Data Structures
struct	qnode

Macros
#define	queue_free(q) queue_destroy((q), free)

Typedefs
typedef struct qnode	qnode_t

typedef qnode_t	q_t

Functions
q_t *	queue_init (void)

void	queue_destroy (q_t q, void(callback)(void *))

qnode_t *	enqueue (q_t q, void data)

qnode_t *	prequeue (q_t q, void data)

qnode_t *	queue_move_to_tail (q_t q, qnode_t node)
	Move existing node to tail (MRU) without reallocation. More...

qnode_t *	queue_move_to_tail_of (q_t from_q, q_t to_q, qnode_t *node)
	Move node from one queue to another without memory reallocation. More...

void *	dequeue (q_t *q)

Macro Definition Documentation

◆ queue_free

#define queue_free ( q ) queue_destroy((q), free)

Typedef Documentation

◆ q_t

typedef qnode_t q_t

◆ qnode_t

typedef struct qnode qnode_t

Function Documentation

◆ dequeue()

void * dequeue ( q_t * q )

Take from head

◆ enqueue()

qnode_t * enqueue	(	q_t *	q,
		void *	data
	)

Insert at tail

◆ prequeue()

qnode_t * prequeue	(	q_t *	q,
		void *	data
	)

Insert at head

◆ queue_destroy()

void queue_destroy	(	q_t *	q,
		void()(void )	callback
	)

◆ queue_init()

q_t * queue_init ( void )

◆ queue_move_to_tail()

qnode_t * queue_move_to_tail	(	q_t *	q,
		qnode_t *	node
	)

Move existing node to tail (MRU) without reallocation.

This function provides O(1) move-to-tail operation without malloc/free overhead. Used by ARC cache to efficiently update T2 on cache hits.

Parameters

[in]	q	Queue (circular doubly-linked list with sentinel)
[in]	node	Node to move to tail (must currently be in queue q)

Returns: The same node pointer (now at tail/MRU), or NULL on error

Note: The node pointer remains valid and unchanged - only its position changes; If node is already at tail, this is a no-op (fast path); This is thread-safe if external locking is used (same as other queue ops)

◆ queue_move_to_tail_of()

qnode_t * queue_move_to_tail_of	(	q_t *	from_q,
		q_t *	to_q,
		qnode_t *	node
	)

Move node from one queue to another without memory reallocation.

Removes node from source queue and adds it to tail of destination queue. The node pointer remains valid and unchanged - enables zero-allocation transitions between ARC lists (T1→T2, T1→B1, T2→B2, B1→T2, B2→T2).