diff --git a/src/hotspot/share/classfile/classLoaderData.hpp b/src/hotspot/share/classfile/classLoaderData.hpp index 0e60fe0..24706ca 100644 --- a/src/hotspot/share/classfile/classLoaderData.hpp +++ b/src/hotspot/share/classfile/classLoaderData.hpp @@ -336,6 +336,8 @@ class ClassLoaderData : public CHeapObj { bool claimed() const { return _claimed == 1; } bool claim(); + // Computes if the CLD is alive or not. This is safe to call in concurrent + // contexts. bool is_alive() const; // Accessors @@ -377,6 +379,9 @@ class ClassLoaderData : public CHeapObj { inline oop class_loader() const; // Returns true if this class loader data is for a loader going away. + // Note that this is only safe after the GC has computed if the CLD is + // unloaded or not. In concurrent contexts where there are no such + // guarantees, is_alive() should be used instead. bool is_unloading() const { assert(!(is_the_null_class_loader_data() && _unloading), "The null class loader can never be unloaded"); return _unloading; diff --git a/src/hotspot/share/classfile/classLoaderHierarchyDCmd.cpp b/src/hotspot/share/classfile/classLoaderHierarchyDCmd.cpp index 59948ff..332838d 100644 --- a/src/hotspot/share/classfile/classLoaderHierarchyDCmd.cpp +++ b/src/hotspot/share/classfile/classLoaderHierarchyDCmd.cpp @@ -470,7 +470,7 @@ public: void do_cld (ClassLoaderData* cld) { // We do not display unloading loaders, for now. - if (cld->is_unloading()) { + if (!cld->is_alive()) { return; } diff --git a/src/hotspot/share/oops/klass.hpp b/src/hotspot/share/oops/klass.hpp index c60d216..efeeb17 100644 --- a/src/hotspot/share/oops/klass.hpp +++ b/src/hotspot/share/oops/klass.hpp @@ -657,7 +657,7 @@ protected: // Iff the class loader (or mirror for unsafe anonymous classes) is alive the // Klass is considered alive. Has already been marked as unloading. - bool is_loader_alive() const { return !class_loader_data()->is_unloading(); } + bool is_loader_alive() const { return class_loader_data()->is_alive(); } // Load the klass's holder as a phantom. This is useful when a weak Klass // pointer has been "peeked" and then must be kept alive before it may