Jakub Kotur | 5dd645c | 2020-12-21 17:28:14 +0100 | [diff] [blame] | 1 | use std::sync::atomic::Ordering::SeqCst; |
| 2 | use std::sync::atomic::{AtomicBool, AtomicUsize}; |
| 3 | use std::sync::{Arc, Mutex}; |
| 4 | |
| 5 | use crossbeam_deque::Steal::{Empty, Success}; |
| 6 | use crossbeam_deque::Worker; |
| 7 | use crossbeam_utils::thread::scope; |
| 8 | use rand::Rng; |
| 9 | |
| 10 | #[test] |
| 11 | fn smoke() { |
| 12 | let w = Worker::new_lifo(); |
| 13 | let s = w.stealer(); |
| 14 | assert_eq!(w.pop(), None); |
| 15 | assert_eq!(s.steal(), Empty); |
| 16 | |
| 17 | w.push(1); |
| 18 | assert_eq!(w.pop(), Some(1)); |
| 19 | assert_eq!(w.pop(), None); |
| 20 | assert_eq!(s.steal(), Empty); |
| 21 | |
| 22 | w.push(2); |
| 23 | assert_eq!(s.steal(), Success(2)); |
| 24 | assert_eq!(s.steal(), Empty); |
| 25 | assert_eq!(w.pop(), None); |
| 26 | |
| 27 | w.push(3); |
| 28 | w.push(4); |
| 29 | w.push(5); |
| 30 | assert_eq!(s.steal(), Success(3)); |
| 31 | assert_eq!(s.steal(), Success(4)); |
| 32 | assert_eq!(s.steal(), Success(5)); |
| 33 | assert_eq!(s.steal(), Empty); |
| 34 | |
| 35 | w.push(6); |
| 36 | w.push(7); |
| 37 | w.push(8); |
| 38 | w.push(9); |
| 39 | assert_eq!(w.pop(), Some(9)); |
| 40 | assert_eq!(s.steal(), Success(6)); |
| 41 | assert_eq!(w.pop(), Some(8)); |
| 42 | assert_eq!(w.pop(), Some(7)); |
| 43 | assert_eq!(w.pop(), None); |
| 44 | } |
| 45 | |
| 46 | #[test] |
| 47 | fn is_empty() { |
| 48 | let w = Worker::new_lifo(); |
| 49 | let s = w.stealer(); |
| 50 | |
| 51 | assert!(w.is_empty()); |
| 52 | w.push(1); |
| 53 | assert!(!w.is_empty()); |
| 54 | w.push(2); |
| 55 | assert!(!w.is_empty()); |
| 56 | let _ = w.pop(); |
| 57 | assert!(!w.is_empty()); |
| 58 | let _ = w.pop(); |
| 59 | assert!(w.is_empty()); |
| 60 | |
| 61 | assert!(s.is_empty()); |
| 62 | w.push(1); |
| 63 | assert!(!s.is_empty()); |
| 64 | w.push(2); |
| 65 | assert!(!s.is_empty()); |
| 66 | let _ = s.steal(); |
| 67 | assert!(!s.is_empty()); |
| 68 | let _ = s.steal(); |
| 69 | assert!(s.is_empty()); |
| 70 | } |
| 71 | |
| 72 | #[test] |
| 73 | fn spsc() { |
| 74 | const STEPS: usize = 50_000; |
| 75 | |
| 76 | let w = Worker::new_lifo(); |
| 77 | let s = w.stealer(); |
| 78 | |
| 79 | scope(|scope| { |
| 80 | scope.spawn(|_| { |
| 81 | for i in 0..STEPS { |
| 82 | loop { |
| 83 | if let Success(v) = s.steal() { |
| 84 | assert_eq!(i, v); |
| 85 | break; |
| 86 | } |
| 87 | } |
| 88 | } |
| 89 | |
| 90 | assert_eq!(s.steal(), Empty); |
| 91 | }); |
| 92 | |
| 93 | for i in 0..STEPS { |
| 94 | w.push(i); |
| 95 | } |
| 96 | }) |
| 97 | .unwrap(); |
| 98 | } |
| 99 | |
| 100 | #[test] |
| 101 | fn stampede() { |
| 102 | const THREADS: usize = 8; |
| 103 | const COUNT: usize = 50_000; |
| 104 | |
| 105 | let w = Worker::new_lifo(); |
| 106 | |
| 107 | for i in 0..COUNT { |
| 108 | w.push(Box::new(i + 1)); |
| 109 | } |
| 110 | let remaining = Arc::new(AtomicUsize::new(COUNT)); |
| 111 | |
| 112 | scope(|scope| { |
| 113 | for _ in 0..THREADS { |
| 114 | let s = w.stealer(); |
| 115 | let remaining = remaining.clone(); |
| 116 | |
| 117 | scope.spawn(move |_| { |
| 118 | let mut last = 0; |
| 119 | while remaining.load(SeqCst) > 0 { |
| 120 | if let Success(x) = s.steal() { |
| 121 | assert!(last < *x); |
