graal-compiler: src/share/vm/oops/constantPool.cpp comparison

comparison src/share/vm/oops/constantPool.cpp @ 10152:c115fac239eb

8008962: NPG: Memory regression: One extra Monitor per ConstantPool Summary: Re-use InstanceKlass::_init_lock locking ConstantPool as well. Reviewed-by: dholmes, coleenp, acorn

author	iklam
date	Thu, 25 Apr 2013 12:55:49 -0700
parents	15a99ca4ee34
children	51af5fae397d

comparison

equal deleted inserted replaced

-:15a99ca4ee34
+:c115fac239eb
 #include "oops/objArrayKlass.hpp"
 #include "runtime/fieldType.hpp"
 #include "runtime/init.hpp"
 #include "runtime/javaCalls.hpp"
 #include "runtime/signature.hpp"
+#include "runtime/synchronizer.hpp"
 #include "runtime/vframe.hpp"
 ConstantPool* ConstantPool::allocate(ClassLoaderData* loader_data, int length, TRAPS) {
 // Tags are RW but comment below applies to tags also.
 Array<u1>* tags = MetadataFactory::new_writeable_array<u1>(loader_data, length, 0, CHECK_NULL);
 set_pool_holder(NULL);
 set_flags(0);
 // only set to non-zero if constant pool is merged by RedefineClasses
 set_version(0);
-set_lock(new Monitor(Monitor::nonleaf + 2, "A constant pool lock"));
 // initialize tag array
 int length = tags->length();
 for (int index = 0; index < length; index++) {
 tags->at_put(index, JVM_CONSTANT_Invalid);
 }
 void ConstantPool::release_C_heap_structures() {
 // walk constant pool and decrement symbol reference counts
 unreference_symbols();
-delete _lock;
-set_lock(NULL);
 }
 objArrayOop ConstantPool::resolved_references() const {
 return (objArrayOop)JNIHandles::resolve(_resolved_references);
 }
 Handle refs_handle (THREAD, (oop)stom);  // must handleize.
 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
 set_resolved_references(loader_data->add_handle(refs_handle));
 }
-// Also need to recreate the mutex.  Make sure this matches the constructor
-set_lock(new Monitor(Monitor::nonleaf + 2, "A constant pool lock"));
 }
 }
 void ConstantPool::remove_unshareable_info() {
 // Resolved references are not in the shared archive.
 // Save the length for restoration.  It is not necessarily the same length
 // as reference_map.length() if invokedynamic is saved.
 set_resolved_reference_length(
 resolved_references() != NULL ? resolved_references()->length() : 0);
 set_resolved_references(NULL);
-set_lock(NULL);
+}
+oop ConstantPool::lock() {
+if (_pool_holder) {
+// We re-use the _pool_holder's init_lock to reduce footprint.
+// Notes on deadlocks:
+// [1] This lock is a Java oop, so it can be recursively locked by
+//     the same thread without self-deadlocks.
+// [2] Deadlock will happen if there is circular dependency between
+//     the <clinit> of two Java classes. However, in this case,
+//     the deadlock would have happened long before we reach
+//     ConstantPool::lock(), so reusing init_lock does not
+//     increase the possibility of deadlock.
+return _pool_holder->init_lock();
+} else {
+return NULL;
+}
 }
 int ConstantPool::cp_to_object_index(int cp_index) {
 // this is harder don't do this so much.
 for (int i = 0; i< reference_map()->length(); i++) {
 // until the loader_data is registered.
 Handle mirror_handle;
 Symbol* name = NULL;
 Handle       loader;
-{  MonitorLockerEx ml(this_oop->lock());
+{
+oop cplock = this_oop->lock();
+ObjectLocker ol(cplock , THREAD, cplock != NULL);
 if (this_oop->tag_at(which).is_unresolved_klass()) {
 if (this_oop->tag_at(which).is_unresolved_klass_in_error()) {
 in_error = true;
 } else {
 ResourceMark rm;
 Symbol* error = PENDING_EXCEPTION->klass()->name();
 bool throw_orig_error = false;
 {
-MonitorLockerEx ml(this_oop->lock());
+oop cplock = this_oop->lock();
+ObjectLocker ol(cplock, THREAD, cplock != NULL);
 // some other thread has beaten us and has resolved the class.
 if (this_oop->tag_at(which).is_klass()) {
 CLEAR_PENDING_EXCEPTION;
 entry = this_oop->resolved_klass_at(which);
 InstanceKlass::cast(k())->external_name());
 }
 }
 return k();
 } else {
-MonitorLockerEx ml(this_oop->lock());
+oop cplock = this_oop->lock();
+ObjectLocker ol(cplock, THREAD, cplock != NULL);
 // Only updated constant pool - if it is resolved.
 do_resolve = this_oop->tag_at(which).is_unresolved_klass();
 if (do_resolve) {
 ClassLoaderData* this_key = this_oop->pool_holder()->class_loader_data();
 this_key->record_dependency(k(), CHECK_NULL); // Can throw OOM
 // in the resolution error table, so that the same exception is thrown again.
 void ConstantPool::save_and_throw_exception(constantPoolHandle this_oop, int which,
 int tag, TRAPS) {
 ResourceMark rm;
 Symbol* error = PENDING_EXCEPTION->klass()->name();
-MonitorLockerEx ml(this_oop->lock());  // lock cpool to change tag.
+oop cplock = this_oop->lock();
+ObjectLocker ol(cplock, THREAD, cplock != NULL);  // lock cpool to change tag.
 int error_tag = (tag == JVM_CONSTANT_MethodHandle) ?
 JVM_CONSTANT_MethodHandleInError : JVM_CONSTANT_MethodTypeInError;
 if (!PENDING_EXCEPTION->
 }
 if (cache_index >= 0) {
 // Cache the oop here also.
 Handle result_handle(THREAD, result_oop);
-MonitorLockerEx ml(this_oop->lock());  // don't know if we really need this
+oop cplock = this_oop->lock();
+ObjectLocker ol(cplock, THREAD, cplock != NULL);  // don't know if we really need this
 oop result = this_oop->resolved_references()->obj_at(cache_index);
 // Benign race condition:  resolved_references may already be filled in while we were trying to lock.
 // The important thing here is that all threads pick up the same result.
 // It doesn't matter which racing thread wins, as long as only one
 // result is used by all threads, and all future queries.

Mercurial > hg > graal-compiler

comparison src/share/vm/oops/constantPool.cpp @ 10152:c115fac239eb