pub type BackoffSpinlockGuard<'a, T> = MutexGuard<'a, RawSpinlock<Backoff>, T>;
Expand description
A RAII guard that frees the exponential backoff spinlock when it goes out of scope.
Allows access to the locked data through the core::ops::Deref
and core::ops::DerefMut
operations.
§Example
use spinning_top::{guard::BackoffSpinlockGuard, BackoffSpinlock};
let spinlock = BackoffSpinlock::new(Vec::new());
// begin a new scope
{
// lock the spinlock to create a `BackoffSpinlockGuard`
let mut guard: BackoffSpinlockGuard<_> = spinlock.lock();
// guard can be used like a `&mut Vec` since it implements `DerefMut`
guard.push(1);
guard.push(2);
assert_eq!(guard.len(), 2);
} // guard is dropped -> frees the spinlock again
// spinlock is unlocked again
assert!(spinlock.try_lock().is_some());
Aliased Type§
struct BackoffSpinlockGuard<'a, T> { /* private fields */ }
Implementations
Source§impl<'a, R, T> MutexGuard<'a, R, T>
impl<'a, R, T> MutexGuard<'a, R, T>
Sourcepub fn mutex(s: &MutexGuard<'a, R, T>) -> &'a Mutex<R, T>
pub fn mutex(s: &MutexGuard<'a, R, T>) -> &'a Mutex<R, T>
Returns a reference to the original Mutex
object.
Sourcepub fn map<U, F>(s: MutexGuard<'a, R, T>, f: F) -> MappedMutexGuard<'a, R, U>
pub fn map<U, F>(s: MutexGuard<'a, R, T>, f: F) -> MappedMutexGuard<'a, R, U>
Makes a new MappedMutexGuard
for a component of the locked data.
This operation cannot fail as the MutexGuard
passed
in already locked the mutex.
This is an associated function that needs to be
used as MutexGuard::map(...)
. A method would interfere with methods of
the same name on the contents of the locked data.
Sourcepub fn try_map<U, F>(
s: MutexGuard<'a, R, T>,
f: F,
) -> Result<MappedMutexGuard<'a, R, U>, MutexGuard<'a, R, T>>
pub fn try_map<U, F>( s: MutexGuard<'a, R, T>, f: F, ) -> Result<MappedMutexGuard<'a, R, U>, MutexGuard<'a, R, T>>
Attempts to make a new MappedMutexGuard
for a component of the
locked data. The original guard is returned if the closure returns None
.
This operation cannot fail as the MutexGuard
passed
in already locked the mutex.
This is an associated function that needs to be
used as MutexGuard::try_map(...)
. A method would interfere with methods of
the same name on the contents of the locked data.
Sourcepub fn unlocked<F, U>(s: &mut MutexGuard<'a, R, T>, f: F) -> Uwhere
F: FnOnce() -> U,
pub fn unlocked<F, U>(s: &mut MutexGuard<'a, R, T>, f: F) -> Uwhere
F: FnOnce() -> U,
Temporarily unlocks the mutex to execute the given function.
This is safe because &mut
guarantees that there exist no other
references to the data protected by the mutex.
Sourcepub fn leak(s: MutexGuard<'a, R, T>) -> &'a mut T
pub fn leak(s: MutexGuard<'a, R, T>) -> &'a mut T
Leaks the mutex guard and returns a mutable reference to the data protected by the mutex.
This will leave the Mutex
in a locked state.
Source§impl<'a, R, T> MutexGuard<'a, R, T>where
R: RawMutexFair + 'a,
T: 'a + ?Sized,
impl<'a, R, T> MutexGuard<'a, R, T>where
R: RawMutexFair + 'a,
T: 'a + ?Sized,
Sourcepub fn unlock_fair(s: MutexGuard<'a, R, T>)
pub fn unlock_fair(s: MutexGuard<'a, R, T>)
Unlocks the mutex using a fair unlock protocol.
By default, mutexes are unfair and allow the current thread to re-lock the mutex before another has the chance to acquire the lock, even if that thread has been blocked on the mutex for a long time. This is the default because it allows much higher throughput as it avoids forcing a context switch on every mutex unlock. This can result in one thread acquiring a mutex many more times than other threads.
However in some cases it can be beneficial to ensure fairness by forcing
the lock to pass on to a waiting thread if there is one. This is done by
using this method instead of dropping the MutexGuard
normally.
Sourcepub fn unlocked_fair<F, U>(s: &mut MutexGuard<'a, R, T>, f: F) -> Uwhere
F: FnOnce() -> U,
pub fn unlocked_fair<F, U>(s: &mut MutexGuard<'a, R, T>, f: F) -> Uwhere
F: FnOnce() -> U,
Temporarily unlocks the mutex to execute the given function.
The mutex is unlocked using a fair unlock protocol.
This is safe because &mut
guarantees that there exist no other
references to the data protected by the mutex.
Sourcepub fn bump(s: &mut MutexGuard<'a, R, T>)
pub fn bump(s: &mut MutexGuard<'a, R, T>)
Temporarily yields the mutex to a waiting thread if there is one.
This method is functionally equivalent to calling unlock_fair
followed
by lock
, however it can be much more efficient in the case where there
are no waiting threads.