Relax the full read barrier to one-way barrier for desc flags in
packed vring.
Signed-off-by: Joyce Kong <joyce.kong@arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
struct vring_used_elem_packed *used_elem = &vq->shadow_used_packed[0];
vq->desc_packed[vq->shadow_last_used_idx].id = used_elem->id;
- rte_smp_wmb();
- vq->desc_packed[vq->shadow_last_used_idx].flags = used_elem->flags;
+ /* desc flags is the synchronization point for virtio packed vring */
+ __atomic_store_n(&vq->desc_packed[vq->shadow_last_used_idx].flags,
+ used_elem->flags, __ATOMIC_RELEASE);
vhost_log_cache_used_vring(dev, vq, vq->shadow_last_used_idx *
sizeof(struct vring_packed_desc),