[lttng-dev] [RFC PATCH urcu] Add "last" output parameter to pop/dequeue
Mathieu Desnoyers
mathieu.desnoyers at efficios.com
Thu Dec 13 06:44:56 EST 2012
I noticed that in addition to having:
- push/enqueue returning whether the stack/queue was empty prior to the
operation,
- pop_all/splice, by nature, emptying the stack/queue,
it can be interesting to make pop/dequeue operations return whether they
are returning the last element of the stack/queue (therefore emptying
it). This allow extending the test-cases covering the number of empty
stack/queue encountered by both push/enqueuer and pop/dequeuer threads
not only to push/enqueue paired with pop_all/splice, but also to
pop/dequeue.
In the case of wfstack, this unfortunately requires to modify an already
exposed API. As a RFC, one question we should answer is how we want to
handle the way forward: should we add new functions to the wfstack API
and leave the existing ones alone ?
Thoughts ?
Thanks,
Mathieu
---
diff --git a/tests/test_urcu_wfcq.c b/tests/test_urcu_wfcq.c
index 91285a5..de9566d 100644
--- a/tests/test_urcu_wfcq.c
+++ b/tests/test_urcu_wfcq.c
@@ -168,6 +168,7 @@ static DEFINE_URCU_TLS(unsigned long long, nr_successful_dequeues);
static DEFINE_URCU_TLS(unsigned long long, nr_successful_enqueues);
static DEFINE_URCU_TLS(unsigned long long, nr_empty_dest_enqueues);
static DEFINE_URCU_TLS(unsigned long long, nr_splice);
+static DEFINE_URCU_TLS(unsigned long long, nr_dequeue_last);
static unsigned int nr_enqueuers;
static unsigned int nr_dequeuers;
@@ -228,11 +229,15 @@ fail:
static void do_test_dequeue(enum test_sync sync)
{
struct cds_wfcq_node *node;
+ bool last;
if (sync == TEST_SYNC_MUTEX)
- node = cds_wfcq_dequeue_blocking(&head, &tail);
+ node = cds_wfcq_dequeue_blocking(&head, &tail, &last);
else
- node = __cds_wfcq_dequeue_blocking(&head, &tail);
+ node = __cds_wfcq_dequeue_blocking(&head, &tail, &last);
+
+ if (last)
+ URCU_TLS(nr_dequeue_last)++;
if (node) {
free(node);
@@ -263,6 +268,7 @@ static void do_test_splice(enum test_sync sync)
break;
case CDS_WFCQ_RET_DEST_EMPTY:
URCU_TLS(nr_splice)++;
+ URCU_TLS(nr_dequeue_last)++;
/* ok */
break;
case CDS_WFCQ_RET_DEST_NON_EMPTY:
@@ -325,16 +331,21 @@ static void *thr_dequeuer(void *_count)
count[0] = URCU_TLS(nr_dequeues);
count[1] = URCU_TLS(nr_successful_dequeues);
count[2] = URCU_TLS(nr_splice);
+ count[3] = URCU_TLS(nr_dequeue_last);
return ((void*)2);
}
-static void test_end(unsigned long long *nr_dequeues)
+static void test_end(unsigned long long *nr_dequeues,
+ unsigned long long *nr_dequeue_last)
{
struct cds_wfcq_node *node;
+ bool last;
do {
- node = cds_wfcq_dequeue_blocking(&head, &tail);
+ node = cds_wfcq_dequeue_blocking(&head, &tail, &last);
if (node) {
