Mon, 21 Jul 2014 09:59:46 +0200
8048085: Aborting marking just before remark results in useless additional clearing of the next mark bitmap
Summary: Skip clearing the next bitmap if we just recently aborted since the full GC already clears this bitmap.
Reviewed-by: brutisso
ysr@777 | 1 | /* |
drchase@6680 | 2 | * Copyright (c) 2001, 2014, Oracle and/or its affiliates. All rights reserved. |
ysr@777 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
ysr@777 | 4 | * |
ysr@777 | 5 | * This code is free software; you can redistribute it and/or modify it |
ysr@777 | 6 | * under the terms of the GNU General Public License version 2 only, as |
ysr@777 | 7 | * published by the Free Software Foundation. |
ysr@777 | 8 | * |
ysr@777 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
ysr@777 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
ysr@777 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
ysr@777 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
ysr@777 | 13 | * accompanied this code). |
ysr@777 | 14 | * |
ysr@777 | 15 | * You should have received a copy of the GNU General Public License version |
ysr@777 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
ysr@777 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
ysr@777 | 18 | * |
trims@1907 | 19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
trims@1907 | 20 | * or visit www.oracle.com if you need additional information or have any |
trims@1907 | 21 | * questions. |
ysr@777 | 22 | * |
ysr@777 | 23 | */ |
ysr@777 | 24 | |
stefank@2314 | 25 | #include "precompiled.hpp" |
tonyp@2963 | 26 | #include "gc_implementation/g1/heapRegion.hpp" |
tonyp@2963 | 27 | #include "gc_implementation/g1/heapRegionSeq.inline.hpp" |
brutisso@6385 | 28 | #include "gc_implementation/g1/heapRegionSet.hpp" |
stefank@2314 | 29 | #include "gc_implementation/g1/g1CollectedHeap.inline.hpp" |
stefank@2314 | 30 | #include "memory/allocation.hpp" |
ysr@777 | 31 | |
tonyp@2963 | 32 | // Private |
ysr@777 | 33 | |
tonyp@3713 | 34 | uint HeapRegionSeq::find_contiguous_from(uint from, uint num) { |
tonyp@3713 | 35 | uint len = length(); |
tonyp@2963 | 36 | assert(num > 1, "use this only for sequences of length 2 or greater"); |
tonyp@2963 | 37 | assert(from <= len, |
tonyp@3713 | 38 | err_msg("from: %u should be valid and <= than %u", from, len)); |
ysr@777 | 39 | |
tonyp@3713 | 40 | uint curr = from; |
tonyp@3713 | 41 | uint first = G1_NULL_HRS_INDEX; |
tonyp@3713 | 42 | uint num_so_far = 0; |
tonyp@2963 | 43 | while (curr < len && num_so_far < num) { |
tonyp@2963 | 44 | if (at(curr)->is_empty()) { |
tonyp@2963 | 45 | if (first == G1_NULL_HRS_INDEX) { |
tonyp@2472 | 46 | first = curr; |
tonyp@2472 | 47 | num_so_far = 1; |
tonyp@2472 | 48 | } else { |
tonyp@2472 | 49 | num_so_far += 1; |
tonyp@2472 | 50 | } |
tonyp@2472 | 51 | } else { |
tonyp@2963 | 52 | first = G1_NULL_HRS_INDEX; |
tonyp@2472 | 53 | num_so_far = 0; |
tonyp@2472 | 54 | } |
tonyp@2472 | 55 | curr += 1; |
tonyp@2472 | 56 | } |
tonyp@2472 | 57 | assert(num_so_far <= num, "post-condition"); |
tonyp@2472 | 58 | if (num_so_far == num) { |
tonyp@2643 | 59 | // we found enough space for the humongous object |
tonyp@2963 | 60 | assert(from <= first && first < len, "post-condition"); |
tonyp@2963 | 61 | assert(first < curr && (curr - first) == num, "post-condition"); |
