1 /*
   2  * Copyright (c) 2011, 2014, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_GC_IMPLEMENTATION_SHARED_HSPACECOUNTERS_HPP
  26 #define SHARE_VM_GC_IMPLEMENTATION_SHARED_HSPACECOUNTERS_HPP
  27 
  28 #include "utilities/macros.hpp"
  29 #include "gc_implementation/shared/generationCounters.hpp"
  30 #include "memory/generation.hpp"
  31 #include "runtime/perfData.hpp"
  32 
  33 // A HSpaceCounter is a holder class for performance counters
  34 // that track a collections (logical spaces) in a heap;
  35 
  36 class HeapSpaceUsedHelper;
  37 class G1SpaceMonitoringSupport;
  38 
  39 class HSpaceCounters: public CHeapObj<mtGC> {
  40   friend class VMStructs;
  41 
  42  private:
  43   PerfVariable*        _capacity;
  44   PerfVariable*        _used;
  45 
  46   // Constant PerfData types don't need to retain a reference.
  47   // However, it's a good idea to document them here.
  48 
  49   char*             _name_space;
  50 
  51  public:
  52 
  53   HSpaceCounters(const char* name, int ordinal, size_t max_size,
  54                  size_t initial_capacity, GenerationCounters* gc);
  55 
  56   ~HSpaceCounters() {
  57     if (_name_space != NULL) FREE_C_HEAP_ARRAY(char, _name_space);
  58   }
  59 
  60   inline void update_capacity(size_t v) {
  61     _capacity->set_value(v);
  62   }
  63 
  64   inline void update_used(size_t v) {
  65     _used->set_value(v);
  66   }
  67 
  68   debug_only(
  69     // for security reasons, we do not allow arbitrary reads from
  70     // the counters as they may live in shared memory.
  71     jlong used() {
  72       return _used->get_value();
  73     }
  74     jlong capacity() {
  75       return _used->get_value();
  76     }
  77   )
  78 
  79   inline void update_all(size_t capacity, size_t used) {
  80     update_capacity(capacity);
  81     update_used(used);
  82   }
  83 
  84   const char* name_space() const        { return _name_space; }
  85 };
  86 #endif // SHARE_VM_GC_IMPLEMENTATION_SHARED_HSPACECOUNTERS_HPP