mutex.cpp

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/******************************************************************************
** Copyright © 2020 by J.M.McGuiness, coder@hussar.me.uk
**
** This library is free software; you can redistribute it and/or
** modify it under the terms of the GNU Lesser General Public
** License as published by the Free Software Foundation; either
** version 2.1 of the License, or (at your option) any later version.
**
** This library 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
** Lesser General Public License for more details.
**
** You should have received a copy of the GNU Lesser General Public
** License along with this library; if not, write to the Free Software
** Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
 
#include "stdafx.h"
 
#define BOOST_TEST_MODULE libjmmcg_tests
#include <boost/test/included/unit_test.hpp>
 
#include <boost/mpl/list.hpp>
#include <boost/thread/mutex.hpp>
 
#include "core/ave_deviation_meter.hpp"
#include "core/stats_output.hpp"
 
#include "core/jthread.hpp"
#include "core/thread_wrapper.hpp"
 
#include <chrono>
 
using namespace libjmmcg;
using namespace ppd;
 
using timed_results_t=ave_deviation_meter<double>;
 
template<class LkT>
struct details;
template<>
struct details<api_lock_traits<platform_api, heavyweight_threading>::anon_spin_event_type> {
   using mutex_t=api_lock_traits<platform_api, heavyweight_threading>::anon_spin_event_type;
   using lock_t=mutex_t::lock_type;
   using thread_t=jthread;
// TODO  using thread_t=thread<platform_api, heavyweight_threading>;
};
template<>
struct details<api_lock_traits<platform_api, heavyweight_threading>::mutex_type> {
   using mutex_t=api_lock_traits<platform_api, heavyweight_threading>::mutex_type;
   using lock_t=mutex_t::lock_type;
   using thread_t=jthread;
// TODO  using thread_t=thread<platform_api, heavyweight_threading>;
};
template<>
struct details<std::mutex> {
   using mutex_t=std::mutex;
   using lock_t=std::scoped_lock<mutex_t>;
   using thread_t=jthread;
};
template<>
struct details<boost::mutex> {
   using mutex_t=boost::mutex;
   using lock_t=boost::mutex::scoped_lock;
   using thread_t=jthread;
};
 
using lock_types=boost::mpl::list<
   details<api_lock_traits<platform_api, heavyweight_threading>::anon_spin_event_type>,
   details<api_lock_traits<platform_api, heavyweight_threading>::mutex_type>,
   details<std::mutex>,
   details<boost::mutex>
>;
 
BOOST_AUTO_TEST_SUITE(mutex_tests)
 
BOOST_AUTO_TEST_CASE(ctor) {
   using mutex_t=api_lock_traits<platform_api, heavyweight_threading>::anon_spin_event_type;
 
   mutex_t lk;
   BOOST_CHECK_NO_THROW(lk.lock());
   BOOST_CHECK_NO_THROW(lk.unlock());
}
 
BOOST_AUTO_TEST_CASE(scoped_lock) {
   using mutex_t=api_lock_traits<platform_api, heavyweight_threading>::anon_spin_event_type;
   using lock_t=mutex_t::lock_type;
 
   mutex_t lk;
   BOOST_CHECK_NO_THROW(const lock_t lker(lk));
}
 
BOOST_AUTO_TEST_CASE(multithreaded_scoped_lock) {
   using mutex_t=api_lock_traits<platform_api, heavyweight_threading>::anon_spin_event_type;
   using lock_t=mutex_t::lock_type;
   using thread_t=jthread;
 
   const std::size_t num_loops=1000;
   mutex_t lk;
   unsigned long i=0;
   {
      const thread_t thr1(
         [&lk, &i]() {
            for (std::size_t j=0; j<num_loops; ++j) {
               const lock_t lker(lk);
               ++i;
            }
         }
      );
      const thread_t thr2(
         [&lk, &i]() {
            for (std::size_t j=0; j<num_loops; ++j) {
               const lock_t lker(lk);
               ++i;
            }
         }
      );
      const thread_t thr3(
         [&lk, &i]() {
            for (std::size_t j=0; j<num_loops; ++j) {
               const lock_t lker(lk);
               ++i;
            }
         }
      );
      const thread_t thr4(
         [&lk, &i]() {
            for (std::size_t j=0; j<num_loops; ++j) {
               const lock_t lker(lk);
               ++i;
            }
         }
      );
   }
   BOOST_CHECK_EQUAL(i, 4*num_loops);
}
 
BOOST_AUTO_TEST_SUITE(performance, *stats_to_csv::make_fixture("mutex.csv"))
 
/**
   \test <a href="./examples/mutex.svg">Graph</a> of performance results for a spin-lock based mutex versus other common mutexes.
         ==========================================================================================
   Results for 100*10000 repetitions.
*/
BOOST_AUTO_TEST_CASE_TEMPLATE(multithreaded_scoped_lock, details_t, lock_types) {
#ifdef JMMCG_PERFORMANCE_TESTS
   const std::size_t num_tests=5000;
   const std::size_t num_loops=500000;
#else
   const std::size_t num_tests=1;
   const std::size_t num_loops=1000;
#endif
 
   const std::pair<timed_results_t, bool> timed_results(compute_average_deviation<timed_results_t::value_type>(
      2.0,
      num_tests,
      []() {
         using mutex_t=typename details_t::mutex_t;
         using lock_t=typename details_t::lock_t;
         using thread_t=typename details_t::thread_t;
 
         mutex_t lk;
         unsigned long i=0;
         const std::chrono::high_resolution_clock::time_point t1=std::chrono::high_resolution_clock::now();
         {
            const thread_t thr1(
               [&lk, &i]() {
                  for (std::size_t j=0; j<num_loops; ++j) {
                     const lock_t lker(lk);
                     ++i;
                  }
               }
            );
            const thread_t thr2(
               [&lk, &i]() {
                  for (std::size_t j=0; j<num_loops; ++j) {
                     const lock_t lker(lk);
                     ++i;
                  }
               }
            );
            const thread_t thr3(
               [&lk, &i]() {
                  for (std::size_t j=0; j<num_loops; ++j) {
                     const lock_t lker(lk);
                     ++i;
                  }
               }
            );
            const thread_t thr4(
               [&lk, &i]() {
                  for (std::size_t j=0; j<num_loops; ++j) {
                     const lock_t lker(lk);
                     ++i;
                  }
               }
            );
         }
         const std::chrono::high_resolution_clock::time_point t2=std::chrono::high_resolution_clock::now();
         BOOST_CHECK_EQUAL(i, 4*num_loops);
         return timed_results_t::value_type(static_cast<double>(std::chrono::duration_cast<std::chrono::microseconds>(t2 - t1).count())/(4*num_loops));
      }
   ));
   std::cout<<api_threading_traits<platform_api, heavyweight_threading>::demangle_name(typeid(typename details_t::mutex_t))<<" locks-unlock in usec="<<timed_results.first<<std::endl;
#ifdef JMMCG_PERFORMANCE_TESTS
   stats_to_csv::handle->stats<<timed_results.first.to_csv()<<std::flush;
   BOOST_CHECK(!timed_results.second);
#endif
}
 
BOOST_AUTO_TEST_SUITE_END()
 
BOOST_AUTO_TEST_SUITE_END()