diff -r 35cd081a64ea -r ae6179641137 hotspot/src/share/vm/oops/cpCache.cpp --- a/hotspot/src/share/vm/oops/cpCache.cpp Fri Sep 07 16:42:25 2012 -0400 +++ b/hotspot/src/share/vm/oops/cpCache.cpp Mon Sep 10 16:37:22 2012 -0700 @@ -243,17 +243,20 @@ } -void ConstantPoolCacheEntry::set_method_handle(methodHandle adapter, Handle appendix, +void ConstantPoolCacheEntry::set_method_handle(constantPoolHandle cpool, + methodHandle adapter, Handle appendix, objArrayHandle resolved_references) { - set_method_handle_common(Bytecodes::_invokehandle, adapter, appendix, resolved_references); + set_method_handle_common(cpool, Bytecodes::_invokehandle, adapter, appendix, resolved_references); } -void ConstantPoolCacheEntry::set_dynamic_call(methodHandle adapter, Handle appendix, +void ConstantPoolCacheEntry::set_dynamic_call(constantPoolHandle cpool, + methodHandle adapter, Handle appendix, objArrayHandle resolved_references) { - set_method_handle_common(Bytecodes::_invokedynamic, adapter, appendix, resolved_references); + set_method_handle_common(cpool, Bytecodes::_invokedynamic, adapter, appendix, resolved_references); } -void ConstantPoolCacheEntry::set_method_handle_common(Bytecodes::Code invoke_code, +void ConstantPoolCacheEntry::set_method_handle_common(constantPoolHandle cpool, + Bytecodes::Code invoke_code, methodHandle adapter, Handle appendix, objArrayHandle resolved_references) { @@ -261,28 +264,23 @@ // There are three words to update: flags, refs[f2], f1 (in that order). // Writers must store all other values before f1. // Readers must test f1 first for non-null before reading other fields. - // Competing writers must acquire exclusive access on the first - // write, to flags, using a compare/exchange. - // A losing writer to flags must spin until the winner writes f1, - // so that when he returns, he can use the linked cache entry. + // Competing writers must acquire exclusive access via a lock. + // A losing writer waits on the lock until the winner writes f1 and leaves + // the lock, so that when the losing writer returns, he can use the linked + // cache entry. + + MonitorLockerEx ml(cpool->lock()); + if (!is_f1_null()) { + return; + } bool has_appendix = appendix.not_null(); // Write the flags. - bool owner = - init_method_flags_atomic(as_TosState(adapter->result_type()), + set_method_flags(as_TosState(adapter->result_type()), ((has_appendix ? 1 : 0) << has_appendix_shift) | ( 1 << is_final_shift), adapter->size_of_parameters()); - if (!owner) { - // Somebody else is working on the same CPCE. Let them proceed. - while (is_f1_null()) { - // Pause momentarily on a low-level lock, to allow racing thread to win. - MutexLockerEx mu(Patching_lock, Mutex::_no_safepoint_check_flag); - os::yield(); - } - return; - } if (TraceInvokeDynamic) { tty->print_cr("set_method_handle bc=%d appendix="PTR_FORMAT"%s method="PTR_FORMAT" ",