ysr@777: /* tonyp@2453: * Copyright (c) 2001, 2011, Oracle and/or its affiliates. All rights reserved. ysr@777: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. ysr@777: * ysr@777: * This code is free software; you can redistribute it and/or modify it ysr@777: * under the terms of the GNU General Public License version 2 only, as ysr@777: * published by the Free Software Foundation. ysr@777: * ysr@777: * This code is distributed in the hope that it will be useful, but WITHOUT ysr@777: * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or ysr@777: * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License ysr@777: * version 2 for more details (a copy is included in the LICENSE file that ysr@777: * accompanied this code). ysr@777: * ysr@777: * You should have received a copy of the GNU General Public License version ysr@777: * 2 along with this work; if not, write to the Free Software Foundation, ysr@777: * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. ysr@777: * trims@1907: * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA trims@1907: * or visit www.oracle.com if you need additional information or have any trims@1907: * questions. ysr@777: * ysr@777: */ ysr@777: stefank@2314: #include "precompiled.hpp" stefank@2314: #include "gc_implementation/g1/g1BlockOffsetTable.inline.hpp" stefank@2314: #include "memory/space.hpp" stefank@2314: #include "oops/oop.inline.hpp" stefank@2314: #include "runtime/java.hpp" zgu@3900: #include "services/memTracker.hpp" ysr@777: ysr@777: ////////////////////////////////////////////////////////////////////// ysr@777: // G1BlockOffsetSharedArray ysr@777: ////////////////////////////////////////////////////////////////////// ysr@777: ysr@777: G1BlockOffsetSharedArray::G1BlockOffsetSharedArray(MemRegion reserved, ysr@777: size_t init_word_size) : ysr@777: _reserved(reserved), _end(NULL) ysr@777: { ysr@777: size_t size = compute_size(reserved.word_size()); ysr@777: ReservedSpace rs(ReservedSpace::allocation_align_size_up(size)); ysr@777: if (!rs.is_reserved()) { ysr@777: vm_exit_during_initialization("Could not reserve enough space for heap offset array"); ysr@777: } ysr@777: if (!_vs.initialize(rs, 0)) { ysr@777: vm_exit_during_initialization("Could not reserve enough space for heap offset array"); ysr@777: } zgu@3900: zgu@3900: MemTracker::record_virtual_memory_type((address)rs.base(), mtGC); zgu@3900: ysr@777: _offset_array = (u_char*)_vs.low_boundary(); ysr@777: resize(init_word_size); ysr@777: if (TraceBlockOffsetTable) { ysr@777: gclog_or_tty->print_cr("G1BlockOffsetSharedArray::G1BlockOffsetSharedArray: "); ysr@777: gclog_or_tty->print_cr(" " ysr@777: " rs.base(): " INTPTR_FORMAT ysr@777: " rs.size(): " INTPTR_FORMAT ysr@777: " rs end(): " INTPTR_FORMAT, ysr@777: rs.base(), rs.size(), rs.base() + rs.size()); ysr@777: gclog_or_tty->print_cr(" " ysr@777: " _vs.low_boundary(): " INTPTR_FORMAT ysr@777: " _vs.high_boundary(): " INTPTR_FORMAT, ysr@777: _vs.low_boundary(), ysr@777: _vs.high_boundary()); ysr@777: } ysr@777: } ysr@777: ysr@777: void G1BlockOffsetSharedArray::resize(size_t new_word_size) { ysr@777: assert(new_word_size <= _reserved.word_size(), "Resize larger than reserved"); ysr@777: size_t new_size = compute_size(new_word_size); ysr@777: size_t old_size = _vs.committed_size(); ysr@777: size_t delta; ysr@777: char* high = _vs.high(); ysr@777: _end = _reserved.start() + new_word_size; ysr@777: if (new_size > old_size) { ysr@777: delta = ReservedSpace::page_align_size_up(new_size - old_size); ysr@777: assert(delta > 0, "just checking"); ysr@777: if (!