hotspot/src/share/vm/gc/g1/heapRegion.inline.hpp - platform/libcore - Git at Google

 /*
  * Copyright (c) 2001, 2015, 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.
  *
  */

 #ifndef SHARE_VM_GC_G1_HEAPREGION_INLINE_HPP
 #define SHARE_VM_GC_G1_HEAPREGION_INLINE_HPP

 #include "gc/g1/g1BlockOffsetTable.inline.hpp"
 #include "gc/g1/g1CollectedHeap.inline.hpp"
 #include "gc/g1/heapRegion.hpp"
 #include "gc/shared/space.hpp"
 #include "oops/oop.inline.hpp"
 #include "runtime/atomic.inline.hpp"

 inline HeapWord* G1OffsetTableContigSpace::allocate_impl(size_t min_word_size,
                                                          size_t desired_word_size,
                                                          size_t* actual_size) {
   HeapWord* obj = top();
   size_t available = pointer_delta(end(), obj);
   size_t want_to_allocate = MIN2(available, desired_word_size);
   if (want_to_allocate >= min_word_size) {
     HeapWord* new_top = obj + want_to_allocate;
     set_top(new_top);
     assert(is_aligned(obj) && is_aligned(new_top), "checking alignment");
     *actual_size = want_to_allocate;
     return obj;
   } else {
     return NULL;
   }
 }

 inline HeapWord* G1OffsetTableContigSpace::par_allocate_impl(size_t min_word_size,
                                                              size_t desired_word_size,
                                                              size_t* actual_size) {
   do {
     HeapWord* obj = top();
     size_t available = pointer_delta(end(), obj);
     size_t want_to_allocate = MIN2(available, desired_word_size);
     if (want_to_allocate >= min_word_size) {
       HeapWord* new_top = obj + want_to_allocate;
       HeapWord* result = (HeapWord*)Atomic::cmpxchg_ptr(new_top, top_addr(), obj);
       // result can be one of two:
       //  the old top value: the exchange succeeded
       //  otherwise: the new value of the top is returned.
       if (result == obj) {
         assert(is_aligned(obj) && is_aligned(new_top), "checking alignment");
         *actual_size = want_to_allocate;
         return obj;
       }
     } else {
       return NULL;
     }
   } while (true);
 }

 inline HeapWord* G1OffsetTableContigSpace::allocate(size_t min_word_size,
                                                     size_t desired_word_size,
                                                     size_t* actual_size) {
   HeapWord* res = allocate_impl(min_word_size, desired_word_size, actual_size);
   if (res != NULL) {
     _offsets.alloc_block(res, *actual_size);
   }
   return res;
 }

 inline HeapWord* G1OffsetTableContigSpace::allocate(size_t word_size) {
   size_t temp;
   return allocate(word_size, word_size, &temp);
 }

 inline HeapWord* G1OffsetTableContigSpace::par_allocate(size_t word_size) {
   size_t temp;
   return par_allocate(word_size, word_size, &temp);
 }

 // Because of the requirement of keeping "_offsets" up to date with the
 // allocations, we sequentialize these with a lock.  Therefore, best if
 // this is used for larger LAB allocations only.
 inline HeapWord* G1OffsetTableContigSpace::par_allocate(size_t min_word_size,
                                                         size_t desired_word_size,
                                                         size_t* actual_size) {
   MutexLocker x(&_par_alloc_lock);
   return allocate(min_word_size, desired_word_size, actual_size);
 }

 inline HeapWord* G1OffsetTableContigSpace::block_start(const void* p) {
   return _offsets.block_start(p);
 }

 inline HeapWord*
 G1OffsetTableContigSpace::block_start_const(const void* p) const {
   return _offsets.block_start_const(p);
 }

 inline bool
 HeapRegion::block_is_obj(const HeapWord* p) const {
   G1CollectedHeap* g1h = G1CollectedHeap::heap();
   if (ClassUnloadingWithConcurrentMark) {
     return !g1h->is_obj_dead(oop(p), this);
   }
   return p < top();
 }

 inline size_t
 HeapRegion::block_size(const HeapWord *addr) const {
   if (addr == top()) {
     return pointer_delta(end(), addr);
   }

   if (block_is_obj(addr)) {
     return oop(addr)->size();
   }

   assert(ClassUnloadingWithConcurrentMark,
          "All blocks should be objects if G1 Class Unloading isn't used. "
          "HR: [" PTR_FORMAT ", " PTR_FORMAT ", " PTR_FORMAT ") "
          "addr: " PTR_FORMAT,
          p2i(bottom()), p2i(top()), p2i(end()), p2i(addr));

