diff --git a/libutils/Mutex_test.cpp b/libutils/Mutex_test.cpp
index 8a1805f..79f4302 100644
--- a/libutils/Mutex_test.cpp
+++ b/libutils/Mutex_test.cpp
@@ -29,4 +29,20 @@
     android::Mutex::Autolock _l(mLock);
     i = 0;
     modifyLockedVariable();
-}
\ No newline at end of file
+}
+
+TEST(Mutex, tryLock) {
+    if (mLock.tryLock() != 0) {
+        return;
+    }
+    mLock.unlock();
+}
+
+#if defined(__ANDROID__)
+TEST(Mutex, timedLock) {
+    if (mLock.timedLock(1) != 0) {
+        return;
+    }
+    mLock.unlock();
+}
+#endif
diff --git a/libutils/include/utils/Mutex.h b/libutils/include/utils/Mutex.h
index 29c2e8c..1325bf3 100644
--- a/libutils/include/utils/Mutex.h
+++ b/libutils/include/utils/Mutex.h
@@ -108,7 +108,7 @@
     void unlock() RELEASE();
 
     // lock if possible; returns 0 on success, error otherwise
-    status_t tryLock() TRY_ACQUIRE(true);
+    status_t tryLock() TRY_ACQUIRE(0);
 
 #if defined(__ANDROID__)
     // Lock the mutex, but don't wait longer than timeoutNs (relative time).
@@ -122,7 +122,7 @@
     // which is subject to NTP adjustments, and includes time during suspend,
     // so a timeout may occur even though no processes could run.
     // Not holding a partial wakelock may lead to a system suspend.
-    status_t timedLock(nsecs_t timeoutNs) TRY_ACQUIRE(true);
+    status_t timedLock(nsecs_t timeoutNs) TRY_ACQUIRE(0);
 #endif
 
     // Manages the mutex automatically. It'll be locked when Autolock is