commit | 7906bc32039ac241ecdea3103d385e3638a98c6a | [log] [tgz] |
---|---|---|
author | Wei Li <[email protected]> | Tue Jul 30 03:08:43 2024 +0000 |
committer | Automerger Merge Worker <[email protected]> | Tue Jul 30 03:08:43 2024 +0000 |
tree | 29e18deab09288f9026364f6c0acd00e0fa08acc | |
parent | c55ccc0ec60824bb750f90a41bfbf229995a1cf9 [diff] | |
parent | b7699de3f38e6f21edaae728e7ab20e95eff89ef [diff] |
Cleanup license metadata in external/rust/crates/async-task. am: 4ee9c3937b am: b7699de3f3 Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/async-task/+/3194638 Change-Id: Iec0e70d44ae092e4b23ab2a3074d6eaf7d27e21b Signed-off-by: Automerger Merge Worker <[email protected]>
Task abstraction for building executors.
To spawn a future onto an executor, we first need to allocate it on the heap and keep some state attached to it. The state indicates whether the future is ready for polling, waiting to be woken up, or completed. Such a stateful future is called a task.
All executors have a queue that holds scheduled tasks:
let (sender, receiver) = flume::unbounded();
A task is created using either spawn()
, spawn_local()
, or spawn_unchecked()
which return a Runnable
and a Task
:
// A future that will be spawned. let future = async { 1 + 2 }; // A function that schedules the task when it gets woken up. let schedule = move |runnable| sender.send(runnable).unwrap(); // Construct a task. let (runnable, task) = async_task::spawn(future, schedule); // Push the task into the queue by invoking its schedule function. runnable.schedule();
The Runnable
is used to poll the task's future, and the Task
is used to await its output.
Finally, we need a loop that takes scheduled tasks from the queue and runs them:
for runnable in receiver { runnable.run(); }
Method run()
polls the task's future once. Then, the Runnable
vanishes and only reappears when its Waker
wakes the task, thus scheduling it to be run again.
Licensed under either of
at your option.
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.