From: Joyce Kong <joyce.kong@arm.com>
Date: Mon, 21 Dec 2020 15:50:27 +0000 (+0800)
Subject: examples/vhost_blk: replace SMP barrier with thread fence
X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=96d1d898dcbc4319d8416b222aa6ba081e605823;p=dpdk.git

examples/vhost_blk: replace SMP barrier with thread fence

Simply replace the rte_smp_mb barriers with SEQ_CST atomic thread fence,
if there is no load/store operations.

Signed-off-by: Joyce Kong <joyce.kong@arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
---

diff --git a/examples/vhost_blk/vhost_blk.c b/examples/vhost_blk/vhost_blk.c
index bb293d492f..7ea60863da 100644
--- a/examples/vhost_blk/vhost_blk.c
+++ b/examples/vhost_blk/vhost_blk.c
@@ -86,9 +86,9 @@ enqueue_task(struct vhost_blk_task *task)
 	 */
 	used->ring[used->idx & (vq->vring.size - 1)].id = task->req_idx;
 	used->ring[used->idx & (vq->vring.size - 1)].len = task->data_len;
-	rte_smp_mb();
+	rte_atomic_thread_fence(__ATOMIC_SEQ_CST);
 	used->idx++;
-	rte_smp_mb();
+	rte_atomic_thread_fence(__ATOMIC_SEQ_CST);
 
 	rte_vhost_clr_inflight_desc_split(task->ctrlr->vid,
 		vq->id, used->idx, task->req_idx);
@@ -112,12 +112,12 @@ enqueue_task_packed(struct vhost_blk_task *task)
 	desc->id = task->buffer_id;
 	desc->addr = 0;
 
-	rte_smp_mb();
+	rte_atomic_thread_fence(__ATOMIC_SEQ_CST);
 	if (vq->used_wrap_counter)
 		desc->flags |= VIRTQ_DESC_F_AVAIL | VIRTQ_DESC_F_USED;
 	else
 		desc->flags &= ~(VIRTQ_DESC_F_AVAIL | VIRTQ_DESC_F_USED);
-	rte_smp_mb();
+	rte_atomic_thread_fence(__ATOMIC_SEQ_CST);
 
 	rte_vhost_clr_inflight_desc_packed(task->ctrlr->vid, vq->id,
 					   task->inflight_idx);