src/hotspot/share/runtime/handles.cpp - platform/libcore - Git at Google

 /*
  * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  *
  */

 #include "precompiled.hpp"
 #include "memory/allocation.inline.hpp"
 #include "oops/constantPool.hpp"
 #include "oops/oop.inline.hpp"
 #include "runtime/atomic.hpp"
 #include "runtime/handles.inline.hpp"
 #include "runtime/thread.inline.hpp"

 #ifdef ASSERT
 oop* HandleArea::allocate_handle(oop obj) {
   assert(_handle_mark_nesting > 1, "memory leak: allocating handle outside HandleMark");
   assert(_no_handle_mark_nesting == 0, "allocating handle inside NoHandleMark");
   assert(oopDesc::is_oop(obj), "not an oop: " INTPTR_FORMAT, p2i(obj));
   return real_allocate_handle(obj);
 }
 #endif

 // Copy constructors and destructors for metadata handles
 // These do too much to inline.
 #define DEF_METADATA_HANDLE_FN_NOINLINE(name, type) \
 name##Handle::name##Handle(const name##Handle &h) {                    \
   _value = h._value;                                                   \
   if (_value != NULL) {                                                \
     assert(_value->is_valid(), "obj is valid");                        \
     if (h._thread != NULL) {                                           \
       assert(h._thread == Thread::current(), "thread must be current");\
       _thread = h._thread;                                             \
     } else {                                                           \
       _thread = Thread::current();                                     \
     }                                                                  \
     assert (_thread->is_in_stack((address)this), "not on stack?");     \
     _thread->metadata_handles()->push((Metadata*)_value);              \
   } else {                                                             \
     _thread = NULL;                                                    \
   }                                                                    \
 }                                                                      \
 name##Handle& name##Handle::operator=(const name##Handle &s) {         \
   remove();                                                            \
   _value = s._value;                                                   \
   if (_value != NULL) {                                                \
     assert(_value->is_valid(), "obj is valid");                        \
     if (s._thread != NULL) {                                           \
       assert(s._thread == Thread::current(), "thread must be current");\
       _thread = s._thread;                                             \
     } else {                                                           \
       _thread = Thread::current();                                     \
     }                                                                  \
     assert (_thread->is_in_stack((address)this), "not on stack?");     \
     _thread->metadata_handles()->push((Metadata*)_value);              \
   } else {                                                             \
     _thread = NULL;                                                    \
   }                                                                    \
   return *this;                                                        \
 }                                                                      \
 inline void name##Handle::remove() {                                   \
   if (_value != NULL) {                                                \
     int i = _thread->metadata_handles()->find_from_end((Metadata*)_value); \
     assert(i!=-1, "not in metadata_handles list");                     \
     _thread->metadata_handles()->remove_at(i);                         \
   }                                                                    \
 }                                                                      \
 name##Handle::~name##Handle () { remove(); }                           \

 DEF_METADATA_HANDLE_FN_NOINLINE(method, Method)
 DEF_METADATA_HANDLE_FN_NOINLINE(constantPool, ConstantPool)


 static uintx chunk_oops_do(OopClosure* f, Chunk* chunk, char* chunk_top) {
   oop* bottom = (oop*) chunk->bottom();
   oop* top    = (oop*) chunk_top;
   uintx handles_visited = top - bottom;
   assert(top >= bottom && top <= (oop*) chunk->top(), "just checking");
   // during GC phase 3, a handle may be a forward pointer that
   // is not yet valid, so loosen the assertion
   while (bottom < top) {
     f->do_oop(bottom++);
   }
   return handles_visited;
 }

 // Used for debugging handle allocation.
 NOT_PRODUCT(jint _nof_handlemarks  = 0;)

 void HandleArea::oops_do(OopClosure* f) {
   uintx handles_visited = 0;
   // First handle the current chunk. It is filled to the high water mark.
   handles_visited += chunk_oops_do(f, _chunk, _hwm);
   // Then handle all previous chunks. They are completely filled.
   Chunk* k = _first;
   while(k != _chunk) {
     handles_visited += chunk_oops_do(f, k, k->top());
     k = k->next();
   }

   if (_prev != NULL) _prev->oops_do(f);
 }

 void HandleMark::initialize(Thread* thread) {
   _thread = thread;
   // Save area
   _area  = thread->handle_area();
   // Save current top
   _chunk = _area->_chunk;
   _hwm   = _area->_hwm;
   _max   = _area->_max;
   _size_in_bytes = _area->_size_in_bytes;
   debug_only(_area->_handle_mark_nesting++);
   assert(_area->_handle_mark_nesting > 0, "must stack allocate HandleMarks");
   debug_only(Atomic::inc(&_nof_handlemarks);)

   // Link this in the thread
   set_previous_handle_mark(thread->last_handle_mark());
   thread->set_last_handle_mark(this);
 }


