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 *

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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

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#include "memory/allocation.hpp"

#include "utilities/debug.hpp"

// The log of G1's heuristic decisions comprises of a series of

// records which have a similar format in order to maintain

// consistency across records and ultimately easier parsing of the

// output, if we ever choose to do that. Each record consists of:

// * A time stamp to be able to easily correlate each record with

// other events.

// * A unique string to allow us to easily identify such records.

// * The name of the heuristic the record corresponds to.

// * An action string which describes the action that G1 did or is

// about to do.

// * An optional reason string which describes the reason for the

// action.

// * An optional number of name/value pairs which contributed to the

// decision to take the action described in the record.

//

// Each record is associated with a "tag" which is the combination of

// the heuristic the record corresponds to, as well as the min level

// of verboseness at which the record should be printed. The tag is

// checked against the current settings to determine whether the record

// should be printed or not.

// The available verboseness levels.

typedef enum {

  // Determine which part of the tag is occupied by the level.

  ErgoLevelShift = 8,

  ErgoLevelMask = ~((1 << ErgoLevelShift) - 1),

  // ErgoLow is 0 so that we don't have to explicitly or a heuristic

  // id with ErgoLow to keep its use simpler.

  ErgoLow = 0,

  ErgoHigh = 1 << ErgoLevelShift

} ErgoLevel;

// The available heuristics.

typedef enum {

  // Determines which part of the tag is occupied by the heuristic id.

  ErgoHeuristicMask = ~ErgoLevelMask,

  ErgoHeapSizing = 0,

  ErgoCSetConstruction,

  ErgoConcCycles,

  ErgoMixedGCs,

  ErgoHeuristicNum

} ErgoHeuristic;

class G1ErgoVerbose : AllStatic {

private:

  // Determines the minimum verboseness level at which records will be

  // printed.

  static ErgoLevel _level;

  // Determines which heuristics are currently enabled.

  static bool _enabled[ErgoHeuristicNum];

  static ErgoLevel extract_level(int tag) {

    return (ErgoLevel) (tag & ErgoLevelMask);

  }

  static ErgoHeuristic extract_heuristic(int tag) {

    return (ErgoHeuristic) (tag & ErgoHeuristicMask);

  }

public:

  // Needs to be explicitly called at GC initialization.

  static void initialize();

  static void set_level(ErgoLevel level);

  static void set_enabled(ErgoHeuristic h, bool enabled);

  // It is applied to all heuristics.

  static void set_enabled(bool enabled);

  static bool enabled(int tag) {

    ErgoLevel level = extract_level(tag);

    ErgoHeuristic n = extract_heuristic(tag);

    return level <= _level && _enabled[n];

  }

  // Extract the heuristic id from the tag and return a string with

  // its name.

  static const char* to_string(int tag);

};

// The macros below generate the format string for values of different

// types and/or metrics.

// The reason for the action is optional and is handled specially: the

// reason string is concatenated here so it's not necessary to pass it

// as a parameter.

#define ergo_format_reason(_reason_) ", reason: " _reason_

// Single parameter format strings

#define ergo_format_str(_name_)      ", " _name_ ": %s"

#define ergo_format_region(_name_)   ", " _name_ ": %u regions"

#define ergo_format_byte(_name_)     ", " _name_ ": "SIZE_FORMAT" bytes"

#define ergo_format_double(_name_)   ", " _name_ ": %1.2f"

#define ergo_format_perc(_name_)     ", " _name_ ": %1.2f %%"

#define ergo_format_ms(_name_)       ", " _name_ ": %1.2f ms"

#define ergo_format_size(_name_)     ", " _name_ ": "SIZE_FORMAT

// Double parameter format strings

#define ergo_format_byte_perc(_name_)                                   \

                             ", " _name_ ": "SIZE_FORMAT" bytes (%1.2f %%)"

// Generates the format string

#define ergo_format(_extra_format_)                           \

  " %1.3f: [G1Ergonomics (%s) %s" _extra_format_ "]"

// Conditionally, prints an ergonomic decision record. _extra_format_

// is the format string for the optional items we'd like to print

// (i.e., the decision's reason and any associated values). This

// string should be built up using the ergo_*_format macros (see

// above) to ensure consistency.

//

// Since we cannot rely on the compiler supporting variable argument

// macros, this macro accepts a fixed number of arguments and passes

// them to the print method. For convenience, we have wrapper macros

// below which take a specific number of arguments and set the rest to

// a default value.

#define ergo_verbose_common(_tag_, _action_, _extra_format_,                \

                            _arg0_, _arg1_, _arg2_, _arg3_, _arg4_, _arg5_) \

  do {                                                                      \

    if (G1ErgoVerbose::enabled((_tag_))) {                                  \

      gclog_or_tty->print_cr(ergo_format(_extra_format_),                   \

                             os::elapsedTime(),                             \

                             G1ErgoVerbose::to_string((_tag_)),             \

                             (_action_),                                    \

                             (_arg0_), (_arg1_), (_arg2_),                  \

                             (_arg3_), (_arg4_), (_arg5_));                 \

    }                                                                       \

  } while (0)

#define ergo_verbose6(_tag_, _action_, _extra_format_,                  \

                      _arg0_, _arg1_, _arg2_, _arg3_, _arg4_, _arg5_)   \

  ergo_verbose_common(_tag_, _action_, _extra_format_,                  \

                      _arg0_, _arg1_, _arg2_, _arg3_, _arg4_, _arg5_)

#define ergo_verbose5(_tag_, _action_, _extra_format_,                  \

                      _arg0_, _arg1_, _arg2_, _arg3_, _arg4_)           \

  ergo_verbose6(_tag_, _action_, _extra_format_ "%s",                   \

                _arg0_, _arg1_, _arg2_, _arg3_, _arg4_, "")

#define ergo_verbose4(_tag_, _action_, _extra_format_,                  \

                      _arg0_, _arg1_, _arg2_, _arg3_)                   \

  ergo_verbose5(_tag_, _action_, _extra_format_ "%s",                   \

                _arg0_, _arg1_, _arg2_, _arg3_, "")

#define ergo_verbose3(_tag_, _action_, _extra_format_,                  \

                      _arg0_, _arg1_, _arg2_)                           \

  ergo_verbose4(_tag_, _action_, _extra_format_ "%s",                   \

                _arg0_, _arg1_, _arg2_, "")

#define ergo_verbose2(_tag_, _action_, _extra_format_,                  \

                      _arg0_, _arg1_)                                   \

  ergo_verbose3(_tag_, _action_, _extra_format_ "%s",                   \

                _arg0_, _arg1_, "")

#define ergo_verbose1(_tag_, _action_, _extra_format_,                  \

                      _arg0_)                                           \

  ergo_verbose2(_tag_, _action_, _extra_format_ "%s",                   \

                _arg0_, "")

#define ergo_verbose0(_tag_, _action_, _extra_format_)                  \

  ergo_verbose1(_tag_, _action_, _extra_format_ "%s",                   \

                "")

#define ergo_verbose(_tag_, _action_)                                   \

  ergo_verbose0(_tag_, _action_, "")