| <!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Source of the Rust file `/root/.cargo/git/checkouts/tokio-377c595163f99a10/dfe252d/tokio/src/runtime/task/core.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>core.rs - source</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../../SourceCodePro-Semibold.ttf.woff2"><link rel="stylesheet" href="../../../../normalize.css"><link rel="stylesheet" href="../../../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" href="../../../../ayu.css" disabled><link rel="stylesheet" href="../../../../dark.css" disabled><link rel="stylesheet" href="../../../../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../../../../storage.js"></script><script defer src="../../../../source-script.js"></script><script defer src="../../../../source-files.js"></script><script defer src="../../../../main.js"></script><noscript><link rel="stylesheet" href="../../../../noscript.css"></noscript><link rel="alternate icon" type="image/png" href="../../../../favicon-16x16.png"><link rel="alternate icon" type="image/png" href="../../../../favicon-32x32.png"><link rel="icon" type="image/svg+xml" href="../../../../favicon.svg"></head><body class="rustdoc source"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><a class="sidebar-logo" href="../../../../tokio/index.html"><div class="logo-container"><img class="rust-logo" src="../../../../rust-logo.svg" alt="logo"></div></a></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../../../tokio/index.html"><img class="rust-logo" src="../../../../rust-logo.svg" alt="logo"></a><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../../../../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../../../wheel.svg"></a></div></div></form></nav><section id="main-content" class="content"><div class="example-wrap"><pre class="src-line-numbers"><span id="1">1</span> |
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| </pre><pre class="rust"><code><span class="doccomment">//! Core task module. |
| //! |
| //! # Safety |
| //! |
| //! The functions in this module are private to the `task` module. All of them |
| //! should be considered `unsafe` to use, but are not marked as such since it |
| //! would be too noisy. |
| //! |
| //! Make sure to consult the relevant safety section of each function before |
| //! use. |
| |
| </span><span class="kw">use </span><span class="kw">crate</span>::future::Future; |
| <span class="kw">use </span><span class="kw">crate</span>::loom::cell::UnsafeCell; |
| <span class="kw">use </span><span class="kw">crate</span>::runtime::context; |
| <span class="kw">use </span><span class="kw">crate</span>::runtime::task::raw::{<span class="self">self</span>, Vtable}; |
| <span class="kw">use </span><span class="kw">crate</span>::runtime::task::state::State; |
| <span class="kw">use </span><span class="kw">crate</span>::runtime::task::{Id, Schedule}; |
| <span class="kw">use </span><span class="kw">crate</span>::util::linked_list; |
| |
| <span class="kw">use </span>std::pin::Pin; |
| <span class="kw">use </span>std::ptr::NonNull; |
| <span class="kw">use </span>std::task::{Context, Poll, Waker}; |
| |
| <span class="doccomment">/// The task cell. Contains the components of the task. |
| /// |
| /// It is critical for `Header` to be the first field as the task structure will |
| /// be referenced by both *mut Cell and *mut Header. |
| /// |
| /// Any changes to the layout of this struct _must_ also be reflected in the |
| /// const fns in raw.rs. |
| </span><span class="attribute">#[repr(C)] |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">struct </span>Cell<T: Future, S> { |
| <span class="doccomment">/// Hot task state data |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) header: Header, |
| |
| <span class="doccomment">/// Either the future or output, depending on the execution stage. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) core: Core<T, S>, |
| |
| <span class="doccomment">/// Cold data |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) trailer: Trailer, |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">struct </span>CoreStage<T: Future> { |
| stage: UnsafeCell<Stage<T>>, |
| } |
| |
| <span class="doccomment">/// The core of the task. |
| /// |
| /// Holds the future or output, depending on the stage of execution. |
| /// |
| /// Any changes to the layout of this struct _must_ also be reflected in the |
