text: // Copyright (c) 2018 Jyocoin Project, Derived from 2016-2018, The Monero Project
  // 
  // All rights reserved.
  // 
  // Redistribution and use in source and binary forms, with or without modification, are
  // permitted provided that the following conditions are met:
  // 
  // 1. Redistributions of source code must retain the above copyright notice, this list of
  //    conditions and the following disclaimer.
  // 
  // 2. Redistributions in binary form must reproduce the above copyright notice, this list
  //    of conditions and the following disclaimer in the documentation and/or other
  //    materials provided with the distribution.
  // 
  // 3. Neither the name of the copyright holder nor the names of its contributors may be
  //    used to endorse or promote products derived from this software without specific
  //    prior written permission.
  // 
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
  // EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  // MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
  // THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  // PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
  // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  #include <vector>
  #include "misc_os_dependent.h"
  #include "perf_timer.h"
  
  #undef jyocoin_DEFAULT_LOG_CATEGORY
  #define jyocoin_DEFAULT_LOG_CATEGORY "perf"
  
  namespace tools
  {
    uint64_t get_tick_count()
    {
  #if defined(__x86_64__)
      uint32_t hi, lo;
      __asm__ volatile("rdtsc" : "=a"(lo), "=d"(hi));
      return (((uint64_t)hi) << 32) | (uint64_t)lo;
  #else
      return epee::misc_utils::get_ns_count();
  #endif
    }
  
  #ifdef __x86_64__
    uint64_t get_ticks_per_ns()
    {
      uint64_t t0 = epee::misc_utils::get_ns_count(), t1;
      uint64_t r0 = get_tick_count();
  
      while (1)
      {
        t1 = epee::misc_utils::get_ns_count();
        if (t1 - t0 > 1*1000000000) break; // work one second
      }
  
      uint64_t r1 = get_tick_count();
      uint64_t tpns256 = 256 * (r1 - r0) / (t1 - t0);
      return tpns256 ? tpns256 : 1;
    }
  #endif
  
  #ifdef __x86_64__
    uint64_t ticks_per_ns = get_ticks_per_ns();
  #endif
  
    uint64_t ticks_to_ns(uint64_t ticks)
    {
  #if defined(__x86_64__)
      return 256 * ticks / ticks_per_ns;
  #else
      return ticks;
  #endif
    }
  }
  
  namespace tools
  {
  
  el::Level performance_timer_log_level = el::Level::Debug;
  
  static __thread std::vector<LoggingPerformanceTimer*> *performance_timers = NULL;
  
  void set_performance_timer_log_level(el::Level level)
  {
    if (level != el::Level::Debug && level != el::Level::Trace && level != el::Level::Info
     && level != el::Level::Warning && level != el::Level::Error && level != el::Level::Fatal)
    {
      MERROR("Wrong log level: " << el::LevelHelper::convertToString(level) << ", using Debug");
      level = el::Level::Debug;
    }
    performance_timer_log_level = level;
  }
  
  PerformanceTimer::PerformanceTimer(bool paused): started(true), paused(paused)
  {
    if (paused)
      ticks = 0;
    else
      ticks = get_tick_count();
  }
  
  LoggingPerformanceTimer::LoggingPerformanceTimer(const std::string &s, const std::string &cat, uint64_t unit, el::Level l): PerformanceTimer(), name(s), cat(cat), unit(unit), level(l)
  {
    if (!performance_timers)
    {
      MCLOG(level, cat.c_str(), "PERF             ----------");
      performance_timers = new std::vector<LoggingPerformanceTimer*>();
      performance_timers->reserve(16); // how deep before realloc
    }
    else
    {
      LoggingPerformanceTimer *pt = performance_timers->back();
      if (!pt->started && !pt->paused)
      {
        size_t size = 0; for (const auto *tmp: *performance_timers) if (!tmp->paused) ++size;
        MCLOG(pt->level, cat.c_str(), "PERF           " << std::string((size-1) * 2, ' ') << "  " << pt->name);
        pt->started = true;
      }
    }
    performance_timers->push_back(this);
  }
  
  PerformanceTimer::~PerformanceTimer()
  {
    if (!paused)
      ticks = get_tick_count() - ticks;
  }
  
  LoggingPerformanceTimer::~LoggingPerformanceTimer()
  {
    pause();
    performance_timers->pop_back();
    char s[12];
    snprintf(s, sizeof(s), "%8llu  ", (unsigned long long)(ticks_to_ns(ticks) / (1000000000 / unit)));
    size_t size = 0; for (const auto *tmp: *performance_timers) if (!tmp->paused || tmp==this) ++size;
    MCLOG(level, cat.c_str(), "PERF " << s << std::string(size * 2, ' ') << "  " << name);
    if (performance_timers->empty())
    {
      delete performance_timers;
      performance_timers = NULL;
    }
  }
  
  void PerformanceTimer::pause()
  {
    if (paused)
      return;
    ticks = get_tick_count() - ticks;
    paused = true;
  }
  
  void PerformanceTimer::resume()
  {
    if (!paused)
      return;
    ticks = get_tick_count() - ticks;
    paused = false;
  }
  
  }
  