| 1 | #![feature (test)] |
| 2 | |
| 3 | extern crate test; |
| 4 | |
| 5 | use std::sync::Barrier; |
| 6 | |
| 7 | use crossbeam_utils::atomic::AtomicCell; |
| 8 | use crossbeam_utils::thread; |
| 9 | |
| 10 | #[bench] |
| 11 | fn load_u8(b: &mut test::Bencher) { |
| 12 | let a = AtomicCell::new(0u8); |
| 13 | let mut sum = 0; |
| 14 | b.iter(|| sum += a.load()); |
| 15 | test::black_box(sum); |
| 16 | } |
| 17 | |
| 18 | #[bench] |
| 19 | fn store_u8(b: &mut test::Bencher) { |
| 20 | let a = AtomicCell::new(0u8); |
| 21 | b.iter(|| a.store(1)); |
| 22 | } |
| 23 | |
| 24 | #[bench] |
| 25 | fn fetch_add_u8(b: &mut test::Bencher) { |
| 26 | let a = AtomicCell::new(0u8); |
| 27 | b.iter(|| a.fetch_add(1)); |
| 28 | } |
| 29 | |
| 30 | #[bench] |
| 31 | fn compare_exchange_u8(b: &mut test::Bencher) { |
| 32 | let a = AtomicCell::new(0u8); |
| 33 | let mut i = 0; |
| 34 | b.iter(|| { |
| 35 | let _ = a.compare_exchange(i, i.wrapping_add(1)); |
| 36 | i = i.wrapping_add(1); |
| 37 | }); |
| 38 | } |
| 39 | |
| 40 | #[bench] |
| 41 | fn concurrent_load_u8(b: &mut test::Bencher) { |
| 42 | const THREADS: usize = 2; |
| 43 | const STEPS: usize = 1_000_000; |
| 44 | |
| 45 | let start = Barrier::new(THREADS + 1); |
| 46 | let end = Barrier::new(THREADS + 1); |
| 47 | let exit = AtomicCell::new(false); |
| 48 | |
| 49 | let a = AtomicCell::new(0u8); |
| 50 | |
| 51 | thread::scope(|scope| { |
| 52 | for _ in 0..THREADS { |
| 53 | scope.spawn(|_| loop { |
| 54 | start.wait(); |
| 55 | |
| 56 | let mut sum = 0; |
| 57 | for _ in 0..STEPS { |
| 58 | sum += a.load(); |
| 59 | } |
| 60 | test::black_box(sum); |
| 61 | |
| 62 | end.wait(); |
| 63 | if exit.load() { |
| 64 | break; |
| 65 | } |
| 66 | }); |
| 67 | } |
| 68 | |
| 69 | start.wait(); |
| 70 | end.wait(); |
| 71 | |
| 72 | b.iter(|| { |
| 73 | start.wait(); |
| 74 | end.wait(); |
| 75 | }); |
| 76 | |
| 77 | start.wait(); |
| 78 | exit.store(true); |
| 79 | end.wait(); |
| 80 | }) |
| 81 | .unwrap(); |
| 82 | } |
| 83 | |
| 84 | #[bench] |
| 85 | fn load_usize(b: &mut test::Bencher) { |
| 86 | let a = AtomicCell::new(0usize); |
| 87 | let mut sum = 0; |
| 88 | b.iter(|| sum += a.load()); |
| 89 | test::black_box(sum); |
| 90 | } |
| 91 | |
| 92 | #[bench] |
| 93 | fn store_usize(b: &mut test::Bencher) { |
| 94 | let a = AtomicCell::new(0usize); |
| 95 | b.iter(|| a.store(1)); |
| 96 | } |
| 97 | |
| 98 | #[bench] |
| 99 | fn fetch_add_usize(b: &mut test::Bencher) { |
| 100 | let a = AtomicCell::new(0usize); |
| 101 | b.iter(|| a.fetch_add(1)); |
| 102 | } |
| 103 | |
| 104 | #[bench] |
| 105 | fn compare_exchange_usize(b: &mut test::Bencher) { |
| 106 | let a = AtomicCell::new(0usize); |
| 107 | let mut i = 0; |
| 108 | b.iter(|| { |
| 109 | let _ = a.compare_exchange(i, i.wrapping_add(1)); |
| 110 | i = i.wrapping_add(1); |
| 111 | }); |
| 112 | } |
| 113 | |
| 114 | #[bench] |
| 115 | fn concurrent_load_usize(b: &mut test::Bencher) { |
| 116 | const THREADS: usize = 2; |
| 117 | const STEPS: usize = 1_000_000; |
| 118 | |
| 119 | let start = Barrier::new(THREADS + 1); |
| 120 | let end = Barrier::new(THREADS + 1); |
| 121 | let exit = AtomicCell::new(false); |
| 122 | |
| 123 | let a = AtomicCell::new(0usize); |
| 124 | |
| 125 | thread::scope(|scope| { |
| 126 | for _ in 0..THREADS { |
| 127 | scope.spawn(|_| loop { |
| 128 | start.wait(); |
| 129 | |
| 130 | let mut sum = 0; |
| 131 | for _ in 0..STEPS { |
| 132 | sum += a.load(); |
| 133 | } |
| 134 | test::black_box(sum); |
| 135 | |
| 136 | end.wait(); |
| 137 | if exit.load() { |
| 138 | break; |
| 139 | } |
| 140 | }); |
| 141 | } |
| 142 | |
| 143 | start.wait(); |
| 144 | end.wait(); |
| 145 | |
| 146 | b.iter(|| { |
| 147 | start.wait(); |
| 148 | end.wait(); |
| 149 | }); |
| 150 | |
| 151 | start.wait(); |
| 152 | exit.store(true); |
| 153 | end.wait(); |
| 154 | }) |
| 155 | .unwrap(); |
| 156 | } |
| 157 | |