*
* For convenience, cds_wfcq_dequeue_blocking() and
* cds_wfcq_splice_blocking() hold the dequeue lock.
+ *
+ * Besides locking, mutual exclusion of dequeue, splice and iteration
+ * can be ensured by performing all of those operations from a single
+ * thread, without requiring any lock.
*/
#define WFCQ_ADAPT_ATTEMPTS 10 /* Retry if being set */
*
* Content written into the node before enqueue is guaranteed to be
* consistent, but no other memory ordering is ensured.
- * Should be called with cds_wfcq_dequeue_lock() held.
+ * Dequeue/splice/iteration mutual exclusion should be ensured by the
+ * caller.
*
* Used by for-like iteration macros in urcu/wfqueue.h:
* __cds_wfcq_for_each_blocking()
*
* Content written into the node before enqueue is guaranteed to be
* consistent, but no other memory ordering is ensured.
- * Should be called with cds_wfcq_dequeue_lock() held.
+ * Dequeue/splice/iteration mutual exclusion should be ensured by the
+ * caller.
*
* Used by for-like iteration macros in urcu/wfqueue.h:
* __cds_wfcq_for_each_blocking()
* Content written into the node before enqueue is guaranteed to be
* consistent, but no other memory ordering is ensured.
* It is valid to reuse and free a dequeued node immediately.
- * Should be called with cds_wfcq_dequeue_lock() held.
+ * Dequeue/splice/iteration mutual exclusion should be ensured by the
+ * caller.
*/
static inline struct cds_wfcq_node *
___cds_wfcq_dequeue_blocking(struct cds_wfcq_head *head,
*
* Dequeue all nodes from src_q.
* dest_q must be already initialized.
- * Should be called with cds_wfcq_dequeue_lock() held on src_q.
+ * Dequeue/splice/iteration mutual exclusion for src_q should be ensured
+ * by the caller.
*/
static inline void
___cds_wfcq_splice_blocking(
*
* Content written into the node before enqueue is guaranteed to be
* consistent, but no other memory ordering is ensured.
- * Mutual exlusion with (and only with) cds_wfcq_splice_blocking is
+ * Mutual exlusion with cds_wfcq_splice_blocking and dequeue lock is
* ensured.
* It is valid to reuse and free a dequeued node immediately.
*/
* dest_q must be already initialized.
* Content written into the node before enqueue is guaranteed to be
* consistent, but no other memory ordering is ensured.
- * Mutual exlusion with (and only with) cds_wfcq_dequeue_blocking is
+ * Mutual exlusion with cds_wfcq_dequeue_blocking and dequeue lock is
* ensured.
*/
static inline void
*
* For convenience, cds_wfcq_dequeue_blocking() and
* cds_wfcq_splice_blocking() hold the dequeue lock.
+ *
+ * Besides locking, mutual exclusion of dequeue, splice and iteration
+ * can be ensured by performing all of those operations from a single
+ * thread, without requiring any lock.
*/
/*
* Content written into the node before enqueue is guaranteed to be
* consistent, but no other memory ordering is ensured.
* It is valid to reuse and free a dequeued node immediately.
- * Mutual exlusion with dequeuers is ensured internally.
+ * Mutual exlusion with cds_wfcq_dequeue_blocking and dequeue lock is
+ * ensured.
*/
extern struct cds_wfcq_node *cds_wfcq_dequeue_blocking(
struct cds_wfcq_head *head,
* dest_q must be already initialized.
* Content written into the node before enqueue is guaranteed to be
* consistent, but no other memory ordering is ensured.
- * Mutual exlusion with dequeuers is ensured internally.
+ * Mutual exlusion with cds_wfcq_dequeue_blocking and dequeue lock is
+ * ensured.
*/
extern void cds_wfcq_splice_blocking(
struct cds_wfcq_head *dest_q_head,
* Content written into the node before enqueue is guaranteed to be
* consistent, but no other memory ordering is ensured.
* It is valid to reuse and free a dequeued node immediately.
- * Should be called with cds_wfcq_dequeue_lock() held.
+ * Dequeue/splice/iteration mutual exclusion should be ensured by the
+ * caller.
*/
extern struct cds_wfcq_node *__cds_wfcq_dequeue_blocking(
struct cds_wfcq_head *head,
* dest_q must be already initialized.
* Content written into the node before enqueue is guaranteed to be
* consistent, but no other memory ordering is ensured.
- * Should be called with cds_wfcq_dequeue_lock() held.
+ * Dequeue/splice/iteration mutual exclusion for src_q should be ensured
+ * by the caller.
*/
extern void __cds_wfcq_splice_blocking(
struct cds_wfcq_head *dest_q_head,
*
* Content written into the node before enqueue is guaranteed to be
* consistent, but no other memory ordering is ensured.
- * Should be called with cds_wfcq_dequeue_lock() held.
+ * Dequeue/splice/iteration mutual exclusion should be ensured by the
+ * caller.
*
* Used by for-like iteration macros:
* __cds_wfcq_for_each_blocking()
*
* Content written into the node before enqueue is guaranteed to be
* consistent, but no other memory ordering is ensured.
- * Should be called with cds_wfcq_dequeue_lock() held.
+ * Dequeue/splice/iteration mutual exclusion should be ensured by the
+ * caller.
*
* Used by for-like iteration macros:
* __cds_wfcq_for_each_blocking()
*
* Content written into each node before enqueue is guaranteed to be
* consistent, but no other memory ordering is ensured.
- * Should be called with cds_wfcq_dequeue_lock() held.
+ * Dequeue/splice/iteration mutual exclusion should be ensured by the
+ * caller.
*/
#define __cds_wfcq_for_each_blocking(head, tail, node) \
for (node = __cds_wfcq_first_blocking(head, tail); \
*
* Content written into each node before enqueue is guaranteed to be
* consistent, but no other memory ordering is ensured.
- * Should be called with cds_wfcq_dequeue_lock() held.
+ * Dequeue/splice/iteration mutual exclusion should be ensured by the
+ * caller.
*/
#define __cds_wfcq_for_each_blocking_safe(head, tail, node, n) \
for (node = __cds_wfcq_first_blocking(head, tail), \
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