   // Old regions' dead objects may have dead classes
   // We need to find the next live object in some other
   // manner than getting the oop size
   G1CollectedHeap* g1h = G1CollectedHeap::heap();
   HeapWord* next = g1h->concurrent_mark()->prevMarkBitMap()->
       getNextMarkedWordAddress(addr, prev_top_at_mark_start());

   assert(next > addr, "must get the next live object");
   return pointer_delta(next, addr);
 }

 inline HeapWord* HeapRegion::par_allocate_no_bot_updates(size_t min_word_size,
                                                          size_t desired_word_size,
                                                          size_t* actual_word_size) {
   assert(is_young(), "we can only skip BOT updates on young regions");
   return par_allocate_impl(min_word_size, desired_word_size, actual_word_size);
 }

 inline HeapWord* HeapRegion::allocate_no_bot_updates(size_t word_size) {
   size_t temp;
   return allocate_no_bot_updates(word_size, word_size, &temp);
 }

 inline HeapWord* HeapRegion::allocate_no_bot_updates(size_t min_word_size,
                                                      size_t desired_word_size,
                                                      size_t* actual_word_size) {
   assert(is_young(), "we can only skip BOT updates on young regions");
   return allocate_impl(min_word_size, desired_word_size, actual_word_size);
 }

 inline void HeapRegion::note_start_of_marking() {
   _next_marked_bytes = 0;
   _next_top_at_mark_start = top();
 }

 inline void HeapRegion::note_end_of_marking() {
   _prev_top_at_mark_start = _next_top_at_mark_start;
   _prev_marked_bytes = _next_marked_bytes;
   _next_marked_bytes = 0;

   assert(_prev_marked_bytes <=
          (size_t) pointer_delta(prev_top_at_mark_start(), bottom()) *
          HeapWordSize, "invariant");
 }

 inline void HeapRegion::note_start_of_copying(bool during_initial_mark) {
   if (is_survivor()) {
     // This is how we always allocate survivors.
     assert(_next_top_at_mark_start == bottom(), "invariant");
   } else {
     if (during_initial_mark) {
       // During initial-mark we'll explicitly mark any objects on old
       // regions that are pointed to by roots. Given that explicit
       // marks only make sense under NTAMS it'd be nice if we could
       // check that condition if we wanted to. Given that we don't
       // know where the top of this region will end up, we simply set
       // NTAMS to the end of the region so all marks will be below
       // NTAMS. We'll set it to the actual top when we retire this region.
       _next_top_at_mark_start = end();
     } else {
       // We could have re-used this old region as to-space over a
       // couple of GCs since the start of the concurrent marking
       // cycle. This means that [bottom,NTAMS) will contain objects
       // copied up to and including initial-mark and [NTAMS, top)
       // will contain objects copied during the concurrent marking cycle.
       assert(top() >= _next_top_at_mark_start, "invariant");
     }
   }
 }

 inline void HeapRegion::note_end_of_copying(bool during_initial_mark) {
   if (is_survivor()) {
     // This is how we always allocate survivors.
     assert(_next_top_at_mark_start == bottom(), "invariant");
   } else {
     if (during_initial_mark) {
       // See the comment for note_start_of_copying() for the details
       // on this.
       assert(_next_top_at_mark_start == end(), "pre-condition");
       _next_top_at_mark_start = top();
     } else {
       // See the comment for note_start_of_copying() for the details
       // on this.
       assert(top() >= _next_top_at_mark_start, "invariant");
     }
   }
 }

 inline bool HeapRegion::in_collection_set() const {
   return G1CollectedHeap::heap()->is_in_cset(this);
 }

 inline HeapRegion* HeapRegion::next_in_collection_set() const {
   assert(in_collection_set(), "should only invoke on member of CS.");
   assert(_next_in_special_set == NULL ||
          _next_in_special_set->in_collection_set(),
          "Malformed CS.");
   return _next_in_special_set;
 }

 void HeapRegion::set_next_in_collection_set(HeapRegion* r) {
   assert(in_collection_set(), "should only invoke on member of CS.");
   assert(r == NULL || r->in_collection_set(), "Malformed CS.");
   _next_in_special_set = r;
 }

