d/numam-dpdk
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

vhost: remove unnecessary SMP barrier for avail idx

Browse Source 
The ordering between avail index and desc reads has been enforced
by load-acquire for split vring, so smp_rmb barrier is not needed
behind it.

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>
This commit is contained in:
Joyce Kong 2020-12-21 23:50:29 +08:00 committed by Ferruh Yigit
parent 8fc9eaaac7
commit 2d031675b2
1 changed files with 2 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
lib/librte_vhost/virtio_net.c
View File

@ -1494,13 +1494,10 @@ virtio_dev_rx_async_submit_split(struct virtio_net *dev,
struct async_inflight_info *pkts_info = vq->async_pkts_info;
int n_pkts = 0;
avail_head = __atomic_load_n(&vq->avail->idx, __ATOMIC_ACQUIRE);
/*
* The ordering between avail index and
* desc reads needs to be enforced.
* The ordering between avail index and desc reads need to be enforced.
*/
rte_smp_rmb();
avail_head = __atomic_load_n(&vq->avail->idx, __ATOMIC_ACQUIRE);
rte_prefetch0(&vq->avail->ring[vq->last_avail_idx & (vq->size - 1)]);