From 171cdb94c7906670723b0965ca66d72a2352ac73 Mon Sep 17 00:00:00 2001 From: Dario Nieuwenhuis Date: Fri, 24 Nov 2023 21:37:27 +0100 Subject: [PATCH] executor: add support for main/task macros in stable (allocates tasks in an arena) --- .github/ci/test.sh | 1 + embassy-executor/Cargo.toml | 2 +- embassy-executor/src/arch/cortex_m.rs | 1 - embassy-executor/src/arch/riscv32.rs | 1 - embassy-executor/src/arch/std.rs | 1 - embassy-executor/src/arch/wasm.rs | 1 - embassy-executor/src/arch/xtensa.rs | 1 - embassy-executor/src/lib.rs | 95 ++++++++++++++++++++++++++- embassy-macros/Cargo.toml | 3 +- embassy-macros/src/macros/task.rs | 9 +++ 10 files changed, 105 insertions(+), 10 deletions(-) diff --git a/.github/ci/test.sh b/.github/ci/test.sh index e48d6e65..dfc2b08c 100755 --- a/.github/ci/test.sh +++ b/.github/ci/test.sh @@ -15,6 +15,7 @@ export CARGO_NET_GIT_FETCH_WITH_CLI=true hashtime restore /ci/cache/filetime.json || true hashtime save /ci/cache/filetime.json +MIRIFLAGS=-Zmiri-ignore-leaks cargo miri test --manifest-path ./embassy-executor/Cargo.toml MIRIFLAGS=-Zmiri-ignore-leaks cargo miri test --manifest-path ./embassy-executor/Cargo.toml --features nightly cargo test --manifest-path ./embassy-sync/Cargo.toml diff --git a/embassy-executor/Cargo.toml b/embassy-executor/Cargo.toml index f0e85a2c..3ff8440c 100644 --- a/embassy-executor/Cargo.toml +++ b/embassy-executor/Cargo.toml @@ -43,7 +43,7 @@ executor-thread = [] executor-interrupt = [] # Enable nightly-only features -nightly = [] +nightly = ["embassy-macros/nightly"] turbowakers = [] diff --git a/embassy-executor/src/arch/cortex_m.rs b/embassy-executor/src/arch/cortex_m.rs index 55299c94..4a6d5857 100644 --- a/embassy-executor/src/arch/cortex_m.rs +++ b/embassy-executor/src/arch/cortex_m.rs @@ -51,7 +51,6 @@ mod thread { use core::arch::asm; use core::marker::PhantomData; - #[cfg(feature = "nightly")] pub use embassy_macros::main_cortex_m as main; use crate::{raw, Spawner}; diff --git a/embassy-executor/src/arch/riscv32.rs b/embassy-executor/src/arch/riscv32.rs index 6814e784..ca12c340 100644 --- a/embassy-executor/src/arch/riscv32.rs +++ b/embassy-executor/src/arch/riscv32.rs @@ -7,7 +7,6 @@ pub use thread::*; mod thread { use core::marker::PhantomData; - #[cfg(feature = "nightly")] pub use embassy_macros::main_riscv as main; use portable_atomic::{AtomicBool, Ordering}; diff --git a/embassy-executor/src/arch/std.rs b/embassy-executor/src/arch/std.rs index 5b2f7e2e..598bb050 100644 --- a/embassy-executor/src/arch/std.rs +++ b/embassy-executor/src/arch/std.rs @@ -8,7 +8,6 @@ mod thread { use std::marker::PhantomData; use std::sync::{Condvar, Mutex}; - #[cfg(feature = "nightly")] pub use embassy_macros::main_std as main; use crate::{raw, Spawner}; diff --git a/embassy-executor/src/arch/wasm.rs b/embassy-executor/src/arch/wasm.rs index 15aed867..3faa9257 100644 --- a/embassy-executor/src/arch/wasm.rs +++ b/embassy-executor/src/arch/wasm.rs @@ -8,7 +8,6 @@ mod thread { use core::marker::PhantomData; - #[cfg(feature = "nightly")] pub use embassy_macros::main_wasm as main; use js_sys::Promise; use wasm_bindgen::prelude::*; diff --git a/embassy-executor/src/arch/xtensa.rs b/embassy-executor/src/arch/xtensa.rs index d335594e..6ed9f9e7 100644 --- a/embassy-executor/src/arch/xtensa.rs +++ b/embassy-executor/src/arch/xtensa.rs @@ -8,7 +8,6 @@ mod thread { use core::marker::PhantomData; use core::sync::atomic::{AtomicBool, Ordering}; - #[cfg(feature = "nightly")] pub use embassy_macros::main_riscv as main; use crate::{raw, Spawner}; diff --git a/embassy-executor/src/lib.rs b/embassy-executor/src/lib.rs index 3b61b4ba..ac7dbb03 100644 --- a/embassy-executor/src/lib.rs +++ b/embassy-executor/src/lib.rs @@ -1,5 +1,5 @@ #![cfg_attr(not(any(feature = "arch-std", feature = "arch-wasm")), no_std)] -#![cfg_attr(all(feature = "nightly", feature = "arch-xtensa"), feature(asm_experimental_arch))] +#![cfg_attr(feature = "arch-xtensa", feature(asm_experimental_arch))] #![allow(clippy::new_without_default)] #![doc = include_str!