+ if (last)
+ (*nr_dequeue_last)++;
free(node);
(*nr_dequeues)++;
}
@@ -367,7 +378,7 @@ int main(int argc, char **argv)
unsigned long long tot_successful_enqueues = 0,
tot_successful_dequeues = 0,
tot_empty_dest_enqueues = 0,
- tot_splice = 0;
+ tot_splice = 0, tot_dequeue_last = 0;
unsigned long long end_dequeues = 0;
int i, a, retval = 0;
@@ -480,7 +491,7 @@ int main(int argc, char **argv)
tid_enqueuer = malloc(sizeof(*tid_enqueuer) * nr_enqueuers);
tid_dequeuer = malloc(sizeof(*tid_dequeuer) * nr_dequeuers);
count_enqueuer = malloc(3 * sizeof(*count_enqueuer) * nr_enqueuers);
- count_dequeuer = malloc(3 * sizeof(*count_dequeuer) * nr_dequeuers);
+ count_dequeuer = malloc(4 * sizeof(*count_dequeuer) * nr_dequeuers);
cds_wfcq_init(&head, &tail);
next_aff = 0;
@@ -493,7 +504,7 @@ int main(int argc, char **argv)
}
for (i = 0; i < nr_dequeuers; i++) {
err = pthread_create(&tid_dequeuer[i], NULL, thr_dequeuer,
- &count_dequeuer[3 * i]);
+ &count_dequeuer[4 * i]);
if (err != 0)
exit(1);
}
@@ -533,34 +544,37 @@ int main(int argc, char **argv)
err = pthread_join(tid_dequeuer[i], &tret);
if (err != 0)
exit(1);
- tot_dequeues += count_dequeuer[3 * i];
- tot_successful_dequeues += count_dequeuer[3 * i + 1];
- tot_splice += count_dequeuer[3 * i + 2];
+ tot_dequeues += count_dequeuer[4 * i];
+ tot_successful_dequeues += count_dequeuer[4 * i + 1];
+ tot_splice += count_dequeuer[4 * i + 2];
+ tot_dequeue_last += count_dequeuer[4 * i + 3];
}
- test_end(&end_dequeues);
+ test_end(&end_dequeues, &tot_dequeue_last);
printf_verbose("total number of enqueues : %llu, dequeues %llu\n",
tot_enqueues, tot_dequeues);
printf_verbose("total number of successful enqueues : %llu, "
"enqueues to empty dest : %llu, "
"successful dequeues %llu, "
- "splice : %llu\n",
+ "splice : %llu, dequeue_last : %llu\n",
tot_successful_enqueues,
tot_empty_dest_enqueues,
tot_successful_dequeues,
- tot_splice);
+ tot_splice, tot_dequeue_last);
printf("SUMMARY %-25s testdur %4lu nr_enqueuers %3u wdelay %6lu "
"nr_dequeuers %3u "
"rdur %6lu nr_enqueues %12llu nr_dequeues %12llu "
"successful enqueues %12llu enqueues to empty dest %12llu "
"successful dequeues %12llu splice %12llu "
+ "dequeue_last %llu "
"end_dequeues %llu nr_ops %12llu\n",
argv[0], duration, nr_enqueuers, wdelay,
nr_dequeuers, rduration, tot_enqueues, tot_dequeues,
tot_successful_enqueues,
tot_empty_dest_enqueues,
- tot_successful_dequeues, tot_splice, end_dequeues,
+ tot_successful_dequeues, tot_splice, tot_dequeue_last,
+ end_dequeues,
tot_enqueues + tot_dequeues);
if (tot_successful_enqueues != tot_successful_dequeues + end_dequeues) {
@@ -576,12 +590,11 @@ int main(int argc, char **argv)
* exactly as many empty queues than the number of non-empty
* src splice.
