Avoid visiting find array class cache as roots

If we visit the find array class cache as roots it will prevent
unloading for any array classes in the cache. This is not ideal
since it may take a long time for the entries to get replaced.

Also added a missed exception check in getDeclaredClasses.

Bug: 22720414

Change-Id: Id34557fd034b3e3967ef629301ee251931937849

diff --git a/runtime/class_linker.cc b/runtime/class_linker.cc
index 5ff4bc1..370ea5c 100644 (file)
--- a/runtime/class_linker.cc
+++ b/runtime/class_linker.cc
@@ -1023,9 +1023,9 @@ void ClassLinker::VisitRoots(RootVisitor* visitor, VisitRootFlags flags) {
   class_roots_.VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal));
   VisitClassRoots(visitor, flags);
   array_iftable_.VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal));
-  for (GcRoot<mirror::Class>& root : find_array_class_cache_) {
-    root.VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal));
-  }
+  // Instead of visiting the find_array_class_cache_ drop it so that it doesn't prevent class
+  // unloading if we are marking roots.
+  DropFindArrayClassCache();
 }
 
 class VisitClassLoaderClassesVisitor : public ClassLoaderVisitor {

diff --git a/runtime/native/java_lang_Class.cc b/runtime/native/java_lang_Class.cc
index 5da15df..3a73900 100644 (file)
--- a/runtime/native/java_lang_Class.cc
+++ b/runtime/native/java_lang_Class.cc
@@ -522,6 +522,10 @@ static jobjectArray Class_getDeclaredClasses(JNIEnv* env, jobject javaThis) {
   }
   if (classes == nullptr) {
     // Return an empty array instead of a null pointer.
+    if (soa.Self()->IsExceptionPending()) {
+      // Pending exception from GetDeclaredClasses.
+      return nullptr;
+    }
     mirror::Class* class_class = mirror::Class::GetJavaLangClass();
     mirror::Class* class_array_class =
         Runtime::Current()->GetClassLinker()->FindArrayClass(soa.Self(), &class_class);