("../README.md")] #![warn(missing_docs)] @@ -7,7 +7,6 @@ // This mod MUST go first, so that the others see its macros. pub(crate) mod fmt; -#[cfg(feature = "nightly")] pub use embassy_macros::task; macro_rules! check_at_most_one { @@ -44,4 +43,94 @@ pub use spawner::*; /// Implementation details for embassy macros. /// Do not use. Used for macros and HALs only. Not covered by semver guarantees. #[doc(hidden)] -pub mod _export {} +#[cfg(not(feature = "nightly"))] +pub mod _export { + use core::alloc::Layout; + use core::cell::{Cell, UnsafeCell}; + use core::future::Future; + use core::mem::MaybeUninit; + use core::ptr::null_mut; + + use critical_section::{CriticalSection, Mutex}; + + use crate::raw::TaskPool; + + struct Arena { + buf: UnsafeCell>, + ptr: Mutex>, + } + + unsafe impl Sync for Arena {} + unsafe impl Send for Arena {} + + impl Arena { + const fn new() -> Self { + Self { + buf: UnsafeCell::new(MaybeUninit::uninit()), + ptr: Mutex::new(Cell::new(null_mut())), + } + } + + fn alloc(&'static self, cs: CriticalSection) -> &'static mut MaybeUninit { + let layout = Layout::new::(); + + let start = self.buf.get().cast::(); + let end = unsafe { start.add(N) }; + + let mut ptr = self.ptr.borrow(cs).get(); + if ptr.is_null() { + ptr = self.buf.get().cast::(); + } + + let bytes_left = (end as usize) - (ptr as usize); + let align_offset = (ptr as usize).next_multiple_of(layout.align()) - (ptr as usize); + + if align_offset + layout.size() > bytes_left { + panic!("arena full"); + } + + let res = unsafe { ptr.add(align_offset) }; + let ptr = unsafe { ptr.add(align_offset + layout.size()) }; + + self.ptr.borrow(cs).set(ptr); + + unsafe { &mut *(res as *mut MaybeUninit) } + } + } + + const ARENA_SIZE: usize = 16 * 1024; + static ARENA: Arena = Arena::new(); + + pub struct TaskPoolRef { + // type-erased `&'static mut TaskPool` + // Needed because statics can't have generics. + ptr: Mutex>, + } + unsafe impl Sync for TaskPoolRef {} + unsafe impl Send for TaskPoolRef {} + + impl TaskPoolRef { + pub const fn new() -> Self { + Self { + ptr: Mutex::new(Cell::new(null_mut())), + } + } + + /// Get the pool for this ref, allocating it from the arena the first time. + /// + /// safety: for a given TaskPoolRef instance, must always call with the exact + /// same generic params. + pub unsafe fn get(&'static self) -> &'static TaskPool { + critical_section::with(|cs| { + let ptr = self.ptr.borrow(cs); + if ptr.get().is_null() { + let pool = ARENA.alloc::>(cs); + pool.write(TaskPool::new()); + ptr.set(pool as *mut _ as _); + } + + unsafe { &*(ptr.get() as *const _) } + }) + } + } +} diff --git a/embassy-macros/Cargo.toml b/embassy-macros/Cargo.toml index 4e94bf83..e13104cf 100644 --- a/embassy-macros/Cargo.toml +++ b/embassy-macros/Cargo.toml @@ -20,4 +20,5 @@ proc-macro2 = "1.0.29" [lib] proc-macro = true -[features] \ No newline at end of file +[features] +nightly = [] \ No newline at end of file diff --git a/embassy-macros/src/macros/task.rs b/embassy-macros/src/macros/task.rs index 1d30434e..5161e102 100644 --- a/embassy-macros/src/macros/task.rs +++ b/embassy-macros/src/macros/task.rs @@ -79,6 +79,7 @@ pub fn run(args: &[NestedMeta], f: syn::ItemFn) -> Result ::embassy_executor::SpawnToken { type Fut = impl ::core::future::Future + 'static; @@ -87,6 +88,14 @@ pub fn run(args: &[NestedMeta], f: syn::ItemFn) -> Result ::embassy_executor::SpawnToken { + const POOL_SIZE: usize = #pool_size; + static POOL: ::embassy_executor::_export::TaskPoolRef = ::embassy_executor::_export::TaskPoolRef::new(); + unsafe { POOL.get::<_, POOL_SIZE>()._spawn_async_fn(move || #task_inner_ident(#(#arg_names,)*)) } + } + }; task_outer.attrs.append(&mut task_inner.attrs.clone());