| /// const fns in raw.rs. |
| </span><span class="attribute">#[repr(C)] |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">struct </span>Core<T: Future, S> { |
| <span class="doccomment">/// Scheduler used to drive this future. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) scheduler: S, |
| |
| <span class="doccomment">/// The task's ID, used for populating `JoinError`s. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) task_id: Id, |
| |
| <span class="doccomment">/// Either the future or the output. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) stage: CoreStage<T>, |
| } |
| |
| <span class="doccomment">/// Crate public as this is also needed by the pool. |
| </span><span class="attribute">#[repr(C)] |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">struct </span>Header { |
| <span class="doccomment">/// Task state. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) state: State, |
| |
| <span class="doccomment">/// Pointer to next task, used with the injection queue. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) queue_next: UnsafeCell<<span class="prelude-ty">Option</span><NonNull<Header>>>, |
| |
| <span class="doccomment">/// Table of function pointers for executing actions on the task. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) vtable: <span class="kw-2">&</span><span class="lifetime">'static </span>Vtable, |
| |
| <span class="doccomment">/// This integer contains the id of the OwnedTasks or LocalOwnedTasks that |
| /// this task is stored in. If the task is not in any list, should be the |
| /// id of the list that it was previously in, or zero if it has never been |
| /// in any list. |
| /// |
| /// Once a task has been bound to a list, it can never be bound to another |
| /// list, even if removed from the first list. |
| /// |
| /// The id is not unset when removed from a list because we want to be able |
| /// to read the id without synchronization, even if it is concurrently being |
| /// removed from the list. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) owner_id: UnsafeCell<u64>, |
| |
| <span class="doccomment">/// The tracing ID for this instrumented task. |
| </span><span class="attribute">#[cfg(all(tokio_unstable, feature = <span class="string">"tracing"</span>))] |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) tracing_id: <span class="prelude-ty">Option</span><tracing::Id>, |
| } |
| |
| <span class="kw">unsafe impl </span>Send <span class="kw">for </span>Header {} |
| <span class="kw">unsafe impl </span>Sync <span class="kw">for </span>Header {} |
| |
| <span class="doccomment">/// Cold data is stored after the future. Data is considered cold if it is only |
| /// used during creation or shutdown of the task. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">struct </span>Trailer { |
| <span class="doccomment">/// Pointers for the linked list in the `OwnedTasks` that owns this task. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) owned: linked_list::Pointers<Header>, |
| <span class="doccomment">/// Consumer task waiting on completion of this task. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) waker: UnsafeCell<<span class="prelude-ty">Option</span><Waker>>, |
| } |
| |
| <span class="macro">generate_addr_of_methods! </span>{ |
| <span class="kw">impl</span><> Trailer { |
| <span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">unsafe fn </span>addr_of_owned(<span class="self">self</span>: NonNull<<span class="self">Self</span>>) -> NonNull<linked_list::Pointers<Header>> { |
| <span class="kw-2">&</span><span class="self">self</span>.owned |
| } |
| } |
| } |
| |
| <span class="doccomment">/// Either the future or the output. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">enum </span>Stage<T: Future> { |
| Running(T), |
| Finished(<span class="kw">super</span>::Result<T::Output>), |
| Consumed, |
| } |
| |
| <span class="kw">impl</span><T: Future, S: Schedule> Cell<T, S> { |
| <span class="doccomment">/// Allocates a new task cell, containing the header, trailer, and core |
| /// structures. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">fn </span>new(future: T, scheduler: S, state: State, task_id: Id) -> Box<Cell<T, S>> { |
| <span class="attribute">#[cfg(all(tokio_unstable, feature = <span class="string">"tracing"</span>))] |
| </span><span class="kw">let </span>tracing_id = future.id(); |
