1.1 --- a/src/share/vm/oops/constantPool.cpp Mon Nov 03 12:02:40 2014 -0800
1.2 +++ b/src/share/vm/oops/constantPool.cpp Thu Oct 02 10:55:36 2014 +0200
1.3 @@ -1817,11 +1817,22 @@
1.4
1.5 void ConstantPool::set_on_stack(const bool value) {
1.6 if (value) {
1.7 - _flags |= _on_stack;
1.8 + int old_flags = *const_cast<volatile int *>(&_flags);
1.9 + while ((old_flags & _on_stack) == 0) {
1.10 + int new_flags = old_flags | _on_stack;
1.11 + int result = Atomic::cmpxchg(new_flags, &_flags, old_flags);
1.12 +
1.13 + if (result == old_flags) {
1.14 + // Succeeded.
1.15 + MetadataOnStackMark::record(this, Thread::current());
1.16 + return;
1.17 + }
1.18 + old_flags = result;
1.19 + }
1.20 } else {
1.21 + // Clearing is done single-threadedly.
1.22 _flags &= ~_on_stack;
1.23 }
1.24 - if (value) MetadataOnStackMark::record(this);
1.25 }
1.26
1.27 // JSR 292 support for patching constant pool oops after the class is linked and