tonyp@3713 | 62 | for (uint i = first; i < first + num; ++i) { |
tonyp@2963 | 63 | assert(at(i)->is_empty(), "post-condition"); |
tonyp@2472 | 64 | } |
tonyp@2472 | 65 | return first; |
tonyp@2472 | 66 | } else { |
tonyp@2472 | 67 | // we failed to find enough space for the humongous object |
tonyp@2963 | 68 | return G1_NULL_HRS_INDEX; |
tonyp@2472 | 69 | } |
tonyp@2472 | 70 | } |
tonyp@2472 | 71 | |
tonyp@2963 | 72 | // Public |
tonyp@2472 | 73 | |
tschatzl@5773 | 74 | void HeapRegionSeq::initialize(HeapWord* bottom, HeapWord* end) { |
tonyp@3713 | 75 | assert((uintptr_t) bottom % HeapRegion::GrainBytes == 0, |
tonyp@2963 | 76 | "bottom should be heap region aligned"); |
tonyp@3713 | 77 | assert((uintptr_t) end % HeapRegion::GrainBytes == 0, |
tonyp@2963 | 78 | "end should be heap region aligned"); |
tonyp@2963 | 79 | |
tonyp@2963 | 80 | _next_search_index = 0; |
tonyp@2963 | 81 | _allocated_length = 0; |
tonyp@2963 | 82 | |
tschatzl@5773 | 83 | _regions.initialize(bottom, end, HeapRegion::GrainBytes); |
tonyp@2963 | 84 | } |
tonyp@2963 | 85 | |
tonyp@2963 | 86 | MemRegion HeapRegionSeq::expand_by(HeapWord* old_end, |
tonyp@2963 | 87 | HeapWord* new_end, |
tonyp@2963 | 88 | FreeRegionList* list) { |
tonyp@2963 | 89 | assert(old_end < new_end, "don't call it otherwise"); |
tonyp@2963 | 90 | G1CollectedHeap* g1h = G1CollectedHeap::heap(); |
tonyp@2963 | 91 | |
tonyp@2963 | 92 | HeapWord* next_bottom = old_end; |
tschatzl@5773 | 93 | assert(heap_bottom() <= next_bottom, "invariant"); |
tonyp@2963 | 94 | while (next_bottom < new_end) { |
tschatzl@5773 | 95 | assert(next_bottom < heap_end(), "invariant"); |
tonyp@3713 | 96 | uint index = length(); |
tonyp@2963 | 97 | |
tschatzl@5773 | 98 | assert(index < max_length(), "otherwise we cannot expand further"); |
tonyp@2963 | 99 | if (index == 0) { |
tonyp@2963 | 100 | // We have not allocated any regions so far |
tschatzl@5773 | 101 | assert(next_bottom == heap_bottom(), "invariant"); |
tonyp@2963 | 102 | } else { |
tonyp@2963 | 103 | // next_bottom should match the end of the last/previous region |
tonyp@2963 | 104 | assert(next_bottom == at(index - 1)->end(), "invariant"); |
tonyp@2963 | 105 | } |
tonyp@2963 | 106 | |
tonyp@2963 | 107 | if (index == _allocated_length) { |
tonyp@2963 | 108 | // We have to allocate a new HeapRegion. |
tonyp@2963 | 109 | HeapRegion* new_hr = g1h->new_heap_region(index, next_bottom); |
tonyp@2963 | 110 | if (new_hr == NULL) { |
tonyp@2963 | 111 | // allocation failed, we bail out and return what we have done so far |
tonyp@2963 | 112 | return MemRegion(old_end, next_bottom); |
tonyp@2963 | 113 | } |
tschatzl@5773 | 114 | assert(_regions.get_by_index(index) == NULL, "invariant"); |
tschatzl@5773 | 115 | _regions.set_by_index(index, new_hr); |
brutisso@5074 | 116 | increment_allocated_length(); |
tonyp@2963 | 117 | } |
tonyp@2963 | 118 | // Have to increment the length first, otherwise we will get an |
tonyp@2963 | 119 | // assert failure at(index) below. |
brutisso@5074 | 120 | increment_length(); |
tonyp@2963 | 121 | HeapRegion* hr = at(index); |
tonyp@2963 | 122 | list->add_as_tail(hr); |
tonyp@2963 | 123 | |
tonyp@2963 | 124 | next_bottom = hr->end(); |
tonyp@2472 | 125 | } |
tonyp@2963 | 126 | assert(next_bottom == new_end, "post-condition"); |
