1 /*
   2  * Copyright (c) 2002, 2010, 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_GSPACECOUNTERS_HPP
  26 #define SHARE_VM_GC_IMPLEMENTATION_SHARED_GSPACECOUNTERS_HPP
  27 
  28 #ifndef SERIALGC
  29 #include "gc_implementation/shared/generationCounters.hpp"
  30 #include "memory/generation.hpp"
  31 #include "runtime/perfData.hpp"
  32 #endif
  33 
  34 // A GSpaceCounter is a holder class for performance counters
  35 // that track a space;
  36 
  37 class GSpaceCounters: public CHeapObj {
  38   friend class VMStructs;
  39 
  40  private:
  41   PerfVariable*      _capacity;
  42   PerfVariable*      _used;
  43 
  44   // Constant PerfData types don't need to retain a reference.
  45   // However, it's a good idea to document them here.
  46   // PerfConstant*     _size;
  47 
  48   Generation*       _gen;
  49   char*             _name_space;
  50 
  51  public:
  52 
  53   GSpaceCounters(const char* name, int ordinal, size_t max_size, Generation* g,
  54                  GenerationCounters* gc, bool sampled=true);
  55 
  56   ~GSpaceCounters() {
  57     if (_name_space != NULL) FREE_C_HEAP_ARRAY(char, _name_space);
  58   }
  59 
  60   inline void update_capacity() {
  61     _capacity->set_value(_gen->capacity());
  62   }
  63 
  64   inline void update_used() {
  65     _used->set_value(_gen->used());
  66   }
  67 
  68   // special version of update_used() to allow the used value to be
  69   // passed as a parameter. This method can can be used in cases were
  70   // the  utilization is already known and/or when the _gen->used()
  71   // method is known to be expensive and we want to avoid unnecessary
  72   // calls to it.
  73   //
  74   inline void update_used(size_t used) {
  75     _used->set_value(used);
  76   }
  77 
  78   inline void inc_used(size_t size) {
  79     _used->inc(size);
  80   }
  81 
  82   debug_only(
  83     // for security reasons, we do not allow arbitrary reads from
  84     // the counters as they may live in shared memory.
  85     jlong used() {
  86       return _used->get_value();
  87     }
  88     jlong capacity() {
  89       return _used->get_value();
  90     }
  91   )
  92 
  93   inline void update_all() {
  94     update_used();
  95     update_capacity();
  96   }
  97 
  98   const char* name_space() const        { return _name_space; }
  99 };
 100 
 101 class GenerationUsedHelper : public PerfLongSampleHelper {
 102   private:
 103     Generation* _gen;
 104 
 105   public:
 106     GenerationUsedHelper(Generation* g) : _gen(g) { }
 107 
 108     inline jlong take_sample() {
 109       return _gen->used();
 110     }
 111 };
 112 
 113 #endif // SHARE_VM_GC_IMPLEMENTATION_SHARED_GSPACECOUNTERS_HPP