*/
- if (test_wait_empty && test_splice && !test_dequeue
- && tot_empty_dest_enqueues != tot_splice) {
+ if (tot_empty_dest_enqueues != tot_dequeue_last) {
printf("WARNING! Discrepancy between empty enqueue (%llu) and "
- "number of non-empty splice (%llu)\n",
+ "number of dequeue of last element (%llu)\n",
tot_empty_dest_enqueues,
- tot_splice);
+ tot_dequeue_last);
retval = 1;
}
free(count_enqueuer);
diff --git a/tests/test_urcu_wfs.c b/tests/test_urcu_wfs.c
index 259ca24..6c54153 100644
--- a/tests/test_urcu_wfs.c
+++ b/tests/test_urcu_wfs.c
@@ -171,6 +171,7 @@ static DEFINE_URCU_TLS(unsigned long long, nr_successful_dequeues);
static DEFINE_URCU_TLS(unsigned long long, nr_successful_enqueues);
static DEFINE_URCU_TLS(unsigned long long, nr_empty_dest_enqueues);
static DEFINE_URCU_TLS(unsigned long long, nr_pop_all);
+static DEFINE_URCU_TLS(unsigned long long, nr_pop_last);
static unsigned int nr_enqueuers;
static unsigned int nr_dequeuers;
@@ -230,14 +231,17 @@ fail:
static void do_test_pop(enum test_sync sync)
{
struct cds_wfs_node *node;
+ bool last;
if (sync == TEST_SYNC_MUTEX)
cds_wfs_pop_lock(&s);
- node = __cds_wfs_pop_blocking(&s);
+ node = __cds_wfs_pop_blocking(&s, &last);
if (sync == TEST_SYNC_MUTEX)
cds_wfs_pop_unlock(&s);
if (node) {
+ if (last)
+ URCU_TLS(nr_pop_last)++;
free(node);
URCU_TLS(nr_successful_dequeues)++;
}
@@ -260,6 +264,7 @@ static void do_test_pop_all(enum test_sync sync)
return;
URCU_TLS(nr_pop_all)++;
+ URCU_TLS(nr_pop_last)++;
cds_wfs_for_each_blocking_safe(head, node, n) {
free(node);
@@ -308,24 +313,30 @@ static void *thr_dequeuer(void *_count)
printf_verbose("dequeuer thread_end, thread id : %lx, tid %lu, "
"dequeues %llu, successful_dequeues %llu "
- "pop_all %llu\n",
+ "pop_all %llu pop_last %llu\n",
pthread_self(),
(unsigned long) gettid(),
URCU_TLS(nr_dequeues), URCU_TLS(nr_successful_dequeues),
- URCU_TLS(nr_pop_all));
+ URCU_TLS(nr_pop_all),
+ URCU_TLS(nr_pop_last));
count[0] = URCU_TLS(nr_dequeues);
count[1] = URCU_TLS(nr_successful_dequeues);
count[2] = URCU_TLS(nr_pop_all);
+ count[3] = URCU_TLS(nr_pop_last);
return ((void*)2);
}
-static void test_end(struct cds_wfs_stack *s, unsigned long long *nr_dequeues)
+static void test_end(struct cds_wfs_stack *s, unsigned long long *nr_dequeues,
+ unsigned long long *nr_pop_last)
{
struct cds_wfs_node *node;
+ bool last;
do {
- node = cds_wfs_pop_blocking(s);
+ node = cds_wfs_pop_blocking(s, &last);
if (node) {
+ if (last)
+ (*nr_pop_last)++;
free(node);
(*nr_dequeues)++;
}
@@ -358,7 +369,7 @@ int main(int argc, char **argv)
unsigned long long tot_successful_enqueues = 0,
tot_successful_dequeues = 0,
tot_empty_dest_enqueues = 0,
- tot_pop_all = 0;
+ tot_pop_all = 0, tot_pop_last = 0;
unsigned long long end_dequeues = 0;
int i, a, retval = 0;
@@ -471,7 +482,7 @@ int main(int argc, char **argv)
tid_enqueuer = malloc(sizeof(*tid_enqueuer) * nr_enqueuers);
tid_dequeuer = malloc(sizeof(*tid_dequeuer) * nr_dequeuers);
count_enqueuer = malloc(3 * sizeof(*count_enqueuer) * nr_enqueuers);
- count_dequeuer = malloc(3 * sizeof(*count_dequeuer) * nr_dequeuers);
+ count_dequeuer = malloc(4 * sizeof(*count_dequeuer) * nr_dequeuers);
