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 implementation-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     _wb_conc_mark,
  51     _update_allocation_context_stats_inc,
  52     _update_allocation_context_stats_full,
  53 
  54     /* implementation independent, but reserved for GC use */
  55     _no_gc,
  56     _no_cause_specified,
  57     _allocation_failure,
  58 
  59     /* implementation specific */
  60 
  61     _tenured_generation_full,
  62     _metadata_GC_threshold,
  63 
  64     _cms_generation_full,
  65     _cms_initial_mark,
  66     _cms_final_remark,
  67     _cms_concurrent_mark,
  68 
  69     _old_generation_expanded_on_last_scavenge,
  70     _old_generation_too_full_to_scavenge,
  71     _adaptive_size_policy,
  72 
  73     _g1_inc_collection_pause,
  74     _g1_humongous_allocation,
  75 
  76     _last_ditch_collection,
  77 
  78     _dcmd_gc_run,
  79 
  80     _last_gc_cause
  81   };
  82 
  83   inline static bool is_user_requested_gc(GCCause::Cause cause) {
  84     return (cause == GCCause::_java_lang_system_gc ||
  85             cause == GCCause::_dcmd_gc_run);
  86   }
  87 
  88   inline static bool is_serviceability_requested_gc(GCCause::Cause
  89                                                              cause) {
  90     return (cause == GCCause::_jvmti_force_gc ||
  91             cause == GCCause::_heap_inspection ||
  92             cause == GCCause::_heap_dump);
  93   }
  94 
  95   // Return a string describing the GCCause.
  96   static const char* to_string(GCCause::Cause cause);
  97 };
  98 
  99 // Helper class for doing logging that includes the GC Cause
 100 // as a string.
 101 class GCCauseString : StackObj {
 102  private:
 103    static const int _length = 128;
 104    char _buffer[_length];
 105    int _position;
 106 
 107  public:
 108    GCCauseString(const char* prefix, GCCause::Cause cause) {
 109      if (PrintGCCause) {
 110       _position = jio_snprintf(_buffer, _length, "%s (%s) ", prefix, GCCause::to_string(cause));
 111      } else {
 112       _position = jio_snprintf(_buffer, _length, "%s ", prefix);
 113      }
 114      assert(_position >= 0 && _position <= _length,
 115        err_msg("Need to increase the buffer size in GCCauseString? %d", _position));
 116    }
 117 
 118    GCCauseString& append(const char* str) {
 119      int res = jio_snprintf(_buffer + _position, _length - _position, "%s", str);
 120      _position += res;
 121      assert(res >= 0 && _position <= _length,
 122        err_msg("Need to increase the buffer size in GCCauseString? %d", res));
 123      return *this;
 124    }
 125 
 126    operator const char*() {
 127      return _buffer;
 128    }
 129 };
 130 
 131 #endif // SHARE_VM_GC_INTERFACE_GCCAUSE_HPP