/*

 * Copyright (c) 2013, 2015, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * 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.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "gc/g1/g1CollectedHeap.inline.hpp"

#include "gc/g1/g1GCPhaseTimes.hpp"

#include "gc/g1/g1Log.hpp"

#include "gc/g1/g1StringDedup.hpp"

#include "memory/allocation.hpp"

#include "runtime/os.hpp"

// Helper class for avoiding interleaved logging

class LineBuffer: public StackObj {

private:

  static const int BUFFER_LEN = 1024;

  static const int INDENT_CHARS = 3;

  char _buffer[BUFFER_LEN];

  int _indent_level;

  int _cur;

  void vappend(const char* format, va_list ap)  ATTRIBUTE_PRINTF(2, 0) {

    int res = vsnprintf(&_buffer[_cur], BUFFER_LEN - _cur, format, ap);

    if (res != -1) {

      _cur += res;

    } else {

      DEBUG_ONLY(warning("buffer too small in LineBuffer");)

      _buffer[BUFFER_LEN -1] = 0;

      _cur = BUFFER_LEN; // vsnprintf above should not add to _buffer if we are called again

    }

  }

public:

  explicit LineBuffer(int indent_level): _indent_level(indent_level), _cur(0) {

    for (; (_cur < BUFFER_LEN && _cur < (_indent_level * INDENT_CHARS)); _cur++) {

      _buffer[_cur] = ' ';

    }

  }

#ifndef PRODUCT

  ~LineBuffer() {

    assert(_cur == _indent_level * INDENT_CHARS, "pending data in buffer - append_and_print_cr() not called?");

  }

#endif

  void append(const char* format, ...)  ATTRIBUTE_PRINTF(2, 3) {

    va_list ap;

    va_start(ap, format);

    vappend(format, ap);

    va_end(ap);

  }

  void print_cr() {

    gclog_or_tty->print_cr("%s", _buffer);

    _cur = _indent_level * INDENT_CHARS;

  }

  void append_and_print_cr(const char* format, ...)  ATTRIBUTE_PRINTF(2, 3) {

    va_list ap;

    va_start(ap, format);

    vappend(format, ap);

    va_end(ap);

    print_cr();

  }

};

template <class T>

class WorkerDataArray  : public CHeapObj<mtGC> {

  friend class G1GCParPhasePrinter;

  T*          _data;

  uint        _length;

  const char* _title;

  bool        _print_sum;

  int         _log_level;

  uint        _indent_level;

  bool        _enabled;

  WorkerDataArray<size_t>* _thread_work_items;

  NOT_PRODUCT(T uninitialized();)

  // We are caching the sum and average to only have to calculate them once.

  // This is not done in an MT-safe way. It is intended to allow single

  // threaded code to call sum() and average() multiple times in any order

  // without having to worry about the cost.

  bool   _has_new_data;

  T      _sum;

  T      _min;

  T      _max;

  double _average;

 public:

  WorkerDataArray(uint length, const char* title, bool print_sum, int log_level, uint indent_level) :

    _title(title), _length(0), _print_sum(print_sum), _log_level(log_level), _indent_level(indent_level),

    _has_new_data(true), _thread_work_items(NULL), _enabled(true) {

    assert(length > 0, "Must have some workers to store data for");

    _length = length;

    _data = NEW_C_HEAP_ARRAY(T, _length, mtGC);

  }

  ~WorkerDataArray() {

    FREE_C_HEAP_ARRAY(T, _data);

  }

  void link_thread_work_items(WorkerDataArray<size_t>* thread_work_items) {

    _thread_work_items = thread_work_items;

  }

  WorkerDataArray<size_t>* thread_work_items() { return _thread_work_items; }

  void set(uint worker_i, T value) {

    _data[worker_i] = value;

    _has_new_data = true;

  }

  void set_thread_work_item(uint worker_i, size_t value) {

    assert(_thread_work_items != NULL, "No sub count");

    _thread_work_items->set(worker_i, value);

  }

  T get(uint worker_i) {

    return _data[worker_i];

  }

  void add(uint worker_i, T value) {

    _data[worker_i] += value;

    _has_new_data = true;

  }

  double average(uint active_threads){

    calculate_totals(active_threads);

    return _average;

