# HG changeset patch # User coleenp # Date 1383316356 14400 # Node ID 910026b800b86f336e014a353400990394ec6b65 # Parent c8fc12209830fc5815286059510d1230cdd72c17 8026946: JvmtiEnv::SetBreakpoint and JvmtiEnv::ClearBreakpoint should use MethodHandle 8026948: JvmtiEnv::SetBreakpoint and JvmtiEnv::ClearBreakpoint might not work with anonymous classes Summary: Walk methods in breakpoints for marking on stack so they aren't deallocated by redefine classes. Use class_holder rather than class_loader to keep GC from reclaiming class owning the method. Reviewed-by: sspitsyn, ehelin, sla diff -r c8fc12209830 -r 910026b800b8 src/share/vm/classfile/metadataOnStackMark.cpp --- a/src/share/vm/classfile/metadataOnStackMark.cpp Thu Oct 31 14:11:02 2013 -0400 +++ b/src/share/vm/classfile/metadataOnStackMark.cpp Fri Nov 01 10:32:36 2013 -0400 @@ -27,6 +27,7 @@ #include "code/codeCache.hpp" #include "compiler/compileBroker.hpp" #include "oops/metadata.hpp" +#include "prims/jvmtiImpl.hpp" #include "runtime/synchronizer.hpp" #include "runtime/thread.hpp" #include "utilities/growableArray.hpp" @@ -48,6 +49,7 @@ Threads::metadata_do(Metadata::mark_on_stack); CodeCache::alive_nmethods_do(nmethod::mark_on_stack); CompileBroker::mark_on_stack(); + JvmtiCurrentBreakpoints::metadata_do(Metadata::mark_on_stack); } MetadataOnStackMark::~MetadataOnStackMark() { diff -r c8fc12209830 -r 910026b800b8 src/share/vm/prims/jvmtiImpl.cpp --- a/src/share/vm/prims/jvmtiImpl.cpp Thu Oct 31 14:11:02 2013 -0400 +++ b/src/share/vm/prims/jvmtiImpl.cpp Fri Nov 01 10:32:36 2013 -0400 @@ -210,6 +210,14 @@ } } +void GrowableCache::metadata_do(void f(Metadata*)) { + int len = _elements->length(); + for (int i=0; iat(i); + e->metadata_do(f); + } +} + void GrowableCache::gc_epilogue() { int len = _elements->length(); for (int i=0; imethod_holder()->class_loader_data()->class_loader(); + _class_holder = _method->method_holder()->klass_holder(); #ifdef CHECK_UNHANDLED_OOPS - // _class_loader can't be wrapped in a Handle, because JvmtiBreakpoint:s are - // eventually allocated on the heap. + // _class_holder can't be wrapped in a Handle, because JvmtiBreakpoints are + // sometimes allocated on the heap. // - // The code handling JvmtiBreakpoint:s allocated on the stack can't be - // interrupted by a GC until _class_loader is reachable by the GC via the + // The code handling JvmtiBreakpoints allocated on the stack can't be + // interrupted by a GC until _class_holder is reachable by the GC via the // oops_do method. - Thread::current()->allow_unhandled_oop(&_class_loader); + Thread::current()->allow_unhandled_oop(&_class_holder); #endif // CHECK_UNHANDLED_OOPS assert(_method != NULL, "_method != NULL"); _bci = (int) location; @@ -247,7 +255,7 @@ void JvmtiBreakpoint::copy(JvmtiBreakpoint& bp) { _method = bp._method; _bci = bp._bci; - _class_loader = bp._class_loader; + _class_holder = bp._class_holder; } bool JvmtiBreakpoint::lessThan(JvmtiBreakpoint& bp) { @@ -365,6 +373,13 @@ } } +void VM_ChangeBreakpoints::metadata_do(void f(Metadata*)) { + // Walk metadata in breakpoints to keep from being deallocated with RedefineClasses + if (_bp != NULL) { + _bp->metadata_do(f); + } +} + // // class JvmtiBreakpoints // @@ -381,6 +396,10 @@ _bps.oops_do(f); } +void JvmtiBreakpoints::metadata_do(void f(Metadata*)) { + _bps.metadata_do(f); +} + void JvmtiBreakpoints::gc_epilogue() { _bps.gc_epilogue(); } @@ -499,6 +518,12 @@ } } +void JvmtiCurrentBreakpoints::metadata_do(void f(Metadata*)) { + if (_jvmti_breakpoints != NULL) { + _jvmti_breakpoints->metadata_do(f); + } +} + void JvmtiCurrentBreakpoints::gc_epilogue() { if (_jvmti_breakpoints != NULL) { _jvmti_breakpoints->gc_epilogue(); diff -r c8fc12209830 -r 910026b800b8 src/share/vm/prims/jvmtiImpl.hpp --- a/src/share/vm/prims/jvmtiImpl.hpp Thu Oct 31 14:11:02 2013 -0400 +++ b/src/share/vm/prims/jvmtiImpl.hpp Fri Nov 01 10:32:36 2013 -0400 @@ -69,6 +69,7 @@ virtual bool lessThan(GrowableElement *e)=0; virtual GrowableElement *clone() =0; virtual void oops_do(OopClosure* f) =0; + virtual void metadata_do(void f(Metadata*)) =0; }; class GrowableCache VALUE_OBJ_CLASS_SPEC { @@ -115,6 +116,8 @@ void clear(); // apply f to every element and update the cache void oops_do(OopClosure* f); + // walk metadata to preserve for RedefineClasses + void metadata_do(void f(Metadata*)); // update the cache after a full gc void gc_epilogue(); }; @@ -148,6 +151,7 @@ void remove (int index) { _cache.remove(index); } void clear() { _cache.clear(); } void oops_do(OopClosure* f) { _cache.oops_do(f); } + void metadata_do(void f(Metadata*)) { _cache.metadata_do(f); } void gc_epilogue() { _cache.gc_epilogue(); } }; @@ -169,7 +173,7 @@ Method* _method; int _bci; Bytecodes::Code _orig_bytecode; - oop _class_loader; + oop _class_holder; // keeps _method memory from being deallocated public: JvmtiBreakpoint(); @@ -191,9 +195,15 @@ bool lessThan(GrowableElement* e) { Unimplemented(); return false; } bool equals(GrowableElement* e) { return equals((JvmtiBreakpoint&) *e); } void oops_do(OopClosure* f) { - // Mark the method loader as live - f->do_oop(&_class_loader); + // Mark the method loader as live so the Method* class loader doesn't get + // unloaded and Method* memory reclaimed. + f->do_oop(&_class_holder); } + void metadata_do(void f(Metadata*)) { + // walk metadata to preserve for RedefineClasses + f(_method); + } + GrowableElement *clone() { JvmtiBreakpoint *bp = new JvmtiBreakpoint(); bp->copy(*this); @@ -239,6 +249,7 @@ int length(); void oops_do(OopClosure* f); + void metadata_do(void f(Metadata*)); void print(); int set(JvmtiBreakpoint& bp); @@ -288,6 +299,7 @@ static inline bool is_breakpoint(address bcp); static void oops_do(OopClosure* f); + static void metadata_do(void f(Metadata*)); static void gc_epilogue(); }; @@ -332,6 +344,7 @@ VMOp_Type type() const { return VMOp_ChangeBreakpoints; } void doit(); void oops_do(OopClosure* f); + void metadata_do(void f(Metadata*)); };