| 122 | last = *x; |
| 123 | remaining.fetch_sub(1, SeqCst); |
| 124 | } |
| 125 | } |
| 126 | }); |
| 127 | } |
| 128 | |
| 129 | let mut last = COUNT + 1; |
| 130 | while remaining.load(SeqCst) > 0 { |
| 131 | if let Some(x) = w.pop() { |
| 132 | assert!(last > *x); |
| 133 | last = *x; |
| 134 | remaining.fetch_sub(1, SeqCst); |
| 135 | } |
| 136 | } |
| 137 | }) |
| 138 | .unwrap(); |
| 139 | } |
| 140 | |
| 141 | #[test] |
| 142 | fn stress() { |
| 143 | const THREADS: usize = 8; |
| 144 | const COUNT: usize = 50_000; |
| 145 | |
| 146 | let w = Worker::new_lifo(); |
| 147 | let done = Arc::new(AtomicBool::new(false)); |
| 148 | let hits = Arc::new(AtomicUsize::new(0)); |
| 149 | |
| 150 | scope(|scope| { |
| 151 | for _ in 0..THREADS { |
| 152 | let s = w.stealer(); |
| 153 | let done = done.clone(); |
| 154 | let hits = hits.clone(); |
| 155 | |
| 156 | scope.spawn(move |_| { |
| 157 | let w2 = Worker::new_lifo(); |
| 158 | |
| 159 | while !done.load(SeqCst) { |
| 160 | if let Success(_) = s.steal() { |
| 161 | hits.fetch_add(1, SeqCst); |
| 162 | } |
| 163 | |
| 164 | let _ = s.steal_batch(&w2); |
| 165 | |
| 166 | if let Success(_) = s.steal_batch_and_pop(&w2) { |
| 167 | hits.fetch_add(1, SeqCst); |
| 168 | } |
| 169 | |
Joel Galenson | f0b1773 | 2021-08-09 10:27:52 -0700 | [diff] [blame] | 170 | while w2.pop().is_some() { |
Jakub Kotur | 5dd645c | 2020-12-21 17:28:14 +0100 | [diff] [blame] | 171 | hits.fetch_add(1, SeqCst); |
| 172 | } |
| 173 | } |
| 174 | }); |
| 175 | } |
| 176 | |
| 177 | let mut rng = rand::thread_rng(); |
| 178 | let mut expected = 0; |
| 179 | while expected < COUNT { |
Joel Galenson | f0b1773 | 2021-08-09 10:27:52 -0700 | [diff] [blame] | 180 | if rng.gen_range(0..3) == 0 { |
| 181 | while w.pop().is_some() { |
Jakub Kotur | 5dd645c | 2020-12-21 17:28:14 +0100 | [diff] [blame] | 182 | hits.fetch_add(1, SeqCst); |
| 183 | } |
| 184 | } else { |
| 185 | w.push(expected); |
| 186 | expected += 1; |
| 187 | } |
| 188 | } |
| 189 | |
| 190 | while hits.load(SeqCst) < COUNT { |
Joel Galenson | f0b1773 | 2021-08-09 10:27:52 -0700 | [diff] [blame] | 191 | while w.pop().is_some() { |
Jakub Kotur | 5dd645c | 2020-12-21 17:28:14 +0100 | [diff] [blame] | 192 | hits.fetch_add(1, SeqCst); |
| 193 | } |
| 194 | } |
| 195 | done.store(true, SeqCst); |
| 196 | }) |
| 197 | .unwrap(); |
| 198 | } |
| 199 | |
| 200 | #[test] |
| 201 | fn no_starvation() { |
| 202 | const THREADS: usize = 8; |
| 203 | const COUNT: usize = 50_000; |
| 204 | |
| 205 | let w = Worker::new_lifo(); |
| 206 | let done = Arc::new(AtomicBool::new(false)); |
| 207 | let mut all_hits = Vec::new(); |
| 208 | |
| 209 | scope(|scope| { |
| 210 | for _ in 0..THREADS { |
| 211 | let s = w.stealer(); |
| 212 | let done = done.clone(); |
| 213 | let hits = Arc::new(AtomicUsize::new(0)); |
| 214 | all_hits.push(hits.clone()); |
| 215 | |
| 216 | scope.spawn(move |_| { |
| 217 | let w2 = Worker::new_lifo(); |
| 218 | |
| 219 | while !done.load(SeqCst) { |
| 220 | if let Success(_) = s.steal() { |
| 221 | hits.fetch_add(1, SeqCst); |
| 222 | } |
| 223 | |
| 224 | let _ = s.steal_batch(&w2); |
| 225 | |
| 226 | if let Success(_) = s.steal_batch_and_pop(&w2) { |
| 227 | hits.fetch_add(1, SeqCst); |
| 228 | } |
| 229 | |
