1 /* 2 * Copyright (c) 2013, 2018, Red Hat, Inc. All rights reserved. 3 * 4 * This code is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License version 2 only, as 6 * published by the Free Software Foundation. 7 * 8 * This code is distributed in the hope that it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 11 * version 2 for more details (a copy is included in the LICENSE file that 12 * accompanied this code). 13 * 14 * You should have received a copy of the GNU General Public License version 15 * 2 along with this work; if not, write to the Free Software Foundation, 16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 17 * 18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 19 * or visit www.oracle.com if you need additional information or have any 20 * questions. 21 * 22 */ 23 24 #ifndef SHARE_VM_GC_SHENANDOAH_SHENANDOAHHEAPREGIONSET_HPP 25 #define SHARE_VM_GC_SHENANDOAH_SHENANDOAHHEAPREGIONSET_HPP 26 27 #include "memory/allocation.hpp" 28 #include "gc/shenandoah/shenandoahHeap.hpp" 29 #include "gc/shenandoah/shenandoahHeapRegion.hpp" 30 31 class ShenandoahHeapRegionSet; 32 33 class ShenandoahHeapRegionSetIterator : public StackObj { 34 private: 35 const ShenandoahHeapRegionSet* _set; 36 ShenandoahHeap* const _heap; 37 38 DEFINE_PAD_MINUS_SIZE(0, DEFAULT_CACHE_LINE_SIZE, sizeof(volatile jint)); 39 volatile jint _current_index; 40 DEFINE_PAD_MINUS_SIZE(1, DEFAULT_CACHE_LINE_SIZE, 0); 41 42 // No implicit copying: iterators should be passed by reference to capture the state 43 ShenandoahHeapRegionSetIterator(const ShenandoahHeapRegionSetIterator& that); 44 ShenandoahHeapRegionSetIterator& operator=(const ShenandoahHeapRegionSetIterator& o); 45 46 public: 47 ShenandoahHeapRegionSetIterator(const ShenandoahHeapRegionSet* const set); 48 49 // Reset existing iterator to new set 50 void reset(const ShenandoahHeapRegionSet* const set); 51 52 // MT version 53 ShenandoahHeapRegion* claim_next(); 54 55 // Single-thread version 56 ShenandoahHeapRegion* next(); 57 }; 58 59 class ShenandoahHeapRegionSet : public CHeapObj<mtGC> { 60 friend class ShenandoahHeap; 61 private: 62 ShenandoahHeap* const _heap; 63 size_t const _map_size; 64 size_t const _region_size_bytes_shift; 65 jbyte* const _set_map; 66 // Bias set map's base address for fast test if an oop is in set 67 jbyte* const _biased_set_map; 68 size_t _region_count; 69 70 public: 71 ShenandoahHeapRegionSet(); 72 ~ShenandoahHeapRegionSet(); 73 74 // Add region to set 75 void add_region(ShenandoahHeapRegion* r); 76 bool add_region_check_for_duplicates(ShenandoahHeapRegion* r); 77 78 // Remove region from set 79 void remove_region(ShenandoahHeapRegion* r); 80 81 size_t count() const { return _region_count; } 82 bool is_empty() const { return _region_count == 0; } 83 84 inline bool is_in(ShenandoahHeapRegion* r) const; 85 inline bool is_in(size_t region_number) const; 86 inline bool is_in(HeapWord* p) const; 87 88 void print_on(outputStream* out) const; 89 90 void clear(); 91 92 private: 93 jbyte* biased_map_address() const { 94 return _biased_set_map; 95 } 96 }; 97 98 #endif //SHARE_VM_GC_SHENANDOAH_SHENANDOAHHEAPREGIONSET_HPP