1 /*
   2  * Copyright (c) 2002, 2013, 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_INTERFACE_GCCAUSE_HPP
  26 #define SHARE_VM_GC_INTERFACE_GCCAUSE_HPP
  27 
  28 #include "memory/allocation.hpp"
  29 
  30 //
  31 // This class exposes implementation details of the various
  32 // collector(s), and we need to be very careful with it. If
  33 // use of this class grows, we should split it into public
  34 // and implemenation-private "causes".
  35 //
  36 
  37 class GCCause : public AllStatic {
  38  public:
  39   enum Cause {
  40     /* public */
  41     _java_lang_system_gc,
  42     _full_gc_alot,
  43     _scavenge_alot,
  44     _allocation_profiler,
  45     _jvmti_force_gc,
  46     _gc_locker,
  47     _heap_inspection,
  48     _heap_dump,
  49     _wb_young_gc,
  50     _update_allocation_context_stats_inc,
  51     _update_allocation_context_stats_full,
  52 
  53     /* implementation independent, but reserved for GC use */
  54     _no_gc,
  55     _no_cause_specified,
  56     _allocation_failure,
  57 
  58     /* implementation specific */
  59 
  60     _tenured_generation_full,
  61     _metadata_GC_threshold,
  62 
  63     _cms_generation_full,
  64     _cms_initial_mark,
  65     _cms_final_remark,
  66     _cms_concurrent_mark,
  67 
  68     _old_generation_expanded_on_last_scavenge,
  69     _old_generation_too_full_to_scavenge,
  70     _adaptive_size_policy,
  71 
  72     _g1_inc_collection_pause,
  73     _g1_humongous_allocation,
  74 
  75     _last_ditch_collection,
  76 
  77     _dcmd_gc_run,
  78 
  79     _last_gc_cause
  80   };
  81 
  82   inline static bool is_user_requested_gc(GCCause::Cause cause) {
  83     return (cause == GCCause::_java_lang_system_gc ||
  84             cause == GCCause::_dcmd_gc_run);
  85   }
  86 
  87   inline static bool is_serviceability_requested_gc(GCCause::Cause
  88                                                              cause) {
  89     return (cause == GCCause::_jvmti_force_gc ||
  90             cause == GCCause::_heap_inspection ||
  91             cause == GCCause::_heap_dump);
  92   }
  93 
  94   // Return a string describing the GCCause.
  95   static const char* to_string(GCCause::Cause cause);
  96 };
  97 
  98 // Helper class for doing logging that includes the GC Cause
  99 // as a string.
 100 class GCCauseString : StackObj {
 101  private:
 102    static const int _length = 128;
 103    char _buffer[_length];
 104    int _position;
 105 
 106  public:
 107    GCCauseString(const char* prefix, GCCause::Cause cause) {
 108      if (PrintGCCause) {
 109       _position = jio_snprintf(_buffer, _length, "%s (%s) ", prefix, GCCause::to_string(cause));
 110      } else {
 111       _position = jio_snprintf(_buffer, _length, "%s ", prefix);
 112      }
 113      assert(_position >= 0 && _position <= _length,
 114        err_msg("Need to increase the buffer size in GCCauseString? %d", _position));
 115    }
 116 
 117    GCCauseString& append(const char* str) {
 118      int res = jio_snprintf(_buffer + _position, _length - _position, "%s", str);
 119      _position += res;
 120      assert(res >= 0 && _position <= _length,
 121        err_msg("Need to increase the buffer size in GCCauseString? %d", res));
 122      return *this;
 123    }
 124 
 125    operator const char*() {
 126      return _buffer;
 127    }
 128 };
 129 
 130 #endif // SHARE_VM_GC_INTERFACE_GCCAUSE_HPP