Remove interrupt executor, remove PenderContext

This commit is contained in:
Dániel Buga 2023-08-14 15:59:47 +02:00
parent 3a51e2d9ca
commit 9954346143
8 changed files with 19 additions and 164 deletions

View File

@ -2,12 +2,12 @@ const THREAD_PENDER: usize = usize::MAX;
#[export_name = "__pender"]
#[cfg(any(feature = "executor-thread", feature = "executor-interrupt"))]
fn __pender(context: crate::raw::PenderContext) {
fn __pender(context: *mut ()) {
unsafe {
// Safety: `context` is either `usize::MAX` created by `Executor::run`, or a valid interrupt
// request number given to `InterruptExecutor::start`.
let context: usize = core::mem::transmute(context);
let context = context as usize;
#[cfg(feature = "executor-thread")]
if context == THREAD_PENDER {
@ -75,7 +75,7 @@ mod thread {
/// Create a new Executor.
pub fn new() -> Self {
Self {
inner: raw::Executor::new(unsafe { core::mem::transmute(THREAD_PENDER) }),
inner: raw::Executor::new(THREAD_PENDER as *mut ()),
not_send: PhantomData,
}
}
@ -205,10 +205,9 @@ mod interrupt {
}
unsafe {
let context = core::mem::transmute(irq.number() as usize);
(&mut *self.executor.get())
.as_mut_ptr()
.write(raw::Executor::new(context))
.write(raw::Executor::new(irq.number() as *mut ()))
}
let executor = unsafe { (&*self.executor.get()).assume_init_ref() };

View File

@ -17,7 +17,7 @@ mod thread {
static SIGNAL_WORK_THREAD_MODE: AtomicBool = AtomicBool::new(false);
#[export_name = "__pender"]
fn __thread_mode_pender(_context: crate::raw::PenderContext) {
fn __thread_mode_pender(_context: *mut ()) {
SIGNAL_WORK_THREAD_MODE.store(true, Ordering::SeqCst);
}
@ -31,7 +31,7 @@ mod thread {
/// Create a new Executor.
pub fn new() -> Self {
Self {
inner: raw::Executor::new(unsafe { core::mem::transmute(0) }),
inner: raw::Executor::new(core::ptr::null_mut()),
not_send: PhantomData,
}
}

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@ -14,7 +14,7 @@ mod thread {
use crate::{raw, Spawner};
#[export_name = "__pender"]
fn __pender(context: crate::raw::PenderContext) {
fn __pender(context: *mut ()) {
let signaler: &'static Signaler = unsafe { std::mem::transmute(context) };
signaler.signal()
}
@ -29,9 +29,9 @@ mod thread {
impl Executor {
/// Create a new Executor.
pub fn new() -> Self {
let signaler = &*Box::leak(Box::new(Signaler::new()));
let signaler = Box::leak(Box::new(Signaler::new()));
Self {
inner: raw::Executor::new(unsafe { std::mem::transmute(signaler) }),
inner: raw::Executor::new(signaler as *mut Signaler as *mut ()),
not_send: PhantomData,
signaler,
}

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@ -14,11 +14,10 @@ mod thread {
use wasm_bindgen::prelude::*;
use crate::raw::util::UninitCell;
use crate::raw::PenderContext;
use crate::{raw, Spawner};
#[export_name = "__thread_mode_pender"]
fn __thread_mode_pender(context: PenderContext) {
fn __thread_mode_pender(context: *mut ()) {
let signaler: &'static WasmContext = unsafe { std::mem::transmute(context) };
let _ = signaler.promise.then(unsafe { signaler.closure.as_mut() });
}
@ -47,9 +46,9 @@ mod thread {
impl Executor {
/// Create a new Executor.
pub fn new() -> Self {
let ctx = &*Box::leak(Box::new(WasmContext::new()));
let ctx = Box::leak(Box::new(WasmContext::new()));
Self {
inner: raw::Executor::new(unsafe { core::mem::transmute(ctx) }),
inner: raw::Executor::new(ctx as *mut WasmContext as *mut ()),
ctx,
not_send: PhantomData,
}

View File

@ -14,7 +14,7 @@ mod thread {
static SIGNAL_WORK_THREAD_MODE: AtomicBool = AtomicBool::new(false);
#[export_name = "__thread_mode_pender"]
fn __thread_mode_pender(_context: crate::raw::PenderContext) {
fn __thread_mode_pender(_context: *mut ()) {
SIGNAL_WORK_THREAD_MODE.store(true, Ordering::SeqCst);
}
@ -28,7 +28,7 @@ mod thread {
/// Create a new Executor.
pub fn new() -> Self {
Self {
inner: raw::Executor::new(unsafe { core::mem::transmute(0) }),
inner: raw::Executor::new(core::ptr::null_mut()),
not_send: PhantomData,
}
}

