1 /*
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   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
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  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).
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  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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  24 
  25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1ERGOVERBOSE_HPP
  26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1ERGOVERBOSE_HPP
  27 
  28 #include "memory/allocation.hpp"
  29 #include "utilities/debug.hpp"
  30 
  31 // The log of G1's heuristic decisions comprises of a series of
  32 // records which have a similar format in order to maintain
  33 // consistency across records and ultimately easier parsing of the
  34 // output, if we ever choose to do that. Each record consists of:
  35 // * A time stamp to be able to easily correlate each record with
  36 // other events.
  37 // * A unique string to allow us to easily identify such records.
  38 // * The name of the heuristic the record corresponds to.
  39 // * An action string which describes the action that G1 did or is
  40 // about to do.
  41 // * An optional reason string which describes the reason for the
  42 // action.
  43 // * An optional number of name/value pairs which contributed to the
  44 // decision to take the action described in the record.
  45 //
  46 // Each record is associated with a "tag" which is the combination of
  47 // the heuristic the record corresponds to, as well as the min level
  48 // of verboseness at which the record should be printed. The tag is
  49 // checked against the current settings to determine whether the record
  50 // should be printed or not.
  51 
  52 // The available verboseness levels.
  53 typedef enum {
  54   // Determine which part of the tag is occupied by the level.
  55   ErgoLevelShift = 8,
  56   ErgoLevelMask = ~((1 << ErgoLevelShift) - 1),
  57 
  58   // ErgoLow is 0 so that we don't have to explicitly or a heuristic
  59   // id with ErgoLow to keep its use simpler.
  60   ErgoLow = 0,
  61   ErgoHigh = 1 << ErgoLevelShift
  62 } ErgoLevel;
  63 
  64 // The available heuristics.
  65 typedef enum {
  66   // Determines which part of the tag is occupied by the heuristic id.
  67   ErgoHeuristicMask = ~ErgoLevelMask,
  68 
  69   ErgoHeapSizing = 0,
  70   ErgoCSetConstruction,
  71   ErgoConcCycles,
  72   ErgoMixedGCs,
  73 
  74   ErgoHeuristicNum
  75 } ErgoHeuristic;
  76 
  77 class G1ErgoVerbose : AllStatic {
  78 private:
  79   // Determines the minimum verboseness level at which records will be
  80   // printed.
  81   static ErgoLevel _level;
  82   // Determines which heuristics are currently enabled.
  83   static bool _enabled[ErgoHeuristicNum];
  84 
  85   static ErgoLevel extract_level(int tag) {
  86     return (ErgoLevel) (tag & ErgoLevelMask);
  87   }
  88 
  89   static ErgoHeuristic extract_heuristic(int tag) {
  90     return (ErgoHeuristic) (tag & ErgoHeuristicMask);
  91   }
  92 
  93 public:
  94   // Needs to be explicitly called at GC initialization.
  95   static void initialize();
  96 
  97   static void set_level(ErgoLevel level);
  98   static void set_enabled(ErgoHeuristic h, bool enabled);
  99   // It is applied to all heuristics.
 100   static void set_enabled(bool enabled);
 101 
 102   static bool enabled(int tag) {
 103     ErgoLevel level = extract_level(tag);
 104     ErgoHeuristic n = extract_heuristic(tag);
 105     return level <= _level && _enabled[n];
 106   }
 107 
 108   // Extract the heuristic id from the tag and return a string with
 109   // its name.
 110   static const char* to_string(int tag);
 111 };
 112 
 113 // The macros below generate the format string for values of different
 114 // types and/or metrics.
 115 
 116 // The reason for the action is optional and is handled specially: the
 117 // reason string is concatenated here so it's not necessary to pass it
 118 // as a parameter.