tonyp@2963 | 127 | return MemRegion(old_end, next_bottom); |
tonyp@2963 | 128 | } |
tonyp@2963 | 129 | |
tonyp@3713 | 130 | uint HeapRegionSeq::free_suffix() { |
tonyp@3713 | 131 | uint res = 0; |
tonyp@3713 | 132 | uint index = length(); |
tonyp@2963 | 133 | while (index > 0) { |
tonyp@2963 | 134 | index -= 1; |
tonyp@2963 | 135 | if (!at(index)->is_empty()) { |
tonyp@2963 | 136 | break; |
tonyp@2963 | 137 | } |
tonyp@2963 | 138 | res += 1; |
tonyp@2472 | 139 | } |
ysr@777 | 140 | return res; |
ysr@777 | 141 | } |
ysr@777 | 142 | |
tonyp@3713 | 143 | uint HeapRegionSeq::find_contiguous(uint num) { |
tonyp@2963 | 144 | assert(num > 1, "use this only for sequences of length 2 or greater"); |
tonyp@2963 | 145 | assert(_next_search_index <= length(), |
tonyp@3713 | 146 | err_msg("_next_search_index: %u should be valid and <= than %u", |
tonyp@2963 | 147 | _next_search_index, length())); |
tonyp@2963 | 148 | |
tonyp@3713 | 149 | uint start = _next_search_index; |
tonyp@3713 | 150 | uint res = find_contiguous_from(start, num); |
tonyp@2963 | 151 | if (res == G1_NULL_HRS_INDEX && start > 0) { |
tonyp@2963 | 152 | // Try starting from the beginning. If _next_search_index was 0, |
tonyp@2963 | 153 | // no point in doing this again. |
tonyp@2963 | 154 | res = find_contiguous_from(0, num); |
tonyp@2963 | 155 | } |
tonyp@2963 | 156 | if (res != G1_NULL_HRS_INDEX) { |
tonyp@3713 | 157 | assert(res < length(), err_msg("res: %u should be valid", res)); |
tonyp@2963 | 158 | _next_search_index = res + num; |
tonyp@2963 | 159 | assert(_next_search_index <= length(), |
tonyp@3713 | 160 | err_msg("_next_search_index: %u should be valid and <= than %u", |
tonyp@2963 | 161 | _next_search_index, length())); |
tonyp@2963 | 162 | } |
tonyp@2963 | 163 | return res; |
ysr@777 | 164 | } |
ysr@777 | 165 | |
tonyp@2963 | 166 | void HeapRegionSeq::iterate(HeapRegionClosure* blk) const { |
tonyp@2963 | 167 | iterate_from((HeapRegion*) NULL, blk); |
tonyp@2963 | 168 | } |
ysr@777 | 169 | |
tonyp@2963 | 170 | void HeapRegionSeq::iterate_from(HeapRegion* hr, HeapRegionClosure* blk) const { |
tonyp@3713 | 171 | uint hr_index = 0; |
tonyp@2963 | 172 | if (hr != NULL) { |
tonyp@3713 | 173 | hr_index = hr->hrs_index(); |
tonyp@2963 | 174 | } |
ysr@777 | 175 | |
tonyp@3713 | 176 | uint len = length(); |
tonyp@3713 | 177 | for (uint i = hr_index; i < len; i += 1) { |
tonyp@2963 | 178 | bool res = blk->doHeapRegion(at(i)); |
ysr@777 | 179 | if (res) { |
ysr@777 | 180 | blk->incomplete(); |
ysr@777 | 181 | return; |
ysr@777 | 182 | } |
ysr@777 | 183 | } |
tonyp@3713 | 184 | for (uint i = 0; i < hr_index; i += 1) { |
tonyp@2963 | 185 | bool res = blk->doHeapRegion(at(i)); |
ysr@777 | 186 | if (res) { |
ysr@777 | 187 | blk->incomplete(); |
ysr@777 | 188 | return; |
ysr@777 | 189 | } |
ysr@777 | 190 | } |
ysr@777 | 191 | } |
ysr@777 | 192 | |
brutisso@5074 | 193 | uint HeapRegionSeq::shrink_by(uint num_regions_to_remove) { |
tonyp@2472 | 194 | // Reset this in case it's currently pointing into the regions that |
tonyp@2472 | 195 | // we just removed. |
tonyp@2963 | 196 | _next_search_index = 0; |
tonyp@2472 | 197 | |
tonyp@2963 | 198 | assert(length() > 0, "the region sequence should not be empty"); |
tonyp@2963 | 199 | assert(length() <= _allocated_length, "invariant"); |
