commit | 112b5a7240500eb1470adae5ac2387a24f6cc511 | [log] [tgz] |
---|---|---|
author | Jeff Vander Stoep <jeffv@google.com> | Wed Dec 07 15:06:14 2022 +0000 |
committer | Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com> | Wed Dec 07 15:06:14 2022 +0000 |
tree | 95f761b82903c457793f4c2026890653158214f3 | |
parent | 70ae0a6720d62d2e0743d9d3133239f8aa9180d2 [diff] | |
parent | 7e4ae427a170c6085f7ee38d2b9ad1141f711c36 [diff] |
Upgrade async_task to 4.3.0 am: 1d8091d3e6 am: 7e800aec6e am: 7e4ae427a1 Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/async-task/+/2327654 Change-Id: I52f2b241917e6376bcc7bff9796c8bb92e0b09a0 Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
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.