -fsanitize=undefined -fno-omit-frame-pointer
       -Wno-unused-command-line-argument -Wvarargs
     CXX: clang++
-    DEFINES: NDEBUG
+    DEFINES: NDEBUG GRPC_UBSAN
     LD: clang
     LDFLAGS: -fsanitize=undefined,unsigned-integer-overflow
     LDXX: clang++

test/core/util/test_config.c

@@ -348,6 +348,14 @@ bool BuiltUnderMsan() {
 #endif
 }
 
+bool BuiltUnderUbsan() {
+#ifdef GRPC_UBSAN
+  return true;
+#else
+  return false;
+#endif
+}
+
 int64_t grpc_test_sanitizer_slowdown_factor() {
   int64_t sanitizer_multiplier = 1;
   if (BuiltUnderValgrind()) {
@@ -358,6 +366,8 @@ int64_t grpc_test_sanitizer_slowdown_factor() {
     sanitizer_multiplier = 3;
   } else if (BuiltUnderMsan()) {
     sanitizer_multiplier = 4;
+  } else if (BuiltUnderUbsan()) {
+    sanitizer_multiplier = 5;
   }
   return sanitizer_multiplier;
 }