_vs.expand_by(delta)) { ysr@777: // Do better than this for Merlin ysr@777: vm_exit_out_of_memory(delta, "offset table expansion"); ysr@777: } ysr@777: assert(_vs.high() == high + delta, "invalid expansion"); ysr@777: // Initialization of the contents is left to the ysr@777: // G1BlockOffsetArray that uses it. ysr@777: } else { ysr@777: delta = ReservedSpace::page_align_size_down(old_size - new_size); ysr@777: if (delta == 0) return; ysr@777: _vs.shrink_by(delta); ysr@777: assert(_vs.high() == high - delta, "invalid expansion"); ysr@777: } ysr@777: } ysr@777: ysr@777: bool G1BlockOffsetSharedArray::is_card_boundary(HeapWord* p) const { ysr@777: assert(p >= _reserved.start(), "just checking"); ysr@777: size_t delta = pointer_delta(p, _reserved.start()); ysr@777: return (delta & right_n_bits(LogN_words)) == (size_t)NoBits; ysr@777: } ysr@777: ysr@777: ysr@777: ////////////////////////////////////////////////////////////////////// ysr@777: // G1BlockOffsetArray ysr@777: ////////////////////////////////////////////////////////////////////// ysr@777: ysr@777: G1BlockOffsetArray::G1BlockOffsetArray(G1BlockOffsetSharedArray* array, ysr@777: MemRegion mr, bool init_to_zero) : ysr@777: G1BlockOffsetTable(mr.start(), mr.end()), ysr@777: _unallocated_block(_bottom), ysr@777: _array(array), _csp(NULL), ysr@777: _init_to_zero(init_to_zero) { ysr@777: assert(_bottom <= _end, "arguments out of order"); ysr@777: if (!_init_to_zero) { ysr@777: // initialize cards to point back to mr.start() ysr@777: set_remainder_to_point_to_start(mr.start() + N_words, mr.end()); ysr@777: _array->set_offset_array(0, 0); // set first card to 0 ysr@777: } ysr@777: } ysr@777: ysr@777: void G1BlockOffsetArray::set_space(Space* sp) { ysr@777: _sp = sp; ysr@777: _csp = sp->toContiguousSpace(); ysr@777: } ysr@777: ysr@777: // The arguments follow the normal convention of denoting ysr@777: // a right-open interval: [start, end) ysr@777: void ysr@777: G1BlockOffsetArray:: set_remainder_to_point_to_start(HeapWord* start, HeapWord* end) { ysr@777: ysr@777: if (start >= end) { ysr@777: // The start address is equal to the end address (or to ysr@777: // the right of the end address) so there are not cards ysr@777: // that need to be updated.. ysr@777: return; ysr@777: } ysr@777: ysr@777: // Write the backskip value for each region. ysr@777: // ysr@777: // offset ysr@777: // card 2nd 3rd ysr@777: // | +- 1st | | ysr@777: // v v v v ysr@777: // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+- ysr@777: // |x|0|0|0|0|0|0|0|1|1|1|1|1|1| ... |1|1|1|1|2|2|2|2|2|2| ... ysr@777: // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+- ysr@777: // 11 19 75 ysr@777: // 12 ysr@777: // ysr@777: // offset card is the card that points to the start of an object ysr@777: // x - offset value of offset card ysr@777: // 1st - start of first logarithmic region ysr@777: // 0 corresponds to logarithmic value N_words + 0 and 2**(3 * 0) = 1 ysr@777: // 2nd - start of second logarithmic region ysr@777: // 1 corresponds to logarithmic value N_words + 1 and 2**(3 * 1) = 8 ysr@777: // 3rd - start of third logarithmic region ysr@777: // 2 corresponds to logarithmic value N_words + 2 and 2**(3 * 2) = 64 ysr@777: // ysr@777: // integer below the block offset entry is an example of ysr@777: // the index of the entry ysr@777: // ysr@777: // Given an address, ysr@777: // Find the index for the address ysr@777: // Find the block offset table entry ysr@777: // Convert the entry to a back slide ysr@777: // (e.g., with today's, offset = 0x81 => ysr@777: // back slip = 2**(3*(0x81 - N_words)) = 2**3) = 8 ysr@777: // Move back N (e.g., 8) entries and repeat with the ysr@777: // value of the new entry ysr@777: // ysr@777: size_t start_card = _array->index_for(start); ysr@777: size_t end_card = _array->index_for(end-1); ysr@777: assert(start ==_array->address_for_index(start_card), "Precondition"); ysr@777: assert(end ==_array->address_for_index(end_card)+N_words, "Precondition"); ysr@777: set_remainder_to_point_to_start_incl(start_card, end_card); // closed interval ysr@777: } ysr@777: ysr@777: // Unlike the normal convention in this code, the argument here denotes ysr@777: // a closed, inclusive interval: [start_card, end_card], cf set_remainder_to_point_to_start() ysr@777: // above. ysr@777: void ysr@777: G1BlockOffsetArray::set_remainder_to_point_to_start_incl(size_t start_card, size_t end_card) { ysr@777: if (start_card > end_card) { ysr@777: return; ysr@777: } ysr@777: assert(start_card > _array->index_for(_bottom), "Cannot be first card"); ysr@777: assert(_array->offset_array(start_card-1) <= N_words, tonyp@2241: "Offset card has an unexpected value"); ysr@777: size_t start_card_for_region = start_card; ysr@777: u_char offset = max_jubyte; ysr@777: for (int i = 0; i < BlockOffsetArray::N_powers; i++) { ysr@777: // -1 so that the the card with the actual offset is counted. Another -1 ysr@777: // so that the reach ends in this region and not at the start ysr@777: // of the next. ysr@777: size_t reach = start_card - 1 + (BlockOffsetArray::power_to_cards_back(i+1) - 1); ysr@777: offset = N_words + i; ysr@777: if (reach >= end_card) { ysr@777: _array->set_offset_array(start_card_for_region, end_card, offset); ysr@777: start_card_for_region = reach + 1; ysr@777: break; ysr@777: } ysr@777: _array->set_offset_array(start_card_for_region, reach, offset); ysr@777: start_card_for_region = reach + 1; ysr@777: } ysr@777: assert(start_card_for_region > end_card, "Sanity check"); ysr@777: DEBUG_ONLY(check_all_cards(start_card, end_card);) ysr@777: } ysr@777: ysr@777: // The block [blk_start, blk_end) has been allocated; ysr@777: // adjust the block offset table to represent this information; ysr@777: // right-open interval: [blk_start, blk_end) ysr@777: void ysr@777: G1BlockOffsetArray::alloc_block(HeapWord* blk_start, HeapWord* blk_end) { ysr@777: mark_block(blk_start, blk_end); ysr@777: allocated(blk_start, blk_end); ysr@777: } ysr@777: ysr@777: // Adjust BOT to show that a previously whole block has been split ysr@777: // into two. ysr@777: void G1BlockOffsetArray::split_block(HeapWord* blk, size_t blk_size, ysr@777: size_t left_blk_size) { ysr@777: // Verify that the BOT shows [blk, blk + blk_size) to be one block. ysr@777: verify_single_block(blk, blk_size); ysr@777: // Update the BOT to indicate that [blk + left_blk_size, blk + blk_size) ysr@777: // is one single block. ysr@777: mark_block(blk + left_blk_size, blk + blk_size); ysr@777: } ysr@777: ysr@777: ysr@777: // Action_mark - update the BOT for the block [blk_start, blk_end). ysr@777: // Current typical use is for splitting a block. tonyp@2453: // Action_single - update the BOT for an allocation. ysr@777: // Action_verify - BOT verification. ysr@777: void G1BlockOffsetArray::do_block_internal(HeapWord* blk_start, ysr@777: HeapWord* blk_end, ysr@777: Action action) { ysr@777: assert(Universe::heap()->is_in_reserved(blk_start), ysr@777: "reference must be into the heap"); ysr@777: assert(Universe::heap()->is_in_reserved(blk_end-1), ysr@777: "limit must be within the heap"); ysr@777: // This is optimized to make the test fast, assuming we only rarely ysr@777: // cross boundaries. ysr@777: uintptr_t end_ui = (uintptr_t)(blk_end - 1); ysr@777: uintptr_t start_ui = (uintptr_t)blk_start; ysr@777: // Calculate the last card boundary preceding end of blk ysr@777: intptr_t boundary_before_end = (intptr_t)end_ui; ysr@777: clear_bits(boundary_before_end, right_n_bits(LogN)); ysr@777: if (start_ui <= (uintptr_t)boundary_before_end) { ysr@777: // blk starts at or crosses a boundary ysr@777: // Calculate index of card on which blk begins ysr@777: size_t start_index = _array->index_for(blk_start); ysr@777: // Index of card on which blk ends ysr@777: size_t end_index = _array->index_for(blk_end - 1); ysr@777: // Start address of card on which blk begins ysr@777: HeapWord* boundary = _array->address_for_index(start_index); ysr@777: assert(boundary <= blk_start, "blk should start at or after boundary"); ysr@777: if (blk_start != boundary) { ysr@777: // blk starts strictly after boundary ysr@777: // adjust card boundary and start_index forward to next card ysr@777: boundary += N_words; ysr@777: start_index++; ysr@777: } ysr@777: assert(start_index <= end_index, "monotonicity of index_for()"); ysr@777: assert(boundary <= (HeapWord*)boundary_before_end, "tautology"); ysr@777: switch (action) { ysr@777: case Action_mark: { ysr@777: if (init_to_zero()) { ysr@777: _array->set_offset_array(start_index, boundary, blk_start); ysr@777: break; ysr@777: } // Else fall through to the next case ysr@777: } ysr@777: case Action_single: { ysr@777: _array->set_offset_array(start_index, boundary, blk_start); ysr@777: // We have finished marking the "offset card". We need to now ysr@777: // mark the subsequent cards that this blk spans. ysr@777: if (start_index < end_index) { ysr@777: HeapWord* rem_st = _array->address_for_index(start_index) + N_words; ysr@777: HeapWord* rem_end = _array->address_for_index(end_index) + N_words; ysr@777: set_remainder_to_point_to_start(rem_st, rem_end); ysr@777: } ysr@777: break; ysr@777: } ysr@777: case Action_check: { ysr@777: _array->check_offset_array(start_index, boundary, blk_start); ysr@777: // We have finished checking the "offset card". We need to now ysr@777: // check the subsequent cards that this blk spans. ysr@777: check_all_cards(start_index + 1, end_index); ysr@777: break; ysr@777: } ysr@777: default: ysr@777: ShouldNotReachHere(); ysr@777: } ysr@777: } ysr@777: } ysr@777: ysr@777: // The card-interval [start_card, end_card] is a closed interval; this ysr@777: // is an expensive check -- use with care and only under protection of ysr@777: // suitable flag. ysr@777: void G1BlockOffsetArray::check_all_cards(size_t start_card, size_t end_card) const { ysr@777: ysr@777: if (end_card < start_card) { ysr@777: return; ysr@777: } ysr@777: guarantee(_array->offset_array(start_card) == N_words, "Wrong value in second card"); ysr@777: for (size_t c = start_card + 1; c <= end_card; c++ /* yeah! */) { ysr@777: u_char entry = _array->offset_array(c); ysr@777: if (c - start_card > BlockOffsetArray::power_to_cards_back(1)) { ysr@777: guarantee(entry > N_words, "Should be in logarithmic region"); ysr@777: } ysr@777: size_t backskip = BlockOffsetArray::entry_to_cards_back(entry); ysr@777: size_t landing_card = c - backskip; ysr@777: guarantee(landing_card >= (start_card - 1), "Inv"); ysr@777: if (landing_card >= start_card) { ysr@777: guarantee(_array->offset_array(landing_card) <= entry, "monotonicity"); ysr@777: } else { ysr@777: guarantee(landing_card == start_card - 1, "Tautology"); ysr@777: guarantee(_array->offset_array(landing_card) <= N_words, "Offset value"); ysr@777: } ysr@777: } ysr@777: } ysr@777: ysr@777: // The range [blk_start, blk_end) represents a single contiguous block ysr@777: // of storage; modify the block offset table to represent this ysr@777: // information; Right-open interval: [blk_start, blk_end) ysr@777: // NOTE: this method does _not_ adjust _unallocated_block. ysr@777: void ysr@777: G1BlockOffsetArray::single_block(HeapWord* blk_start, HeapWord* blk_end) { ysr@777: do_block_internal(blk_start, blk_end, Action_single); ysr@777: } ysr@777: ysr@777: // Mark the BOT such that if [blk_start, blk_end) straddles a card ysr@777: // boundary, the card following the first such boundary is marked ysr@777: // with the appropriate offset. ysr@777: // NOTE: this method does _not_ adjust _unallocated_block or ysr@777: // any cards subsequent to the first one. ysr@777: void ysr@777: G1BlockOffsetArray::mark_block(HeapWord* blk_start, HeapWord* blk_end) { ysr@777: do_block_internal(blk_start, blk_end, Action_mark); ysr@777: } ysr@777: ysr@777: HeapWord* G1BlockOffsetArray::block_start_unsafe(const void* addr) { ysr@777: assert(_bottom <= addr && addr < _end, ysr@777: "addr must be covered by this Array"); ysr@777: // Must read this exactly once because it can be modified by parallel ysr@777: // allocation. ysr@777: HeapWord* ub = _unallocated_block; ysr@777: if (BlockOffsetArrayUseUnallocatedBlock && addr >= ub) { ysr@777: assert(ub < _end, "tautology (see above)"); ysr@777: return ub; ysr@777: } ysr@777: // Otherwise, find the block start using the table. ysr@777: HeapWord* q = block_at_or_preceding(addr, false, 0); ysr@777: return forward_to_block_containing_addr(q, addr); ysr@777: } ysr@777: ysr@777: // This duplicates a little code from the above: unavoidable. ysr@777: HeapWord* ysr@777: G1BlockOffsetArray::block_start_unsafe_const(const void* addr) const { ysr@777: assert(_bottom <= addr && addr < _end, ysr@777: "addr must be covered by this Array"); ysr@777: // Must read this exactly once because it can be modified by parallel ysr@777: // allocation. ysr@777: HeapWord* ub = _unallocated_block; ysr@777: if (BlockOffsetArrayUseUnallocatedBlock && addr >= ub) { ysr@777: assert(ub < _end, "tautology (see above)"); ysr@777: return ub; ysr@777: } ysr@777: // Otherwise, find the block start using the table. ysr@777: HeapWord* q = block_at_or_preceding(addr, false, 0); ysr@777: HeapWord* n = q + _sp->block_size(q); ysr@777: return forward_to_block_containing_addr_const(q, n, addr); ysr@777: } ysr@777: ysr@777: ysr@777: HeapWord* ysr@777: G1BlockOffsetArray::forward_to_block_containing_addr_slow(HeapWord* q, ysr@777: HeapWord* n, ysr@777: const void* addr) { ysr@777: // We're not in the normal case. We need to handle an important subcase ysr@777: // here: LAB allocation. An allocation previously recorded in the ysr@777: // offset table was actually a lab allocation, and was divided into ysr@777: // several objects subsequently. Fix this situation as we answer the ysr@777: // query, by updating entries as we cross them. iveresov@787: iveresov@787: // If the fist object's end q is at the card boundary. Start refining iveresov@787: // with the corresponding card (the value of the entry will be basically iveresov@787: // set to 0). If the object crosses the boundary -- start from the next card. iveresov@787: size_t next_index = _array->index_for(n) + !_array->is_card_boundary(n); ysr@777: HeapWord* next_boundary = _array->address_for_index(next_index); ysr@777: if (csp() != NULL) { ysr@777: if (addr >= csp()->top()) return csp()->top(); ysr@777: while (next_boundary < addr) { ysr@777: while (n <= next_boundary) { ysr@777: q = n; ysr@777: oop obj = oop(q); ysr@1280: if (obj->klass_or_null() == NULL) return q; ysr@777: n += obj->size(); ysr@777: } ysr@777: assert(q <= next_boundary && n > next_boundary, "Consequence of loop"); ysr@777: // [q, n) is the block that crosses the boundary. ysr@777: alloc_block_work2(&next_boundary, &next_index, q, n); ysr@777: } ysr@777: } else { ysr@777: while (next_boundary < addr) { ysr@777: while (n <= next_boundary) { ysr@777: q = n; ysr@777: oop obj = oop(q); ysr@1280: if (obj->klass_or_null() == NULL) return q; ysr@777: n += _sp->block_size(q); ysr@777: } ysr@777: assert(q <= next_boundary && n > next_boundary, "Consequence of loop"); ysr@777: // [q, n) is the block that crosses the boundary. ysr@777: alloc_block_work2(&next_boundary, &next_index, q, n); ysr@777: } ysr@777: } ysr@777: return forward_to_block_containing_addr_const(q, n, addr); ysr@777: } ysr@777: ysr@777: HeapWord* G1BlockOffsetArray::block_start_careful(const void* addr) const { ysr@777: assert(_array->offset_array(0) == 0, "objects can't cross covered areas"); ysr@777: ysr@777: assert(_bottom <= addr && addr < _end, ysr@777: "addr must be covered by this Array"); ysr@777: // Must read this exactly once because it can be modified by parallel ysr@777: // allocation. ysr@777: HeapWord* ub = _unallocated_block; ysr@777: if (BlockOffsetArrayUseUnallocatedBlock && addr >= ub) { ysr@777: assert(ub < _end, "tautology (see above)"); ysr@777: return ub; ysr@777: } ysr@777: ysr@777: // Otherwise, find the block start using the table, but taking ysr@777: // care (cf block_start_unsafe() above) not to parse any objects/blocks ysr@777: // on the cards themsleves. ysr@777: size_t index = _array->index_for(addr); ysr@777: assert(_array->address_for_index(index) == addr, ysr@777: "arg should be start of card"); ysr@777: ysr@777: HeapWord* q = (HeapWord*)addr; ysr@777: uint offset; ysr@777: do { ysr@777: offset = _array->offset_array(index--); ysr@777: q -= offset; ysr@777: } while (offset == N_words); ysr@777: assert(q <= addr, "block start should be to left of arg"); ysr@777: return q; ysr@777: } ysr@777: ysr@777: // Note that the committed size of the covered space may have changed, ysr@777: // so the table size might also wish to change. ysr@777: void G1BlockOffsetArray::resize(size_t new_word_size) { ysr@777: HeapWord* new_end = _bottom + new_word_size; ysr@777: if (_end < new_end && !init_to_zero()) { ysr@777: // verify that the old and new boundaries are also card boundaries ysr@777: assert(_array->is_card_boundary(_end), ysr@777: "_end not a card boundary"); ysr@777: assert(_array->is_card_boundary(new_end), ysr@777: "new _end would not be a card boundary"); ysr@777: // set all the newly added cards ysr@777: _array->set_offset_array(_end, new_end, N_words); ysr@777: } ysr@777: _end = new_end; // update _end ysr@777: } ysr@777: ysr@777: void G1BlockOffsetArray::set_region(MemRegion mr) { ysr@777: _bottom = mr.start(); ysr@777: _end = mr.end(); ysr@777: } ysr@777: ysr@777: // ysr@777: // threshold_ ysr@777: // | _index_ ysr@777: // v v ysr@777: // +-------+-------+-------+-------+-------+ ysr@777: // | i-1 | i | i+1 | i+2 | i+3 | ysr@777: // +-------+-------+-------+-------+-------+ ysr@777: // ( ^ ] ysr@777: // block-start ysr@777: // ysr@777: void G1BlockOffsetArray::alloc_block_work2(HeapWord** threshold_, size_t* index_, ysr@777: HeapWord* blk_start, HeapWord* blk_end) { ysr@777: // For efficiency, do copy-in/copy-out. ysr@777: HeapWord* threshold = *threshold_; ysr@777: size_t index = *index_; ysr@777: ysr@777: assert(blk_start != NULL && blk_end > blk_start, ysr@777: "phantom block"); ysr@777: assert(blk_end > threshold, "should be past threshold"); jcoomes@1844: assert(blk_start <= threshold, "blk_start should be at or before threshold"); ysr@777: assert(pointer_delta(threshold, blk_start) <= N_words, ysr@777: "offset should be <= BlockOffsetSharedArray::N"); ysr@777: assert(Universe::heap()->is_in_reserved(blk_start), ysr@777: "reference must be into