Consumer queue dequeuing must be guaranteed to be done fully before the tail is updated. This is not guaranteed with a read barrier, changed to a write barrier just before tail update which in practice guarantees correct order of reads and writes.
Signed-off-by: Juhamatti Kuusisaari <juhamatti.kuusisaari at coriant.com> --- lib/librte_ring/rte_ring.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/librte_ring/rte_ring.h b/lib/librte_ring/rte_ring.h index eb45e41..14920af 100644 --- a/lib/librte_ring/rte_ring.h +++ b/lib/librte_ring/rte_ring.h @@ -748,7 +748,7 @@ __rte_ring_sc_do_dequeue(struct rte_ring *r, void **obj_table, /* copy in table */ DEQUEUE_PTRS(); - rte_smp_rmb(); + rte_smp_wmb(); __RING_STAT_ADD(r, deq_success, n); r->cons.tail = cons_next; -- 2.9.0 ============================================================ The information contained in this message may be privileged and confidential and protected from disclosure. If the reader of this message is not the intended recipient, or an employee or agent responsible for delivering this message to the intended recipient, you are hereby notified that any reproduction, dissemination or distribution of this communication is strictly prohibited. If you have received this communication in error, please notify us immediately by replying to the message and deleting it from your computer. Thank you. Coriant-Tellabs ============================================================