 119 #define ergo_format_reason(_reason_) ", reason: " _reason_
 120 
 121 // Single parameter format strings
 122 #define ergo_format_str(_name_)      ", " _name_ ": %s"
 123 #define ergo_format_region(_name_)   ", " _name_ ": %u regions"
 124 #define ergo_format_byte(_name_)     ", " _name_ ": "SIZE_FORMAT" bytes"
 125 #define ergo_format_double(_name_)   ", " _name_ ": %1.2f"
 126 #define ergo_format_perc(_name_)     ", " _name_ ": %1.2f %%"
 127 #define ergo_format_ms(_name_)       ", " _name_ ": %1.2f ms"
 128 #define ergo_format_size(_name_)     ", " _name_ ": "SIZE_FORMAT
 129 
 130 // Double parameter format strings
 131 #define ergo_format_byte_perc(_name_)                                   \
 132                              ", " _name_ ": "SIZE_FORMAT" bytes (%1.2f %%)"
 133 
 134 // Generates the format string
 135 #define ergo_format(_extra_format_)                           \
 136   " %1.3f: [G1Ergonomics (%s) %s" _extra_format_ "]"
 137 
 138 // Conditionally, prints an ergonomic decision record. _extra_format_
 139 // is the format string for the optional items we'd like to print
 140 // (i.e., the decision's reason and any associated values). This
 141 // string should be built up using the ergo_*_format macros (see
 142 // above) to ensure consistency.
 143 //
 144 // Since we cannot rely on the compiler supporting variable argument
 145 // macros, this macro accepts a fixed number of arguments and passes
 146 // them to the print method. For convenience, we have wrapper macros
 147 // below which take a specific number of arguments and set the rest to
 148 // a default value.
 149 #define ergo_verbose_common(_tag_, _action_, _extra_format_,                \
 150                             _arg0_, _arg1_, _arg2_, _arg3_, _arg4_, _arg5_) \
 151   do {                                                                      \
 152     if (G1ErgoVerbose::enabled((_tag_))) {                                  \
 153       gclog_or_tty->print_cr(ergo_format(_extra_format_),                   \
 154                              os::elapsedTime(),                             \
 155                              G1ErgoVerbose::to_string((_tag_)),             \
 156                              (_action_),                                    \
 157                              (_arg0_), (_arg1_), (_arg2_),                  \
 158                              (_arg3_), (_arg4_), (_arg5_));                 \
 159     }                                                                       \
 160   } while (0)
 161 
 162 
 163 #define ergo_verbose6(_tag_, _action_, _extra_format_,                  \
 164                       _arg0_, _arg1_, _arg2_, _arg3_, _arg4_, _arg5_)   \
 165   ergo_verbose_common(_tag_, _action_, _extra_format_,                  \
 166                       _arg0_, _arg1_, _arg2_, _arg3_, _arg4_, _arg5_)
 167 
 168 #define ergo_verbose5(_tag_, _action_, _extra_format_,                  \
 169                       _arg0_, _arg1_, _arg2_, _arg3_, _arg4_)           \
 170   ergo_verbose6(_tag_, _action_, _extra_format_ "%s",                   \
 171                 _arg0_, _arg1_, _arg2_, _arg3_, _arg4_, "")
 172 
 173 #define ergo_verbose4(_tag_, _action_, _extra_format_,                  \
 174                       _arg0_, _arg1_, _arg2_, _arg3_)                   \
 175   ergo_verbose5(_tag_, _action_, _extra_format_ "%s",                   \
 176                 _arg0_, _arg1_, _arg2_, _arg3_, "")
 177 
 178 #define ergo_verbose3(_tag_, _action_, _extra_format_,                  \
 179                       _arg0_, _arg1_, _arg2_)                           \
 180   ergo_verbose4(_tag_, _action_, _extra_format_ "%s",                   \
 181                 _arg0_, _arg1_, _arg2_, "")
 182 
 183 #define ergo_verbose2(_tag_, _action_, _extra_format_,                  \
 184                       _arg0_, _arg1_)                                   \
 185   ergo_verbose3(_tag_, _action_, _extra_format_ "%s",                   \
 186                 _arg0_, _arg1_, "")
 187 
 188 #define ergo_verbose1(_tag_, _action_, _extra_format_,                  \
 189                       _arg0_)                                           \
 190   ergo_verbose2(_tag_, _action_, _extra_format_ "%s",                   \
 191                 _arg0_, "")
 192 
 193 
 194 #define ergo_verbose0(_tag_, _action_, _extra_format_)                  \
 195   ergo_verbose1(_tag_, _action_, _extra_format_ "%s",                   \
 196                 "")
 197 
 198 #define ergo_verbose(_tag_, _action_)                                   \
 199   ergo_verbose0(_tag_, _action_, "")
 200 
 201 
 202 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1ERGOVERBOSE_HPP