--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1RegionToSpaceMapper.cpp Tue Aug 19 14:09:10 2014 +0200
@@ -0,0 +1,158 @@
+/*
+ * 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/g1/g1BiasedArray.hpp"
+#include "gc_implementation/g1/g1RegionToSpaceMapper.hpp"
+#include "runtime/virtualspace.hpp"
+#include "services/memTracker.hpp"
+#include "utilities/bitMap.inline.hpp"
+
+G1RegionToSpaceMapper::G1RegionToSpaceMapper(ReservedSpace rs,
+ size_t commit_granularity,
+ size_t region_granularity,
+ MemoryType type) :
+ _storage(),
+ _commit_granularity(commit_granularity),
+ _region_granularity(region_granularity),
+ _listener(NULL),
+ _commit_map() {
+ guarantee(is_power_of_2(commit_granularity), "must be");
+ guarantee(is_power_of_2(region_granularity), "must be");
+ _storage.initialize_with_granularity(rs, commit_granularity);
+
+ 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 os_commit_granularity,
+ size_t alloc_granularity,
+ size_t commit_factor,
+ MemoryType type) :
+ G1RegionToSpaceMapper(rs, os_commit_granularity, alloc_granularity, type),
+ _pages_per_region(alloc_granularity / (os_commit_granularity * commit_factor)) {
+
+ guarantee(alloc_granularity >= os_commit_granularity, "allocation granularity smaller than commit granularity");
+ _commit_map.resize(rs.size() * commit_factor / alloc_granularity, /* in_resource_area */ false);
+ }
+
+ virtual void commit_regions(uintptr_t start_idx, size_t num_regions) {
+ _storage.commit(start_idx * _pages_per_region, num_regions * _pages_per_region);
+ _commit_map.set_range(start_idx, start_idx + num_regions);
+ fire_on_commit(start_idx, num_regions);
+ }
+
+ virtual void uncommit_regions(uintptr_t start_idx, size_t num_regions) {
+ _storage.uncommit(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 os_commit_granularity,
+ size_t alloc_granularity,
+ size_t commit_factor,
+ MemoryType type) :
+ G1RegionToSpaceMapper(rs, os_commit_granularity, alloc_granularity, type),
+ _regions_per_page((os_commit_granularity * commit_factor) / alloc_granularity), _refcounts() {
+
+ guarantee((os_commit_granularity * commit_factor) >= alloc_granularity, "allocation granularity smaller than commit granularity");
+ _refcounts.initialize((HeapWord*)rs.base(), (HeapWord*)(rs.base() + rs.size()), os_commit_granularity);
+ _commit_map.resize(rs.size() * commit_factor / alloc_granularity, /* in_resource_area */ false);
+ }
+
+ virtual void commit_regions(uintptr_t start_idx, size_t num_regions) {
+ for (uintptr_t i = start_idx; i < start_idx + num_regions; i++) {
+ assert(!_commit_map.at(i), err_msg("Trying to commit storage at region "INTPTR_FORMAT" that is already committed", i));
+ uintptr_t idx = region_idx_to_page_idx(i);
+ uint old_refcount = _refcounts.get_by_index(idx);
+ if (old_refcount == 0) {
+ _storage.commit(idx, 1);
+ }
+ _refcounts.set_by_index(idx, old_refcount + 1);
+ _commit_map.set_bit(i);
+ fire_on_commit(i, 1);
+ }
+ }
+
+ virtual void uncommit_regions(uintptr_t start_idx, size_t num_regions) {
+ for (uintptr_t i = start_idx; i < start_idx + num_regions; i++) {
+ assert(_commit_map.at(i), err_msg("Trying to uncommit storage at region "INTPTR_FORMAT" that is not committed", i));
+ uintptr_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) {
+ if (_listener != NULL) {
+ _listener->on_commit(start_idx, num_regions);
+ }
+}
+
+G1RegionToSpaceMapper* G1RegionToSpaceMapper::create_mapper(ReservedSpace rs,
+ size_t os_commit_granularity,
+ size_t region_granularity,
+ size_t commit_factor,
+ MemoryType type) {
+
+ if (region_granularity >= (os_commit_granularity * commit_factor)) {
+ return new G1RegionsLargerThanCommitSizeMapper(rs, os_commit_granularity, region_granularity, commit_factor, type);
+ } else {
+ return new G1RegionsSmallerThanCommitSizeMapper(rs, os_commit_granularity, region_granularity, commit_factor, type);
+ }
+}