--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/share/vm/memory/compactingPermGenGen.hpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,248 @@
+/*
+ * Copyright 2003-2006 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.
+ *
+ */
+
+// All heaps contains a "permanent generation," containing permanent
+// (reflective) objects.  This is like a regular generation in some ways,
+// but unlike one in others, and so is split apart.
+
+class PermanentGenerationSpec;
+
+// This is the "generation" view of a CompactingPermGen.
+class CompactingPermGenGen: public OneContigSpaceCardGeneration {
+  friend class VMStructs;
+  // Abstractly, this is a subtype that gets access to protected fields.
+  friend class CompactingPermGen;
+
+private:
+  // Shared spaces
+  PermanentGenerationSpec* _spec;
+  size_t _shared_space_size;
+  VirtualSpace _ro_vs;
+  VirtualSpace _rw_vs;
+  VirtualSpace _md_vs;
+  VirtualSpace _mc_vs;
+  BlockOffsetSharedArray* _ro_bts;
+  BlockOffsetSharedArray* _rw_bts;
+  OffsetTableContigSpace* _ro_space;
+  OffsetTableContigSpace* _rw_space;
+
+  // With shared spaces there is a dicotomy in the use of the
+  // _virtual_space of the generation.  There is a portion of the
+  // _virtual_space that is used for the unshared part of the
+  // permanent generation and a portion that is reserved for the shared part.
+  // The _reserved field in the generation represents both the
+  // unshared and shared parts of the generation.  The _reserved
+  // variable is initialized for only the unshared part but is
+  // later extended to include the shared part during initialization
+  // if shared spaces are being used.
+  // The reserved size for the _virtual_space for CompactingPermGenGen
+  // is the size of the space for the permanent generation including the
+  // the shared spaces.  This can be seen by the use of MaxPermSize
+  // in the allocation of PermanentGenerationSpec.  The space for the
+  // shared spaces is committed separately (???).
+  // In general at initialization only a part of the
+  // space for the unshared part of the permanent generation is
+  // committed and more is committed as the permanent generation is
+  // grown.  In growing the permanent generation the capacity() and
+  // max_capacity() of the generation are used.  For the permanent
+  // generation (implemented with a CompactingPermGenGen) the capacity()
+  // is taken from the capacity of the space (_the_space variable used for the
+  // unshared part of the generation) and the max_capacity() is based
+  // on the size of the _reserved variable (which includes the size of the
+  // shared spaces) minus the size of the shared spaces.
+
+  // These values are redundant, but are called out separately to avoid
+  // going through heap/space/gen pointers for performance.
+  static HeapWord* unshared_bottom;
+  static HeapWord* unshared_end;
+  static HeapWord* shared_bottom;
+  static HeapWord* readonly_bottom;
+  static HeapWord* readonly_end;
+  static HeapWord* readwrite_bottom;
+  static HeapWord* readwrite_end;
+  static HeapWord* miscdata_bottom;
+  static HeapWord* miscdata_end;
+  static HeapWord* misccode_bottom;
+  static HeapWord* misccode_end;
+  static HeapWord* shared_end;
+
+  // List of klassOops whose vtbl entries are used to patch others.
+  static void**        _vtbl_list;
+
+  // Performance Counters
+  GenerationCounters*  _gen_counters;
+  CSpaceCounters*      _space_counters;
+
+  void initialize_performance_counters();
+
+public:
+
+  enum {
+    vtbl_list_size = 16, // number of entries in the shared space vtable list.
+    num_virtuals = 100   // number of virtual methods in Klass (or
+                         // subclass) objects, or greater.
+  };
+
+  enum {
+    ro = 0,  // read-only shared space in the heap
+    rw = 1,  // read-write shared space in the heap
+    md = 2,  // miscellaneous data for initializing tables, etc.
+    mc = 3,  // miscellaneous code - vtable replacement.
+    n_regions = 4
+  };
+
+  CompactingPermGenGen(ReservedSpace rs, ReservedSpace shared_rs,
+                       size_t initial_byte_size, int level, GenRemSet* remset,
+                       ContiguousSpace* space,
+                       PermanentGenerationSpec* perm_spec);
+
+  const char* name() const {
+    return "compacting perm gen";
+  }
+
+  const char* short_name() const {
+    return "Perm";
+  }
+
+  // Return the maximum capacity for the object space.  This
+  // explicitly does not include the shared spaces.