 #endif // SHARE_VM_GC_G1_HEAPREGION_INLINE_HPP
	/*
	* Copyright (c) 2001, 2015, 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.
	*
	*/

	#ifndef SHARE_VM_GC_G1_HEAPREGION_INLINE_HPP
	#define SHARE_VM_GC_G1_HEAPREGION_INLINE_HPP

	#include "gc/g1/g1BlockOffsetTable.inline.hpp"
	#include "gc/g1/g1CollectedHeap.inline.hpp"
	#include "gc/g1/heapRegion.hpp"
	#include "gc/shared/space.hpp"
	#include "oops/oop.inline.hpp"
	#include "runtime/atomic.inline.hpp"

	inline HeapWord* G1OffsetTableContigSpace::allocate_impl(size_t min_word_size,
	size_t desired_word_size,
	size_t* actual_size) {
	HeapWord* obj = top();
	size_t available = pointer_delta(end(), obj);
	size_t want_to_allocate = MIN2(available, desired_word_size);
	if (want_to_allocate >= min_word_size) {
	HeapWord* new_top = obj + want_to_allocate;
	set_top(new_top);
	assert(is_aligned(obj) && is_aligned(new_top), "checking alignment");
	*actual_size = want_to_allocate;
	return obj;
	} else {
	return NULL;
	}
	}

	inline HeapWord* G1OffsetTableContigSpace::par_allocate_impl(size_t min_word_size,
	size_t desired_word_size,
	size_t* actual_size) {
	do {
	HeapWord* obj = top();
	size_t available = pointer_delta(end(), obj);
	size_t want_to_allocate = MIN2(available, desired_word_size);
	if (want_to_allocate >= min_word_size) {
	HeapWord* new_top = obj + want_to_allocate;
	HeapWord* result = (HeapWord*)Atomic::cmpxchg_ptr(new_top, top_addr(), obj);
	// result can be one of two:
	// the old top value: the exchange succeeded
	// otherwise: the new value of the top is returned.
	if (result == obj) {
	assert(is_aligned(obj) && is_aligned(new_top), "checking alignment");
	*actual_size = want_to_allocate;
	return obj;
	}
	} else {
	return NULL;
	}
	} while (true);
	}

	inline HeapWord* G1OffsetTableContigSpace::allocate(size_t min_word_size,
	size_t desired_word_size,
	size_t* actual_size) {
	HeapWord* res = allocate_impl(min_word_size, desired_word_size, actual_size);
	if (res != NULL) {
	_offsets.alloc_block(res, *actual_size);
	}
	return res;
	}

	inline HeapWord* G1OffsetTableContigSpace::allocate(size_t word_size) {
	size_t temp;
	return allocate(word_size, word_size, &temp);
	}

	inline HeapWord* G1OffsetTableContigSpace::par_allocate(size_t word_size) {
	size_t temp;
	return par_allocate(word_size, word_size, &temp);
	}

	// Because of the requirement of keeping "_offsets" up to date with the
	// allocations, we sequentialize these with a lock. Therefore, best if
	// this is used for larger LAB allocations only.
	inline HeapWord* G1OffsetTableContigSpace::par_allocate(size_t min_word_size,
	size_t desired_word_size,
	size_t* actual_size) {
	MutexLocker x(&_par_alloc_lock);
	return allocate(min_word_size, desired_word_size, actual_size);
	}

	inline HeapWord* G1OffsetTableContigSpace::block_start(const void* p) {
	return _offsets.block_start(p);
	}

	inline HeapWord*
	G1OffsetTableContigSpace::block_start_const(const void* p) const {
	return _offsets.block_start_const(p);
	}

	inline bool
	HeapRegion::block_is_obj(const HeapWord* p) const {
	G1CollectedHeap* g1h = G1CollectedHeap::heap();
	if (ClassUnloadingWithConcurrentMark) {
	return !g1h->is_obj_dead(oop(p), this);
	}
	return p < top();
	}

	inline size_t
	HeapRegion::block_size(const HeapWord *addr) const {
	if (addr == top()) {
	return pointer_delta(end(), addr);
	}

	if (block_is_obj(addr)) {
	return oop(addr)->size();
	}

	assert(ClassUnloadingWithConcurrentMark,
	"All blocks should be objects if G1 Class Unloading isn't used. "
	"HR: [" PTR_FORMAT ", " PTR_FORMAT ", " PTR_FORMAT ") "
	"addr: " PTR_FORMAT,
	p2i(bottom()), p2i(top()), p2i(end()), p2i(addr));