  }

  T sum(uint active_threads) {

    calculate_totals(active_threads);

    return _sum;

  }

  T minimum(uint active_threads) {

    calculate_totals(active_threads);

    return _min;

  }

  T maximum(uint active_threads) {

    calculate_totals(active_threads);

    return _max;

  }

  void reset() PRODUCT_RETURN;

  void verify(uint active_threads) PRODUCT_RETURN;

  void set_enabled(bool enabled) { _enabled = enabled; }

  int log_level() { return _log_level;  }

 private:

  void calculate_totals(uint active_threads){

    if (!_has_new_data) {

      return;

    }

    _sum = (T)0;

    _min = _data[0];

    _max = _min;

    assert(active_threads <= _length, "Wrong number of active threads");

    for (uint i = 0; i < active_threads; ++i) {

      T val = _data[i];

      _sum += val;

      _min = MIN2(_min, val);

      _max = MAX2(_max, val);

    }

    _average = (double)_sum / (double)active_threads;

    _has_new_data = false;

  }

};

#ifndef PRODUCT

template <>

size_t WorkerDataArray<size_t>::uninitialized() {

  return (size_t)-1;

}

template <>

double WorkerDataArray<double>::uninitialized() {

  return -1.0;

}

template <class T>

void WorkerDataArray<T>::reset() {

  for (uint i = 0; i < _length; i++) {

    _data[i] = WorkerDataArray<T>::uninitialized();

  }

  if (_thread_work_items != NULL) {

    _thread_work_items->reset();

  }

}

template <class T>

void WorkerDataArray<T>::verify(uint active_threads) {

  if (!_enabled) {

    return;

  }

  assert(active_threads <= _length, "Wrong number of active threads");

  for (uint i = 0; i < active_threads; i++) {

    assert(_data[i] != WorkerDataArray<T>::uninitialized(),

  }

  if (_thread_work_items != NULL) {

    _thread_work_items->verify(active_threads);

  }

}

#endif

G1GCPhaseTimes::G1GCPhaseTimes(uint max_gc_threads) :

  _max_gc_threads(max_gc_threads)

{

  assert(max_gc_threads > 0, "Must have some GC threads");

  _gc_par_phases[GCWorkerStart] = new WorkerDataArray<double>(max_gc_threads, "GC Worker Start (ms)", false, G1Log::LevelFiner, 2);

  _gc_par_phases[ExtRootScan] = new WorkerDataArray<double>(max_gc_threads, "Ext Root Scanning (ms)", true, G1Log::LevelFiner, 2);

  // Root scanning phases

  _gc_par_phases[ThreadRoots] = new WorkerDataArray<double>(max_gc_threads, "Thread Roots (ms)", true, G1Log::LevelFinest, 3);

  _gc_par_phases[StringTableRoots] = new WorkerDataArray<double>(max_gc_threads, "StringTable Roots (ms)", true, G1Log::LevelFinest, 3);

  _gc_par_phases[UniverseRoots] = new WorkerDataArray<double>(max_gc_threads, "Universe Roots (ms)", true, G1Log::LevelFinest, 3);

  _gc_par_phases[JNIRoots] = new WorkerDataArray<double>(max_gc_threads, "JNI Handles Roots (ms)", true, G1Log::LevelFinest, 3);

  _gc_par_phases[ObjectSynchronizerRoots] = new WorkerDataArray<double>(max_gc_threads, "ObjectSynchronizer Roots (ms)", true, G1Log::LevelFinest, 3);

  _gc_par_phases[FlatProfilerRoots] = new WorkerDataArray<double>(max_gc_threads, "FlatProfiler Roots (ms)", true, G1Log::LevelFinest, 3);

  _gc_par_phases[ManagementRoots] = new WorkerDataArray<double>(max_gc_threads, "Management Roots (ms)", true, G1Log::LevelFinest, 3);

  _gc_par_phases[SystemDictionaryRoots] = new WorkerDataArray<double>(max_gc_threads, "SystemDictionary Roots (ms)", true, G1Log::LevelFinest, 3);

  _gc_par_phases[CLDGRoots] = new WorkerDataArray<double>(max_gc_threads, "CLDG Roots (ms)", true, G1Log::LevelFinest, 3);

  _gc_par_phases[JVMTIRoots] = new WorkerDataArray<double>(max_gc_threads, "JVMTI Roots (ms)", true, G1Log::LevelFinest, 3);