cds_wfs_init(&s);
next_aff = 0;
@@ -484,7 +495,7 @@ int main(int argc, char **argv)
}
for (i = 0; i < nr_dequeuers; i++) {
err = pthread_create(&tid_dequeuer[i], NULL, thr_dequeuer,
- &count_dequeuer[3 * i]);
+ &count_dequeuer[4 * i]);
if (err != 0)
exit(1);
}
@@ -524,34 +535,36 @@ int main(int argc, char **argv)
err = pthread_join(tid_dequeuer[i], &tret);
if (err != 0)
exit(1);
- tot_dequeues += count_dequeuer[3 * i];
- tot_successful_dequeues += count_dequeuer[3 * i + 1];
- tot_pop_all += count_dequeuer[3 * i + 2];
+ tot_dequeues += count_dequeuer[4 * i];
+ tot_successful_dequeues += count_dequeuer[4 * i + 1];
+ tot_pop_all += count_dequeuer[4 * i + 2];
+ tot_pop_last += count_dequeuer[4 * i + 3];
}
- test_end(&s, &end_dequeues);
+ test_end(&s, &end_dequeues, &tot_pop_last);
printf_verbose("total number of enqueues : %llu, dequeues %llu\n",
tot_enqueues, tot_dequeues);
printf_verbose("total number of successful enqueues : %llu, "
"enqueues to empty dest : %llu, "
"successful dequeues %llu, "
- "pop_all : %llu\n",
+ "pop_all : %llu, pop_last : %llu\n",
tot_successful_enqueues,
tot_empty_dest_enqueues,
tot_successful_dequeues,
- tot_pop_all);
+ tot_pop_all, tot_pop_last);
printf("SUMMARY %-25s testdur %4lu nr_enqueuers %3u wdelay %6lu "
"nr_dequeuers %3u "
"rdur %6lu nr_enqueues %12llu nr_dequeues %12llu "
"successful enqueues %12llu enqueues to empty dest %12llu "
"successful dequeues %12llu pop_all %12llu "
- "end_dequeues %llu nr_ops %12llu\n",
+ "pop_last %llu end_dequeues %llu nr_ops %12llu\n",
argv[0], duration, nr_enqueuers, wdelay,
nr_dequeuers, rduration, tot_enqueues, tot_dequeues,
tot_successful_enqueues,
tot_empty_dest_enqueues,
- tot_successful_dequeues, tot_pop_all, end_dequeues,
+ tot_successful_dequeues, tot_pop_all, tot_pop_last,
+ end_dequeues,
tot_enqueues + tot_dequeues);
if (tot_successful_enqueues != tot_successful_dequeues + end_dequeues) {
printf("WARNING! Discrepancy between nr succ. enqueues %llu vs "
@@ -561,16 +574,14 @@ int main(int argc, char **argv)
retval = 1;
}
/*
- * If only using pop_all to dequeue, the enqueuer should see
- * exactly as many empty queues than the number of non-empty
- * stacks dequeued.
+ * The enqueuer should see exactly as many empty queues than the
+ * number of non-empty stacks dequeued.
*/
- if (test_wait_empty && test_pop_all && !test_pop
- && tot_empty_dest_enqueues != tot_pop_all) {
+ if (tot_empty_dest_enqueues != tot_pop_last) {
printf("WARNING! Discrepancy between empty enqueue (%llu) and "
- "number of non-empty pop_all (%llu)\n",
+ "number of pop last (%llu)\n",
tot_empty_dest_enqueues,
- tot_pop_all);
+ tot_pop_last);
retval = 1;
}
free(count_enqueuer);
diff --git a/urcu/static/wfcqueue.h b/urcu/static/wfcqueue.h
index 4b3535a..33c99ed 100644
--- a/urcu/static/wfcqueue.h
+++ b/urcu/static/wfcqueue.h
@@ -352,16 +352,23 @@ ___cds_wfcq_next_nonblocking(struct cds_wfcq_head *head,
static inline struct cds_wfcq_node *
___cds_wfcq_dequeue(struct cds_wfcq_head *head,
struct cds_wfcq_tail *tail,
+ bool *last,
int blocking)
{
struct cds_wfcq_node *node, *next;
- if (_cds_wfcq_empty(head, tail))
+ if (_cds_wfcq_empty(head, tail)) {
+ if (last)
+ *last = 0;