the heap"); ysr@777: assert(Universe::heap()->is_in_reserved(blk_end-1), ysr@777: "limit must be within the heap"); ysr@777: assert(threshold == _array->_reserved.start() + index*N_words, ysr@777: "index must agree with threshold"); ysr@777: ysr@777: DEBUG_ONLY(size_t orig_index = index;) ysr@777: ysr@777: // Mark the card that holds the offset into the block. Note ysr@777: // that _next_offset_index and _next_offset_threshold are not ysr@777: // updated until the end of this method. ysr@777: _array->set_offset_array(index, threshold, blk_start); ysr@777: ysr@777: // We need to now mark the subsequent cards that this blk spans. ysr@777: ysr@777: // Index of card on which blk ends. ysr@777: size_t end_index = _array->index_for(blk_end - 1); ysr@777: ysr@777: // Are there more cards left to be updated? ysr@777: if (index + 1 <= end_index) { ysr@777: HeapWord* rem_st = _array->address_for_index(index + 1); ysr@777: // Calculate rem_end this way because end_index ysr@777: // may be the last valid index in the covered region. ysr@777: HeapWord* rem_end = _array->address_for_index(end_index) + N_words; ysr@777: set_remainder_to_point_to_start(rem_st, rem_end); ysr@777: } ysr@777: ysr@777: index = end_index + 1; ysr@777: // Calculate threshold_ this way because end_index ysr@777: // may be the last valid index in the covered region. ysr@777: threshold = _array->address_for_index(end_index) + N_words; ysr@777: assert(threshold >= blk_end, "Incorrect offset threshold"); ysr@777: ysr@777: // index_ and threshold_ updated here. ysr@777: *threshold_ = threshold; ysr@777: *index_ = index; ysr@777: ysr@777: #ifdef ASSERT ysr@777: // The offset can be 0 if the block starts on a boundary. That ysr@777: // is checked by an assertion above. ysr@777: size_t start_index = _array->index_for(blk_start); ysr@777: HeapWord* boundary = _array->address_for_index(start_index); ysr@777: assert((_array->offset_array(orig_index) == 0 && ysr@777: blk_start == boundary) || ysr@777: (_array->offset_array(orig_index) > 0 && ysr@777: _array->offset_array(orig_index) <= N_words), ysr@777: "offset array should have been set"); ysr@777: for (size_t j = orig_index + 1; j <= end_index; j++) { ysr@777: assert(_array->offset_array(j) > 0 && ysr@777: _array->offset_array(j) <= ysr@777: (u_char) (N_words+BlockOffsetArray::N_powers-1), ysr@777: "offset array should have been set"); ysr@777: } ysr@777: #endif ysr@777: } ysr@777: tonyp@2453: bool tonyp@2453: G1BlockOffsetArray::verify_for_object(HeapWord* obj_start, tonyp@2453: size_t word_size) const { tonyp@2453: size_t first_card = _array->index_for(obj_start); tonyp@2453: size_t last_card = _array->index_for(obj_start + word_size - 1); tonyp@2453: if (!_array->is_card_boundary(obj_start)) { tonyp@2453: // If the object is not on a card boundary the BOT entry of the tonyp@2453: // first card should point to another object so we should not tonyp@2453: // check that one. tonyp@2453: first_card += 1; tonyp@2453: } tonyp@2453: for (size_t card = first_card; card <= last_card; card += 1) { tonyp@2453: HeapWord* card_addr = _array->address_for_index(card); tonyp@2453: HeapWord* block_start = block_start_const(card_addr); tonyp@2453: if (block_start != obj_start) { tonyp@2453: gclog_or_tty->print_cr("block start: "PTR_FORMAT" is incorrect - " tonyp@2453: "card index: "SIZE_FORMAT" " tonyp@2453: "card addr: "PTR_FORMAT" BOT entry: %u " tonyp@2453: "obj: "PTR_FORMAT" word size: "SIZE_FORMAT" " tonyp@2453: "cards: ["SIZE_FORMAT","SIZE_FORMAT"]", tonyp@2453: block_start, card, card_addr, tonyp@2453: _array->offset_array(card), tonyp@2453: obj_start, word_size, first_card, last_card); tonyp@2453: return false; tonyp@2453: } tonyp@2453: } tonyp@2453: return true; tonyp@2453: } tonyp@2453: tonyp@2453: #ifndef PRODUCT tonyp@2241: void tonyp@2453: G1BlockOffsetArray::print_on(outputStream* out) { tonyp@2453: size_t from_index = _array->index_for(_bottom); tonyp@2453: size_t to_index = _array->index_for(_end); tonyp@2453: out->print_cr(">> BOT for area ["PTR_FORMAT","PTR_FORMAT") " tonyp@2453: "cards ["SIZE_FORMAT","SIZE_FORMAT")", tonyp@2453: _bottom, _end, from_index, to_index); tonyp@2453: for (size_t i = from_index; i < to_index; ++i) { tonyp@2453: out->print_cr(" entry "SIZE_FORMAT_W(8)" | "PTR_FORMAT" : %3u", tonyp@2453: i, _array->address_for_index(i), tonyp@2453: (uint) _array->offset_array(i)); tonyp@2453: } tonyp@2241: } tonyp@2453: #endif // !PRODUCT tonyp@2241: ysr@777: ////////////////////////////////////////////////////////////////////// ysr@777: // G1BlockOffsetArrayContigSpace ysr@777: ////////////////////////////////////////////////////////////////////// ysr@777: ysr@777: HeapWord* ysr@777: G1BlockOffsetArrayContigSpace::block_start_unsafe(const void* addr) { ysr@777: assert(_bottom <= addr && addr < _end, ysr@777: "addr must be covered by this Array"); ysr@777: HeapWord* q = block_at_or_preceding(addr, true, _next_offset_index-1); ysr@777: return forward_to_block_containing_addr(q, addr); ysr@777: } ysr@777: ysr@777: HeapWord* ysr@777: G1BlockOffsetArrayContigSpace:: ysr@777: block_start_unsafe_const(const void* addr) const { ysr@777: assert(_bottom <= addr && addr < _end, ysr@777: "addr must be covered by this Array"); ysr@777: HeapWord* q = block_at_or_preceding(addr, true, _next_offset_index-1); ysr@777: HeapWord* n = q + _sp->block_size(q); ysr@777: return forward_to_block_containing_addr_const(q, n, addr); ysr@777: } ysr@777: ysr@777: G1BlockOffsetArrayContigSpace:: ysr@777: G1BlockOffsetArrayContigSpace(G1BlockOffsetSharedArray* array, ysr@777: MemRegion mr) : ysr@777: G1BlockOffsetArray(array, mr, true) ysr@777: { ysr@777: _next_offset_threshold = NULL; ysr@777: _next_offset_index = 0; ysr@777: } ysr@777: ysr@777: HeapWord* G1BlockOffsetArrayContigSpace::initialize_threshold() { ysr@777: assert(!Universe::heap()->is_in_reserved(_array->_offset_array), ysr@777: "just checking"); ysr@777: _next_offset_index = _array->index_for(_bottom); ysr@777: _next_offset_index++; ysr@777: _next_offset_threshold = ysr@777: _array->address_for_index(_next_offset_index); ysr@777: return _next_offset_threshold; ysr@777: } ysr@777: ysr@777: void G1BlockOffsetArrayContigSpace::zero_bottom_entry() { ysr@777: assert(!Universe::heap()->is_in_reserved(_array->_offset_array), ysr@777: "just checking"); ysr@777: size_t bottom_index = _array->index_for(_bottom); ysr@777: assert(_array->address_for_index(bottom_index) == _bottom, ysr@777: "Precondition of call"); ysr@777: _array->set_offset_array(bottom_index, 0); ysr@777: } tonyp@2241: tonyp@2241: void tonyp@2453: G1BlockOffsetArrayContigSpace::set_for_starts_humongous(HeapWord* new_top) { tonyp@2453: assert(new_top <= _end, "_end should have already been updated"); tonyp@2241: tonyp@2453: // The first BOT entry should have offset 0. tonyp@2453: zero_bottom_entry(); tonyp@2453: initialize_threshold(); tonyp@2453: alloc_block(_bottom, new_top); tonyp@2453: } tonyp@2453: tonyp@2453: #ifndef PRODUCT tonyp@2453: void tonyp@2453: G1BlockOffsetArrayContigSpace::print_on(outputStream* out) { tonyp@2453: G1BlockOffsetArray::print_on(out); tonyp@2453: out->print_cr(" next offset threshold: "PTR_FORMAT, _next_offset_threshold); tonyp@2453: out->print_cr(" next offset index: "SIZE_FORMAT, _next_offset_index); tonyp@2241: } tonyp@2453: #endif // !PRODUCT