1 /* 2 * Copyright (c) 2000, 2010, 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_VM_MEMORY_PERMGEN_HPP 26 #define SHARE_VM_MEMORY_PERMGEN_HPP 27 28 #include "gc_interface/gcCause.hpp" 29 #include "memory/generation.hpp" 30 #include "memory/iterator.hpp" 31 #include "runtime/handles.hpp" 32 #include "runtime/mutexLocker.hpp" 33 #include "runtime/virtualspace.hpp" 34 35 // All heaps contains a "permanent generation," containing permanent 36 // (reflective) objects. This is like a regular generation in some ways, 37 // but unlike one in others, and so is split apart. 38 39 class Generation; 40 class GenRemSet; 41 class CSpaceCounters; 42 43 // PermGen models the part of the heap used to allocate class meta-data. 44 45 class PermGen : public CHeapObj { 46 friend class VMStructs; 47 protected: 48 size_t _capacity_expansion_limit; // maximum expansion allowed without a 49 // full gc occurring 50 void set_capacity_expansion_limit(size_t limit) { 51 assert_locked_or_safepoint(Heap_lock); 52 _capacity_expansion_limit = limit; 53 } 54 55 HeapWord* mem_allocate_in_gen(size_t size, Generation* gen); 56 // Along with mem_allocate_in_gen() above, implements policy for 57 // "scheduling" allocation/expansion/collection of the perm gen. 58 // The virtual method request_...() below can be overridden by 59 // subtypes that want to implement a different expansion/collection 60 // policy from the default provided. 61 virtual HeapWord* request_expand_and_allocate(Generation* gen, size_t size, 62 GCCause::Cause prev_cause); 63 64 public: 65 enum Name { 66 MarkSweepCompact, MarkSweep, ConcurrentMarkSweep 67 }; 68 69 // Permanent allocation (initialized) 70 virtual HeapWord* mem_allocate(size_t size) = 0; 71 72 // Mark sweep support 73 virtual void compute_new_size() = 0; 74 75 // Ideally, we would use MI (IMHO) but we'll do delegation instead. 76 virtual Generation* as_gen() const = 0; 77 78 virtual void oop_iterate(OopClosure* cl) { 79 Generation* g = as_gen(); 80 assert(g != NULL, "as_gen() NULL"); 81 g->oop_iterate(cl); 82 } 83 84 virtual void object_iterate(ObjectClosure* cl) { 85 Generation* g = as_gen(); 86 assert(g != NULL, "as_gen() NULL"); 87 g->object_iterate(cl); 88 } 89 90 // Performance Counter support 91 virtual void update_counters() { 92 Generation* g = as_gen(); 93 assert(g != NULL, "as_gen() NULL"); 94 g->update_counters(); 95 } 96 }; 97 98 #endif // SHARE_VM_MEMORY_PERMGEN_HPP