Sat, 08 Oct 2016 09:31:28 -0400
The parallel GC mark-phase should be MT-safe for 3A2000.
1 /*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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13 * accompanied this code).
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23 */
25 #include "precompiled.hpp"
26 #include "gc_implementation/parallelScavenge/parMarkBitMap.hpp"
27 #include "gc_implementation/parallelScavenge/psParallelCompact.hpp"
28 #include "oops/oop.inline.hpp"
29 #include "runtime/os.hpp"
30 #include "utilities/bitMap.inline.hpp"
31 #include "services/memTracker.hpp"
32 #ifdef TARGET_OS_FAMILY_linux
33 # include "os_linux.inline.hpp"
34 #endif
35 #ifdef TARGET_OS_FAMILY_solaris
36 # include "os_solaris.inline.hpp"
37 #endif
38 #ifdef TARGET_OS_FAMILY_windows
39 # include "os_windows.inline.hpp"
40 #endif
41 #ifdef TARGET_OS_FAMILY_aix
42 # include "os_aix.inline.hpp"
43 #endif
44 #ifdef TARGET_OS_FAMILY_bsd
45 # include "os_bsd.inline.hpp"
46 #endif
48 bool
49 ParMarkBitMap::initialize(MemRegion covered_region)
50 {
51 const idx_t bits = bits_required(covered_region);
52 // The bits will be divided evenly between two bitmaps; each of them should be
53 // an integral number of words.
54 assert(bits % (BitsPerWord * 2) == 0, "region size unaligned");
56 const size_t words = bits / BitsPerWord;
57 const size_t raw_bytes = words * sizeof(idx_t);
58 const size_t page_sz = os::page_size_for_region(raw_bytes, raw_bytes, 10);
59 const size_t granularity = os::vm_allocation_granularity();
60 _reserved_byte_size = align_size_up(raw_bytes, MAX2(page_sz, granularity));
62 const size_t rs_align = page_sz == (size_t) os::vm_page_size() ? 0 :
63 MAX2(page_sz, granularity);
64 ReservedSpace rs(_reserved_byte_size, rs_align, rs_align > 0);
65 os::trace_page_sizes("par bitmap", raw_bytes, raw_bytes, page_sz,
66 rs.base(), rs.size());
68 MemTracker::record_virtual_memory_type((address)rs.base(), mtGC);
70 _virtual_space = new PSVirtualSpace(rs, page_sz);
71 if (_virtual_space != NULL && _virtual_space->expand_by(_reserved_byte_size)) {
72 _region_start = covered_region.start();
73 _region_size = covered_region.word_size();
74 idx_t* map = (idx_t*)_virtual_space->reserved_low_addr();
75 _beg_bits.set_map(map);
76 _beg_bits.set_size(bits / 2);
77 _end_bits.set_map(map + words / 2);
78 _end_bits.set_size(bits / 2);
79 return true;
80 }
82 _region_start = 0;
83 _region_size = 0;
84 if (_virtual_space != NULL) {
85 delete _virtual_space;
86 _virtual_space = NULL;
87 // Release memory reserved in the space.
88 rs.release();
89 }
90 return false;
91 }
93 #ifdef ASSERT
94 extern size_t mark_bitmap_count;
95 extern size_t mark_bitmap_size;
96 #endif // #ifdef ASSERT
98 bool
99 ParMarkBitMap::mark_obj(HeapWord* addr, size_t size)
100 {
101 const idx_t beg_bit = addr_to_bit(addr);
102 if (_beg_bits.par_set_bit(beg_bit)) {
103 const idx_t end_bit = addr_to_bit(addr + size - 1);
104 bool end_bit_ok = _end_bits.par_set_bit(end_bit);
105 assert(end_bit_ok, "concurrency problem");
106 DEBUG_ONLY(Atomic::inc_ptr(&mark_bitmap_count));
107 DEBUG_ONLY(Atomic::add_ptr(size, &mark_bitmap_size));
108 #ifdef MIPS64
109 if (Use3A2000) OrderAccess::fence();
110 #endif
111 return true;
112 }
113 return false;
114 }
116 size_t ParMarkBitMap::live_words_in_range(HeapWord* beg_addr, oop end_obj) const
117 {
118 assert(beg_addr <= (HeapWord*)end_obj, "bad range");
119 assert(is_marked(end_obj), "end_obj must be live");
121 idx_t live_bits = 0;
123 // The bitmap routines require the right boundary to be word-aligned.
