}
/*
- * cds_wfcq_init: initialize wait-free queue.
+ * cds_wfcq_init: initialize wait-free queue (with lock). Pair with
+ * cds_wfcq_destroy().
*/
static inline void _cds_wfcq_init(struct cds_wfcq_head *head,
struct cds_wfcq_tail *tail)
assert(!ret);
}
+/*
+ * cds_wfcq_destroy: destroy wait-free queue (with lock). Pair with
+ * cds_wfcq_init().
+ */
+static inline void _cds_wfcq_destroy(struct cds_wfcq_head *head,
+ struct cds_wfcq_tail *tail)
+{
+ int ret = pthread_mutex_destroy(&head->lock);
+ assert(!ret);
+}
+
+/*
+ * __cds_wfcq_init: initialize wait-free queue (without lock). Don't
+ * pair with any destroy function.
+ */
+static inline void ___cds_wfcq_init(struct __cds_wfcq_head *head,
+ struct cds_wfcq_tail *tail)
+{
+ /* Set queue head and tail */
+ _cds_wfcq_node_init(&head->node);
+ tail->p = &head->node;
+}
+
/*
* cds_wfcq_empty: return whether wait-free queue is empty.
*
* make a queue appear empty if an enqueuer is preempted for a long time
* between xchg() and setting the previous node's next pointer.
*/
-static inline bool _cds_wfcq_empty(struct cds_wfcq_head *head,
+static inline bool _cds_wfcq_empty(cds_wfcq_head_ptr_t u_head,
struct cds_wfcq_tail *tail)
{
+ struct __cds_wfcq_head *head = u_head._h;
/*
* Queue is empty if no node is pointed by head->node.next nor
* tail->p. Even though the tail->p check is sufficient to find
assert(!ret);
}
-static inline bool ___cds_wfcq_append(struct cds_wfcq_head *head,
+static inline bool ___cds_wfcq_append(cds_wfcq_head_ptr_t u_head,
struct cds_wfcq_tail *tail,
struct cds_wfcq_node *new_head,
struct cds_wfcq_node *new_tail)
{
+ struct __cds_wfcq_head *head = u_head._h;
struct cds_wfcq_node *old_tail;
/*
* Returns false if the queue was empty prior to adding the node.
* Returns true otherwise.
*/
-static inline bool _cds_wfcq_enqueue(struct cds_wfcq_head *head,
+static inline bool _cds_wfcq_enqueue(cds_wfcq_head_ptr_t head,
struct cds_wfcq_tail *tail,
struct cds_wfcq_node *new_tail)
{
if (!blocking)
return 1;
if (++(*attempt) >= WFCQ_ADAPT_ATTEMPTS) {
- poll(NULL, 0, WFCQ_WAIT); /* Wait for 10ms */
+ (void) poll(NULL, 0, WFCQ_WAIT); /* Wait for 10ms */
*attempt = 0;
} else {
caa_cpu_relax();
}
static inline struct cds_wfcq_node *
-___cds_wfcq_first(struct cds_wfcq_head *head,
+___cds_wfcq_first(cds_wfcq_head_ptr_t u_head,
struct cds_wfcq_tail *tail,
int blocking)
{
+ struct __cds_wfcq_head *head = u_head._h;
struct cds_wfcq_node *node;
- if (_cds_wfcq_empty(head, tail))
+ if (_cds_wfcq_empty(__cds_wfcq_head_cast(head), tail))
return NULL;
node = ___cds_wfcq_node_sync_next(&head->node, blocking);
/* Load head->node.next before loading node's content */
* Used by for-like iteration macros in urcu/wfqueue.h:
* __cds_wfcq_for_each_blocking()
* __cds_wfcq_for_each_blocking_safe()
+ *
+ * Returns NULL if queue is empty, first node otherwise.
*/
static inline struct cds_wfcq_node *
-___cds_wfcq_first_blocking(struct cds_wfcq_head *head,
+___cds_wfcq_first_blocking(cds_wfcq_head_ptr_t head,
struct cds_wfcq_tail *tail)
{
return ___cds_wfcq_first(head, tail, 1);
* it needs to block.
*/
static inline struct cds_wfcq_node *
-___cds_wfcq_first_nonblocking(struct cds_wfcq_head *head,
+___cds_wfcq_first_nonblocking(cds_wfcq_head_ptr_t head,
struct cds_wfcq_tail *tail)
{
return ___cds_wfcq_first(head, tail, 0);
}
static inline struct cds_wfcq_node *
-___cds_wfcq_next(struct cds_wfcq_head *head,
+___cds_wfcq_next(cds_wfcq_head_ptr_t head,
struct cds_wfcq_tail *tail,
struct cds_wfcq_node *node,
int blocking)
* Used by for-like iteration macros in urcu/wfqueue.h:
* __cds_wfcq_for_each_blocking()
* __cds_wfcq_for_each_blocking_safe()
+ *
+ * Returns NULL if reached end of queue, non-NULL next queue node
+ * otherwise.
