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refactor: swap to swap_and_compare

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This commit is contained in:
k-nasa 2020-03-19 18:41:00 +09:00
parent b1ec1ea930
commit 2b44c1be2e
1 changed files with 5 additions and 5 deletions
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10
src/sync/spin_lock.rs
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@ -31,7 +31,7 @@ use crossbeam_utils::Backoff;
/// ``` /// ```
#[derive(Debug)] #[derive(Debug)]
pub struct Spinlock<T> { pub struct Spinlock<T> {
flag: AtomicBool, locked: AtomicBool,
value: UnsafeCell<T>, value: UnsafeCell<T>,
} }
@ -42,7 +42,7 @@ impl<T> Spinlock<T> {
/// Returns a new spinlock initialized with `value`. /// Returns a new spinlock initialized with `value`.
pub const fn new(value: T) -> Spinlock<T> { pub const fn new(value: T) -> Spinlock<T> {
Spinlock { Spinlock {
flag: AtomicBool::new(false), locked: AtomicBool::new(false),
value: UnsafeCell::new(value), value: UnsafeCell::new(value),
} }
} }
@ -50,7 +50,7 @@ impl<T> Spinlock<T> {
/// Locks the spinlock. /// Locks the spinlock.
pub fn lock(&self) -> SpinlockGuard<'_, T> { pub fn lock(&self) -> SpinlockGuard<'_, T> {
let backoff = Backoff::new(); let backoff = Backoff::new();
while self.flag.swap(true, Ordering::Acquire) { while self.locked.compare_and_swap(false, true, Ordering::Acquire) {
backoff.snooze(); backoff.snooze();
} }
SpinlockGuard { parent: self } SpinlockGuard { parent: self }
@ -58,7 +58,7 @@ impl<T> Spinlock<T> {
/// Attempts to lock the spinlock. /// Attempts to lock the spinlock.
pub fn try_lock(&self) -> Option<SpinlockGuard<'_, T>> { pub fn try_lock(&self) -> Option<SpinlockGuard<'_, T>> {
if self.flag.swap(true, Ordering::Acquire) { if self.locked.swap(true, Ordering::Acquire) {
None None
} else { } else {
Some(SpinlockGuard { parent: self }) Some(SpinlockGuard { parent: self })
@ -77,7 +77,7 @@ unsafe impl<T: Sync> Sync for SpinlockGuard<'_, T> {}
impl<'a, T> Drop for SpinlockGuard<'a, T> { impl<'a, T> Drop for SpinlockGuard<'a, T> {
fn drop(&mut self) { fn drop(&mut self) {
self.parent.flag.store(false, Ordering::Release); self.parent.locked.store(false, Ordering::Release);
} }
} }