124 const idx_t end_bit = addr_to_bit((HeapWord*)end_obj);
125 const idx_t range_end = BitMap::word_align_up(end_bit);
127 idx_t beg_bit = find_obj_beg(addr_to_bit(beg_addr), range_end);
128 while (beg_bit < end_bit) {
129 idx_t tmp_end = find_obj_end(beg_bit, range_end);
130 assert(tmp_end < end_bit, "missing end bit");
131 live_bits += tmp_end - beg_bit + 1;
132 beg_bit = find_obj_beg(tmp_end + 1, range_end);
133 }
134 return bits_to_words(live_bits);
135 }
137 ParMarkBitMap::IterationStatus
138 ParMarkBitMap::iterate(ParMarkBitMapClosure* live_closure,
139 idx_t range_beg, idx_t range_end) const
140 {
141 DEBUG_ONLY(verify_bit(range_beg);)
142 DEBUG_ONLY(verify_bit(range_end);)
143 assert(range_beg <= range_end, "live range invalid");
145 // The bitmap routines require the right boundary to be word-aligned.
146 const idx_t search_end = BitMap::word_align_up(range_end);
148 idx_t cur_beg = find_obj_beg(range_beg, search_end);
149 while (cur_beg < range_end) {
150 const idx_t cur_end = find_obj_end(cur_beg, search_end);
151 if (cur_end >= range_end) {
152 // The obj ends outside the range.
153 live_closure->set_source(bit_to_addr(cur_beg));
154 return incomplete;
155 }
157 const size_t size = obj_size(cur_beg, cur_end);
158 IterationStatus status = live_closure->do_addr(bit_to_addr(cur_beg), size);
159 if (status != incomplete) {
160 assert(status == would_overflow || status == full, "sanity");
161 return status;
162 }
164 // Successfully processed the object; look for the next object.
165 cur_beg = find_obj_beg(cur_end + 1, search_end);
166 }
168 live_closure->set_source(bit_to_addr(range_end));
169 return complete;
170 }
172 ParMarkBitMap::IterationStatus
173 ParMarkBitMap::iterate(ParMarkBitMapClosure* live_closure,
174 ParMarkBitMapClosure* dead_closure,
175 idx_t range_beg, idx_t range_end,
176 idx_t dead_range_end) const
177 {
178 DEBUG_ONLY(verify_bit(range_beg);)
179 DEBUG_ONLY(verify_bit(range_end);)
180 DEBUG_ONLY(verify_bit(dead_range_end);)
181 assert(range_beg <= range_end, "live range invalid");
182 assert(range_end <= dead_range_end, "dead range invalid");
184 // The bitmap routines require the right boundary to be word-aligned.
185 const idx_t live_search_end = BitMap::word_align_up(range_end);
186 const idx_t dead_search_end = BitMap::word_align_up(dead_range_end);
188 idx_t cur_beg = range_beg;
189 if (range_beg < range_end && is_unmarked(range_beg)) {
190 // The range starts with dead space. Look for the next object, then fill.
191 cur_beg = find_obj_beg(range_beg + 1, dead_search_end);
192 const idx_t dead_space_end = MIN2(cur_beg - 1, dead_range_end - 1);
193 const size_t size = obj_size(range_beg, dead_space_end);
194 dead_closure->do_addr(bit_to_addr(range_beg), size);
195 }
197 while (cur_beg < range_end) {
198 const idx_t cur_end = find_obj_end(cur_beg, live_search_end);
199 if (cur_end >= range_end) {
200 // The obj ends outside the range.
201 live_closure->set_source(bit_to_addr(cur_beg));
202 return incomplete;
203 }
205 const size_t size = obj_size(cur_beg, cur_end);
206 IterationStatus status = live_closure->do_addr(bit_to_addr(cur_beg), size);
207 if (status != incomplete) {
208 assert(status == would_overflow || status == full, "sanity");
209 return status;
210 }
212 // Look for the start of the next object.
213 const idx_t dead_space_beg = cur_end + 1;
214 cur_beg = find_obj_beg(dead_space_beg, dead_search_end);
215 if (cur_beg > dead_space_beg) {
216 // Found dead space; compute the size and invoke the dead closure.
217 const idx_t dead_space_end = MIN2(cur_beg - 1, dead_range_end - 1);
218 const size_t size = obj_size(dead_space_beg, dead_space_end);
219 dead_closure->do_addr(bit_to_addr(dead_space_beg), size);
220 }
221 }
223 live_closure->set_source(bit_to_addr(range_end));
224 return complete;
225 }
227 #ifdef ASSERT
228 void ParMarkBitMap::verify_clear() const
229 {
230 const idx_t* const beg = (const idx_t*)_virtual_space->committed_low_addr();
231 const idx_t* const end = (const idx_t*)_virtual_space->committed_high_addr();
232 for (const idx_t* p = beg; p < end; ++p) {
233 assert(*p == 0, "bitmap not clear");
234 }
235 }
236 #endif // #ifdef ASSERT