1 /*

     2  * Copyright (c) 2002, 2019, 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_GC_CMS_GSPACECOUNTERS_HPP

    26 #define SHARE_GC_CMS_GSPACECOUNTERS_HPP

    27 

    28 #include "gc/shared/generation.hpp"

    29 #include "gc/shared/generationCounters.hpp"

    30 #include "runtime/perfData.hpp"

    31 #include "utilities/macros.hpp"

    32 

    33 // A GSpaceCounter is a holder class for performance counters

    34 // that track a space;

    35 

    36 class GSpaceCounters: public CHeapObj<mtGC> {

    37   friend class VMStructs;

    38 

    39  private:

    40   PerfVariable*      _capacity;

    41   PerfVariable*      _used;

    42 

    43   // Constant PerfData types don't need to retain a reference.

    44   // However, it's a good idea to document them here.

    45   // PerfConstant*     _size;

    46 

    47   Generation*       _gen;

    48   char*             _name_space;

    49 

    50  public:

    51 

    52   GSpaceCounters(const char* name, int ordinal, size_t max_size, Generation* g,

    53                  GenerationCounters* gc, bool sampled=true);

    54 

    55   ~GSpaceCounters();

    56 

    57   inline void update_capacity() {

    58     _capacity->set_value(_gen->capacity());

    59   }

    60 

    61   inline void update_used() {

    62     _used->set_value(_gen->used_stable());

    63   }

    64 

    65   // special version of update_used() to allow the used value to be

    66   // passed as a parameter. This method can can be used in cases were

    67   // the  utilization is already known and/or when the _gen->used()

    68   // method is known to be expensive and we want to avoid unnecessary

    69   // calls to it.

    70   //

    71   inline void update_used(size_t used) {

    72     _used->set_value(used);

    73   }

    74 

    75   inline void inc_used(size_t size) {

    76     _used->inc(size);

    77   }

    78 

    79   debug_only(

    80     // for security reasons, we do not allow arbitrary reads from

    81     // the counters as they may live in shared memory.

    82     jlong used() {

    83       return _used->get_value();

    84     }

    85     jlong capacity() {

    86       return _used->get_value();

    87     }

    88   )

    89 

    90   inline void update_all() {

    91     update_used();

    92     update_capacity();

    93   }

    94 

    95   const char* name_space() const        { return _name_space; }

    96 };

    97 

    98 class GenerationUsedHelper : public PerfLongSampleHelper {

    99   private:

   100     Generation* _gen;

   101 

   102   public:

   103     GenerationUsedHelper(Generation* g) : _gen(g) { }

   104 

   105     inline jlong take_sample() {

   106       return _gen->used_stable();

   107     }

   108 };

   109 

   110 #endif // SHARE_GC_CMS_GSPACECOUNTERS_HPP