jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/g1/g1CodeCacheRemSet.hpp@2c6ef90f030a (annotated)

src/share/vm/gc_implementation/g1/g1CodeCacheRemSet.hpp@2c6ef90f030a (annotated)

src/share/vm/gc_implementation/g1/g1CodeCacheRemSet.hpp

Mon, 07 Jul 2014 10:12:40 +0200

author: stefank
date: Mon, 07 Jul 2014 10:12:40 +0200
changeset 6992: 2c6ef90f030a
parent 6932: 828056cf311f
child 7208: 7baf47cb97cb
permissions: -rw-r--r--

8049421: G1 Class Unloading after completing a concurrent mark cycle
Reviewed-by: tschatzl, ehelin, brutisso, coleenp, roland, iveresov
Contributed-by: stefan.karlsson@oracle.com, mikael.gerdin@oracle.com

 /*
  * Copyright (c) 2014, 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.
  *
  */
 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1CODECACHEREMSET_HPP
 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1CODECACHEREMSET_HPP
 #include "memory/allocation.hpp"
 #include "memory/freeList.hpp"
 #include "runtime/globals.hpp"
 class CodeBlobClosure;
 // The elements of the G1CodeRootChunk is either:
 //  1) nmethod pointers
 //  2) nodes in an internally chained free list
 typedef union {
   nmethod* _nmethod;
   void*    _link;
 } NmethodOrLink;
 class G1CodeRootChunk : public CHeapObj<mtGC> {
  private:
   static const int NUM_ENTRIES = 32;
  public:
   G1CodeRootChunk*     _next;
   G1CodeRootChunk*     _prev;
   NmethodOrLink*          _top;
   // First free position within the chunk.
   volatile NmethodOrLink* _free;
   NmethodOrLink _data[NUM_ENTRIES];
   NmethodOrLink* bottom() const {
     return (NmethodOrLink*) &(_data[0]);
   }
   NmethodOrLink* end() const {
     return (NmethodOrLink*) &(_data[NUM_ENTRIES]);
   }
   bool is_link(NmethodOrLink* nmethod_or_link) {
     return nmethod_or_link->_link == NULL ||
         (bottom() <= nmethod_or_link->_link
         && nmethod_or_link->_link < end());
   }
   bool is_nmethod(NmethodOrLink* nmethod_or_link) {
     return !is_link(nmethod_or_link);
   }
  public:
   G1CodeRootChunk();
   ~G1CodeRootChunk() {}
   static size_t word_size() { return (size_t)(align_size_up_(sizeof(G1CodeRootChunk), HeapWordSize) / HeapWordSize); }
   // FreeList "interface" methods
   G1CodeRootChunk* next() const         { return _next; }
   G1CodeRootChunk* prev() const         { return _prev; }
   void set_next(G1CodeRootChunk* v)     { _next = v; assert(v != this, "Boom");}
   void set_prev(G1CodeRootChunk* v)     { _prev = v; assert(v != this, "Boom");}
   void clear_next()       { set_next(NULL); }
   void clear_prev()       { set_prev(NULL); }
   size_t size() const { return word_size(); }
   void link_next(G1CodeRootChunk* ptr)  { set_next(ptr); }
   void link_prev(G1CodeRootChunk* ptr)  { set_prev(ptr); }
   void link_after(G1CodeRootChunk* ptr) {
     link_next(ptr);
     if (ptr != NULL) ptr->link_prev((G1CodeRootChunk*)this);
   }
   bool is_free()                 { return true; }
   // New G1CodeRootChunk routines
   void reset();
   bool is_empty() const {
     return _top == bottom();
   }
   bool is_full() const {
     return _top == end() && _free == NULL;
   }
   bool contains(nmethod* method) {
     NmethodOrLink* cur = bottom();
     while (cur != _top) {
       if (cur->_nmethod == method) return true;
       cur++;
     }
     return false;
   }
   bool add(nmethod* method) {
     if (is_full()) {
       return false;
     }
     if (_free != NULL) {
       // Take from internally chained free list