*/
static inline struct cds_wfcq_node *
-___cds_wfcq_next_blocking(struct cds_wfcq_head *head,
+___cds_wfcq_next_blocking(cds_wfcq_head_ptr_t head,
struct cds_wfcq_tail *tail,
struct cds_wfcq_node *node)
{
* it needs to block.
*/
static inline struct cds_wfcq_node *
-___cds_wfcq_next_nonblocking(struct cds_wfcq_head *head,
+___cds_wfcq_next_nonblocking(cds_wfcq_head_ptr_t head,
struct cds_wfcq_tail *tail,
struct cds_wfcq_node *node)
{
}
static inline struct cds_wfcq_node *
-___cds_wfcq_dequeue(struct cds_wfcq_head *head,
+___cds_wfcq_dequeue_with_state(cds_wfcq_head_ptr_t u_head,
struct cds_wfcq_tail *tail,
+ int *state,
int blocking)
{
+ struct __cds_wfcq_head *head = u_head._h;
struct cds_wfcq_node *node, *next;
- if (_cds_wfcq_empty(head, tail))
+ if (state)
+ *state = 0;
+
+ if (_cds_wfcq_empty(__cds_wfcq_head_cast(head), tail)) {
return NULL;
+ }
node = ___cds_wfcq_node_sync_next(&head->node, blocking);
- if (!blocking && node == CDS_WFCQ_WOULDBLOCK)
+ if (!blocking && node == CDS_WFCQ_WOULDBLOCK) {
return CDS_WFCQ_WOULDBLOCK;
+ }
if ((next = CMM_LOAD_SHARED(node->next)) == NULL) {
/*
* content.
*/
_cds_wfcq_node_init(&head->node);
- if (uatomic_cmpxchg(&tail->p, node, &head->node) == node)
+ if (uatomic_cmpxchg(&tail->p, node, &head->node) == node) {
+ if (state)
+ *state |= CDS_WFCQ_STATE_LAST;
return node;
+ }
next = ___cds_wfcq_node_sync_next(node, blocking);
/*
* In nonblocking mode, if we would need to block to
}
/*
- * __cds_wfcq_dequeue_blocking: dequeue a node from the queue.
+ * __cds_wfcq_dequeue_with_state_blocking: dequeue node from queue, with state.
*
* Content written into the node before enqueue is guaranteed to be
* consistent, but no other memory ordering is ensured.
* caller.
*/
static inline struct cds_wfcq_node *
-___cds_wfcq_dequeue_blocking(struct cds_wfcq_head *head,
+___cds_wfcq_dequeue_with_state_blocking(cds_wfcq_head_ptr_t head,
+ struct cds_wfcq_tail *tail, int *state)
+{
+ return ___cds_wfcq_dequeue_with_state(head, tail, state, 1);
+}
+
+/*
+ * ___cds_wfcq_dequeue_blocking: dequeue node from queue.
+ *
+ * Same as __cds_wfcq_dequeue_with_state_blocking, but without saving
+ * state.
+ */
+static inline struct cds_wfcq_node *
+___cds_wfcq_dequeue_blocking(cds_wfcq_head_ptr_t head,
struct cds_wfcq_tail *tail)
{
- return ___cds_wfcq_dequeue(head, tail, 1);
+ return ___cds_wfcq_dequeue_with_state_blocking(head, tail, NULL);
}
/*
- * __cds_wfcq_dequeue_nonblocking: dequeue a node from a wait-free queue.
+ * __cds_wfcq_dequeue_with_state_nonblocking: dequeue node, with state.
*
* Same as __cds_wfcq_dequeue_blocking, but returns CDS_WFCQ_WOULDBLOCK
* if it needs to block.
*/
static inline struct cds_wfcq_node *
-___cds_wfcq_dequeue_nonblocking(struct cds_wfcq_head *head,
+___cds_wfcq_dequeue_with_state_nonblocking(cds_wfcq_head_ptr_t head,
+ struct cds_wfcq_tail *tail, int *state)
+{
+ return ___cds_wfcq_dequeue_with_state(head, tail, state, 0);
+}
+
+/*
+ * ___cds_wfcq_dequeue_nonblocking: dequeue node from queue.
+ *
+ * Same as __cds_wfcq_dequeue_with_state_nonblocking, but without saving
+ * state.
+ */
+static inline struct cds_wfcq_node *
+___cds_wfcq_dequeue_nonblocking(cds_wfcq_head_ptr_t head,
struct cds_wfcq_tail *tail)
{
- return ___cds_wfcq_dequeue(head, tail, 0);
+ return ___cds_wfcq_dequeue_with_state_nonblocking(head, tail, NULL);
}
/*
*/
static inline enum cds_wfcq_ret
___cds_wfcq_splice(
- struct cds_wfcq_head *dest_q_head,
+ cds_wfcq_head_ptr_t u_dest_q_head,
struct cds_wfcq_tail *dest_q_tail,
- struct cds_wfcq_head *src_q_head,
+ cds_wfcq_head_ptr_t u_src_q_head,
struct cds_wfcq_tail *src_q_tail,
int blocking)
{
+ struct __cds_wfcq_head *dest_q_head = u_dest_q_head._h;
+ struct __cds_wfcq_head *src_q_head = u_src_q_head._h;
struct cds_wfcq_node *head, *tail;
int attempt = 0;
* Initial emptiness check to speed up cases where queue is
* empty: only require loads to check if queue is empty.