View File

@ -1,131 +0,0 @@
//! Interrupt-mode executor.
use core::cell::UnsafeCell;
use core::mem::MaybeUninit;
use atomic_polyfill::{AtomicBool, Ordering};
use crate::raw::{self, PenderContext};
/// Architecture-specific interface for an interrupt-mode executor. This trait describes what data
/// should be passed to the [`InterruptExecutor`]'s pender, and how to enable the interrupt that
/// triggers polling the executor.
// TODO: Name pending
pub trait InterruptContext {
/// A pointer-sized piece of data that is passed to the pender function.
///
/// Usually, the context contains the interrupt that should be used to wake the executor.
fn context(&self) -> PenderContext;
/// Enabled the interrupt request.
fn enable(&self);
}
/// Interrupt mode executor.
///
/// This executor runs tasks in interrupt mode. The interrupt handler is set up
/// to poll tasks, and when a task is woken the interrupt is pended from software.
///
/// This allows running async tasks at a priority higher than thread mode. One
/// use case is to leave thread mode free for non-async tasks. Another use case is
/// to run multiple executors: one in thread mode for low priority tasks and another in
/// interrupt mode for higher priority tasks. Higher priority tasks will preempt lower
/// priority ones.
///
/// It is even possible to run multiple interrupt mode executors at different priorities,
/// by assigning different priorities to the interrupts. For an example on how to do this,
/// See the 'multiprio' example for 'embassy-nrf'.
///
/// To use it, you have to pick an interrupt that won't be used by the hardware.
/// Some chips reserve some interrupts for this purpose, sometimes named "software interrupts" (SWI).
/// If this is not the case, you may use an interrupt from any unused peripheral.
///
/// It is somewhat more complex to use, it's recommended to use the
/// thread-mode executor instead, if it works for your use case.
pub struct InterruptModeExecutor {
started: AtomicBool,
executor: UnsafeCell<MaybeUninit<raw::Executor>>,
}
unsafe impl Send for InterruptModeExecutor {}
unsafe impl Sync for InterruptModeExecutor {}
impl InterruptModeExecutor {
/// Create a new, not started `InterruptExecutor`.
#[inline]
pub const fn new() -> Self {
Self {
started: AtomicBool::new(false),
executor: UnsafeCell::new(MaybeUninit::uninit()),
}
}
/// Executor interrupt callback.
///
/// # Safety
///
/// You MUST call this from the interrupt handler, and from nowhere else.
pub unsafe fn on_interrupt(&'static self) {
let executor = unsafe { (&*self.executor.get()).assume_init_ref() };
executor.poll();
}
/// Start the executor.
///
/// This initializes the executor, enables the interrupt, and returns.
/// The executor keeps running in the background through the interrupt.
///
/// This returns a [`SendSpawner`] you can use to spawn tasks on it. A [`SendSpawner`]
/// is returned instead of a [`Spawner`](embassy_executor::Spawner) because the executor effectively runs in a
/// different "thread" (the interrupt), so spawning tasks on it is effectively
/// sending them.
///
/// To obtain a [`Spawner`](embassy_executor::Spawner) for this executor, use [`Spawner::for_current_executor()`](embassy_executor::Spawner::for_current_executor()) from
/// a task running in it.
///
/// # Interrupt requirements
///
/// You must write the interrupt handler yourself, and make it call [`on_interrupt()`](Self::on_interrupt).
///
/// This method already enables (unmasks) the interrupt, you must NOT do it yourself.
///
/// You must set the interrupt priority before calling this method. You MUST NOT
/// do it after.
///
pub fn start(&'static self, irq: impl InterruptContext) -> crate::SendSpawner {
if self
.started
.compare_exchange(false, true, Ordering::Acquire, Ordering::Relaxed)
.is_err()
{
panic!("InterruptExecutor::start() called multiple times on the same executor.");
}
unsafe {
(&mut *self.executor.get())
.as_mut_ptr()
.write(raw::Executor::new(irq.context()))
}
let executor = unsafe { (&*self.executor.get()).assume_init_ref() };
irq.enable();
executor.spawner().make_send()
}
/// Get a SendSpawner for this executor
///
/// This returns a [`SendSpawner`] you can use to spawn tasks on this
/// executor.
///
/// This MUST only be called on an executor that has already been spawned.
/// The function will panic otherwise.
pub fn spawner(&'static self) -> crate::SendSpawner {
if !self.started.load(Ordering::Acquire) {
panic!("InterruptExecutor::spawner() called on uninitialized executor.");
}
let executor = unsafe { (&*self.executor.get()).assume_init_ref() };
executor.spawner().make_send()
}
}

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@ -37,11 +37,6 @@ pub use arch::*;
pub mod raw;
#[cfg(feature = "executor-interrupt")]
pub mod interrupt;
#[cfg(feature = "executor-interrupt")]
pub use interrupt::*;
mod spawner;
pub use spawner::*;

View File

@ -291,11 +291,6 @@ impl<F: Future + 'static, const N: usize> TaskPool<F, N> {
}
}
/// Context given to the thread-mode executor's pender.
#[repr(transparent)]
#[derive(Clone, Copy)]
pub struct PenderContext(*mut ());
/// Platform/architecture-specific action executed when an executor has pending work.
///
/// When a task within an executor is woken, the `Pender` is called. This does a
@ -306,15 +301,13 @@ pub struct PenderContext(*mut ());
///
/// Platform/architecture implementations must provide a function that can be referred to as:
///
/// ```rust
/// use embassy_executor::raw::PenderContext;
///
/// ```rust///
/// extern "Rust" {
/// fn __pender(context: PenderContext);
/// fn __pender(context: *mut ());
/// }
/// ```
#[derive(Clone, Copy)]
pub struct Pender(PenderContext);
pub struct Pender(*mut ());
unsafe impl Send for Pender {}
unsafe impl Sync for Pender {}
@ -322,7 +315,7 @@ unsafe impl Sync for Pender {}
impl Pender {
pub(crate) fn pend(self) {
extern "Rust" {
fn __pender(context: PenderContext);
fn __pender(context: *mut ());
}
unsafe { __pender(self.0) };
}
@ -484,7 +477,7 @@ impl Executor {
/// When the executor has work to do, it will call the [`Pender`].
///
/// See [`Executor`] docs for details on `Pender`.
pub fn new(context: PenderContext) -> Self {
pub fn new(context: *mut ()) -> Self {
Self {
inner: SyncExecutor::new(Pender(context)),
_not_sync: PhantomData,