| <span class="kw">let </span>result = Box::new(Cell { |
| header: Header { |
| state, |
| queue_next: UnsafeCell::new(<span class="prelude-val">None</span>), |
| vtable: raw::vtable::<T, S>(), |
| owner_id: UnsafeCell::new(<span class="number">0</span>), |
| <span class="attribute">#[cfg(all(tokio_unstable, feature = <span class="string">"tracing"</span>))] |
| </span>tracing_id, |
| }, |
| core: Core { |
| scheduler, |
| stage: CoreStage { |
| stage: UnsafeCell::new(Stage::Running(future)), |
| }, |
| task_id, |
| }, |
| trailer: Trailer { |
| waker: UnsafeCell::new(<span class="prelude-val">None</span>), |
| owned: linked_list::Pointers::new(), |
| }, |
| }); |
| |
| <span class="attribute">#[cfg(debug_assertions)] |
| </span>{ |
| <span class="kw">let </span>trailer_addr = (<span class="kw-2">&</span>result.trailer) <span class="kw">as </span><span class="kw-2">*const </span>Trailer <span class="kw">as </span>usize; |
| <span class="kw">let </span>trailer_ptr = <span class="kw">unsafe </span>{ Header::get_trailer(NonNull::from(<span class="kw-2">&</span>result.header)) }; |
| <span class="macro">assert_eq!</span>(trailer_addr, trailer_ptr.as_ptr() <span class="kw">as </span>usize); |
| |
| <span class="kw">let </span>scheduler_addr = (<span class="kw-2">&</span>result.core.scheduler) <span class="kw">as </span><span class="kw-2">*const </span>S <span class="kw">as </span>usize; |
| <span class="kw">let </span>scheduler_ptr = |
| <span class="kw">unsafe </span>{ Header::get_scheduler::<S>(NonNull::from(<span class="kw-2">&</span>result.header)) }; |
| <span class="macro">assert_eq!</span>(scheduler_addr, scheduler_ptr.as_ptr() <span class="kw">as </span>usize); |
| |
| <span class="kw">let </span>id_addr = (<span class="kw-2">&</span>result.core.task_id) <span class="kw">as </span><span class="kw-2">*const </span>Id <span class="kw">as </span>usize; |
| <span class="kw">let </span>id_ptr = <span class="kw">unsafe </span>{ Header::get_id_ptr(NonNull::from(<span class="kw-2">&</span>result.header)) }; |
| <span class="macro">assert_eq!</span>(id_addr, id_ptr.as_ptr() <span class="kw">as </span>usize); |
| } |
| |
| result |
| } |
| } |
| |
| <span class="kw">impl</span><T: Future> CoreStage<T> { |
| <span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">fn </span>with_mut<R>(<span class="kw-2">&</span><span class="self">self</span>, f: <span class="kw">impl </span>FnOnce(<span class="kw-2">*mut </span>Stage<T>) -> R) -> R { |
| <span class="self">self</span>.stage.with_mut(f) |
| } |
| } |
| |
| <span class="doccomment">/// Set and clear the task id in the context when the future is executed or |
| /// dropped, or when the output produced by the future is dropped. |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">struct </span>TaskIdGuard { |
| parent_task_id: <span class="prelude-ty">Option</span><Id>, |
| } |
| |
| <span class="kw">impl </span>TaskIdGuard { |
| <span class="kw">fn </span>enter(id: Id) -> <span class="self">Self </span>{ |
| TaskIdGuard { |
| parent_task_id: context::set_current_task_id(<span class="prelude-val">Some</span>(id)), |
| } |
| } |
| } |
| |
| <span class="kw">impl </span>Drop <span class="kw">for </span>TaskIdGuard { |
| <span class="kw">fn </span>drop(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| context::set_current_task_id(<span class="self">self</span>.parent_task_id); |
| } |
| } |
| |
| <span class="kw">impl</span><T: Future, S: Schedule> Core<T, S> { |
| <span class="doccomment">/// Polls the future. |
| /// |
| /// # Safety |
| /// |
| /// The caller must ensure it is safe to mutate the `state` field. This |
| /// requires ensuring mutual exclusion between any concurrent thread that |
| /// might modify the future or output field. |
| /// |
| /// The mutual exclusion is implemented by `Harness` and the `Lifecycle` |
| /// component of the task state. |
| /// |
| /// `self` must also be pinned. This is handled by storing the task on the |
| /// heap. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">fn </span>poll(<span class="kw-2">&</span><span class="self">self</span>, <span class="kw-2">mut </span>cx: Context<<span class="lifetime">'_</span>>) -> Poll<T::Output> { |
| <span class="kw">let </span>res = { |
| <span class="self">self</span>.stage.stage.with_mut(|ptr| { |
| <span class="comment">// Safety: The caller ensures mutual exclusion to the field. |
