Struct tokio::util::sharded_list::ShardedList

pub(crate) struct ShardedList<L, T> {
    lists: Box<[Mutex<LinkedList<L, T>>]>,
    added: MetricAtomicU64,
    count: MetricAtomicUsize,
    shard_mask: usize,
}

An intrusive linked list supporting highly concurrent updates.

It currently relies on LinkedList, so it is the caller’s responsibility to ensure the list is empty before dropping it.

Note: Due to its inner sharded design, the order of nodes cannot be guaranteed.

Fields

lists: Box<[Mutex<LinkedList<L, T>>]>

added: MetricAtomicU64

count: MetricAtomicUsize

shard_mask: usize

Implementations

impl<L, T> ShardedList<L, T>

pub(crate) fn new(sharded_size: usize) -> Self

Creates a new and empty sharded linked list with the specified size.

impl<L: ShardedListItem> ShardedList<L, L::Target>

pub(crate) fn pop_back(&self, shard_id: usize) -> Option<L::Handle>

Removes the last element from a list specified by shard_id and returns it, or None if it is empty.

pub(crate) unsafe fn remove( &self, node: NonNull<L::Target>, ) -> Option<L::Handle>

Removes the specified node from the list.

Safety

The caller must ensure that exactly one of the following is true:

• node is currently contained by self,
• node is not contained by any list,
• node is currently contained by some other GuardedLinkedList.

pub(crate) fn lock_shard(&self, val: &L::Handle) -> ShardGuard<'_, L, L::Target>

Gets the lock of ShardedList, makes us have the write permission.

pub(crate) fn len(&self) -> usize

Gets the count of elements in this list.

pub(crate) fn added(&self) -> u64

Gets the total number of elements added to this list.

pub(crate) fn is_empty(&self) -> bool

Returns whether the linked list does not contain any node.

pub(crate) fn shard_size(&self) -> usize

Gets the shard size of this SharedList.

Used to help us to decide the parameter shard_id of the pop_back method.

fn shard_inner( &self, id: usize, ) -> MutexGuard<'_, LinkedList<L, <L as Link>::Target>>