return NULL;
+ }
node = ___cds_wfcq_node_sync_next(&head->node, blocking);
- if (!blocking && node == CDS_WFCQ_WOULDBLOCK)
+ if (!blocking && node == CDS_WFCQ_WOULDBLOCK) {
+ if (last)
+ *last = 0;
return CDS_WFCQ_WOULDBLOCK;
+ }
if ((next = CMM_LOAD_SHARED(node->next)) == NULL) {
/*
@@ -379,8 +386,11 @@ ___cds_wfcq_dequeue(struct cds_wfcq_head *head,
* 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 (last)
+ *last = 1;
return node;
+ }
next = ___cds_wfcq_node_sync_next(node, blocking);
/*
* In nonblocking mode, if we would need to block to
@@ -389,6 +399,8 @@ ___cds_wfcq_dequeue(struct cds_wfcq_head *head,
*/
if (!blocking && next == CDS_WFCQ_WOULDBLOCK) {
head->node.next = node;
+ if (last)
+ *last = 0;
return CDS_WFCQ_WOULDBLOCK;
}
}
@@ -400,6 +412,8 @@ ___cds_wfcq_dequeue(struct cds_wfcq_head *head,
/* Load q->head.next before loading node's content */
cmm_smp_read_barrier_depends();
+ if (last)
+ *last = 0;
return node;
}
@@ -414,9 +428,9 @@ ___cds_wfcq_dequeue(struct cds_wfcq_head *head,
*/
static inline struct cds_wfcq_node *
___cds_wfcq_dequeue_blocking(struct cds_wfcq_head *head,
- struct cds_wfcq_tail *tail)
+ struct cds_wfcq_tail *tail, bool *last)
{
- return ___cds_wfcq_dequeue(head, tail, 1);
+ return ___cds_wfcq_dequeue(head, tail, last, 1);
}
/*
@@ -427,9 +441,9 @@ ___cds_wfcq_dequeue_blocking(struct cds_wfcq_head *head,
*/
static inline struct cds_wfcq_node *
___cds_wfcq_dequeue_nonblocking(struct cds_wfcq_head *head,
- struct cds_wfcq_tail *tail)
+ struct cds_wfcq_tail *tail, bool *last)
{
- return ___cds_wfcq_dequeue(head, tail, 0);
+ return ___cds_wfcq_dequeue(head, tail, last, 0);
}
/*
@@ -542,12 +556,12 @@ ___cds_wfcq_splice_nonblocking(
*/
static inline struct cds_wfcq_node *
_cds_wfcq_dequeue_blocking(struct cds_wfcq_head *head,
- struct cds_wfcq_tail *tail)
+ struct cds_wfcq_tail *tail, bool *last)
{
struct cds_wfcq_node *retval;
_cds_wfcq_dequeue_lock(head, tail);
- retval = ___cds_wfcq_dequeue_blocking(head, tail);
+ retval = ___cds_wfcq_dequeue_blocking(head, tail, last);
_cds_wfcq_dequeue_unlock(head, tail);
return retval;
}
diff --git a/urcu/static/wfstack.h b/urcu/static/wfstack.h
index 9bc9519..2ebda27 100644
--- a/urcu/static/wfstack.h
+++ b/urcu/static/wfstack.h
@@ -161,23 +161,35 @@ ___cds_wfs_node_sync_next(struct cds_wfs_node *node, int blocking)
static inline
struct cds_wfs_node *
-___cds_wfs_pop(struct cds_wfs_stack *s, int blocking)
+___cds_wfs_pop(struct cds_wfs_stack *s, bool *last, int blocking)
{
struct cds_wfs_head *head, *new_head;
struct cds_wfs_node *next;
for (;;) {
head = CMM_LOAD_SHARED(s->head);
- if (___cds_wfs_end(head))
+ if (___cds_wfs_end(head)) {
+ if (last)
+ *last = 0;
return NULL;
+ }
next = ___cds_wfs_node_sync_next(&head->node, blocking);
- if (!blocking && next == CDS_WFS_WOULDBLOCK)
+ if (!blocking && next == CDS_WFS_WOULDBLOCK) {
+ if (last)
+ *last = 0;
return CDS_WFS_WOULDBLOCK;
+ }
new_head = caa_container_of(next, struct cds_wfs_head, node);
- if (uatomic_cmpxchg(&s->head, head, new_head) == head)
+ if (uatomic_cmpxchg(&s->head, head, new_head) == head) {
+ if (last)
+ *last = ___cds_wfs_end(new_head);
return &head->node;
- if (!blocking)
