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 <cstddef>
8 #include <cstdlib>
9 #include <iostream>
10 #include <stdexcept>
11
12 #include <windows.h>
13
14 #include <boost/chrono.hpp>
15 #include <boost/cstdint.hpp>
16 #include <boost/program_options.hpp>
17
18 #include "../bind_processor.hpp"
19 #include "../clock.hpp"
20 #include "../cycle.hpp"
21 #include "../../example/simple_stack_allocator.hpp"
22
23 typedef boost::context::simple_stack_allocator<
24 8 * 1024 * 1024, 64 * 1024, 8 * 1024
25 > stack_allocator;
26
27 boost::uint64_t jobs = 1000;
28 LPVOID fc, fm;
29
fn(LPVOID)30 VOID __stdcall fn( LPVOID)
31 { while ( true) ::SwitchToFiber( fm); }
32
measure_time()33 duration_type measure_time()
34 {
35 // cache warum-up
36 ::SwitchToFiber( fc);
37
38 time_point_type start( clock_type::now() );
39 for ( std::size_t i = 0; i < jobs; ++i) {
40 ::SwitchToFiber( fc);
41 }
42 duration_type total = clock_type::now() - start;
43 total -= overhead_clock(); // overhead of measurement
44 total /= jobs; // loops
45 total /= 2; // 2x jump_fcontext
46
47 return total;
48 }
49
50 #ifdef BOOST_CONTEXT_CYCLE
measure_cycles()51 cycle_type measure_cycles()
52 {
53 // cache warum-up
54 ::SwitchToFiber( fc);
55
56 cycle_type start( cycles() );
57 for ( std::size_t i = 0; i < jobs; ++i) {
58 ::SwitchToFiber( fc);
59 }
60 cycle_type total = cycles() - start;
61 total -= overhead_cycle(); // overhead of measurement
62 total /= jobs; // loops
63 total /= 2; // 2x jump_fcontext
64
65 return total;
66 }
67 #endif
68
main(int argc,char * argv[])69 int main( int argc, char * argv[])
70 {
71 try
72 {
73 bind_to_processor( 0);
74
75 boost::program_options::options_description desc("allowed options");
76 desc.add_options()
77 ("help", "help message")
78 ("jobs,j", boost::program_options::value< boost::uint64_t >( & jobs), "jobs to run");
79
80 boost::program_options::variables_map vm;
81 boost::program_options::store(
82 boost::program_options::parse_command_line(
83 argc,
84 argv,
85 desc),
86 vm);
87 boost::program_options::notify( vm);
88
89 if ( vm.count("help") ) {
90 std::cout << desc << std::endl;
91 return EXIT_SUCCESS;
92 }
93
94 fm = ::ConvertThreadToFiber( 0);
95 fc = ::CreateFiber( stack_allocator::default_stacksize(), fn, 0);
96
97 boost::uint64_t res = measure_time().count();
98 std::cout << "average of " << res << " nano seconds" << std::endl;
99 #ifdef BOOST_CONTEXT_CYCLE
100 res = measure_cycles();
101 std::cout << "average of " << res << " cpu cycles" << std::endl;
102 #endif
103
104 return EXIT_SUCCESS;
105 }
106 catch ( std::exception const& e)
107 { std::cerr << "exception: " << e.what() << std::endl; }
108 catch (...)
109 { std::cerr << "unhandled exception" << std::endl; }
110 return EXIT_FAILURE;
111 }
112