       NmethodOrLink* first_free = (NmethodOrLink*)_free;
       _free = (NmethodOrLink*)_free->_link;
       first_free->_nmethod = method;
     } else {
       // Take from top.
       _top->_nmethod = method;
       _top++;
     }
     return true;
   }
   bool remove_lock_free(nmethod* method);
   void nmethods_do(CodeBlobClosure* blk);
   nmethod* pop() {
     if (_free != NULL) {
       // Kill the free list.
       _free = NULL;
     }
     while (!is_empty()) {
       _top--;
       if (is_nmethod(_top)) {
         return _top->_nmethod;
       }
     }
     return NULL;
   }
 };
 // Manages free chunks.
 class G1CodeRootChunkManager VALUE_OBJ_CLASS_SPEC {
  private:
   // Global free chunk list management
   FreeList<G1CodeRootChunk> _free_list;
   // Total number of chunks handed out
   size_t _num_chunks_handed_out;
  public:
   G1CodeRootChunkManager();
   G1CodeRootChunk* new_chunk();
   void free_chunk(G1CodeRootChunk* chunk);
   // Free all elements of the given list.
   void free_all_chunks(FreeList<G1CodeRootChunk>* list);
   void initialize();
   void purge_chunks(size_t keep_ratio);
   static size_t static_mem_size();
   size_t fl_mem_size();
 #ifndef PRODUCT
   size_t num_chunks_handed_out() const;
   size_t num_free_chunks() const;
 #endif
 };
 // Implements storage for a set of code roots.
 // All methods that modify the set are not thread-safe except if otherwise noted.
 class G1CodeRootSet VALUE_OBJ_CLASS_SPEC {
  private:
   // Global default free chunk manager instance.
   static G1CodeRootChunkManager _default_chunk_manager;
   G1CodeRootChunk* new_chunk() { return _manager->new_chunk(); }
   void free_chunk(G1CodeRootChunk* chunk) { _manager->free_chunk(chunk); }
   // Free all elements of the given list.
   void free_all_chunks(FreeList<G1CodeRootChunk>* list) { _manager->free_all_chunks(list); }
   // Return the chunk that contains the given nmethod, NULL otherwise.
   // Scans the list of chunks backwards, as this method is used to add new
   // entries, which are typically added in bulk for a single nmethod.
   G1CodeRootChunk* find(nmethod* method);
   void free(G1CodeRootChunk* chunk);
   size_t _length;
   FreeList<G1CodeRootChunk> _list;
   G1CodeRootChunkManager* _manager;
  public:
   // If an instance is initialized with a chunk manager of NULL, use the global
   // default one.
   G1CodeRootSet(G1CodeRootChunkManager* manager = NULL);
   ~G1CodeRootSet();
   static void purge_chunks(size_t keep_ratio);
   static size_t free_chunks_static_mem_size();
   static size_t free_chunks_mem_size();
   // Search for the code blob from the recently allocated ones to find duplicates more quickly, as this
   // method is likely to be repeatedly called with the same nmethod.
   void add(nmethod* method);
   void remove_lock_free(nmethod* method);
   nmethod* pop();
   bool contains(nmethod* method);
   void clear();
   void nmethods_do(CodeBlobClosure* blk) const;
   bool is_empty() { return length() == 0; }
   // Length in elements
   size_t length() const { return _length; }
   // Static data memory size in bytes of this set.
   static size_t static_mem_size();
   // Memory size in bytes taken by this set.
   size_t mem_size();
   static void test() PRODUCT_RETURN;
 };
 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1CODECACHEREMSET_HPP

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/gc_implementation/g1/g1CodeCacheRemSet.hpp@2c6ef90f030a (annotated)

src/share/vm/gc_implementation/g1/g1CodeCacheRemSet.hpp