+ }
+ if (!blocking) {
+ if (last)
+ *last = 0;
return CDS_WFS_WOULDBLOCK;
+ }
/* busy-loop if head changed under us */
}
}
@@ -200,9 +212,9 @@ ___cds_wfs_pop(struct cds_wfs_stack *s, int blocking)
*/
static inline
struct cds_wfs_node *
-___cds_wfs_pop_blocking(struct cds_wfs_stack *s)
+___cds_wfs_pop_blocking(struct cds_wfs_stack *s, bool *last)
{
- return ___cds_wfs_pop(s, 1);
+ return ___cds_wfs_pop(s, last, 1);
}
/*
@@ -213,9 +225,9 @@ ___cds_wfs_pop_blocking(struct cds_wfs_stack *s)
*/
static inline
struct cds_wfs_node *
-___cds_wfs_pop_nonblocking(struct cds_wfs_stack *s)
+___cds_wfs_pop_nonblocking(struct cds_wfs_stack *s, bool *last)
{
- return ___cds_wfs_pop(s, 0);
+ return ___cds_wfs_pop(s, last, 0);
}
/*
@@ -284,12 +296,12 @@ static inline void _cds_wfs_pop_unlock(struct cds_wfs_stack *s)
*/
static inline
struct cds_wfs_node *
-_cds_wfs_pop_blocking(struct cds_wfs_stack *s)
+_cds_wfs_pop_blocking(struct cds_wfs_stack *s, bool *last)
{
struct cds_wfs_node *retnode;
_cds_wfs_pop_lock(s);
- retnode = ___cds_wfs_pop_blocking(s);
+ retnode = ___cds_wfs_pop_blocking(s, last);
_cds_wfs_pop_unlock(s);
return retnode;
}
diff --git a/urcu/wfcqueue.h b/urcu/wfcqueue.h
index b6be9f3..4b9e73b 100644
--- a/urcu/wfcqueue.h
+++ b/urcu/wfcqueue.h
@@ -197,7 +197,8 @@ extern bool cds_wfcq_enqueue(struct cds_wfcq_head *head,
*/
extern struct cds_wfcq_node *cds_wfcq_dequeue_blocking(
struct cds_wfcq_head *head,
- struct cds_wfcq_tail *tail);
+ struct cds_wfcq_tail *tail,
+ bool *last);
/*
* cds_wfcq_splice_blocking: enqueue all src_q nodes at the end of dest_q.
@@ -229,7 +230,8 @@ extern enum cds_wfcq_ret cds_wfcq_splice_blocking(
*/
extern struct cds_wfcq_node *__cds_wfcq_dequeue_blocking(
struct cds_wfcq_head *head,
- struct cds_wfcq_tail *tail);
+ struct cds_wfcq_tail *tail,
+ bool *last);
/*
* __cds_wfcq_dequeue_nonblocking: dequeue a node from a wait-free queue.
@@ -239,7 +241,8 @@ extern struct cds_wfcq_node *__cds_wfcq_dequeue_blocking(
*/
extern struct cds_wfcq_node *__cds_wfcq_dequeue_nonblocking(
struct cds_wfcq_head *head,
- struct cds_wfcq_tail *tail);
+ struct cds_wfcq_tail *tail,
+ bool *last);
/*
* __cds_wfcq_splice_blocking: enqueue all src_q nodes at the end of dest_q.
diff --git a/urcu/wfstack.h b/urcu/wfstack.h
index 03fee8f..1e4b848 100644
--- a/urcu/wfstack.h
+++ b/urcu/wfstack.h
@@ -147,7 +147,8 @@ extern int cds_wfs_push(struct cds_wfs_stack *s, struct cds_wfs_node *node);
*
* Calls __cds_wfs_pop_blocking with an internal pop mutex held.
*/
-extern struct cds_wfs_node *cds_wfs_pop_blocking(struct cds_wfs_stack *s);
+extern struct cds_wfs_node *cds_wfs_pop_blocking(struct cds_wfs_stack *s,
+ bool *last);
/*
* cds_wfs_pop_all_blocking: pop all nodes from a stack.
@@ -219,7 +220,8 @@ extern void cds_wfs_pop_unlock(struct cds_wfs_stack *s);
* 3) Ensuring that only ONE thread can call __cds_wfs_pop_blocking()
* and __cds_wfs_pop_all(). (multi-provider/single-consumer scheme).
*/
-extern struct cds_wfs_node *__cds_wfs_pop_blocking(struct cds_wfs_stack *s);
+extern struct cds_wfs_node *__cds_wfs_pop_blocking(struct cds_wfs_stack *s,
+ bool *last);
/*
* __cds_wfs_pop_nonblocking: pop a node from the stack.
