diff options
Diffstat (limited to 'third_party/rust/crossbeam-utils/tests/sharded_lock.rs')
| -rw-r--r-- | third_party/rust/crossbeam-utils/tests/sharded_lock.rs | 252 |
1 files changed, 252 insertions, 0 deletions
diff --git a/third_party/rust/crossbeam-utils/tests/sharded_lock.rs b/third_party/rust/crossbeam-utils/tests/sharded_lock.rs new file mode 100644 index 0000000000..002f7f5e19 --- /dev/null +++ b/third_party/rust/crossbeam-utils/tests/sharded_lock.rs @@ -0,0 +1,252 @@ +use std::sync::atomic::{AtomicUsize, Ordering}; +use std::sync::mpsc::channel; +use std::sync::{Arc, TryLockError}; +use std::thread; + +use crossbeam_utils::sync::ShardedLock; +use rand::Rng; + +#[derive(Eq, PartialEq, Debug)] +struct NonCopy(i32); + +#[test] +fn smoke() { + let l = ShardedLock::new(()); + drop(l.read().unwrap()); + drop(l.write().unwrap()); + drop((l.read().unwrap(), l.read().unwrap())); + drop(l.write().unwrap()); +} + +#[test] +fn frob() { + const N: u32 = 10; + #[cfg(miri)] + const M: usize = 50; + #[cfg(not(miri))] + const M: usize = 1000; + + let r = Arc::new(ShardedLock::new(())); + + let (tx, rx) = channel::<()>(); + for _ in 0..N { + let tx = tx.clone(); + let r = r.clone(); + thread::spawn(move || { + let mut rng = rand::thread_rng(); + for _ in 0..M { + if rng.gen_bool(1.0 / (N as f64)) { + drop(r.write().unwrap()); + } else { + drop(r.read().unwrap()); + } + } + drop(tx); + }); + } + drop(tx); + let _ = rx.recv(); +} + +#[test] +fn arc_poison_wr() { + let arc = Arc::new(ShardedLock::new(1)); + let arc2 = arc.clone(); + let _: Result<(), _> = thread::spawn(move || { + let _lock = arc2.write().unwrap(); + panic!(); + }) + .join(); + assert!(arc.read().is_err()); +} + +#[test] +fn arc_poison_ww() { + let arc = Arc::new(ShardedLock::new(1)); + assert!(!arc.is_poisoned()); + let arc2 = arc.clone(); + let _: Result<(), _> = thread::spawn(move || { + let _lock = arc2.write().unwrap(); + panic!(); + }) + .join(); + assert!(arc.write().is_err()); + assert!(arc.is_poisoned()); +} + +#[test] +fn arc_no_poison_rr() { + let arc = Arc::new(ShardedLock::new(1)); + let arc2 = arc.clone(); + let _: Result<(), _> = thread::spawn(move || { + let _lock = arc2.read().unwrap(); + panic!(); + }) + .join(); + let lock = arc.read().unwrap(); + assert_eq!(*lock, 1); +} +#[test] +fn arc_no_poison_sl() { + let arc = Arc::new(ShardedLock::new(1)); + let arc2 = arc.clone(); + let _: Result<(), _> = thread::spawn(move || { + let _lock = arc2.read().unwrap(); + panic!() + }) + .join(); + let lock = arc.write().unwrap(); + assert_eq!(*lock, 1); +} + +#[test] +fn arc() { + let arc = Arc::new(ShardedLock::new(0)); + let arc2 = arc.clone(); + let (tx, rx) = channel(); + + thread::spawn(move || { + let mut lock = arc2.write().unwrap(); + for _ in 0..10 { + let tmp = *lock; + *lock = -1; + thread::yield_now(); + *lock = tmp + 1; + } + tx.send(()).unwrap(); + }); + + // Readers try to catch the writer in the act + let mut children = Vec::new(); + for _ in 0..5 { + let arc3 = arc.clone(); + children.push(thread::spawn(move || { + let lock = arc3.read().unwrap(); + assert!