	// Old regions' dead objects may have dead classes
	// We need to find the next live object in some other
	// manner than getting the oop size
	G1CollectedHeap* g1h = G1CollectedHeap::heap();
	HeapWord* next = g1h->concurrent_mark()->prevMarkBitMap()->
	getNextMarkedWordAddress(addr, prev_top_at_mark_start());

	assert(next > addr, "must get the next live object");
	return pointer_delta(next, addr);
	}

	inline HeapWord* HeapRegion::par_allocate_no_bot_updates(size_t min_word_size,
	size_t desired_word_size,
	size_t* actual_word_size) {
	assert(is_young(), "we can only skip BOT updates on young regions");
	return par_allocate_impl(min_word_size, desired_word_size, actual_word_size);
	}

	inline HeapWord* HeapRegion::allocate_no_bot_updates(size_t word_size) {
	size_t temp;
	return allocate_no_bot_updates(word_size, word_size, &temp);
	}

	inline HeapWord* HeapRegion::allocate_no_bot_updates(size_t min_word_size,
	size_t desired_word_size,
	size_t* actual_word_size) {
	assert(is_young(), "we can only skip BOT updates on young regions");
	return allocate_impl(min_word_size, desired_word_size, actual_word_size);
	}

	inline void HeapRegion::note_start_of_marking() {
	_next_marked_bytes = 0;
	_next_top_at_mark_start = top();
	}

	inline void HeapRegion::note_end_of_marking() {
	_prev_top_at_mark_start = _next_top_at_mark_start;
	_prev_marked_bytes = _next_marked_bytes;
	_next_marked_bytes = 0;

	assert(_prev_marked_bytes <=
	(size_t) pointer_delta(prev_top_at_mark_start(), bottom()) *
	HeapWordSize, "invariant");
	}

	inline void HeapRegion::note_start_of_copying(bool during_initial_mark) {
	if (is_survivor()) {
	// This is how we always allocate survivors.
	assert(_next_top_at_mark_start == bottom(), "invariant");
	} else {
	if (during_initial_mark) {
	// During initial-mark we'll explicitly mark any objects on old
	// regions that are pointed to by roots. Given that explicit
	// marks only make sense under NTAMS it'd be nice if we could
	// check that condition if we wanted to. Given that we don't
	// know where the top of this region will end up, we simply set
	// NTAMS to the end of the region so all marks will be below
	// NTAMS. We'll set it to the actual top when we retire this region.
	_next_top_at_mark_start = end();
	} else {
	// We could have re-used this old region as to-space over a
	// couple of GCs since the start of the concurrent marking
	// cycle. This means that [bottom,NTAMS) will contain objects
	// copied up to and including initial-mark and [NTAMS, top)
	// will contain objects copied during the concurrent marking cycle.
	assert(top() >= _next_top_at_mark_start, "invariant");
	}
	}
	}

	inline void HeapRegion::note_end_of_copying(bool during_initial_mark) {
	if (is_survivor()) {
	// This is how we always allocate survivors.
	assert(_next_top_at_mark_start == bottom(), "invariant");
	} else {
	if (during_initial_mark) {
	// See the comment for note_start_of_copying() for the details
	// on this.
	assert(_next_top_at_mark_start == end(), "pre-condition");
	_next_top_at_mark_start = top();
	} else {
	// See the comment for note_start_of_copying() for the details
	// on this.
	assert(top() >= _next_top_at_mark_start, "invariant");
	}
	}
	}

	inline bool HeapRegion::in_collection_set() const {
	return G1CollectedHeap::heap()->is_in_cset(this);
	}

	inline HeapRegion* HeapRegion::next_in_collection_set() const {
	assert(in_collection_set(), "should only invoke on member of CS.");
	assert(_next_in_special_set == NULL \|\|
	_next_in_special_set->in_collection_set(),
	"Malformed CS.");
	return _next_in_special_set;
	}

	void HeapRegion::set_next_in_collection_set(HeapRegion* r) {
	assert(in_collection_set(), "should only invoke on member of CS.");
	assert(r == NULL \|\| r->in_collection_set(), "Malformed CS.");
	_next_in_special_set = r;
	}

	#endif // SHARE_VM_GC_G1_HEAPREGION_INLINE_HPP