 HandleMark::~HandleMark() {
   HandleArea* area = _area;   // help compilers with poor alias analysis
   assert(area == _thread->handle_area(), "sanity check");
   assert(area->_handle_mark_nesting > 0, "must stack allocate HandleMarks" );
   debug_only(area->_handle_mark_nesting--);

   // Delete later chunks
   if( _chunk->next() ) {
     // reset arena size before delete chunks. Otherwise, the total
     // arena size could exceed total chunk size
     assert(area->size_in_bytes() > size_in_bytes(), "Sanity check");
     area->set_size_in_bytes(size_in_bytes());
     _chunk->next_chop();
   } else {
     assert(area->size_in_bytes() == size_in_bytes(), "Sanity check");
   }
   // Roll back arena to saved top markers
   area->_chunk = _chunk;
   area->_hwm = _hwm;
   area->_max = _max;
 #ifdef ASSERT
   // clear out first chunk (to detect allocation bugs)
   if (ZapVMHandleArea) {
     memset(_hwm, badHandleValue, _max - _hwm);
   }
   Atomic::dec(&_nof_handlemarks);
 #endif

   // Unlink this from the thread
   _thread->set_last_handle_mark(previous_handle_mark());
 }

 void* HandleMark::operator new(size_t size) throw() {
   return AllocateHeap(size, mtThread);
 }

 void* HandleMark::operator new [] (size_t size) throw() {
   return AllocateHeap(size, mtThread);
 }

 void HandleMark::operator delete(void* p) {
   FreeHeap(p);
 }

 void HandleMark::operator delete[](void* p) {
   FreeHeap(p);
 }

 #ifdef ASSERT

 NoHandleMark::NoHandleMark() {
   HandleArea* area = Thread::current()->handle_area();
   area->_no_handle_mark_nesting++;
   assert(area->_no_handle_mark_nesting > 0, "must stack allocate NoHandleMark" );
 }


 NoHandleMark::~NoHandleMark() {
   HandleArea* area = Thread::current()->handle_area();
   assert(area->_no_handle_mark_nesting > 0, "must stack allocate NoHandleMark" );
   area->_no_handle_mark_nesting--;
 }


 ResetNoHandleMark::ResetNoHandleMark() {
   HandleArea* area = Thread::current()->handle_area();
   _no_handle_mark_nesting = area->_no_handle_mark_nesting;
   area->_no_handle_mark_nesting = 0;
 }


 ResetNoHandleMark::~ResetNoHandleMark() {
   HandleArea* area = Thread::current()->handle_area();
   area->_no_handle_mark_nesting = _no_handle_mark_nesting;
 }

 #endif // ASSERT
	/*
	* Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*
	*/

	#include "precompiled.hpp"
	#include "memory/allocation.inline.hpp"
	#include "oops/constantPool.hpp"
	#include "oops/oop.inline.hpp"
	#include "runtime/atomic.hpp"
	#include "runtime/handles.inline.hpp"
	#include "runtime/thread.inline.hpp"

	#ifdef ASSERT
	oop* HandleArea::allocate_handle(oop obj) {
	assert(_handle_mark_nesting > 1, "memory leak: allocating handle outside HandleMark");
	assert(_no_handle_mark_nesting == 0, "allocating handle inside NoHandleMark");
	assert(oopDesc::is_oop(obj), "not an oop: " INTPTR_FORMAT, p2i(obj));
	return real_allocate_handle(obj);
	}
	#endif

	// Copy constructors and destructors for metadata handles
	// These do too much to inline.
	#define DEF_METADATA_HANDLE_FN_NOINLINE(name, type) \
	name##Handle::name##Handle(const name##Handle &h) { \
	_value = h._value; \
	if (_value != NULL) { \
	assert(_value->is_valid(), "obj is valid"); \
	if (h._thread != NULL) { \
	assert(h._thread == Thread::current(), "thread must be current");\
	_thread = h._thread; \
	} else { \
	_thread = Thread::current(); \
	} \
	assert (_thread->is_in_stack((address)this), "not on stack?"); \
	_thread->metadata_handles()->push((Metadata*)_value); \
	} else { \
	_thread = NULL; \
	} \
	} \
	name##Handle& name##Handle::operator=(const name##Handle &s) { \
	remove(); \
	_value = s._value; \
	if (_value != NULL) { \
	assert(_value->is_valid(), "obj is valid"); \
	if (s._thread != NULL) { \
	assert(s._thread == Thread::current(), "thread must be current");\
	_thread = s._thread; \
	} else { \
	_thread = Thread::current(); \
	} \
	assert (_thread->is_in_stack((address)this), "not on stack?"); \
	_thread->metadata_handles()->push((Metadata*)_value); \
	} else { \
	_thread = NULL; \
	} \
	return *this; \
	} \
	inline void name##Handle::remove() { \
	if (_value != NULL) { \
	int i = _thread->metadata_handles()->find_from_end((Metadata*)_value); \
	assert(i!=-1, "not in metadata_handles list"); \
	_thread->metadata_handles()->remove_at(i); \
	} \
	} \
	name##Handle::~name##Handle () { remove(); } \

