--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psVirtualspace.hpp Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,175 @@
+/*
+ * Copyright 2003-2005 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+// VirtualSpace for the parallel scavenge collector.
+//
+// VirtualSpace is data structure for committing a previously reserved address
+// range in smaller chunks.
+
+class PSVirtualSpace : public CHeapObj {
+ friend class VMStructs;
+ protected:
+ // The space is committed/uncommited in chunks of size _alignment. The
+ // ReservedSpace passed to initialize() must be aligned to this value.
+ const size_t _alignment;
+
+ // Reserved area
+ char* _reserved_low_addr;
+ char* _reserved_high_addr;
+
+ // Committed area
+ char* _committed_low_addr;
+ char* _committed_high_addr;
+
+ // The entire space has been committed and pinned in memory, no
+ // os::commit_memory() or os::uncommit_memory().
+ bool _special;
+
+ // Convenience wrapper.
+ inline static size_t pointer_delta(const char* left, const char* right);
+
+ public:
+ PSVirtualSpace(ReservedSpace rs, size_t alignment);
+ PSVirtualSpace(ReservedSpace rs);
+
+ ~PSVirtualSpace();
+
+ // Eventually all instances should be created with the above 1- or 2-arg
+ // constructors. Then the 1st constructor below should become protected and
+ // the 2nd ctor and initialize() removed.
+ PSVirtualSpace(size_t alignment): _alignment(alignment) { }
+ PSVirtualSpace();
+ bool initialize(ReservedSpace rs, size_t commit_size);
+
+ bool contains(void* p) const;
+
+ // Accessors (all sizes are bytes).
+ size_t alignment() const { return _alignment; }
+ char* reserved_low_addr() const { return _reserved_low_addr; }
+ char* reserved_high_addr() const { return _reserved_high_addr; }
+ char* committed_low_addr() const { return _committed_low_addr; }
+ char* committed_high_addr() const { return _committed_high_addr; }
+ bool special() const { return _special; }
+
+ inline size_t committed_size() const;
+ inline size_t reserved_size() const;
+ inline size_t uncommitted_size() const;
+
+ // Operations.
+ inline void set_reserved(char* low_addr, char* high_addr, bool special);
+ inline void set_reserved(ReservedSpace rs);
+ inline void set_committed(char* low_addr, char* high_addr);
+ virtual bool expand_by(size_t bytes, bool pre_touch = false);
+ virtual bool shrink_by(size_t bytes);
+ virtual size_t expand_into(PSVirtualSpace* space, size_t bytes);
+ void release();
+
+#ifndef PRODUCT
+ // Debugging
+ static bool is_aligned(size_t val, size_t align);
+ bool is_aligned(size_t val) const;
+ bool is_aligned(char* val) const;
+ void verify() const;
+ void print() const;
+ virtual bool grows_up() const { return true; }
+ bool grows_down() const { return !grows_up(); }
+
+ // Helper class to verify a space when entering/leaving a block.
+ class PSVirtualSpaceVerifier: public StackObj {
+ private:
+ const PSVirtualSpace* const _space;
+ public:
+ PSVirtualSpaceVerifier(PSVirtualSpace* space): _space(space) {
+ _space->verify();
+ }
+ ~PSVirtualSpaceVerifier() { _space->verify(); }
+ };
+#endif
+
+ virtual void print_space_boundaries_on(outputStream* st) const;
+
+ // Included for compatibility with the original VirtualSpace.
+ public:
+ // Committed area
+ char* low() const { return committed_low_addr(); }
+ char* high() const { return committed_high_addr(); }
+
+ // Reserved area
+ char* low_boundary() const { return reserved_low_addr(); }
+ char* high_boundary() const { return reserved_high_addr(); }
+};
+
+// A virtual space that grows from high addresses to low addresses.
+class PSVirtualSpaceHighToLow : public PSVirtualSpace {
+ friend class VMStructs;
+ public:
+ PSVirtualSpaceHighToLow(ReservedSpace rs, size_t alignment);
+ PSVirtualSpaceHighToLow(ReservedSpace rs);
+
+ virtual bool expand_by(size_t bytes, bool pre_touch = false);
+ virtual bool shrink_by(size_t bytes);
+ virtual size_t expand_into(PSVirtualSpace* space, size_t bytes);
+
+ virtual void print_space_boundaries_on(outputStream* st) const;
+
+#ifndef PRODUCT
+ // Debugging
+ virtual bool grows_up() const { return false; }
+#endif
+};
+
+//
+// PSVirtualSpace inlines.
+//
+inline size_t
+PSVirtualSpace::pointer_delta(const char* left, const char* right) {
+ return ::pointer_delta((void *)left, (void*)right, sizeof(char));
+}
+
+inline size_t PSVirtualSpace::committed_size() const {
+ return pointer_delta(committed_high_addr(), committed_low_addr());
+}
+
+inline size_t PSVirtualSpace::reserved_size() const {
+ return pointer_delta(reserved_high_addr(), reserved_low_addr());
+}
+
+inline size_t PSVirtualSpace::uncommitted_size() const {
+ return reserved_size() - committed_size();
+}
+
+inline void PSVirtualSpace::set_reserved(char* low_addr, char* high_addr, bool special) {
+ _reserved_low_addr = low_addr;
+ _reserved_high_addr = high_addr;
+ _special = special;
+}
+
+inline void PSVirtualSpace::set_reserved(ReservedSpace rs) {
+ set_reserved(rs.base(), rs.base() + rs.size(), rs.special());
+}
+
+inline void PSVirtualSpace::set_committed(char* low_addr, char* high_addr) {
+ _committed_low_addr = low_addr;
+ _committed_high_addr = high_addr;
+}