diff options
Diffstat (limited to 'src/runtime/scheduler/defer.rs')
-rw-r--r-- | src/runtime/scheduler/defer.rs | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/src/runtime/scheduler/defer.rs b/src/runtime/scheduler/defer.rs new file mode 100644 index 0000000..a4be8ef --- /dev/null +++ b/src/runtime/scheduler/defer.rs @@ -0,0 +1,43 @@ +use std::cell::RefCell; +use std::task::Waker; + +pub(crate) struct Defer { + deferred: RefCell<Vec<Waker>>, +} + +impl Defer { + pub(crate) fn new() -> Defer { + Defer { + deferred: Default::default(), + } + } + + pub(crate) fn defer(&self, waker: &Waker) { + let mut deferred = self.deferred.borrow_mut(); + + // If the same task adds itself a bunch of times, then only add it once. + if let Some(last) = deferred.last() { + if last.will_wake(waker) { + return; + } + } + + deferred.push(waker.clone()); + } + + pub(crate) fn is_empty(&self) -> bool { + self.deferred.borrow().is_empty() + } + + pub(crate) fn wake(&self) { + while let Some(waker) = self.deferred.borrow_mut().pop() { + waker.wake(); + } + } + + #[cfg(tokio_taskdump)] + pub(crate) fn take_deferred(&self) -> Vec<Waker> { + let mut deferred = self.deferred.borrow_mut(); + std::mem::take(&mut *deferred) + } +} |