From d3c4e4a20a05085eae8d568c7efdbe09bada9cf5 Mon Sep 17 00:00:00 2001 From: Dario Nieuwenhuis Date: Mon, 3 Apr 2023 01:18:27 +0200 Subject: executor: add Pender, rework Cargo features. This introduces a `Pender` struct with enum cases for thread-mode, interrupt-mode and custom callback executors. This avoids calls through function pointers when using only the thread or interrupt executors. Faster, and friendlier to `cargo-call-stack`. `embassy-executor` now has `arch-xxx` Cargo features to select the arch and to enable the builtin executors (thread and interrupt). --- embassy-executor/src/arch/wasm.rs | 134 +++++++++++++++++++++----------------- 1 file changed, 74 insertions(+), 60 deletions(-) (limited to 'embassy-executor/src/arch/wasm.rs') diff --git a/embassy-executor/src/arch/wasm.rs b/embassy-executor/src/arch/wasm.rs index 98091cfbb..08ab16b99 100644 --- a/embassy-executor/src/arch/wasm.rs +++ b/embassy-executor/src/arch/wasm.rs @@ -1,74 +1,88 @@ -use core::marker::PhantomData; +#[cfg(feature = "executor-interrupt")] +compile_error!("`executor-interrupt` is not supported with `arch-wasm`."); -use js_sys::Promise; -use wasm_bindgen::prelude::*; +#[cfg(feature = "executor-thread")] +pub use thread::*; +#[cfg(feature = "executor-thread")] +mod thread { -use super::raw::util::UninitCell; -use super::raw::{self}; -use super::Spawner; + use core::marker::PhantomData; -/// WASM executor, wasm_bindgen to schedule tasks on the JS event loop. -pub struct Executor { - inner: raw::Executor, - ctx: &'static WasmContext, - not_send: PhantomData<*mut ()>, -} + #[cfg(feature = "nightly")] + pub use embassy_macros::main_wasm as main; + use js_sys::Promise; + use wasm_bindgen::prelude::*; -pub(crate) struct WasmContext { - promise: Promise, - closure: UninitCell>, -} + use crate::raw::util::UninitCell; + use crate::raw::{Pender, PenderInner}; + use crate::{raw, Spawner}; + + /// WASM executor, wasm_bindgen to schedule tasks on the JS event loop. + pub struct Executor { + inner: raw::Executor, + ctx: &'static WasmContext, + not_send: PhantomData<*mut ()>, + } + + pub(crate) struct WasmContext { + promise: Promise, + closure: UninitCell>, + } + + #[derive(Copy, Clone)] + pub(crate) struct ThreadPender(&'static WasmContext); -impl WasmContext { - pub fn new() -> Self { - Self { - promise: Promise::resolve(&JsValue::undefined()), - closure: UninitCell::uninit(), + impl ThreadPender { + #[allow(unused)] + pub(crate) fn pend(self) { + let _ = self.0.promise.then(unsafe { self.0.closure.as_mut() }); } } -} -impl Executor { - /// Create a new Executor. - pub fn new() -> Self { - let ctx = &*Box::leak(Box::new(WasmContext::new())); - let inner = raw::Executor::new( - |p| unsafe { - let ctx = &*(p as *const () as *const WasmContext); - let _ = ctx.promise.then(ctx.closure.as_mut()); - }, - ctx as *const _ as _, - ); - Self { - inner, - not_send: PhantomData, - ctx, + impl WasmContext { + pub fn new() -> Self { + Self { + promise: Promise::resolve(&JsValue::undefined()), + closure: UninitCell::uninit(), + } } } - /// Run the executor. - /// - /// The `init` closure is called with a [`Spawner`] that spawns tasks on - /// this executor. Use it to spawn the initial task(s). After `init` returns, - /// the executor starts running the tasks. - /// - /// To spawn more tasks later, you may keep copies of the [`Spawner`] (it is `Copy`), - /// for example by passing it as an argument to the initial tasks. - /// - /// This function requires `&'static mut self`. This means you have to store the - /// Executor instance in a place where it'll live forever and grants you mutable - /// access. There's a few ways to do this: - /// - /// - a [StaticCell](https://docs.rs/static_cell/latest/static_cell/) (safe) - /// - a `static mut` (unsafe) - /// - a local variable in a function you know never returns (like `fn main() -> !`), upgrading its lifetime with `transmute`. (unsafe) - pub fn start(&'static mut self, init: impl FnOnce(Spawner)) { - unsafe { - let executor = &self.inner; - self.ctx.closure.write(Closure::new(move |_| { - executor.poll(); - })); - init(self.inner.spawner()); + impl Executor { + /// Create a new Executor. + pub fn new() -> Self { + let ctx = &*Box::leak(Box::new(WasmContext::new())); + Self { + inner: raw::Executor::new(Pender(PenderInner::Thread(ThreadPender(ctx)))), + not_send: PhantomData, + ctx, + } + } + + /// Run the executor. + /// + /// The `init` closure is called with a [`Spawner`] that spawns tasks on + /// this executor. Use it to spawn the initial task(s). After `init` returns, + /// the executor starts running the tasks. + /// + /// To spawn more tasks later, you may keep copies of the [`Spawner`] (it is `Copy`), + /// for example by passing it as an argument to the initial tasks. + /// + /// This function requires `&'static mut self`. This means you have to store the + /// Executor instance in a place where it'll live forever and grants you mutable + /// access. There's a few ways to do this: + /// + /// - a [StaticCell](https://docs.rs/static_cell/latest/static_cell/) (safe) + /// - a `static mut` (unsafe) + /// - a local variable in a function you know never returns (like `fn main() -> !`), upgrading its lifetime with `transmute`. (unsafe) + pub fn start(&'static mut self, init: impl FnOnce(Spawner)) { + unsafe { + let executor = &self.inner; + self.ctx.closure.write(Closure::new(move |_| { + executor.poll(); + })); + init(self.inner.spawner()); + } } } } -- cgit