Crate irq_safety

Types for interrupt-safe operations, i.e., avoiding deadlock when sharing data between a regular thread context and an interrupt handler context.

Key types include:

• HeldInterrupts: a guard type that auto-reenables interrupts when dropped, only if they were originally enabled when the guard was created.
• [ MutexIrqSafe] and [RwLockIrqSafe]: spinlock wrappers that use [spin::Mutex] and [spin::RwLock`] internally to auto-disable interrupts for the duration of the lock being held.

Structs

• HeldInterrupts
  A guard type for withholding regular interrupts on the current CPU.
• MutexIrqSafe
  This type provides interrupt-safe MUTual EXclusion based on [spin::Mutex].
• MutexIrqSafeGuard
  A guard to which the protected data can be accessed
• RwLockIrqSafe
  A simple wrapper around a RwLock whose guards disable interrupts properly
• RwLockIrqSafeReadGuard
  A guard to which the protected data can be read
• RwLockIrqSafeWriteGuard
  A guard to which the protected data can be written

Functions

• disable_interrupts
  Unconditionally disables regular interrupts (IRQs), not NMIs or fast interrupts (FIQs on aarch64).
• enable_interrupts
  Unconditionally enables regular interrupts (IRQs), not NMIs or fast interrupts (FIQs on aarch64).
• hold_interrupts
  Prevents regular interrupts from occurring until the returned HeldInterrupts object is dropped.
• interrupts_enabled
  Returns whether regular interrupts are enabled on the current CPU.