	DEF_METADATA_HANDLE_FN_NOINLINE(method, Method)
	DEF_METADATA_HANDLE_FN_NOINLINE(constantPool, ConstantPool)


	static uintx chunk_oops_do(OopClosure* f, Chunk* chunk, char* chunk_top) {
	oop* bottom = (oop*) chunk->bottom();
	oop* top = (oop*) chunk_top;
	uintx handles_visited = top - bottom;
	assert(top >= bottom && top <= (oop*) chunk->top(), "just checking");
	// during GC phase 3, a handle may be a forward pointer that
	// is not yet valid, so loosen the assertion
	while (bottom < top) {
	f->do_oop(bottom++);
	}
	return handles_visited;
	}

	// Used for debugging handle allocation.
	NOT_PRODUCT(jint _nof_handlemarks = 0;)

	void HandleArea::oops_do(OopClosure* f) {
	uintx handles_visited = 0;
	// First handle the current chunk. It is filled to the high water mark.
	handles_visited += chunk_oops_do(f, _chunk, _hwm);
	// Then handle all previous chunks. They are completely filled.
	Chunk* k = _first;
	while(k != _chunk) {
	handles_visited += chunk_oops_do(f, k, k->top());
	k = k->next();
	}

	if (_prev != NULL) _prev->oops_do(f);
	}

	void HandleMark::initialize(Thread* thread) {
	_thread = thread;
	// Save area
	_area = thread->handle_area();
	// Save current top
	_chunk = _area->_chunk;
	_hwm = _area->_hwm;
	_max = _area->_max;
	_size_in_bytes = _area->_size_in_bytes;
	debug_only(_area->_handle_mark_nesting++);
	assert(_area->_handle_mark_nesting > 0, "must stack allocate HandleMarks");
	debug_only(Atomic::inc(&_nof_handlemarks);)

	// Link this in the thread
	set_previous_handle_mark(thread->last_handle_mark());
	thread->set_last_handle_mark(this);
	}


	HandleMark::~HandleMark() {
	HandleArea* area = _area; // help compilers with poor alias analysis
	assert(area == _thread->handle_area(), "sanity check");
	assert(area->_handle_mark_nesting > 0, "must stack allocate HandleMarks" );
	debug_only(area->_handle_mark_nesting--);

	// Delete later chunks
	if( _chunk->next() ) {
	// reset arena size before delete chunks. Otherwise, the total
	// arena size could exceed total chunk size
	assert(area->size_in_bytes() > size_in_bytes(), "Sanity check");
	area->set_size_in_bytes(size_in_bytes());
	_chunk->next_chop();
	} else {
	assert(area->size_in_bytes() == size_in_bytes(), "Sanity check");
	}
	// Roll back arena to saved top markers
	area->_chunk = _chunk;
	area->_hwm = _hwm;
	area->_max = _max;
	#ifdef ASSERT
	// clear out first chunk (to detect allocation bugs)
	if (ZapVMHandleArea) {
	memset(_hwm, badHandleValue, _max - _hwm);
	}
	Atomic::dec(&_nof_handlemarks);
	#endif

	// Unlink this from the thread
	_thread->set_last_handle_mark(previous_handle_mark());
	}

	void* HandleMark::operator new(size_t size) throw() {
	return AllocateHeap(size, mtThread);
	}

	void* HandleMark::operator new [] (size_t size) throw() {
	return AllocateHeap(size, mtThread);
	}

	void HandleMark::operator delete(void* p) {
	FreeHeap(p);
	}

	void HandleMark::operator delete[](void* p) {
	FreeHeap(p);
	}

	#ifdef ASSERT

	NoHandleMark::NoHandleMark() {
	HandleArea* area = Thread::current()->handle_area();
	area->_no_handle_mark_nesting++;
	assert(area->_no_handle_mark_nesting > 0, "must stack allocate NoHandleMark" );
	}


	NoHandleMark::~NoHandleMark() {
	HandleArea* area = Thread::current()->handle_area();
	assert(area->_no_handle_mark_nesting > 0, "must stack allocate NoHandleMark" );
	area->_no_handle_mark_nesting--;
	}


	ResetNoHandleMark::ResetNoHandleMark() {
	HandleArea* area = Thread::current()->handle_area();
	_no_handle_mark_nesting = area->_no_handle_mark_nesting;
	area->_no_handle_mark_nesting = 0;
	}


	ResetNoHandleMark::~ResetNoHandleMark() {
	HandleArea* area = Thread::current()->handle_area();
	area->_no_handle_mark_nesting = _no_handle_mark_nesting;
	}

	#endif // ASSERT