src/hotspot/share/gc/z/zPageTable.cpp
changeset 50525 767cdb97f103
child 54094 ed3c6f07faab
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/z/zPageTable.cpp	Tue Jun 12 17:40:28 2018 +0200
@@ -0,0 +1,94 @@
+/*
+ * Copyright (c) 2015, 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/z/zPage.inline.hpp"
+#include "gc/z/zPageTable.inline.hpp"
+#include "runtime/orderAccess.hpp"
+#include "utilities/debug.hpp"
+
+ZPageTable::ZPageTable() :
+    _map() {}
+
+ZPageTableEntry ZPageTable::get_entry(ZPage* page) const {
+  const uintptr_t addr = ZAddress::good(page->start());
+  return _map.get(addr);
+}
+
+void ZPageTable::put_entry(ZPage* page, ZPageTableEntry entry) {
+  // Make sure a newly created page is globally visible before
+  // updating the pagetable.
+  OrderAccess::storestore();
+
+  const uintptr_t start = ZAddress::good(page->start());
+  const uintptr_t end = start + page->size();
+  for (uintptr_t addr = start; addr < end; addr += ZPageSizeMin) {
+    _map.put(addr, entry);
+  }
+}
+
+void ZPageTable::insert(ZPage* page) {
+  assert(get_entry(page).page() == NULL ||
+         get_entry(page).page() == page, "Invalid entry");
+
+  // Cached pages stays in the pagetable and we must not re-insert
+  // those when they get re-allocated because they might also be
+  // relocating and we don't want to clear their relocating bit.
+  if (get_entry(page).page() == NULL) {
+    ZPageTableEntry entry(page, false /* relocating */);
+    put_entry(page, entry);
+  }
+
+  assert(get_entry(page).page() == page, "Invalid entry");
+}
+
+void ZPageTable::remove(ZPage* page) {
+  assert(get_entry(page).page() == page, "Invalid entry");
+
+  ZPageTableEntry entry;
+  put_entry(page, entry);
+
+  assert(get_entry(page).page() == NULL, "Invalid entry");
+}
+
+void ZPageTable::set_relocating(ZPage* page) {
+  assert(get_entry(page).page() == page, "Invalid entry");
+  assert(!get_entry(page).relocating(), "Invalid entry");
+
+  ZPageTableEntry entry(page, true /* relocating */);
+  put_entry(page, entry);
+
+  assert(get_entry(page).page() == page, "Invalid entry");
+  assert(get_entry(page).relocating(), "Invalid entry");
+}
+
+void ZPageTable::clear_relocating(ZPage* page) {
+  assert(get_entry(page).page() == page, "Invalid entry");
+  assert(get_entry(page).relocating(), "Invalid entry");
+
+  ZPageTableEntry entry(page, false /* relocating */);
+  put_entry(page, entry);
+
+  assert(get_entry(page).page() == page, "Invalid entry");
+  assert(!get_entry(page).relocating(), "Invalid entry");
+}