// Copyright Oliver Kowalke 2014. // Distributed under the Boost Software License, Version 1.0. // (See accompanying file LICENSE_1_0.txt or copy at // http://www.boost.org/LICENSE_1_0.txt) #include <cstdlib> #include <iostream> #include <stdexcept> #include <boost/chrono.hpp> #include <boost/coroutine2/all.hpp> #include <boost/cstdint.hpp> #include <boost/program_options.hpp> #include "bind_processor.hpp" #include "clock.hpp" #include "cycle.hpp" typedef boost::coroutines2::fixedsize_stack stack_allocator; typedef boost::coroutines2::coroutine< void > coro_type; bool preserve = false; boost::uint64_t jobs = 1000; void fn( coro_type::pull_type & c) { while ( true) c(); } duration_type measure_time( duration_type overhead) { stack_allocator stack_alloc; time_point_type start( clock_type::now() ); for ( std::size_t i = 0; i < jobs; ++i) { coro_type::push_type c( stack_alloc, fn, preserve); } duration_type total = clock_type::now() - start; total -= overhead_clock(); // overhead of measurement total /= jobs; // loops return total; } # ifdef BOOST_CONTEXT_CYCLE cycle_type measure_cycles( cycle_type overhead) { stack_allocator stack_alloc; cycle_type start( cycles() ); for ( std::size_t i = 0; i < jobs; ++i) { coro_type::push_type c( stack_alloc, fn, preserve); } cycle_type total = cycles() - start; total -= overhead; // overhead of measurement total /= jobs; // loops return total; } # endif int main( int argc, char * argv[]) { try { bool bind = false; boost::program_options::options_description desc("allowed options"); desc.add_options() ("help", "help message") ("bind,b", boost::program_options::value< bool >( & bind), "bind thread to CPU") ("fpu,f", boost::program_options::value< bool >( & preserve), "preserve FPU registers") ("jobs,j", boost::program_options::value< boost::uint64_t >( & jobs), "jobs to run"); boost::program_options::variables_map vm; boost::program_options::store( boost::program_options::parse_command_line( argc, argv, desc), vm); boost::program_options::notify( vm); if ( vm.count("help") ) { std::cout << desc << std::endl; return EXIT_SUCCESS; } if ( bind) bind_to_processor( 0); duration_type overhead_c = overhead_clock(); std::cout << "overhead " << overhead_c.count() << " nano seconds" << std::endl; boost::uint64_t res = measure_time( overhead_c).count(); std::cout << "average of " << res << " nano seconds" << std::endl; #ifdef BOOST_CONTEXT_CYCLE cycle_type overhead_y = overhead_cycle(); std::cout << "overhead " << overhead_y << " cpu cycles" << std::endl; res = measure_cycles( overhead_y); std::cout << "average of " << res << " cpu cycles" << std::endl; #endif return EXIT_SUCCESS; } catch ( std::exception const& e) { std::cerr << "exception: " << e.what() << std::endl; } catch (...) { std::cerr << "unhandled exception" << std::endl; } return EXIT_FAILURE; }