1
2 // Copyright Oliver Kowalke 2009.
3 // Distributed under the Boost Software License, Version 1.0.
4 // (See accompanying file LICENSE_1_0.txt or copy at
5 // http://www.boost.org/LICENSE_1_0.txt)
6
7 #include <cstdlib>
8 #include <iostream>
9 #include <stdexcept>
10
11 #include <boost/chrono.hpp>
12 #include <boost/coroutine/all.hpp>
13 #include <boost/cstdint.hpp>
14 #include <boost/program_options.hpp>
15
16 #include "../bind_processor.hpp"
17 #include "../clock.hpp"
18 #include "../cycle.hpp"
19
20 typedef boost::coroutines::standard_stack_allocator stack_allocator;
21 typedef boost::coroutines::symmetric_coroutine< void > coro_type;
22
23 boost::coroutines::flag_fpu_t preserve_fpu = boost::coroutines::fpu_not_preserved;
24 boost::coroutines::flag_unwind_t unwind_stack = boost::coroutines::stack_unwind;
25 boost::uint64_t jobs = 1000;
26
fn(coro_type::yield_type &)27 void fn( coro_type::yield_type &) {}
28
measure_time(duration_type overhead)29 duration_type measure_time( duration_type overhead)
30 {
31 stack_allocator stack_alloc;
32 boost::coroutines::attributes attrs( unwind_stack, preserve_fpu);
33
34 time_point_type start( clock_type::now() );
35 for ( std::size_t i = 0; i < jobs; ++i) {
36 coro_type::call_type c( fn, attrs, stack_alloc);
37 }
38 duration_type total = clock_type::now() - start;
39 total -= overhead; // overhead of measurement
40 total /= jobs; // loops
41
42 return total;
43 }
44
45 # ifdef BOOST_CONTEXT_CYCLE
measure_cycles(cycle_type overhead)46 cycle_type measure_cycles( cycle_type overhead)
47 {
48 stack_allocator stack_alloc;
49
50 cycle_type start( cycles() );
51 for ( std::size_t i = 0; i < jobs; ++i) {
52 coro_type::call_type c( fn,
53 boost::coroutines::attributes( unwind_stack, preserve_fpu), stack_alloc);
54 }
55 cycle_type total = cycles() - start;
56 total -= overhead; // overhead of measurement
57 total /= jobs; // loops
58
59 return total;
60 }
61 # endif
62
main(int argc,char * argv[])63 int main( int argc, char * argv[])
64 {
65 try
66 {
67 bool preserve = false, unwind = true, bind = false;
68 boost::program_options::options_description desc("allowed options");
69 desc.add_options()
70 ("help", "help message")
71 ("bind,b", boost::program_options::value< bool >( & bind), "bind thread to CPU")
72 ("fpu,f", boost::program_options::value< bool >( & preserve), "preserve FPU registers")
73 ("unwind,u", boost::program_options::value< bool >( & unwind), "unwind coroutine-stack")
74 ("jobs,j", boost::program_options::value< boost::uint64_t >( & jobs), "jobs to run");
75
76 boost::program_options::variables_map vm;
77 boost::program_options::store(
78 boost::program_options::parse_command_line(
79 argc,
80 argv,
81 desc),
82 vm);
83 boost::program_options::notify( vm);
84
85 if ( vm.count("help") ) {
86 std::cout << desc << std::endl;
87 return EXIT_SUCCESS;
88 }
89
90 if ( preserve) preserve_fpu = boost::coroutines::fpu_preserved;
91 if ( ! unwind) unwind_stack = boost::coroutines::no_stack_unwind;
92 if ( bind) bind_to_processor( 0);
93
94 duration_type overhead_c = overhead_clock();
95 std::cout << "overhead " << overhead_c.count() << " nano seconds" << std::endl;
96 boost::uint64_t res = measure_time( overhead_c).count();
97 std::cout << "average of " << res << " nano seconds" << std::endl;
98 #ifdef BOOST_CONTEXT_CYCLE
99 cycle_type overhead_y = overhead_cycle();
100 std::cout << "overhead " << overhead_y << " cpu cycles" << std::endl;
101 res = measure_cycles( overhead_y);
102 std::cout << "average of " << res << " cpu cycles" << std::endl;
103 #endif
104
105 return EXIT_SUCCESS;
106 }
107 catch ( std::exception const& e)
108 { std::cerr << "exception: " << e.what() << std::endl; }
109 catch (...)
110 { std::cerr << "unhandled exception" << std::endl; }
111 return EXIT_FAILURE;
112 }
113