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|
use crate::io::driver::ScheduledIo;
use crate::util::slab::{Address, Slab};
use loom::sync::{Arc, Condvar, Mutex};
use loom::thread;
#[test]
fn local_remove() {
loom::model(|| {
let slab = Arc::new(Slab::new());
let s = slab.clone();
let t1 = thread::spawn(move || {
let idx = store_val(&s, 1);
assert_eq!(get_val(&s, idx), Some(1));
s.remove(idx);
assert_eq!(get_val(&s, idx), None);
let idx = store_val(&s, 2);
assert_eq!(get_val(&s, idx), Some(2));
s.remove(idx);
assert_eq!(get_val(&s, idx), None);
});
let s = slab.clone();
let t2 = thread::spawn(move || {
let idx = store_val(&s, 3);
assert_eq!(get_val(&s, idx), Some(3));
s.remove(idx);
assert_eq!(get_val(&s, idx), None);
let idx = store_val(&s, 4);
s.remove(idx);
assert_eq!(get_val(&s, idx), None);
});
let s = slab;
let idx1 = store_val(&s, 5);
assert_eq!(get_val(&s, idx1), Some(5));
let idx2 = store_val(&s, 6);
assert_eq!(get_val(&s, idx2), Some(6));
s.remove(idx1);
assert_eq!(get_val(&s, idx1), None);
assert_eq!(get_val(&s, idx2), Some(6));
s.remove(idx2);
assert_eq!(get_val(&s, idx2), None);
t1.join().expect("thread 1 should not panic");
t2.join().expect("thread 2 should not panic");
});
}
#[test]
fn remove_remote() {
loom::model(|| {
let slab = Arc::new(Slab::new());
let idx1 = store_val(&slab, 1);
assert_eq!(get_val(&slab, idx1), Some(1));
let idx2 = store_val(&slab, 2);
assert_eq!(get_val(&slab, idx2), Some(2));
let idx3 = store_val(&slab, 3);
assert_eq!(get_val(&slab, idx3), Some(3));
let s = slab.clone();
let t1 = thread::spawn(move || {
assert_eq!(get_val(&s, idx2), Some(2));
s.remove(idx2);
assert_eq!(get_val(&s, idx2), None);
});
let s = slab.clone();
let t2 = thread::spawn(move || {
assert_eq!(get_val(&s, idx3), Some(3));
s.remove(idx3);
assert_eq!(get_val(&s, idx3), None);
});
t1.join().expect("thread 1 should not panic");
t2.join().expect("thread 2 should not panic");
assert_eq!(get_val(&slab, idx1), Some(1));
assert_eq!(get_val(&slab, idx2), None);
assert_eq!(get_val(&slab, idx3), None);
});
}
#[test]
fn remove_remote_and_reuse() {
loom::model(|| {
let slab = Arc::new(Slab::new());
let idx1 = store_val(&slab, 1);
let idx2 = store_val(&slab, 2);
assert_eq!(get_val(&slab, idx1), Some(1));
assert_eq!(get_val(&slab, idx2), Some(2));
let s = slab.clone();
let t1 = thread::spawn(move || {
s.remove(idx1);
let value = get_val(&s, idx1);
// We may or may not see the new value yet, depending on when
// this occurs, but we must either see the new value or `None`;
// the old value has been removed!
assert!(value == None || value == Some(3));
});
let idx3 = store_when_free(&slab, 3);
t1.join().expect("thread 1 should not panic");
assert_eq!(get_val(&slab, idx3), Some(3));
assert_eq!(get_val(&slab, idx2), Some(2));
});
}
#[test]
fn concurrent_alloc_remove() {
loom::model(|| {
let slab = Arc::new(Slab::new());
let pair = Arc::new((Mutex::new(None), Condvar::new()));
let slab2 = slab.clone();
let pair2 = pair.clone();
let remover = thread::spawn(move || {
let (lock, cvar) = &*pair2;
for _ in 0..2 {
let mut next = lock.lock().unwrap();
while next.is_none() {
next = cvar.wait(next).unwrap();
}
let key = next.take().unwrap();
slab2.remove(key);
assert_eq!(get_val(&slab2, key), None);
cvar.notify_one();
}
});
let (lock, cvar) = &*pair;
for i in 0..2 {
let key = store_val(&slab, i);
let mut next = lock.lock().unwrap();
*next = Some(key);
cvar.notify_one();
// Wait for the item to be removed.
while next.is_some() {
next = cvar.wait(next).unwrap();
}
assert_eq!(get_val(&slab, key), None);
}
remover.join().unwrap();
})
}
#[test]
fn concurrent_remove_remote_and_reuse() {
loom::model(|| {
let slab = Arc::new(Slab::new());
let idx1 = store_val(&slab, 1);
let idx2 = store_val(&slab, 2);
assert_eq!(get_val(&slab, idx1), Some(1));
assert_eq!(get_val(&slab, idx2), Some(2));
let s = slab.clone();
let s2 = slab.clone();
let t1 = thread::spawn(move || {
s.remove(idx1);
});
let t2 = thread::spawn(move || {
s2.remove(idx2);
});
let idx3 = store_when_free(&slab, 3);
t1.join().expect("thread 1 should not panic");
t2.join().expect("thread 1 should not panic");
assert!(get_val(&slab, idx1).is_none());
assert!(get_val(&slab, idx2).is_none());
assert_eq!(get_val(&slab, idx3), Some(3));
});
}
#[test]
fn alloc_remove_get() {
loom::model(|| {
let slab = Arc::new(Slab::new());
let pair = Arc::new((Mutex::new(None), Condvar::new()));
let slab2 = slab.clone();
let pair2 = pair.clone();
let t1 = thread::spawn(move || {
let slab = slab2;
let (lock, cvar) = &*pair2;
// allocate one entry just so that we have to use the final one for
// all future allocations.
let _key0 = store_val(&slab, 0);
let key = store_val(&slab, 1);
let mut next
|
