| /* |
| * Copyright (c) 2001, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #include "precompiled.hpp" |
| #include "gc_implementation/parallelScavenge/objectStartArray.hpp" |
| #include "memory/allocation.inline.hpp" |
| #include "memory/cardTableModRefBS.hpp" |
| #include "oops/oop.inline.hpp" |
| #include "runtime/java.hpp" |
| #include "services/memTracker.hpp" |
| |
| void ObjectStartArray::initialize(MemRegion reserved_region) { |
| // We're based on the assumption that we use the same |
| // size blocks as the card table. |
| assert((int)block_size == (int)CardTableModRefBS::card_size, "Sanity"); |
| assert((int)block_size <= 512, "block_size must be less than or equal to 512"); |
| |
| // Calculate how much space must be reserved |
| _reserved_region = reserved_region; |
| |
| size_t bytes_to_reserve = reserved_region.word_size() / block_size_in_words; |
| assert(bytes_to_reserve > 0, "Sanity"); |
| |
| bytes_to_reserve = |
| align_size_up(bytes_to_reserve, os::vm_allocation_granularity()); |
| |
| // Do not use large-pages for the backing store. The one large page region |
| // will be used for the heap proper. |
| ReservedSpace backing_store(bytes_to_reserve); |
| if (!backing_store.is_reserved()) { |
| vm_exit_during_initialization("Could not reserve space for ObjectStartArray"); |
| } |
| MemTracker::record_virtual_memory_type((address)backing_store.base(), mtGC); |
| |
| // We do not commit any memory initially |
| if (!_virtual_space.initialize(backing_store, 0)) { |
| vm_exit_during_initialization("Could not commit space for ObjectStartArray"); |
| } |
| |
| _raw_base = (jbyte*)_virtual_space.low_boundary(); |
| |
| if (_raw_base == NULL) { |
| vm_exit_during_initialization("Could not get raw_base address"); |
| } |
| |
| MemTracker::record_virtual_memory_type((address)_raw_base, mtGC); |
| |
| |
| _offset_base = _raw_base - (size_t(reserved_region.start()) >> block_shift); |
| |
| _covered_region.set_start(reserved_region.start()); |
| _covered_region.set_word_size(0); |
| |
| _blocks_region.set_start((HeapWord*)_raw_base); |
| _blocks_region.set_word_size(0); |
| } |
| |
| void ObjectStartArray::set_covered_region(MemRegion mr) { |
| assert(_reserved_region.contains(mr), "MemRegion outside of reserved space"); |
| assert(_reserved_region.start() == mr.start(), "Attempt to move covered region"); |
| |
| HeapWord* low_bound = mr.start(); |
| HeapWord* high_bound = mr.end(); |
| assert((uintptr_t(low_bound) & (block_size - 1)) == 0, "heap must start at block boundary"); |
| assert((uintptr_t(high_bound) & (block_size - 1)) == 0, "heap must end at block boundary"); |
| |
| size_t requested_blocks_size_in_bytes = mr.word_size() / block_size_in_words; |
| |
| // Only commit memory in page sized chunks |
| requested_blocks_size_in_bytes = |
| align_size_up(requested_blocks_size_in_bytes, os::vm_page_size()); |
| |
| _covered_region = mr; |
| |
| size_t current_blocks_size_in_bytes = _blocks_region.byte_size(); |
| |
| if (requested_blocks_size_in_bytes > current_blocks_size_in_bytes) { |
| // Expand |
| size_t expand_by = requested_blocks_size_in_bytes - current_blocks_size_in_bytes; |
| if (!_virtual_space.expand_by(expand_by)) { |
| vm_exit_out_of_memory(expand_by, OOM_MMAP_ERROR, "object start array expansion"); |
| } |
| // Clear *only* the newly allocated region |
| memset(_blocks_region.end(), clean_block, expand_by); |
| } |
| |
| if (requested_blocks_size_in_bytes < current_blocks_size_in_bytes) { |
| // Shrink |
| size_t shrink_by = current_blocks_size_in_bytes - requested_blocks_size_in_bytes; |
| _virtual_space.shrink_by(shrink_by); |
| } |
| |
| _blocks_region.set_word_size(requested_blocks_size_in_bytes / sizeof(HeapWord)); |
| |
| assert(requested_blocks_size_in_bytes % sizeof(HeapWord) == 0, "Block table not expanded in word sized increment"); |
| assert(requested_blocks_size_in_bytes == _blocks_region.byte_size(), "Sanity"); |
| assert(block_for_addr(low_bound) == &_raw_base[0], "Checking start of map"); |
| assert(block_for_addr(high_bound-1) <= &_raw_base[_blocks_region.byte_size()-1], "Checking end of map"); |
| } |
| |
| void ObjectStartArray::reset() { |
| memset(_blocks_region.start(), clean_block, _blocks_region.byte_size()); |
| } |
| |
| |
| bool ObjectStartArray::object_starts_in_range(HeapWord* start_addr, |
| HeapWord* end_addr) const { |
| assert(start_addr <= end_addr, "range is wrong"); |
| if (start_addr > end_addr) { |
| return false; |
| } |
| |
| jbyte* start_block = block_for_addr(start_addr); |
| jbyte* end_block = block_for_addr(end_addr); |
| |
| for (jbyte* block = start_block; block <= end_block; block++) { |
| if (*block != clean_block) { |
| return true; |
| } |
| } |
| |
| return false; |
| } |