From 69cee08c0e60ee35d1179046c19139c745424406 Mon Sep 17 00:00:00 2001 From: MiniaczQ Date: Mon, 21 Mar 2022 23:37:02 +0100 Subject: [PATCH 1/2] =?UTF-8?q?Adi=C3=B3s?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- crates/bevy_tasks/src/countdown_event.rs | 134 ----------------------- 1 file changed, 134 deletions(-) delete mode 100644 crates/bevy_tasks/src/countdown_event.rs diff --git a/crates/bevy_tasks/src/countdown_event.rs b/crates/bevy_tasks/src/countdown_event.rs deleted file mode 100644 index e9c9c66401e4e..0000000000000 --- a/crates/bevy_tasks/src/countdown_event.rs +++ /dev/null @@ -1,134 +0,0 @@ -use event_listener::Event; -use std::sync::{ - atomic::{AtomicIsize, Ordering}, - Arc, -}; - -#[derive(Debug)] -struct CountdownEventInner { - /// Async primitive that can be awaited and signalled. We fire it when counter hits 0. - event: Event, - - /// The number of decrements remaining - counter: AtomicIsize, -} - -/// A counter that starts with an initial count `n`. Once it is decremented `n` times, it will be -/// "ready". Call `listen` to get a future that can be awaited. -#[derive(Clone, Debug)] -pub struct CountdownEvent { - inner: Arc, -} - -impl CountdownEvent { - /// Creates a [`CountdownEvent`] that must be decremented `n` times for listeners to be - /// signalled - pub fn new(n: isize) -> Self { - let inner = CountdownEventInner { - event: Event::new(), - counter: AtomicIsize::new(n), - }; - - CountdownEvent { - inner: Arc::new(inner), - } - } - - /// Get the number of times decrement must be called to trigger notifying all listeners - pub fn get(&self) -> isize { - self.inner.counter.load(Ordering::Acquire) - } - - /// Decrement the counter by one. If this is the Nth call, trigger all listeners - pub fn decrement(&self) { - // If we are the last decrementer, notify listeners - let value = self.inner.counter.fetch_sub(1, Ordering::AcqRel); - if value <= 1 { - self.inner.event.notify(std::usize::MAX); - - // Reset to 0 - wrapping an isize negative seems unlikely but should probably do it - // anyways. - self.inner.counter.store(0, Ordering::Release); - } - } - - /// Resets the counter. Any listens following this point will not be notified until decrement - /// is called N times - pub fn reset(&self, n: isize) { - self.inner.counter.store(n, Ordering::Release); - } - - /// Awaits decrement being called N times - pub async fn listen(&self) { - let mut listener = None; - - // The complexity here is due to Event not necessarily signalling awaits that are placed - // after the await is called. So we must check the counter AFTER taking a listener. - loop { - // We're done, break - if self.inner.counter.load(Ordering::Acquire) <= 0 { - break; - } - - match listener.take() { - None => { - listener = Some(self.inner.event.listen()); - } - Some(l) => { - l.await; - } - } - } - } -} - -#[cfg(test)] -mod tests { - use super::*; - - #[test] - fn countdown_event_ready_after() { - let countdown_event = CountdownEvent::new(2); - countdown_event.decrement(); - countdown_event.decrement(); - futures_lite::future::block_on(countdown_event.listen()); - } - - #[test] - fn countdown_event_ready() { - let countdown_event = CountdownEvent::new(2); - countdown_event.decrement(); - let countdown_event_clone = countdown_event.clone(); - let handle = std::thread::spawn(move || { - futures_lite::future::block_on(countdown_event_clone.listen()); - }); - - // Pause to give the new thread time to start blocking (ugly hack) - std::thread::sleep(instant::Duration::from_millis(100)); - - countdown_event.decrement(); - handle.join().unwrap(); - } - - #[test] - fn event_resets_if_listeners_are_cleared() { - let event = Event::new(); - - // notify all listeners - let listener1 = event.listen(); - event.notify(std::usize::MAX); - futures_lite::future::block_on(listener1); - - // If all listeners are notified, the structure should now be cleared. We're free to listen - // again - let listener2 = event.listen(); - let listener3 = event.listen(); - - // Verify that we are still blocked - assert!(!listener2.wait_timeout(instant::Duration::from_millis(10))); - - // Notify all and verify the remaining listener is notified - event.notify(std::usize::MAX); - futures_lite::future::block_on(listener3); - } -} From 1de741e75c3552fa16072bc18e8e3d221f782a7d Mon Sep 17 00:00:00 2001 From: MiniaczQ Date: Mon, 21 Mar 2022 23:37:47 +0100 Subject: [PATCH 2/2] forgot this --- crates/bevy_tasks/src/lib.rs | 3 --- 1 file changed, 3 deletions(-) diff --git a/crates/bevy_tasks/src/lib.rs b/crates/bevy_tasks/src/lib.rs index d4e8d9dfe1367..7345d775ee968 100644 --- a/crates/bevy_tasks/src/lib.rs +++ b/crates/bevy_tasks/src/lib.rs @@ -20,9 +20,6 @@ pub use single_threaded_task_pool::{Scope, TaskPool, TaskPoolBuilder}; mod usages; pub use usages::{AsyncComputeTaskPool, ComputeTaskPool, IoTaskPool}; -mod countdown_event; -pub use countdown_event::CountdownEvent; - mod iter; pub use iter::ParallelIterator;