*/
- if (_cds_wfcq_empty(src_q_head, src_q_tail))
+ if (_cds_wfcq_empty(__cds_wfcq_head_cast(src_q_head), src_q_tail))
return CDS_WFCQ_RET_SRC_EMPTY;
for (;;) {
* Append the spliced content of src_q into dest_q. Does not
* require mutual exclusion on dest_q (wait-free).
*/
- if (___cds_wfcq_append(dest_q_head, dest_q_tail, head, tail))
+ if (___cds_wfcq_append(__cds_wfcq_head_cast(dest_q_head), dest_q_tail,
+ head, tail))
return CDS_WFCQ_RET_DEST_NON_EMPTY;
else
return CDS_WFCQ_RET_DEST_EMPTY;
*/
static inline enum cds_wfcq_ret
___cds_wfcq_splice_blocking(
- struct cds_wfcq_head *dest_q_head,
+ cds_wfcq_head_ptr_t dest_q_head,
struct cds_wfcq_tail *dest_q_tail,
- struct cds_wfcq_head *src_q_head,
+ cds_wfcq_head_ptr_t src_q_head,
struct cds_wfcq_tail *src_q_tail)
{
return ___cds_wfcq_splice(dest_q_head, dest_q_tail,
*/
static inline enum cds_wfcq_ret
___cds_wfcq_splice_nonblocking(
- struct cds_wfcq_head *dest_q_head,
+ cds_wfcq_head_ptr_t dest_q_head,
struct cds_wfcq_tail *dest_q_tail,
- struct cds_wfcq_head *src_q_head,
+ cds_wfcq_head_ptr_t src_q_head,
struct cds_wfcq_tail *src_q_tail)
{
return ___cds_wfcq_splice(dest_q_head, dest_q_tail,
}
/*
- * cds_wfcq_dequeue_blocking: dequeue a node from a wait-free queue.
+ * cds_wfcq_dequeue_with_state_blocking: dequeue a node from a wait-free queue.
*
* Content written into the node before enqueue is guaranteed to be
* consistent, but no other memory ordering is ensured.
- * Mutual exlusion with cds_wfcq_splice_blocking and dequeue lock is
+ * Mutual exclusion with cds_wfcq_splice_blocking and dequeue lock is
* ensured.
* It is valid to reuse and free a dequeued node immediately.
*/
static inline struct cds_wfcq_node *
-_cds_wfcq_dequeue_blocking(struct cds_wfcq_head *head,
- struct cds_wfcq_tail *tail)
+_cds_wfcq_dequeue_with_state_blocking(struct cds_wfcq_head *head,
+ struct cds_wfcq_tail *tail, int *state)
{
struct cds_wfcq_node *retval;
_cds_wfcq_dequeue_lock(head, tail);
- retval = ___cds_wfcq_dequeue_blocking(head, tail);
+ retval = ___cds_wfcq_dequeue_with_state_blocking(cds_wfcq_head_cast(head),
+ tail, state);
_cds_wfcq_dequeue_unlock(head, tail);
return retval;
}
+/*
+ * cds_wfcq_dequeue_blocking: dequeue node from queue.
+ *
+ * Same as cds_wfcq_dequeue_blocking, but without saving state.
+ */
+static inline struct cds_wfcq_node *
+_cds_wfcq_dequeue_blocking(struct cds_wfcq_head *head,
+ struct cds_wfcq_tail *tail)
+{
+ return _cds_wfcq_dequeue_with_state_blocking(head, tail, NULL);
+}
+
/*
* cds_wfcq_splice_blocking: enqueue all src_q nodes at the end of dest_q.
*
* 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 cds_wfcq_dequeue_blocking and dequeue lock is
+ * Mutual exclusion with cds_wfcq_dequeue_blocking and dequeue lock is
* ensured.
* Returns enum cds_wfcq_ret which indicates the state of the src or
* dest queue. Never returns CDS_WFCQ_RET_WOULDBLOCK.
enum cds_wfcq_ret ret;
_cds_wfcq_dequeue_lock(src_q_head, src_q_tail);
- ret = ___cds_wfcq_splice_blocking(dest_q_head, dest_q_tail,
- src_q_head, src_q_tail);
+ ret = ___cds_wfcq_splice_blocking(cds_wfcq_head_cast(dest_q_head), dest_q_tail,
+ cds_wfcq_head_cast(src_q_head), src_q_tail);
_cds_wfcq_dequeue_unlock(src_q_head, src_q_tail);
return ret;
}
projects / urcu.git / blobdiff