/*

 * Copyright (c) 2013, 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_implementation/g1/g1CollectedHeap.inline.hpp"

#include "gc_implementation/g1/g1GCPhaseTimes.hpp"

#include "gc_implementation/g1/g1Log.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) {

    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, ...) {

    va_list ap;

    va_start(ap, format);

    vappend(format, ap);

    va_end(ap);

  }

  void append_and_print_cr(const char* format, ...) {

    va_list ap;

    va_start(ap, format);

    vappend(format, ap);

    va_end(ap);

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

    _cur = _indent_level * INDENT_CHARS;

  }

};

template <class T>

void WorkerDataArray<T>::print(int level, const char* title) {

  if (_length == 1) {

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

    LineBuffer buf(level);

    buf.append("[%s:  ", title);

    buf.append(_print_format, _data[0]);

    buf.append_and_print_cr("]");

    return;

  }

  T min = _data[0];

  T max = _data[0];

  T sum = 0;

  LineBuffer buf(level);

  buf.append("[%s:", title);

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

    T val = _data[i];

    min = MIN2(val, min);

    max = MAX2(val, max);

    sum += val;

    if (G1Log::finest()) {

      buf.append("  ");

      buf.append(_print_format, val);

    }

  }

  if (G1Log::finest()) {

    buf.append_and_print_cr("");

  }

  double avg = (double)sum / (double)_length;

  buf.append(" Min: ");

  buf.append(_print_format, min);

  buf.append(", Avg: ");

  buf.append("%.1lf", avg); // Always print average as a double

  buf.append(", Max: ");

  buf.append(_print_format, max);

  buf.append(", Diff: ");

  buf.append(_print_format, max - min);

  if (_print_sum) {

    // for things like the start and end times the sum is not

    // that relevant

    buf.append(", Sum: ");

    buf.append(_print_format, sum);

  }

  buf.append_and_print_cr("]");

}

#ifndef PRODUCT

template <> const int WorkerDataArray<int>::_uninitialized = -1;

template <> const double WorkerDataArray<double>::_uninitialized = -1.0;

template <> const size_t WorkerDataArray<size_t>::_uninitialized = (size_t)-1;

template <class T>

void WorkerDataArray<T>::reset() {

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

    _data[i] = (T)_uninitialized;

  }

}

template <class T>

void WorkerDataArray<T>::verify() {

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

    assert(_data[i] != _uninitialized,

        err_msg("Invalid data for worker " UINT32_FORMAT ", data: %lf, uninitialized: %lf",

            i, (double)_data[i], (double)_uninitialized));

  }

}

#endif

G1GCPhaseTimes::G1GCPhaseTimes(uint max_gc_threads) :

  _max_gc_threads(max_gc_threads),

  _last_gc_worker_start_times_ms(_max_gc_threads, "%.1lf", false),

  _last_ext_root_scan_times_ms(_max_gc_threads, "%.1lf"),

  _last_satb_filtering_times_ms(_max_gc_threads, "%.1lf"),

  _last_update_rs_times_ms(_max_gc_threads, "%.1lf"),

  _last_update_rs_processed_buffers(_max_gc_threads, "%d"),

  _last_scan_rs_times_ms(_max_gc_threads, "%.1lf"),

  _last_obj_copy_times_ms(_max_gc_threads, "%.1lf"),

  _last_termination_times_ms(_max_gc_threads, "%.1lf"),

  _last_termination_attempts(_max_gc_threads, SIZE_FORMAT),

  _last_gc_worker_end_times_ms(_max_gc_threads, "%.1lf", false),

  _last_gc_worker_times_ms(_max_gc_threads, "%.1lf"),

  _last_gc_worker_other_times_ms(_max_gc_threads, "%.1lf")

{

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

}

void G1GCPhaseTimes::note_gc_start(uint active_gc_threads) {

  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 nubmer of threads");

  _active_gc_threads = active_gc_threads;

  _last_gc_worker_start_times_ms.reset();

  _last_ext_root_scan_times_ms.reset();

  _last_satb_filtering_times_ms.reset();

  _last_update_rs_times_ms.reset();

  _last_update_rs_processed_buffers.reset();

  _last_scan_rs_times_ms.reset();

  _last_obj_copy_times_ms.reset();

  _last_termination_times_ms.reset();

  _last_termination_attempts.reset();

  _last_gc_worker_end_times_ms.reset();

  _last_gc_worker_times_ms.reset();

  _last_gc_worker_other_times_ms.reset();

}

void G1GCPhaseTimes::note_gc_end() {

  _last_gc_worker_start_times_ms.verify();

