aboutsummaryrefslogtreecommitdiffhomepage
path: root/src/core/lib/support/mpscq.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/core/lib/support/mpscq.c')
-rw-r--r--src/core/lib/support/mpscq.c13
1 files changed, 12 insertions, 1 deletions
diff --git a/src/core/lib/support/mpscq.c b/src/core/lib/support/mpscq.c
index 5b9323275a..1015cc6776 100644
--- a/src/core/lib/support/mpscq.c
+++ b/src/core/lib/support/mpscq.c
@@ -54,21 +54,31 @@ void gpr_mpscq_push(gpr_mpscq *q, gpr_mpscq_node *n) {
}
gpr_mpscq_node *gpr_mpscq_pop(gpr_mpscq *q) {
+ bool empty;
+ return gpr_mpscq_pop_and_check_end(q, &empty);
+}
+
+gpr_mpscq_node *gpr_mpscq_pop_and_check_end(gpr_mpscq *q, bool *empty) {
gpr_mpscq_node *tail = q->tail;
gpr_mpscq_node *next = (gpr_mpscq_node *)gpr_atm_acq_load(&tail->next);
if (tail == &q->stub) {
// indicates the list is actually (ephemerally) empty
- if (next == NULL) return NULL;
+ if (next == NULL) {
+ *empty = true;
+ return NULL;
+ }
q->tail = next;
tail = next;
next = (gpr_mpscq_node *)gpr_atm_acq_load(&tail->next);
}
if (next != NULL) {
+ *empty = false;
q->tail = next;
return tail;
}
gpr_mpscq_node *head = (gpr_mpscq_node *)gpr_atm_acq_load(&q->head);
if (tail != head) {
+ *empty = false;
// indicates a retry is in order: we're still adding
return NULL;
}
@@ -79,5 +89,6 @@ gpr_mpscq_node *gpr_mpscq_pop(gpr_mpscq *q) {
return tail;
}
// indicates a retry is in order: we're still adding
+ *empty = false;
return NULL;
}