Joel Galenson | f0b1773 | 2021-08-09 10:27:52 -0700 | [diff] [blame] | 230 | while w2.pop().is_some() { |
Jakub Kotur | 5dd645c | 2020-12-21 17:28:14 +0100 | [diff] [blame] | 231 | hits.fetch_add(1, SeqCst); |
| 232 | } |
| 233 | } |
| 234 | }); |
| 235 | } |
| 236 | |
| 237 | let mut rng = rand::thread_rng(); |
| 238 | let mut my_hits = 0; |
| 239 | loop { |
Joel Galenson | f0b1773 | 2021-08-09 10:27:52 -0700 | [diff] [blame] | 240 | for i in 0..rng.gen_range(0..COUNT) { |
| 241 | if rng.gen_range(0..3) == 0 && my_hits == 0 { |
| 242 | while w.pop().is_some() { |
Jakub Kotur | 5dd645c | 2020-12-21 17:28:14 +0100 | [diff] [blame] | 243 | my_hits += 1; |
| 244 | } |
| 245 | } else { |
| 246 | w.push(i); |
| 247 | } |
| 248 | } |
| 249 | |
| 250 | if my_hits > 0 && all_hits.iter().all(|h| h.load(SeqCst) > 0) { |
| 251 | break; |
| 252 | } |
| 253 | } |
| 254 | done.store(true, SeqCst); |
| 255 | }) |
| 256 | .unwrap(); |
| 257 | } |
| 258 | |
| 259 | #[test] |
| 260 | fn destructors() { |
| 261 | const THREADS: usize = 8; |
| 262 | const COUNT: usize = 50_000; |
| 263 | const STEPS: usize = 1000; |
| 264 | |
| 265 | struct Elem(usize, Arc<Mutex<Vec<usize>>>); |
| 266 | |
| 267 | impl Drop for Elem { |
| 268 | fn drop(&mut self) { |
| 269 | self.1.lock().unwrap().push(self.0); |
| 270 | } |
| 271 | } |
| 272 | |
| 273 | let w = Worker::new_lifo(); |
| 274 | let dropped = Arc::new(Mutex::new(Vec::new())); |
| 275 | let remaining = Arc::new(AtomicUsize::new(COUNT)); |
| 276 | |
| 277 | for i in 0..COUNT { |
| 278 | w.push(Elem(i, dropped.clone())); |
| 279 | } |
| 280 | |
| 281 | scope(|scope| { |
| 282 | for _ in 0..THREADS { |
| 283 | let remaining = remaining.clone(); |
| 284 | let s = w.stealer(); |
| 285 | |
| 286 | scope.spawn(move |_| { |
| 287 | let w2 = Worker::new_lifo(); |
| 288 | let mut cnt = 0; |
| 289 | |
| 290 | while cnt < STEPS { |
| 291 | if let Success(_) = s.steal() { |
| 292 | cnt += 1; |
| 293 | remaining.fetch_sub(1, SeqCst); |
| 294 | } |
| 295 | |
| 296 | let _ = s.steal_batch(&w2); |
| 297 | |
| 298 | if let Success(_) = s.steal_batch_and_pop(&w2) { |
| 299 | cnt += 1; |
| 300 | remaining.fetch_sub(1, SeqCst); |
| 301 | } |
| 302 | |
Joel Galenson | f0b1773 | 2021-08-09 10:27:52 -0700 | [diff] [blame] | 303 | while w2.pop().is_some() { |
Jakub Kotur | 5dd645c | 2020-12-21 17:28:14 +0100 | [diff] [blame] | 304 | cnt += 1; |
| 305 | remaining.fetch_sub(1, SeqCst); |
| 306 | } |
| 307 | } |
| 308 | }); |
| 309 | } |
| 310 | |
| 311 | for _ in 0..STEPS { |
Joel Galenson | f0b1773 | 2021-08-09 10:27:52 -0700 | [diff] [blame] | 312 | if w.pop().is_some() { |
Jakub Kotur | 5dd645c | 2020-12-21 17:28:14 +0100 | [diff] [blame] | 313 | remaining.fetch_sub(1, SeqCst); |
| 314 | } |
| 315 | } |
| 316 | }) |
| 317 | .unwrap(); |
| 318 | |
| 319 | let rem = remaining.load(SeqCst); |
| 320 | assert!(rem > 0); |
| 321 | |
| 322 | { |
| 323 | let mut v = dropped.lock().unwrap(); |
| 324 | assert_eq!(v.len(), COUNT - rem); |
| 325 | v.clear(); |
| 326 | } |
| 327 | |
| 328 | drop(w); |
| 329 | |
| 330 | { |
| 331 | let mut v = dropped.lock().unwrap(); |
| 332 | assert_eq!(v.len(), rem); |
| 333 | v.sort(); |
| 334 | for pair in v.windows(2) { |
| 335 | assert_eq!(pair[0] + 1, pair[1]); |
| 336 | } |
| 337 | } |
| 338 | } |