  _last_ext_root_scan_times_ms.verify();

  _last_satb_filtering_times_ms.verify();

  _last_update_rs_times_ms.verify();

  _last_update_rs_processed_buffers.verify();

  _last_scan_rs_times_ms.verify();

  _last_obj_copy_times_ms.verify();

  _last_termination_times_ms.verify();

  _last_termination_attempts.verify();

  _last_gc_worker_end_times_ms.verify();

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

    double worker_time = _last_gc_worker_end_times_ms.get(i) - _last_gc_worker_start_times_ms.get(i);

    _last_gc_worker_times_ms.set(i, worker_time);

    double worker_known_time = _last_ext_root_scan_times_ms.get(i) +

                               _last_satb_filtering_times_ms.get(i) +

                               _last_update_rs_times_ms.get(i) +

                               _last_scan_rs_times_ms.get(i) +

                               _last_obj_copy_times_ms.get(i) +

                               _last_termination_times_ms.get(i);

    double worker_other_time = worker_time - worker_known_time;

    _last_gc_worker_other_times_ms.set(i, worker_other_time);

  }

  _last_gc_worker_times_ms.verify();

  _last_gc_worker_other_times_ms.verify();

}

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, double value, int workers) {

  LineBuffer(level).append_and_print_cr("[%s: %.1lf ms, GC Workers: %d]", 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;

    // 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;

}

void G1GCPhaseTimes::print(double pause_time_sec) {

  if (_root_region_scan_wait_time_ms > 0.0) {

    print_stats(1, "Root Region Scan Waiting", _root_region_scan_wait_time_ms);

  }

  if (G1CollectedHeap::use_parallel_gc_threads()) {

    print_stats(1, "Parallel Time", _cur_collection_par_time_ms, _active_gc_threads);

    _last_gc_worker_start_times_ms.print(2, "GC Worker Start (ms)");

    _last_ext_root_scan_times_ms.print(2, "Ext Root Scanning (ms)");

    if (_last_satb_filtering_times_ms.sum() > 0.0) {

      _last_satb_filtering_times_ms.print(2, "SATB Filtering (ms)");

    }

    _last_update_rs_times_ms.print(2, "Update RS (ms)");

      _last_update_rs_processed_buffers.print(3, "Processed Buffers");

    _last_scan_rs_times_ms.print(2, "Scan RS (ms)");

    _last_obj_copy_times_ms.print(2, "Object Copy (ms)");

    _last_termination_times_ms.print(2, "Termination (ms)");

    if (G1Log::finest()) {

      _last_termination_attempts.print(3, "Termination Attempts");

    }

    _last_gc_worker_other_times_ms.print(2, "GC Worker Other (ms)");

    _last_gc_worker_times_ms.print(2, "GC Worker Total (ms)");

    _last_gc_worker_end_times_ms.print(2, "GC Worker End (ms)");

  } else {

    _last_ext_root_scan_times_ms.print(1, "Ext Root Scanning (ms)");

    if (_last_satb_filtering_times_ms.sum() > 0.0) {

      _last_satb_filtering_times_ms.print(1, "SATB Filtering (ms)");

    }

    _last_update_rs_times_ms.print(1, "Update RS (ms)");

      _last_update_rs_processed_buffers.print(2, "Processed Buffers");

    _last_scan_rs_times_ms.print(1, "Scan RS (ms)");

    _last_obj_copy_times_ms.print(1, "Object Copy (ms)");

  }

  print_stats(1, "Code Root Fixup", _cur_collection_code_root_fixup_time_ms);

  print_stats(1, "Clear CT", _cur_clear_ct_time_ms);

  double misc_time_ms = pause_time_sec * MILLIUNITS - accounted_time_ms();

  print_stats(1, "Other", misc_time_ms);

  if (_cur_verify_before_time_ms > 0.0) {

    print_stats(2, "Verify Before", _cur_verify_before_time_ms);

  }

  print_stats(2, "Choose CSet",

    (_recorded_young_cset_choice_time_ms +

    _recorded_non_young_cset_choice_time_ms));

  print_stats(2, "Ref Proc", _cur_ref_proc_time_ms);

  print_stats(2, "Ref Enq", _cur_ref_enq_time_ms);

  print_stats(2, "Free CSet",

    (_recorded_young_free_cset_time_ms +

    _recorded_non_young_free_cset_time_ms));

  if (_cur_verify_after_time_ms > 0.0) {

    print_stats(2, "Verify After", _cur_verify_after_time_ms);

  }

}