| </span><span class="kw">let </span>future = <span class="kw">match unsafe </span>{ <span class="kw-2">&mut *</span>ptr } { |
| Stage::Running(future) => future, |
| <span class="kw">_ </span>=> <span class="macro">unreachable!</span>(<span class="string">"unexpected stage"</span>), |
| }; |
| |
| <span class="comment">// Safety: The caller ensures the future is pinned. |
| </span><span class="kw">let </span>future = <span class="kw">unsafe </span>{ Pin::new_unchecked(future) }; |
| |
| <span class="kw">let </span>_guard = TaskIdGuard::enter(<span class="self">self</span>.task_id); |
| future.poll(<span class="kw-2">&mut </span>cx) |
| }) |
| }; |
| |
| <span class="kw">if </span>res.is_ready() { |
| <span class="self">self</span>.drop_future_or_output(); |
| } |
| |
| res |
| } |
| |
| <span class="doccomment">/// Drops the future. |
| /// |
| /// # Safety |
| /// |
| /// The caller must ensure it is safe to mutate the `stage` field. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">fn </span>drop_future_or_output(<span class="kw-2">&</span><span class="self">self</span>) { |
| <span class="comment">// Safety: the caller ensures mutual exclusion to the field. |
| </span><span class="kw">unsafe </span>{ |
| <span class="self">self</span>.set_stage(Stage::Consumed); |
| } |
| } |
| |
| <span class="doccomment">/// Stores the task output. |
| /// |
| /// # Safety |
| /// |
| /// The caller must ensure it is safe to mutate the `stage` field. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">fn </span>store_output(<span class="kw-2">&</span><span class="self">self</span>, output: <span class="kw">super</span>::Result<T::Output>) { |
| <span class="comment">// Safety: the caller ensures mutual exclusion to the field. |
| </span><span class="kw">unsafe </span>{ |
| <span class="self">self</span>.set_stage(Stage::Finished(output)); |
| } |
| } |
| |
| <span class="doccomment">/// Takes the task output. |
| /// |
| /// # Safety |
| /// |
| /// The caller must ensure it is safe to mutate the `stage` field. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">fn </span>take_output(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="kw">super</span>::Result<T::Output> { |
| <span class="kw">use </span>std::mem; |
| |
| <span class="self">self</span>.stage.stage.with_mut(|ptr| { |
| <span class="comment">// Safety:: the caller ensures mutual exclusion to the field. |
| </span><span class="kw">match </span>mem::replace(<span class="kw">unsafe </span>{ <span class="kw-2">&mut *</span>ptr }, Stage::Consumed) { |
| Stage::Finished(output) => output, |
| <span class="kw">_ </span>=> <span class="macro">panic!</span>(<span class="string">"JoinHandle polled after completion"</span>), |
| } |
| }) |
| } |
| |
| <span class="kw">unsafe fn </span>set_stage(<span class="kw-2">&</span><span class="self">self</span>, stage: Stage<T>) { |
| <span class="kw">let </span>_guard = TaskIdGuard::enter(<span class="self">self</span>.task_id); |
| <span class="self">self</span>.stage.stage.with_mut(|ptr| <span class="kw-2">*</span>ptr = stage) |
| } |
| } |
| |
| <span class="macro">cfg_rt_multi_thread! </span>{ |
| <span class="kw">impl </span>Header { |
| <span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">unsafe fn </span>set_next(<span class="kw-2">&</span><span class="self">self</span>, next: <span class="prelude-ty">Option</span><NonNull<Header>>) { |
| <span class="self">self</span>.queue_next.with_mut(|ptr| <span class="kw-2">*</span>ptr = next); |
| } |
| } |
| } |
| |
| <span class="kw">impl </span>Header { |
| <span class="comment">// safety: The caller must guarantee exclusive access to this field, and |
| // must ensure that the id is either 0 or the id of the OwnedTasks |
| // containing this task. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">unsafe fn </span>set_owner_id(<span class="kw-2">&</span><span class="self">self</span>, owner: u64) { |
| <span class="self">self</span>.owner_id.with_mut(|ptr| <span class="kw-2">*</span>ptr = owner); |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">fn </span>get_owner_id(<span class="kw-2">&</span><span class="self">self</span>) -> u64 { |
| <span class="comment">// safety: If there are concurrent writes, then that write has violated |
| // the safety requirements on `set_owner_id`. |
| </span><span class="kw">unsafe </span>{ <span class="self">self</span>.owner_id.with(|ptr| <span class="kw-2">*</span>ptr) } |
