Struct Arena 

pub struct Arena<K, V, const N: usize> { /* private fields */ }

A lock-free static memory pool for Nodes using tagged indices to prevent ABA.

Implementations

impl<K, V, const N: usize> Arena<K, V, N>

pub const fn new() -> Self

pub fn alloc( &self, key: K, value: V, node: *mut ThreadStateNode, ) -> Option<usize>

Allocates a node from the free list and initializes it. Returns the index of the allocated node.

Safety

node must be a valid pointer.

pub unsafe fn free(&self, index: usize)

Safely frees a node, running its drop logic, and returning it to the free list. MUST only be called when no threads are reading the node (e.g., via QSBR).

pub unsafe fn drop_node(&self, index: usize)

Drops the inner item without pushing it to the free list.

pub fn set_next_free(&self, index: u32, next: u32)

pub unsafe fn free_batch(&self, head_idx: u32, tail_idx: u32)

Pushes a batch of nodes to the global free list without dropping it.

pub unsafe fn free_raw(&self, index: usize)

Pushes a node index to the global free list without dropping it.

pub unsafe fn get(&self, index: usize) -> &Node<K, V>

Get a reference to a node. Caller must ensure index is valid and the node is currently allocated.

pub unsafe fn get_mut(&self, index: usize) -> &mut Node<K, V>

Trait Implementations

impl<K, V, const N: usize> Default for Arena<K, V, N>

fn default() -> Self

Returns the “default value” for a type.

impl<K: Send, V: Send, const N: usize> Send for Arena<K, V, N>

impl<K: Sync, V: Sync, const N: usize> Sync for Arena<K, V, N>