tonyp@2963 | 200 | assert(_allocated_length > 0, "we should have at least one region committed"); |
brutisso@5074 | 201 | assert(num_regions_to_remove < length(), "We should never remove all regions"); |
ysr@777 | 202 | |
brutisso@5074 | 203 | uint i = 0; |
brutisso@5074 | 204 | for (; i < num_regions_to_remove; i++) { |
brutisso@5074 | 205 | HeapRegion* cur = at(length() - 1); |
tonyp@2963 | 206 | |
brutisso@5074 | 207 | if (!cur->is_empty()) { |
brutisso@5074 | 208 | // We have to give up if the region can not be moved |
brutisso@5074 | 209 | break; |
ysr@777 | 210 | } |
brutisso@5074 | 211 | assert(!cur->isHumongous(), "Humongous regions should not be empty"); |
brutisso@5074 | 212 | |
brutisso@5074 | 213 | decrement_length(); |
brutisso@5074 | 214 | } |
brutisso@5074 | 215 | return i; |
ysr@777 | 216 | } |
ysr@777 | 217 | |
tonyp@2963 | 218 | #ifndef PRODUCT |
tonyp@2963 | 219 | void HeapRegionSeq::verify_optional() { |
tschatzl@5773 | 220 | guarantee(length() <= _allocated_length, |
tonyp@3713 | 221 | err_msg("invariant: _length: %u _allocated_length: %u", |
tschatzl@5773 | 222 | length(), _allocated_length)); |
tschatzl@5773 | 223 | guarantee(_allocated_length <= max_length(), |
tonyp@3713 | 224 | err_msg("invariant: _allocated_length: %u _max_length: %u", |
tschatzl@5773 | 225 | _allocated_length, max_length())); |
tschatzl@5773 | 226 | guarantee(_next_search_index <= length(), |
tonyp@3713 | 227 | err_msg("invariant: _next_search_index: %u _length: %u", |
tschatzl@5773 | 228 | _next_search_index, length())); |
tonyp@2963 | 229 | |
tschatzl@5773 | 230 | HeapWord* prev_end = heap_bottom(); |
tonyp@3713 | 231 | for (uint i = 0; i < _allocated_length; i += 1) { |
tschatzl@5773 | 232 | HeapRegion* hr = _regions.get_by_index(i); |
tonyp@3713 | 233 | guarantee(hr != NULL, err_msg("invariant: i: %u", i)); |
tonyp@2963 | 234 | guarantee(hr->bottom() == prev_end, |
tonyp@3713 | 235 | err_msg("invariant i: %u "HR_FORMAT" prev_end: "PTR_FORMAT, |
drchase@6680 | 236 | i, HR_FORMAT_PARAMS(hr), p2i(prev_end))); |
tonyp@2963 | 237 | guarantee(hr->hrs_index() == i, |
tonyp@3713 | 238 | err_msg("invariant: i: %u hrs_index(): %u", i, hr->hrs_index())); |
tschatzl@5773 | 239 | if (i < length()) { |
tonyp@2963 | 240 | // Asserts will fire if i is >= _length |
tonyp@2963 | 241 | HeapWord* addr = hr->bottom(); |
tonyp@2963 | 242 | guarantee(addr_to_region(addr) == hr, "sanity"); |
tonyp@2963 | 243 | guarantee(addr_to_region_unsafe(addr) == hr, "sanity"); |
tonyp@2963 | 244 | } else { |
tonyp@2963 | 245 | guarantee(hr->is_empty(), "sanity"); |
tonyp@2963 | 246 | guarantee(!hr->isHumongous(), "sanity"); |
tonyp@2963 | 247 | // using assert instead of guarantee here since containing_set() |
tonyp@2963 | 248 | // is only available in non-product builds. |
tonyp@2963 | 249 | assert(hr->containing_set() == NULL, "sanity"); |
tonyp@2963 | 250 | } |
tonyp@2963 | 251 | if (hr->startsHumongous()) { |
tonyp@2963 | 252 | prev_end = hr->orig_end(); |
tonyp@2963 | 253 | } else { |
tonyp@2963 | 254 | prev_end = hr->end(); |
tonyp@2963 | 255 | } |
ysr@777 | 256 | } |
tschatzl@5773 | 257 | for (uint i = _allocated_length; i < max_length(); i += 1) { |
tschatzl@5773 | 258 | guarantee(_regions.get_by_index(i) == NULL, err_msg("invariant i: %u", i)); |
tonyp@2963 | 259 | } |
ysr@777 | 260 | } |
tonyp@2963 | 261 | #endif // PRODUCT |