| } |
| |
| <span class="doccomment">/// Gets a pointer to the `Trailer` of the task containing this `Header`. |
| /// |
| /// # Safety |
| /// |
| /// The provided raw pointer must point at the header of a task. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">unsafe fn </span>get_trailer(me: NonNull<Header>) -> NonNull<Trailer> { |
| <span class="kw">let </span>offset = me.as_ref().vtable.trailer_offset; |
| <span class="kw">let </span>trailer = me.as_ptr().cast::<u8>().add(offset).cast::<Trailer>(); |
| NonNull::new_unchecked(trailer) |
| } |
| |
| <span class="doccomment">/// Gets a pointer to the scheduler of the task containing this `Header`. |
| /// |
| /// # Safety |
| /// |
| /// The provided raw pointer must point at the header of a task. |
| /// |
| /// The generic type S must be set to the correct scheduler type for this |
| /// task. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">unsafe fn </span>get_scheduler<S>(me: NonNull<Header>) -> NonNull<S> { |
| <span class="kw">let </span>offset = me.as_ref().vtable.scheduler_offset; |
| <span class="kw">let </span>scheduler = me.as_ptr().cast::<u8>().add(offset).cast::<S>(); |
| NonNull::new_unchecked(scheduler) |
| } |
| |
| <span class="doccomment">/// Gets a pointer to the id of the task containing this `Header`. |
| /// |
| /// # Safety |
| /// |
| /// The provided raw pointer must point at the header of a task. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">unsafe fn </span>get_id_ptr(me: NonNull<Header>) -> NonNull<Id> { |
| <span class="kw">let </span>offset = me.as_ref().vtable.id_offset; |
| <span class="kw">let </span>id = me.as_ptr().cast::<u8>().add(offset).cast::<Id>(); |
| NonNull::new_unchecked(id) |
| } |
| |
| <span class="doccomment">/// Gets the id of the task containing this `Header`. |
| /// |
| /// # Safety |
| /// |
| /// The provided raw pointer must point at the header of a task. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">unsafe fn </span>get_id(me: NonNull<Header>) -> Id { |
| <span class="kw">let </span>ptr = Header::get_id_ptr(me).as_ptr(); |
| <span class="kw-2">*</span>ptr |
| } |
| |
| <span class="doccomment">/// Gets the tracing id of the task containing this `Header`. |
| /// |
| /// # Safety |
| /// |
| /// The provided raw pointer must point at the header of a task. |
| </span><span class="attribute">#[cfg(all(tokio_unstable, feature = <span class="string">"tracing"</span>))] |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">unsafe fn </span>get_tracing_id(me: <span class="kw-2">&</span>NonNull<Header>) -> <span class="prelude-ty">Option</span><<span class="kw-2">&</span>tracing::Id> { |
| me.as_ref().tracing_id.as_ref() |
| } |
| } |
| |
| <span class="kw">impl </span>Trailer { |
| <span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">unsafe fn </span>set_waker(<span class="kw-2">&</span><span class="self">self</span>, waker: <span class="prelude-ty">Option</span><Waker>) { |
| <span class="self">self</span>.waker.with_mut(|ptr| { |
| <span class="kw-2">*</span>ptr = waker; |
| }); |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">unsafe fn </span>will_wake(<span class="kw-2">&</span><span class="self">self</span>, waker: <span class="kw-2">&</span>Waker) -> bool { |
| <span class="self">self</span>.waker |
| .with(|ptr| (<span class="kw-2">*</span>ptr).as_ref().unwrap().will_wake(waker)) |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">fn </span>wake_join(<span class="kw-2">&</span><span class="self">self</span>) { |
| <span class="self">self</span>.waker.with(|ptr| <span class="kw">match unsafe </span>{ <span class="kw-2">&*</span>ptr } { |
| <span class="prelude-val">Some</span>(waker) => waker.wake_by_ref(), |
| <span class="prelude-val">None </span>=> <span class="macro">panic!</span>(<span class="string">"waker missing"</span>), |
| }); |
| } |
| } |
| |
| <span class="attribute">#[test] |
| #[cfg(not(loom))] |
| </span><span class="kw">fn </span>header_lte_cache_line() { |
| <span class="kw">use </span>std::mem::size_of; |
| |
| <span class="macro">assert!</span>(size_of::<Header>() <= <span class="number">8 </span>* size_of::<<span class="kw-2">*const </span>()>()); |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../../../" data-current-crate="tokio" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |