Struct buddy_system_allocator::LockedFrameAllocator

pub struct LockedFrameAllocator(_);

A locked version of FrameAllocator

Usage

Create a locked frame allocator and add frames to it:

use buddy_system_allocator::*;
let mut frame = LockedFrameAllocator::new();
assert!(frame.lock().alloc(1).is_none());

frame.lock().add_frame(0, 3);
let num = frame.lock().alloc(1);
assert_eq!(num, Some(2));
let num = frame.lock().alloc(2);
assert_eq!(num, Some(0));

Implementations

impl LockedFrameAllocator

pub fn new() -> LockedFrameAllocator

Creates an empty heap

Methods from Deref<Target = Mutex<FrameAllocator>>

pub fn is_locked(&self) -> bool

Returns true if the lock is currently held.

Safety

This function provides no synchronization guarantees and so its result should be considered ‘out of date’ the instant it is called. Do not use it for synchronization purposes. However, it may be useful as a heuristic.

pub fn lock(&self) -> MutexGuard<'_, T>

Locks the Mutex and returns a guard that permits access to the inner data.

The returned value may be dereferenced for data access and the lock will be dropped when the guard falls out of scope.

let lock = spin::Mutex::new(0);
{
    let mut data = lock.lock();
    // The lock is now locked and the data can be accessed
    *data += 1;
    // The lock is implicitly dropped at the end of the scope
}

pub unsafe fn force_unlock(&self)

Force unlock this Mutex.

Safety

This is extremely unsafe if the lock is not held by the current thread. However, this can be useful in some instances for exposing the lock to FFI that doesn’t know how to deal with RAII.

pub fn try_lock(&self) -> Option<MutexGuard<'_, T>>

Try to lock this Mutex, returning a lock guard if successful.

Example

let lock = spin::Mutex::new(42);

let maybe_guard = lock.try_lock();
assert!(maybe_guard.is_some());

// `maybe_guard` is still held, so the second call fails
let maybe_guard2 = lock.try_lock();
assert!(maybe_guard2.is_none());

Trait Implementations

impl Deref for LockedFrameAllocator

type Target = Mutex<FrameAllocator>

The resulting type after dereferencing.

fn deref(&self) -> &Mutex<FrameAllocator>

Dereferences the value.