[dpdk-stable] [RFC PATCH v1 4/6] app/eventdev: add release barriers for pipeline test

[Feifei Wang <feifei.wang2@arm.com>]

Add release barriers before updating the processed packets for worker
lcores to ensure the worker lcore has really finished data processing
and then it can update the processed packets number.

Fixes: 314bcf58ca8f ("app/eventdev: add pipeline queue worker functions")
Cc: pbhagavatula@marvell.com
Cc: stable@dpdk.org

Signed-off-by: Phil Yang <phil.yang@arm.com>
Signed-off-by: Feifei Wang <feifei.wang2@arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
---
 app/test-eventdev/test_pipeline_queue.c | 64 +++++++++++++++++++++----
 1 file changed, 56 insertions(+), 8 deletions(-)

diff --git a/app/test-eventdev/test_pipeline_queue.c b/app/test-eventdev/test_pipeline_queue.c
index 7bebac34f..0c0ec0ceb 100644
--- a/app/test-eventdev/test_pipeline_queue.c
+++ b/app/test-eventdev/test_pipeline_queue.c
@@ -30,7 +30,13 @@ pipeline_queue_worker_single_stage_tx(void *arg)
 
 		if (ev.sched_type == RTE_SCHED_TYPE_ATOMIC) {
 			pipeline_event_tx(dev, port, &ev);
-			w->processed_pkts++;
+
+			/* release barrier here ensures stored operation
+			 * of the event completes before the number of
+			 * processed pkts is visible to the main core
+			 */
+			__atomic_fetch_add(&(w->processed_pkts), 1,
+					__ATOMIC_RELEASE);
 		} else {
 			ev.queue_id++;
 			pipeline_fwd_event(&ev, RTE_SCHED_TYPE_ATOMIC);
@@ -59,7 +65,13 @@ pipeline_queue_worker_single_stage_fwd(void *arg)
 		rte_event_eth_tx_adapter_txq_set(ev.mbuf, 0);
 		pipeline_fwd_event(&ev, RTE_SCHED_TYPE_ATOMIC);
 		pipeline_event_enqueue(dev, port, &ev);
-		w->processed_pkts++;
+
+		/* release barrier here ensures stored operation
+		 * of the event completes before the number of
+		 * processed pkts is visible to the main core
+		 */
+		__atomic_fetch_add(&(w->processed_pkts), 1,
+				__ATOMIC_RELEASE);
 	}
 
 	return 0;
@@ -84,7 +96,13 @@ pipeline_queue_worker_single_stage_burst_tx(void *arg)
 			if (ev[i].sched_type == RTE_SCHED_TYPE_ATOMIC) {
 				pipeline_event_tx(dev, port, &ev[i]);
 				ev[i].op = RTE_EVENT_OP_RELEASE;
-				w->processed_pkts++;
+
+				/* release barrier here ensures stored operation
+				 * of the event completes before the number of
+				 * processed pkts is visible to the main core
+				 */
+				__atomic_fetch_add(&(w->processed_pkts), 1,
+						__ATOMIC_RELEASE);
 			} else {
 				ev[i].queue_id++;
 				pipeline_fwd_event(&ev[i],
@@ -121,7 +139,13 @@ pipeline_queue_worker_single_stage_burst_fwd(void *arg)
 		}
 
 		pipeline_event_enqueue_burst(dev, port, ev, nb_rx);
-		w->processed_pkts += nb_rx;
+
+		/* release barrier here ensures stored operation
+		 * of the event completes before the number of
+		 * processed pkts is visible to the main core
+		 */
+		__atomic_fetch_add(&(w->processed_pkts), nb_rx,
+				__ATOMIC_RELEASE);
 	}
 
 	return 0;
@@ -146,7 +170,13 @@ pipeline_queue_worker_multi_stage_tx(void *arg)
 
 		if (ev.queue_id == tx_queue[ev.mbuf->port]) {
 			pipeline_event_tx(dev, port, &ev);
-			w->processed_pkts++;
+
+			/* release barrier here ensures stored operation
+			 * of the event completes before the number of
+			 * processed pkts is visible to the main core
+			 */
+			__atomic_fetch_add(&(w->processed_pkts), 1,
+					__ATOMIC_RELEASE);
 			continue;
 		}
 
@@ -180,7 +210,13 @@ pipeline_queue_worker_multi_stage_fwd(void *arg)
 			ev.queue_id = tx_queue[ev.mbuf->port];
 			rte_event_eth_tx_adapter_txq_set(ev.mbuf, 0);
 			pipeline_fwd_event(&ev, RTE_SCHED_TYPE_ATOMIC);
-			w->processed_pkts++;
+
+			/* release barrier here ensures stored operation
+			 * of the event completes before the number of
+			 * processed pkts is visible to the main core
+			 */
+			__atomic_fetch_add(&(w->processed_pkts), 1,
+					__ATOMIC_RELEASE);
 		} else {
 			ev.queue_id++;
 			pipeline_fwd_event(&ev, sched_type_list[cq_id]);
@@ -214,7 +250,13 @@ pipeline_queue_worker_multi_stage_burst_tx(void *arg)
 			if (ev[i].queue_id == tx_queue[ev[i].mbuf->port]) {
 				pipeline_event_tx(dev, port, &ev[i]);
 				ev[i].op = RTE_EVENT_OP_RELEASE;
-				w->processed_pkts++;
+
+				/* release barrier here ensures stored operation
+				 * of the event completes before the number of
+				 * processed pkts is visible to the main core
+				 */
+				__atomic_fetch_add(&(w->processed_pkts), 1,
+						__ATOMIC_RELEASE);
 				continue;
 			}
 
@@ -254,7 +296,13 @@ pipeline_queue_worker_multi_stage_burst_fwd(void *arg)
 				rte_event_eth_tx_adapter_txq_set(ev[i].mbuf, 0);
 				pipeline_fwd_event(&ev[i],
 						RTE_SCHED_TYPE_ATOMIC);
-				w->processed_pkts++;
+
+				/* release barrier here ensures stored operation
+				 * of the event completes before the number of
+				 * processed pkts is visible to the main core
+				 */
+				__atomic_fetch_add(&(w->processed_pkts), 1,
+						__ATOMIC_RELEASE);
 			} else {
 				ev[i].queue_id++;
 				pipeline_fwd_event(&ev[i],
-- 
2.17.1