| /* |
| * Copyright (c) 2001, 2017, 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/g1/g1BiasedArray.hpp" |
| #include "gc/g1/g1RegionToSpaceMapper.hpp" |
| #include "memory/allocation.inline.hpp" |
| #include "memory/virtualspace.hpp" |
| #include "services/memTracker.hpp" |
| #include "utilities/align.hpp" |
| #include "utilities/bitMap.inline.hpp" |
| |
| G1RegionToSpaceMapper::G1RegionToSpaceMapper(ReservedSpace rs, |
| size_t used_size, |
| size_t page_size, |
| size_t region_granularity, |
| size_t commit_factor, |
| MemoryType type) : |
| _storage(rs, used_size, page_size), |
| _region_granularity(region_granularity), |
| _listener(NULL), |
| _commit_map(rs.size() * commit_factor / region_granularity, mtGC) { |
| guarantee(is_power_of_2(page_size), "must be"); |
| guarantee(is_power_of_2(region_granularity), "must be"); |
| |
| MemTracker::record_virtual_memory_type((address)rs.base(), type); |
| } |
| |
| // G1RegionToSpaceMapper implementation where the region granularity is larger than |
| // or the same as the commit granularity. |
| // Basically, the space corresponding to one region region spans several OS pages. |
| class G1RegionsLargerThanCommitSizeMapper : public G1RegionToSpaceMapper { |
| private: |
| size_t _pages_per_region; |
| |
| public: |
| G1RegionsLargerThanCommitSizeMapper(ReservedSpace rs, |
| size_t actual_size, |
| size_t page_size, |
| size_t alloc_granularity, |
| size_t commit_factor, |
| MemoryType type) : |
| G1RegionToSpaceMapper(rs, actual_size, page_size, alloc_granularity, commit_factor, type), |
| _pages_per_region(alloc_granularity / (page_size * commit_factor)) { |
| |
| guarantee(alloc_granularity >= page_size, "allocation granularity smaller than commit granularity"); |
| } |
| |
| virtual void commit_regions(uint start_idx, size_t num_regions, WorkGang* pretouch_gang) { |
| size_t const start_page = (size_t)start_idx * _pages_per_region; |
| bool zero_filled = _storage.commit(start_page, num_regions * _pages_per_region); |
| if (AlwaysPreTouch) { |
| _storage.pretouch(start_page, num_regions * _pages_per_region, pretouch_gang); |
| } |
| _commit_map.set_range(start_idx, start_idx + num_regions); |
| fire_on_commit(start_idx, num_regions, zero_filled); |
| } |
| |
| virtual void uncommit_regions(uint start_idx, size_t num_regions) { |
| _storage.uncommit((size_t)start_idx * _pages_per_region, num_regions * _pages_per_region); |
| _commit_map.clear_range(start_idx, start_idx + num_regions); |
| } |
| }; |
| |
| // G1RegionToSpaceMapper implementation where the region granularity is smaller |
| // than the commit granularity. |
| // Basically, the contents of one OS page span several regions. |
| class G1RegionsSmallerThanCommitSizeMapper : public G1RegionToSpaceMapper { |
| private: |
| class CommitRefcountArray : public G1BiasedMappedArray<uint> { |
| protected: |
| virtual uint default_value() const { return 0; } |
| }; |
| |
| size_t _regions_per_page; |
| |
| CommitRefcountArray _refcounts; |
| |
| uintptr_t region_idx_to_page_idx(uint region) const { |
| return region / _regions_per_page; |
| } |
| |
| public: |
| G1RegionsSmallerThanCommitSizeMapper(ReservedSpace rs, |
| size_t actual_size, |
| size_t page_size, |
| size_t alloc_granularity, |
| size_t commit_factor, |
| MemoryType type) : |
| G1RegionToSpaceMapper(rs, actual_size, page_size, alloc_granularity, commit_factor, type), |
| _regions_per_page((page_size * commit_factor) / alloc_granularity), _refcounts() { |
| |
| guarantee((page_size * commit_factor) >= alloc_granularity, "allocation granularity smaller than commit granularity"); |
| _refcounts.initialize((HeapWord*)rs.base(), (HeapWord*)(rs.base() + align_up(rs.size(), page_size)), page_size); |
| } |
| |
| virtual void commit_regions(uint start_idx, size_t num_regions, WorkGang* pretouch_gang) { |
| size_t const NoPage = ~(size_t)0; |
| |
| size_t first_committed = NoPage; |
| size_t num_committed = 0; |
| |
| bool all_zero_filled = true; |
| |
| for (uint i = start_idx; i < start_idx + num_regions; i++) { |
| assert(!_commit_map.at(i), "Trying to commit storage at region %u that is already committed", i); |
| size_t idx = region_idx_to_page_idx(i); |
| uint old_refcount = _refcounts.get_by_index(idx); |
| |
| bool zero_filled = false; |
| if (old_refcount == 0) { |
| if (first_committed == NoPage) { |
| first_committed = idx; |
| num_committed = 1; |
| } else { |
| num_committed++; |
| } |
| zero_filled = _storage.commit(idx, 1); |
| } |
| all_zero_filled &= zero_filled; |
| |
| _refcounts.set_by_index(idx, old_refcount + 1); |
| _commit_map.set_bit(i); |
| } |
| if (AlwaysPreTouch && num_committed > 0) { |
| _storage.pretouch(first_committed, num_committed, pretouch_gang); |
| } |
| fire_on_commit(start_idx, num_regions, all_zero_filled); |
| } |
| |
| virtual void uncommit_regions(uint start_idx, size_t num_regions) { |
| for (uint i = start_idx; i < start_idx + num_regions; i++) { |
| assert(_commit_map.at(i), "Trying to uncommit storage at region %u that is not committed", i); |
| size_t idx = region_idx_to_page_idx(i); |
| uint old_refcount = _refcounts.get_by_index(idx); |
| assert(old_refcount > 0, "must be"); |
| if (old_refcount == 1) { |
| _storage.uncommit(idx, 1); |
| } |
| _refcounts.set_by_index(idx, old_refcount - 1); |
| _commit_map.clear_bit(i); |
| } |
| } |
| }; |
| |
| void G1RegionToSpaceMapper::fire_on_commit(uint start_idx, size_t num_regions, bool zero_filled) { |
| if (_listener != NULL) { |
| _listener->on_commit(start_idx, num_regions, zero_filled); |
| } |
| } |
| |
| G1RegionToSpaceMapper* G1RegionToSpaceMapper::create_mapper(ReservedSpace rs, |
| size_t actual_size, |
| size_t page_size, |
| size_t region_granularity, |
| size_t commit_factor, |
| MemoryType type) { |
| |
| if (region_granularity >= (page_size * commit_factor)) { |
| return new G1RegionsLargerThanCommitSizeMapper(rs, actual_size, page_size, region_granularity, commit_factor, type); |
| } else { |
| return new G1RegionsSmallerThanCommitSizeMapper(rs, actual_size, page_size, region_granularity, commit_factor, type); |
| } |
| } |