diff --git a/tokio/src/loom/std/atomic_u16.rs b/tokio/src/loom/std/atomic_u16.rs index 70390972b4b..c1c531208c2 100644 --- a/tokio/src/loom/std/atomic_u16.rs +++ b/tokio/src/loom/std/atomic_u16.rs @@ -11,7 +11,7 @@ unsafe impl Send for AtomicU16 {} unsafe impl Sync for AtomicU16 {} impl AtomicU16 { - pub(crate) fn new(val: u16) -> AtomicU16 { + pub(crate) const fn new(val: u16) -> AtomicU16 { let inner = UnsafeCell::new(std::sync::atomic::AtomicU16::new(val)); AtomicU16 { inner } } diff --git a/tokio/src/loom/std/atomic_u32.rs b/tokio/src/loom/std/atomic_u32.rs index 6f786c519f1..61f95fb30ce 100644 --- a/tokio/src/loom/std/atomic_u32.rs +++ b/tokio/src/loom/std/atomic_u32.rs @@ -11,7 +11,7 @@ unsafe impl Send for AtomicU32 {} unsafe impl Sync for AtomicU32 {} impl AtomicU32 { - pub(crate) fn new(val: u32) -> AtomicU32 { + pub(crate) const fn new(val: u32) -> AtomicU32 { let inner = UnsafeCell::new(std::sync::atomic::AtomicU32::new(val)); AtomicU32 { inner } } diff --git a/tokio/src/loom/std/atomic_u8.rs b/tokio/src/loom/std/atomic_u8.rs index 4fcd0df3d45..408aea338c6 100644 --- a/tokio/src/loom/std/atomic_u8.rs +++ b/tokio/src/loom/std/atomic_u8.rs @@ -11,7 +11,7 @@ unsafe impl Send for AtomicU8 {} unsafe impl Sync for AtomicU8 {} impl AtomicU8 { - pub(crate) fn new(val: u8) -> AtomicU8 { + pub(crate) const fn new(val: u8) -> AtomicU8 { let inner = UnsafeCell::new(std::sync::atomic::AtomicU8::new(val)); AtomicU8 { inner } } diff --git a/tokio/src/loom/std/unsafe_cell.rs b/tokio/src/loom/std/unsafe_cell.rs index f2b03d8dc2a..66c1d7943e0 100644 --- a/tokio/src/loom/std/unsafe_cell.rs +++ b/tokio/src/loom/std/unsafe_cell.rs @@ -2,7 +2,7 @@ pub(crate) struct UnsafeCell(std::cell::UnsafeCell); impl UnsafeCell { - pub(crate) fn new(data: T) -> UnsafeCell { + pub(crate) const fn new(data: T) -> UnsafeCell { UnsafeCell(std::cell::UnsafeCell::new(data)) } diff --git a/tokio/src/sync/notify.rs b/tokio/src/sync/notify.rs index 74c69e50cb8..c69e2b07dbf 100644 --- a/tokio/src/sync/notify.rs +++ b/tokio/src/sync/notify.rs @@ -170,6 +170,24 @@ impl Notify { } } + /// Create a new `Notify`, initialized without a permit. + /// + /// # Examples + /// + /// ``` + /// use tokio::sync::Notify; + /// + /// static NOTIFY: Notify = Notify::const_new(); + /// ``` + #[cfg(all(feature = "parking_lot", not(all(loom, test))))] + #[cfg_attr(docsrs, doc(cfg(feature = "parking_lot")))] + pub const fn const_new() -> Notify { + Notify { + state: AtomicU8::new(0), + waiters: Mutex::const_new(LinkedList::new()), + } + } + /// Wait for a notification. /// /// Equivalent to: diff --git a/tokio/src/sync/rwlock.rs b/tokio/src/sync/rwlock.rs index 650a7cf607a..840889bace8 100644 --- a/tokio/src/sync/rwlock.rs +++ b/tokio/src/sync/rwlock.rs @@ -485,6 +485,27 @@ impl RwLock { } } + /// Creates a new instance of an `RwLock` which is unlocked. + /// + /// # Examples + /// + /// ``` + /// use tokio::sync::RwLock; + /// + /// static LOCK: RwLock = RwLock::const_new(5); + /// ``` + #[cfg(all(feature = "parking_lot", not(all(loom, test))))] + #[cfg_attr(docsrs, doc(cfg(feature = "parking_lot")))] + pub const fn const_new(value: T) -> RwLock + where + T: Sized, + { + RwLock { + c: UnsafeCell::new(value), + s: Semaphore::const_new(MAX_READS), + } + } + /// Locks this rwlock with shared read access, causing the current task /// to yield until the lock has been acquired. /// diff --git a/tokio/src/sync/semaphore.rs b/tokio/src/sync/semaphore.rs index 2489d34aaaf..136f14e62f9 100644 --- a/tokio/src/sync/semaphore.rs +++ b/tokio/src/sync/semaphore.rs @@ -74,6 +74,15 @@ impl Semaphore { } } + /// Creates a new semaphore with the initial number of permits. + #[cfg(all(feature = "parking_lot", not(all(loom, test))))] + #[cfg_attr(docsrs, doc(cfg(feature = "parking_lot")))] + pub const fn const_new(permits: usize) -> Self { + Self { + ll_sem: ll::Semaphore::const_new(permits), + } + } + /// Returns the current number of available permits. pub fn available_permits(&self) -> usize { self.ll_sem.available_permits()