Struct slabmalloc_safe::ObjectPage8k

#[repr(C)]
pub struct ObjectPage8k { /* private fields */ }

Holds allocated data within 2 4-KiB pages.

Has a data-section where objects are allocated from and a small amount of meta-data in the form of a bitmap to track allocations at the end of the page.

Notes

An object of this type will be exactly 8 KiB. It is marked repr(C) because we rely on a well defined order of struct members (e.g., dealloc does a cast to find the bitfield).

Trait Implementations

impl AllocablePage for ObjectPage8k

fn clear_metadata(&mut self)

clears the metadata section of the page

fn first_fit(&self, layout: Layout) -> Option<(usize, usize)>

Tries to find a free block within data that satisfies alignment requirement.

fn allocate(&mut self, layout: Layout) -> *mut u8

Tries to allocate an object within this page.

In case the slab is full, returns a null ptr.

fn is_full(&self) -> bool

Checks if we can still allocate more objects of a given layout within the page.

fn is_empty(&self, relevant_bits: usize) -> bool

Checks if the page has currently no allocations.

fn deallocate( &self, ptr: NonNull<u8>, layout: Layout ) -> Result<(), &'static str>

Deallocates a memory object within this page.

const SIZE: usize = 8_192usize

The total size (in bytes) of the page.

const METADATA_SIZE: usize = 80usize

const HEAP_ID_OFFSET: usize = 8_112usize

fn bitfield(&self) -> &[AtomicU64; 8]

fn bitfield_mut(&mut self) -> &mut [AtomicU64; 8]