+  size_t max_capacity() const;
+
+  void update_counters();
+
+  void compute_new_size() {
+    assert(false, "Should not call this -- handled at PermGen level.");
+  }
+
+  bool must_be_youngest() const { return false; }
+  bool must_be_oldest() const { return false; }
+
+  OffsetTableContigSpace* ro_space() const { return _ro_space; }
+  OffsetTableContigSpace* rw_space() const { return _rw_space; }
+  VirtualSpace*           md_space()       { return &_md_vs; }
+  VirtualSpace*           mc_space()       { return &_mc_vs; }
+  ContiguousSpace* unshared_space() const { return _the_space; }
+
+  static bool inline is_shared(const oopDesc* p) {
+    return (HeapWord*)p >= shared_bottom && (HeapWord*)p < shared_end;
+  }
+  // RedefineClasses note: this tester is used to check residence of
+  // the specified oop in the shared readonly space and not whether
+  // the oop is readonly.
+  static bool inline is_shared_readonly(const oopDesc* p) {
+    return (HeapWord*)p >= readonly_bottom && (HeapWord*)p < readonly_end;
+  }
+  // RedefineClasses note: this tester is used to check residence of
+  // the specified oop in the shared readwrite space and not whether
+  // the oop is readwrite.
+  static bool inline is_shared_readwrite(const oopDesc* p) {
+    return (HeapWord*)p >= readwrite_bottom && (HeapWord*)p < readwrite_end;
+  }
+
+  bool is_in_unshared(const void* p) const {
+    return OneContigSpaceCardGeneration::is_in(p);
+  }
+
+  bool is_in_shared(const void* p) const {
+   return p >= shared_bottom && p < shared_end;
+   }
+
+  inline bool is_in(const void* p) const {
+    return is_in_unshared(p) || is_in_shared(p);
+  }
+
+  inline PermanentGenerationSpec* spec() const { return _spec; }
+  inline void set_spec(PermanentGenerationSpec* spec) { _spec = spec; }
+
+  void pre_adjust_pointers();
+  void adjust_pointers();
+  void space_iterate(SpaceClosure* blk, bool usedOnly = false);
+  void print_on(outputStream* st) const;
+  void younger_refs_iterate(OopsInGenClosure* blk);
+  void compact();
+  void post_compact();
+  size_t contiguous_available() const;
+  bool grow_by(size_t bytes);
+  void grow_to_reserved();
+
+  void clear_remembered_set();
+  void invalidate_remembered_set();
+
+  inline bool block_is_obj(const HeapWord* addr) const {
+    if      (addr < the_space()->top()) return true;
+    else if (addr < the_space()->end()) return false;
+    else if (addr < ro_space()->top())  return true;
+    else if (addr < ro_space()->end())  return false;
+    else if (addr < rw_space()->top())  return true;
+    else                                return false;
+  }
+
+
+  inline size_t block_size(const HeapWord* addr) const {
+    if (addr < the_space()->top()) {
+      return oop(addr)->size();
+    }
+    else if (addr < the_space()->end()) {
+      assert(addr == the_space()->top(), "non-block head arg to block_size");
+      return the_space()->end() - the_space()->top();
+    }
+
+    else if (addr < ro_space()->top()) {
+      return oop(addr)->size();
+    }
+    else if (addr < ro_space()->end()) {
+      assert(addr == ro_space()->top(), "non-block head arg to block_size");
+      return ro_space()->end() - ro_space()->top();
+    }
+
+    else if (addr < rw_space()->top()) {
+      return oop(addr)->size();
+    }
+    else {
+      assert(addr == rw_space()->top(), "non-block head arg to block_size");
+      return rw_space()->end() - rw_space()->top();
+    }
+  }
+
+  static void generate_vtable_methods(void** vtbl_list,
+                                      void** vtable,
+                                      char** md_top, char* md_end,
+                                      char** mc_top, char* mc_end);
+
+  void verify(bool allow_dirty);
+
+  // Serialization
+  static void initialize_oops() KERNEL_RETURN;
+  static void serialize_oops(SerializeOopClosure* soc);
+  void serialize_bts(SerializeOopClosure* soc);
+
+  // Initiate dumping of shared file.
+  static jint dump_shared(GrowableArray<oop>* class_promote_order, TRAPS);
+
+  // JVM/TI RedefineClasses() support:
+  // Remap the shared readonly space to shared readwrite, private if
+  // sharing is enabled. Simply returns true if sharing is not enabled
+  // or if the remapping has already been done by a prior call.
+  static bool remap_shared_readonly_as_readwrite();
+};