1 /* 2 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_GC_SHARED_MEM_ALLOCATOR_HPP 26 #define SHARE_GC_SHARED_MEM_ALLOCATOR_HPP 27 28 #include "gc/shared/collectedHeap.hpp" 29 #include "memory/memRegion.hpp" 30 #include "oops/oopsHierarchy.hpp" 31 #include "utilities/exceptions.hpp" 32 #include "utilities/macros.hpp" 33 34 // These fascilities are used for allocating, and initializing newly allocated objects. 35 36 class MemAllocator: StackObj { 37 class Allocation; 38 39 protected: 40 CollectedHeap* const _heap; 41 Thread* const _thread; 42 Klass* const _klass; 43 const size_t _word_size; 44 45 private: 46 // Allocate from the current thread's TLAB, with broken-out slow path. 47 HeapWord* allocate_inside_tlab(Allocation& allocation) const; 48 HeapWord* allocate_inside_tlab_slow(Allocation& allocation) const; 49 HeapWord* allocate_outside_tlab(Allocation& allocation) const; 50 51 protected: MemAllocator(Klass * klass,size_t word_size,Thread * thread)52 MemAllocator(Klass* klass, size_t word_size, Thread* thread) 53 : _heap(Universe::heap()), 54 _thread(thread), 55 _klass(klass), 56 _word_size(word_size) 57 { } 58 59 // This function clears the memory of the object 60 void mem_clear(HeapWord* mem) const; 61 // This finish constructing an oop by installing the mark word and the Klass* pointer 62 // last. At the point when the Klass pointer is initialized, this is a constructed object 63 // that must be parseable as an oop by concurrent collectors. 64 oop finish(HeapWord* mem) const; 65 66 // Raw memory allocation. This may or may not use TLAB allocations to satisfy the 67 // allocation. A GC implementation may override this function to satisfy the allocation 68 // in any way. But the default is to try a TLAB allocation, and otherwise perform 69 // mem_allocate. 70 virtual HeapWord* mem_allocate(Allocation& allocation) const; 71 obj_memory_range(oop obj) const72 virtual MemRegion obj_memory_range(oop obj) const { 73 return MemRegion((HeapWord*)obj, _word_size); 74 } 75 76 public: 77 oop allocate() const; 78 virtual oop initialize(HeapWord* mem) const = 0; 79 }; 80 81 class ObjAllocator: public MemAllocator { 82 public: ObjAllocator(Klass * klass,size_t word_size,Thread * thread=Thread::current ())83 ObjAllocator(Klass* klass, size_t word_size, Thread* thread = Thread::current()) 84 : MemAllocator(klass, word_size, thread) {} 85 virtual oop initialize(HeapWord* mem) const; 86 }; 87 88 class ObjArrayAllocator: public MemAllocator { 89 const int _length; 90 const bool _do_zero; 91 protected: 92 virtual MemRegion obj_memory_range(oop obj) const; 93 94 public: ObjArrayAllocator(Klass * klass,size_t word_size,int length,bool do_zero,Thread * thread=Thread::current ())95 ObjArrayAllocator(Klass* klass, size_t word_size, int length, bool do_zero, 96 Thread* thread = Thread::current()) 97 : MemAllocator(klass, word_size, thread), 98 _length(length), 99 _do_zero(do_zero) {} 100 virtual oop initialize(HeapWord* mem) const; 101 }; 102 103 class ClassAllocator: public MemAllocator { 104 public: ClassAllocator(Klass * klass,size_t word_size,Thread * thread=Thread::current ())105 ClassAllocator(Klass* klass, size_t word_size, Thread* thread = Thread::current()) 106 : MemAllocator(klass, word_size, thread) {} 107 virtual oop initialize(HeapWord* mem) const; 108 }; 109 110 #endif // SHARE_GC_SHARED_MEM_ALLOCATOR_HPP 111