  _gc_par_phases[CMRefRoots] = new WorkerDataArray<double>(max_gc_threads, "CM RefProcessor Roots (ms)", true, G1Log::LevelFinest, 3);

  _gc_par_phases[WaitForStrongCLD] = new WorkerDataArray<double>(max_gc_threads, "Wait For Strong CLD (ms)", true, G1Log::LevelFinest, 3);

  _gc_par_phases[WeakCLDRoots] = new WorkerDataArray<double>(max_gc_threads, "Weak CLD Roots (ms)", true, G1Log::LevelFinest, 3);

  _gc_par_phases[SATBFiltering] = new WorkerDataArray<double>(max_gc_threads, "SATB Filtering (ms)", true, G1Log::LevelFinest, 3);

  _gc_par_phases[UpdateRS] = new WorkerDataArray<double>(max_gc_threads, "Update RS (ms)", true, G1Log::LevelFiner, 2);

  _gc_par_phases[ScanRS] = new WorkerDataArray<double>(max_gc_threads, "Scan RS (ms)", true, G1Log::LevelFiner, 2);

  _gc_par_phases[CodeRoots] = new WorkerDataArray<double>(max_gc_threads, "Code Root Scanning (ms)", true, G1Log::LevelFiner, 2);

  _gc_par_phases[ObjCopy] = new WorkerDataArray<double>(max_gc_threads, "Object Copy (ms)", true, G1Log::LevelFiner, 2);

  _gc_par_phases[Termination] = new WorkerDataArray<double>(max_gc_threads, "Termination (ms)", true, G1Log::LevelFiner, 2);

  _gc_par_phases[GCWorkerTotal] = new WorkerDataArray<double>(max_gc_threads, "GC Worker Total (ms)", true, G1Log::LevelFiner, 2);

  _gc_par_phases[GCWorkerEnd] = new WorkerDataArray<double>(max_gc_threads, "GC Worker End (ms)", false, G1Log::LevelFiner, 2);

  _gc_par_phases[Other] = new WorkerDataArray<double>(max_gc_threads, "GC Worker Other (ms)", true, G1Log::LevelFiner, 2);

  _update_rs_processed_buffers = new WorkerDataArray<size_t>(max_gc_threads, "Processed Buffers", true, G1Log::LevelFiner, 3);

  _gc_par_phases[UpdateRS]->link_thread_work_items(_update_rs_processed_buffers);

  _termination_attempts = new WorkerDataArray<size_t>(max_gc_threads, "Termination Attempts", true, G1Log::LevelFinest, 3);

  _gc_par_phases[Termination]->link_thread_work_items(_termination_attempts);

  _gc_par_phases[StringDedupQueueFixup] = new WorkerDataArray<double>(max_gc_threads, "Queue Fixup (ms)", true, G1Log::LevelFiner, 2);

  _gc_par_phases[StringDedupTableFixup] = new WorkerDataArray<double>(max_gc_threads, "Table Fixup (ms)", true, G1Log::LevelFiner, 2);

  _gc_par_phases[RedirtyCards] = new WorkerDataArray<double>(max_gc_threads, "Parallel Redirty", true, G1Log::LevelFinest, 3);

  _redirtied_cards = new WorkerDataArray<size_t>(max_gc_threads, "Redirtied Cards", true, G1Log::LevelFinest, 3);

  _gc_par_phases[RedirtyCards]->link_thread_work_items(_redirtied_cards);

}

void G1GCPhaseTimes::note_gc_start(uint active_gc_threads, bool mark_in_progress) {

  assert(active_gc_threads > 0, "The number of threads must be > 0");

  assert(active_gc_threads <= _max_gc_threads, "The number of active threads must be <= the max number of threads");

  _active_gc_threads = active_gc_threads;

  for (int i = 0; i < GCParPhasesSentinel; i++) {

    _gc_par_phases[i]->reset();

  }

  _gc_par_phases[StringDedupQueueFixup]->set_enabled(G1StringDedup::is_enabled());

  _gc_par_phases[StringDedupTableFixup]->set_enabled(G1StringDedup::is_enabled());

