jdk/src/hotspot/share/gc/z/zNMethodTableIteration.cpp
Stefan Karlsson d20034b09c 8307058: Implementation of Generational ZGC
Co-authored-by: Stefan Karlsson <stefank@openjdk.org>
Co-authored-by: Erik Österlund <eosterlund@openjdk.org>
Co-authored-by: Axel Boldt-Christmas <aboldtch@openjdk.org>
Co-authored-by: Per Liden <pliden@openjdk.org>
Co-authored-by: Stefan Johansson <sjohanss@openjdk.org>
Co-authored-by: Albert Mingkun Yang <ayang@openjdk.org>
Co-authored-by: Erik Helin <ehelin@openjdk.org>
Co-authored-by: Roberto Castañeda Lozano <rcastanedalo@openjdk.org>
Co-authored-by: Nils Eliasson <neliasso@openjdk.org>
Co-authored-by: Martin Doerr <mdoerr@openjdk.org>
Co-authored-by: Leslie Zhai <lzhai@openjdk.org>
Co-authored-by: Fei Yang <fyang@openjdk.org>
Co-authored-by: Yadong Wang <yadongwang@openjdk.org>
Reviewed-by: eosterlund, aboldtch, rcastanedalo
2023-05-11 13:59:37 +00:00

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2.6 KiB
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/*
* Copyright (c) 2017, 2023, 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/z/zNMethodTableEntry.hpp"
#include "gc/z/zNMethodTableIteration.hpp"
#include "memory/iterator.hpp"
#include "runtime/atomic.hpp"
#include "utilities/debug.hpp"
#include "utilities/globalDefinitions.hpp"
ZNMethodTableIteration::ZNMethodTableIteration() :
_table(nullptr),
_size(0),
_claimed(0) {}
bool ZNMethodTableIteration::in_progress() const {
return _table != nullptr;
}
void ZNMethodTableIteration::nmethods_do_begin(ZNMethodTableEntry* table, size_t size) {
assert(!in_progress(), "precondition");
_table = table;
_size = size;
_claimed = 0;
}
void ZNMethodTableIteration::nmethods_do_end() {
assert(_claimed >= _size, "Failed to claim all table entries");
// Finish iteration
_table = nullptr;
}
void ZNMethodTableIteration::nmethods_do(NMethodClosure* cl) {
for (;;) {
// Claim table partition. Each partition is currently sized to span
// two cache lines. This number is just a guess, but seems to work well.
const size_t partition_size = (ZCacheLineSize * 2) / sizeof(ZNMethodTableEntry);
const size_t partition_start = MIN2(Atomic::fetch_and_add(&_claimed, partition_size), _size);
const size_t partition_end = MIN2(partition_start + partition_size, _size);
if (partition_start == partition_end) {
// End of table
break;
}
// Process table partition
for (size_t i = partition_start; i < partition_end; i++) {
const ZNMethodTableEntry entry = _table[i];
if (entry.registered()) {
cl->do_nmethod(entry.method());
}
}
}
}