Struct SpinLock 

pub struct SpinLock<T> {
    locked: AtomicBool,
    inner: UnsafeCell<T>,
}

A tiny spinlock for short critical sections.

This lock is suitable for uniprocessor or early boot stages where:

• Preemption is either disabled or non-existent.
• Critical sections are very short (no I/O, no blocking).

Guarantees

• Provides mutual exclusion for access to the protected value.
• Sync is implemented when T: Send, allowing shared references across threads (the lock enforces interior mutability).

Caveats

• Does not disable interrupts.
• Busy-waits with spin_loop, so keep critical sections small.

Fields

locked: AtomicBool

Lock state (false = unlocked, true = locked).

inner: UnsafeCell<T>

The protected value.

Implementations

impl<T> SpinLock<T>

pub const fn new(inner: T) -> Self

Create a new spinlock wrapping inner.

pub fn with_lock<R>(&self, f: impl FnOnce(&mut T) -> R) -> R

Execute f with exclusive access to the inner value.

Spins until the lock is acquired, then releases it after f returns.

Panics

Never panics by itself; panics in f will unwind through the critical section.

Trait Implementations

impl<T: Send> Sync for SpinLock<T>