(*lock >= 0); + })); + } + + // Wait for children to pass their asserts + for r in children { + assert!(r.join().is_ok()); + } + + // Wait for writer to finish + rx.recv().unwrap(); + let lock = arc.read().unwrap(); + assert_eq!(*lock, 10); +} + +#[test] +fn arc_access_in_unwind() { + let arc = Arc::new(ShardedLock::new(1)); + let arc2 = arc.clone(); + let _ = thread::spawn(move || { + struct Unwinder { + i: Arc<ShardedLock<isize>>, + } + impl Drop for Unwinder { + fn drop(&mut self) { + let mut lock = self.i.write().unwrap(); + *lock += 1; + } + } + let _u = Unwinder { i: arc2 }; + panic!(); + }) + .join(); + let lock = arc.read().unwrap(); + assert_eq!(*lock, 2); +} + +#[test] +fn unsized_type() { + let sl: &ShardedLock<[i32]> = &ShardedLock::new([1, 2, 3]); + { + let b = &mut *sl.write().unwrap(); + b[0] = 4; + b[2] = 5; + } + let comp: &[i32] = &[4, 2, 5]; + assert_eq!(&*sl.read().unwrap(), comp); +} + +#[test] +fn try_write() { + let lock = ShardedLock::new(0isize); + let read_guard = lock.read().unwrap(); + + let write_result = lock.try_write(); + match write_result { + Err(TryLockError::WouldBlock) => (), + Ok(_) => panic!("try_write should not succeed while read_guard is in scope"), + Err(_) => panic!("unexpected error"), + } + + drop(read_guard); +} + +#[test] +fn test_into_inner() { + let m = ShardedLock::new(NonCopy(10)); + assert_eq!(m.into_inner().unwrap(), NonCopy(10)); +} + +#[test] +fn test_into_inner_drop() { + struct Foo(Arc<AtomicUsize>); + impl Drop for Foo { + fn drop(&mut self) { + self.0.fetch_add(1, Ordering::SeqCst); + } + } + let num_drops = Arc::new(AtomicUsize::new(0)); + let m = ShardedLock::new(Foo(num_drops.clone())); + assert_eq!(num_drops.load(Ordering::SeqCst), 0); + { + let _inner = m.into_inner().unwrap(); + assert_eq!(num_drops.load(Ordering::SeqCst), 0); + } + assert_eq!(num_drops.load(Ordering::SeqCst), 1); +} + +#[test] +fn test_into_inner_poison() { + let m = Arc::new(ShardedLock::new(NonCopy(10))); + let m2 = m.clone(); + let _ = thread::spawn(move || { + let _lock = m2.write().unwrap(); + panic!("test panic in inner thread to poison ShardedLock"); + }) + .join(); + + assert!(m.is_poisoned()); + match Arc::try_unwrap(m).unwrap().into_inner() { + Err(e) => assert_eq!(e.into_inner(), NonCopy(10)), + Ok(x) => panic!("into_inner of poisoned ShardedLock is Ok: {:?}", x), + } +} + +#[test] +fn test_get_mut() { + let mut m = ShardedLock::new(NonCopy(10)); + *m.get_mut().unwrap() = NonCopy(20); + assert_eq!(m.into_inner().unwrap(), NonCopy(20)); +} + +#[test] +fn test_get_mut_poison() { + let m = Arc::new(ShardedLock::new(NonCopy(10))); + let m2 = m.clone(); + let _ = thread::spawn(move || { + let _lock = m2.write().unwrap(); + panic!("test panic in inner thread to poison ShardedLock"); + }) + .join(); + + assert!(m.is_poisoned()); + match Arc::try_unwrap(m).unwrap().get_mut() { + Err(e) => assert_eq!(*e.into_inner(), NonCopy(10)), + Ok(x) => panic!("get_mut of poisoned ShardedLock is Ok: {:?}", x), + } +} |