}

void G1GCPhaseTimes::note_gc_end() {

  for (uint i = 0; i < _active_gc_threads; i++) {

    double worker_time = _gc_par_phases[GCWorkerEnd]->get(i) - _gc_par_phases[GCWorkerStart]->get(i);

    record_time_secs(GCWorkerTotal, i , worker_time);

    double worker_known_time =

        _gc_par_phases[ExtRootScan]->get(i) +

        _gc_par_phases[SATBFiltering]->get(i) +

        _gc_par_phases[UpdateRS]->get(i) +

        _gc_par_phases[ScanRS]->get(i) +

        _gc_par_phases[CodeRoots]->get(i) +

        _gc_par_phases[ObjCopy]->get(i) +

        _gc_par_phases[Termination]->get(i);

    record_time_secs(Other, i, worker_time - worker_known_time);

  }

  for (int i = 0; i < GCParPhasesSentinel; i++) {

    _gc_par_phases[i]->verify(_active_gc_threads);

  }

}

void G1GCPhaseTimes::print_stats(int level, const char* str, double value) {

  LineBuffer(level).append_and_print_cr("[%s: %.1lf ms]", str, value);

}

void G1GCPhaseTimes::print_stats(int level, const char* str, size_t value) {

  LineBuffer(level).append_and_print_cr("[%s: " SIZE_FORMAT "]", str, value);

}

void G1GCPhaseTimes::print_stats(int level, const char* str, double value, uint workers) {

  LineBuffer(level).append_and_print_cr("[%s: %.1lf ms, GC Workers: %u]", str, value, workers);

}

double G1GCPhaseTimes::accounted_time_ms() {

    // Subtract the root region scanning wait time. It's initialized to

    // zero at the start of the pause.

    double misc_time_ms = _root_region_scan_wait_time_ms;

    misc_time_ms += _cur_collection_par_time_ms;

    // Now subtract the time taken to fix up roots in generated code

    misc_time_ms += _cur_collection_code_root_fixup_time_ms;

    // Strong code root purge time

    misc_time_ms += _cur_strong_code_root_purge_time_ms;

    if (G1StringDedup::is_enabled()) {

      // String dedup fixup time

      misc_time_ms += _cur_string_dedup_fixup_time_ms;

    }

    // Subtract the time taken to clean the card table from the

    // current value of "other time"

    misc_time_ms += _cur_clear_ct_time_ms;

    return misc_time_ms;

}

// record the time a phase took in seconds

void G1GCPhaseTimes::record_time_secs(GCParPhases phase, uint worker_i, double secs) {

  _gc_par_phases[phase]->set(worker_i, secs);

}

// add a number of seconds to a phase

void G1GCPhaseTimes::add_time_secs(GCParPhases phase, uint worker_i, double secs) {

  _gc_par_phases[phase]->add(worker_i, secs);

}

void G1GCPhaseTimes::record_thread_work_item(GCParPhases phase, uint worker_i, size_t count) {

  _gc_par_phases[phase]->set_thread_work_item(worker_i, count);

}

// return the average time for a phase in milliseconds

double G1GCPhaseTimes::average_time_ms(GCParPhases phase) {

  return _gc_par_phases[phase]->average(_active_gc_threads) * 1000.0;

}

double G1GCPhaseTimes::get_time_ms(GCParPhases phase, uint worker_i) {

  return _gc_par_phases[phase]->get(worker_i) * 1000.0;

}

double G1GCPhaseTimes::sum_time_ms(GCParPhases phase) {

  return _gc_par_phases[phase]->sum(_active_gc_threads) * 1000.0;

}

double G1GCPhaseTimes::min_time_ms(GCParPhases phase) {

  return _gc_par_phases[phase]->minimum(_active_gc_threads) * 1000.0;

}

double G1GCPhaseTimes::max_time_ms(GCParPhases phase) {

  return _gc_par_phases[phase]->maximum(_active_gc_threads) * 1000.0;

}

size_t G1GCPhaseTimes::get_thread_work_item(GCParPhases phase, uint worker_i) {

  assert(_gc_par_phases[phase]->thread_work_items() != NULL, "No sub count");

  return _gc_par_phases[phase]->thread_work_items()->get(worker_i);

}

size_t G1GCPhaseTimes::sum_thread_work_items(GCParPhases phase) {

  assert(_gc_par_phases[phase]->thread_work_items() != NULL, "No sub count");

  return _gc_par_phases[phase]->thread_work_items()->sum(_active_gc_threads);

