iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

virtio_ring: add unlikely annotation for free descs check

Browse Source 
The 'if (vq->vq.num_free < descs_used)' check will almost always be false.

Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com>
Message-Id: <20220328105817.1028065-2-xianting.tian@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
This commit is contained in:
Xianting Tian 2022-03-28 18:58:17 +08:00 committed by Michael S. Tsirkin
parent 35c51e093d
commit b4b4ff73ef
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/virtio/virtio_ring.c
View File

@ -517,7 +517,7 @@ static inline int virtqueue_add_split(struct virtqueue *_vq,
descs_used = total_sg;
}
if (vq->vq.num_free < descs_used) {
if (unlikely(vq->vq.num_free < descs_used)) {
pr_debug("Can't add buf len %i - avail = %i\n",
descs_used, vq->vq.num_free);
/* FIXME: for historical reasons, we force a notify here if