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|
#![feature(test)]
extern crate test;
use std::sync::Barrier;
use crossbeam_utils::atomic::AtomicCell;
use crossbeam_utils::thread;
#[bench]
fn load_u8(b: &mut test::Bencher) {
let a = AtomicCell::new(0u8);
let mut sum = 0;
b.iter(|| sum += a.load());
test::black_box(sum);
}
#[bench]
fn store_u8(b: &mut test::Bencher) {
let a = AtomicCell::new(0u8);
b.iter(|| a.store(1));
}
#[bench]
fn fetch_add_u8(b: &mut test::Bencher) {
let a = AtomicCell::new(0u8);
b.iter(|| a.fetch_add(1));
}
#[bench]
fn compare_exchange_u8(b: &mut test::Bencher) {
let a = AtomicCell::new(0u8);
let mut i = 0;
b.iter(|| {
let _ = a.compare_exchange(i, i.wrapping_add(1));
i = i.wrapping_add(1);
});
}
#[bench]
fn concurrent_load_u8(b: &mut test::Bencher) {
const THREADS: usize = 2;
const STEPS: usize = 1_000_000;
let start = Barrier::new(THREADS + 1);
let end = Barrier::new(THREADS + 1);
let exit = AtomicCell::new(false);
let a = AtomicCell::new(0u8);
thread::scope(|scope| {
for _ in 0..THREADS {
scope.spawn(|_| loop {
start.wait();
let mut sum = 0;
for _ in 0..STEPS {
sum += a.load();
}
test::black_box(sum);
end.wait();
if exit.load() {
break;
}
});
}
start.wait();
end.wait();
b.iter(|| {
start.wait();
end.wait();
});
start.wait();
exit.store(true);
end.wait();
})
.unwrap();
}
#[bench]
fn load_usize(b: &mut test::Bencher) {
let a = AtomicCell::new(0usize);
let mut sum = 0;
b.iter(|| sum += a.load());
test::black_box(sum);
}
#[bench]
fn store_usize(b: &mut test::Bencher) {
let a = AtomicCell::new(0usize);
b.iter(|| a.store(1));
}
#[bench]
fn fetch_add_usize(b: &mut test::Bencher) {
let a = AtomicCell::new(0usize);
b.iter(|| a.fetch_add(1));
}
#[bench]
fn compare_exchange_usize(b: &mut test::Bencher) {
let a = AtomicCell::new(0usize);
let mut i = 0;
b.iter(|| {
let _ = a.compare_exchange(i, i.wrapping_add(1));
i = i.wrapping_add(1);
});
}
#[bench]
fn concurrent_load_usize(b: &mut test::Bencher) {
const THREADS: usize = 2;
const STEPS: usize = 1_000_000;
let start = Barrier::new(THREADS + 1);
let end = Barrier::new(THREADS + 1);
let exit = AtomicCell::new(false);
let a = AtomicCell::new(0usize);
thread::scope(|scope| {
for _ in 0..THREADS {
scope.spawn(|_| loop {
start.wait();
let mut sum = 0;
for _ in 0..STEPS {
sum += a.load();
}
test::black_box(sum);
end.wait();
if exit.load() {
break;
}
});
}
start.wait();
end.wait();
b.iter(|| {
start.wait();
end.wait();
});
start.wait();
exit.store(true);
end.wait();
})
.unwrap();
}
|
