Fix races in TestMemoryPressure.

fuse/pressure_test.go

@@ -54,11 +54,11 @@ func TestMemoryPressure(t *testing.T) {
 	if err != nil {
 		t.Fatalf("mount failed: %v", err)
 	}
+	state.Debug = VerboseTest()
+
 	go state.Loop()
 	defer state.Unmount()
 
-	state.Debug = VerboseTest()
-
 	// Wait for FS to get ready.
 	os.Lstat(dir)
 
@@ -75,7 +75,12 @@ func TestMemoryPressure(t *testing.T) {
 		}(i)
 	}
 	time.Sleep(100 * time.Millisecond)
+
+	state.reqMu.Lock()
+	bufs.lock.Lock()
 	created := bufs.createdBuffers + state.outstandingReadBufs
+	bufs.lock.Unlock()
+	state.reqMu.Unlock()
 
 	t.Logf("Have %d read bufs", state.outstandingReadBufs)
 	if created > _MAX_READERS {