diff --git a/src/doc/unstable-book/src/library-features/hint-core-should-pause.md b/src/doc/unstable-book/src/library-features/hint-core-should-pause.md deleted file mode 100644 index 05e057be493..00000000000 --- a/src/doc/unstable-book/src/library-features/hint-core-should-pause.md +++ /dev/null @@ -1,41 +0,0 @@ -# `hint_core_should_pause` - -The tracking issue for this feature is: [#41196] - -[#41196]: https://github.com/rust-lang/rust/issues/41196 - ------------------------- - -Many programs have spin loops like the following: - -```rust,no_run -use std::sync::atomic::{AtomicBool,Ordering}; - -fn spin_loop(value: &AtomicBool) { - loop { - if value.load(Ordering::Acquire) { - break; - } - } -} -``` - -These programs can be improved in performance like so: - -```rust,no_run -#![feature(hint_core_should_pause)] -use std::sync::atomic; -use std::sync::atomic::{AtomicBool,Ordering}; - -fn spin_loop(value: &AtomicBool) { - loop { - if value.load(Ordering::Acquire) { - break; - } - atomic::hint_core_should_pause(); - } -} -``` - -Further improvements could combine `hint_core_should_pause` with -exponential backoff or `std::thread::yield_now`. diff --git a/src/libcore/sync/atomic.rs b/src/libcore/sync/atomic.rs index b7cf6d778a2..8a261b8f077 100644 --- a/src/libcore/sync/atomic.rs +++ b/src/libcore/sync/atomic.rs @@ -103,9 +103,8 @@ use fmt; /// /// On some platforms this function may not do anything at all. #[inline] -#[unstable(feature = "hint_core_should_pause", issue = "41196")] -pub fn hint_core_should_pause() -{ +#[stable(feature = "spin_loop_hint", since = "1.24.0")] +pub fn spin_loop_hint() { #[cfg(any(target_arch = "x86", target_arch = "x86_64"))] unsafe { asm!("pause" ::: "memory" : "volatile");