67 lines
1.7 KiB
Rust
67 lines
1.7 KiB
Rust
use std::sync::atomic::AtomicUsize;
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use std::sync::atomic::Ordering::{AcqRel, Acquire, Relaxed};
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use std::sync::Arc;
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use std::thread;
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use std::time::{Duration, Instant};
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use crossbeam_epoch::{self as epoch, Atomic, Collector, LocalHandle, Owned, Shared};
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use rand::Rng;
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fn worker(a: Arc<Atomic<AtomicUsize>>, handle: LocalHandle) -> usize {
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let mut rng = rand::thread_rng();
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let mut sum = 0;
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if rng.gen() {
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thread::sleep(Duration::from_millis(1));
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}
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let timeout = Duration::from_millis(rng.gen_range(0..10));
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let now = Instant::now();
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while now.elapsed() < timeout {
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for _ in 0..100 {
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let guard = &handle.pin();
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guard.flush();
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let val = if rng.gen() {
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let p = a.swap(Owned::new(AtomicUsize::new(sum)), AcqRel, guard);
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unsafe {
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guard.defer_destroy(p);
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guard.flush();
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p.deref().load(Relaxed)
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}
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} else {
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let p = a.load(Acquire, guard);
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unsafe { p.deref().fetch_add(sum, Relaxed) }
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};
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sum = sum.wrapping_add(val);
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}
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}
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sum
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}
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fn main() {
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for _ in 0..100 {
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let collector = Collector::new();
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let a = Arc::new(Atomic::new(AtomicUsize::new(777)));
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let threads = (0..16)
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.map(|_| {
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let a = a.clone();
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let c = collector.clone();
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thread::spawn(move || worker(a, c.register()))
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})
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.collect::<Vec<_>>();
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for t in threads {
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t.join().unwrap();
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}
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unsafe {
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a.swap(Shared::null(), AcqRel, epoch::unprotected())
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.into_owned();
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}
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}
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}
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