@@ -227,7 +229,8 @@ extern struct cds_wfs_node *__cds_wfs_pop_blocking(struct cds_wfs_stack *s);
* Same as __cds_wfs_pop_blocking, but returns CDS_WFS_WOULDBLOCK if
* it needs to block.
*/
-extern struct cds_wfs_node *__cds_wfs_pop_nonblocking(struct cds_wfs_stack *s);
+extern struct cds_wfs_node *__cds_wfs_pop_nonblocking(struct cds_wfs_stack *s,
+ bool *last);
/*
* __cds_wfs_pop_all: pop all nodes from a stack.
diff --git a/wfcqueue.c b/wfcqueue.c
index ab0eb93..7baefdf 100644
--- a/wfcqueue.c
+++ b/wfcqueue.c
@@ -68,9 +68,10 @@ void cds_wfcq_dequeue_unlock(struct cds_wfcq_head *head,
struct cds_wfcq_node *cds_wfcq_dequeue_blocking(
struct cds_wfcq_head *head,
- struct cds_wfcq_tail *tail)
+ struct cds_wfcq_tail *tail,
+ bool *last)
{
- return _cds_wfcq_dequeue_blocking(head, tail);
+ return _cds_wfcq_dequeue_blocking(head, tail, last);
}
enum cds_wfcq_ret cds_wfcq_splice_blocking(
@@ -85,16 +86,18 @@ enum cds_wfcq_ret cds_wfcq_splice_blocking(
struct cds_wfcq_node *__cds_wfcq_dequeue_blocking(
struct cds_wfcq_head *head,
- struct cds_wfcq_tail *tail)
+ struct cds_wfcq_tail *tail,
+ bool *last)
{
- return ___cds_wfcq_dequeue_blocking(head, tail);
+ return ___cds_wfcq_dequeue_blocking(head, tail, last);
}
struct cds_wfcq_node *__cds_wfcq_dequeue_nonblocking(
struct cds_wfcq_head *head,
- struct cds_wfcq_tail *tail)
+ struct cds_wfcq_tail *tail,
+ bool *last)
{
- return ___cds_wfcq_dequeue_nonblocking(head, tail);
+ return ___cds_wfcq_dequeue_nonblocking(head, tail, last);
}
enum cds_wfcq_ret __cds_wfcq_splice_blocking(
diff --git a/wfstack.c b/wfstack.c
index 4ccb6b9..041703b 100644
--- a/wfstack.c
+++ b/wfstack.c
@@ -48,9 +48,10 @@ int cds_wfs_push(struct cds_wfs_stack *s, struct cds_wfs_node *node)
return _cds_wfs_push(s, node);
}
-struct cds_wfs_node *cds_wfs_pop_blocking(struct cds_wfs_stack *s)
+struct cds_wfs_node *cds_wfs_pop_blocking(struct cds_wfs_stack *s,
+ bool *last)
{
- return _cds_wfs_pop_blocking(s);
+ return _cds_wfs_pop_blocking(s, last);
}
struct cds_wfs_head *cds_wfs_pop_all_blocking(struct cds_wfs_stack *s)
@@ -83,14 +84,16 @@ void cds_wfs_pop_unlock(struct cds_wfs_stack *s)
_cds_wfs_pop_unlock(s);
}
-struct cds_wfs_node *__cds_wfs_pop_blocking(struct cds_wfs_stack *s)
+struct cds_wfs_node *__cds_wfs_pop_blocking(struct cds_wfs_stack *s,
+ bool *last)
{
- return ___cds_wfs_pop_blocking(s);
+ return ___cds_wfs_pop_blocking(s, last);
}
-struct cds_wfs_node *__cds_wfs_pop_nonblocking(struct cds_wfs_stack *s)
+struct cds_wfs_node *__cds_wfs_pop_nonblocking(struct cds_wfs_stack *s,
+ bool *last)
{
- return ___cds_wfs_pop_nonblocking(s);
+ return ___cds_wfs_pop_nonblocking(s, last);
}
struct cds_wfs_head *__cds_wfs_pop_all(struct cds_wfs_stack *s)
--
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com
More information about the lttng-dev
mailing list