}

double G1GCPhaseTimes::average_thread_work_items(GCParPhases phase) {

  assert(_gc_par_phases[phase]->thread_work_items() != NULL, "No sub count");

  return _gc_par_phases[phase]->thread_work_items()->average(_active_gc_threads);

}

size_t G1GCPhaseTimes::min_thread_work_items(GCParPhases phase) {

  assert(_gc_par_phases[phase]->thread_work_items() != NULL, "No sub count");

  return _gc_par_phases[phase]->thread_work_items()->minimum(_active_gc_threads);

}

size_t G1GCPhaseTimes::max_thread_work_items(GCParPhases phase) {

  assert(_gc_par_phases[phase]->thread_work_items() != NULL, "No sub count");

  return _gc_par_phases[phase]->thread_work_items()->maximum(_active_gc_threads);

}

class G1GCParPhasePrinter : public StackObj {

  G1GCPhaseTimes* _phase_times;

 public:

  G1GCParPhasePrinter(G1GCPhaseTimes* phase_times) : _phase_times(phase_times) {}

  void print(G1GCPhaseTimes::GCParPhases phase_id) {

    WorkerDataArray<double>* phase = _phase_times->_gc_par_phases[phase_id];

    if (phase->_log_level > G1Log::level() || !phase->_enabled) {

      return;

    }

    if (phase->_length == 1) {

      print_single_length(phase_id, phase);

    } else {

      print_multi_length(phase_id, phase);

    }

  }

 private:

  void print_single_length(G1GCPhaseTimes::GCParPhases phase_id, WorkerDataArray<double>* phase) {

    // No need for min, max, average and sum for only one worker

    LineBuffer buf(phase->_indent_level);

    buf.append_and_print_cr("[%s:  %.1lf]", phase->_title, _phase_times->get_time_ms(phase_id, 0));

    if (phase->_thread_work_items != NULL) {

      LineBuffer buf2(phase->_thread_work_items->_indent_level);

      buf2.append_and_print_cr("[%s:  " SIZE_FORMAT "]", phase->_thread_work_items->_title, _phase_times->sum_thread_work_items(phase_id));

    }

  }

  void print_time_values(LineBuffer& buf, G1GCPhaseTimes::GCParPhases phase_id, WorkerDataArray<double>* phase) {

    uint active_length = _phase_times->_active_gc_threads;

    for (uint i = 0; i < active_length; ++i) {

      buf.append("  %.1lf", _phase_times->get_time_ms(phase_id, i));

    }

    buf.print_cr();

  }

  void print_count_values(LineBuffer& buf, G1GCPhaseTimes::GCParPhases phase_id, WorkerDataArray<size_t>* thread_work_items) {

    uint active_length = _phase_times->_active_gc_threads;

    for (uint i = 0; i < active_length; ++i) {

      buf.append("  " SIZE_FORMAT, _phase_times->get_thread_work_item(phase_id, i));

    }

    buf.print_cr();

  }

  void print_thread_work_items(G1GCPhaseTimes::GCParPhases phase_id, WorkerDataArray<size_t>* thread_work_items) {

    LineBuffer buf(thread_work_items->_indent_level);

    buf.append("[%s:", thread_work_items->_title);

    if (G1Log::finest()) {

      print_count_values(buf, phase_id, thread_work_items);

    }

    buf.append_and_print_cr(" Min: " SIZE_FORMAT ", Avg: %.1lf, Max: " SIZE_FORMAT ", Diff: " SIZE_FORMAT ", Sum: " SIZE_FORMAT "]",

        _phase_times->min_thread_work_items(phase_id), _phase_times->average_thread_work_items(phase_id), _phase_times->max_thread_work_items(phase_id),

        _phase_times->max_thread_work_items(phase_id) - _phase_times->min_thread_work_items(phase_id), _phase_times->sum_thread_work_items(phase_id));

  }

  void print_multi_length(G1GCPhaseTimes::GCParPhases phase_id, WorkerDataArray<double>* phase) {

    LineBuffer buf(phase->_indent_level);

    buf.append("[%s:", phase->_title);

    if (G1Log::finest()) {

      print_time_values(buf, phase_id, phase);