[RFC,3/5] vhost: fix async access
Commit Message
vq->async is protected with vq->access_lock.
Fixes: eb666d24085f ("vhost: fix async unregister deadlock")
Fixes: 0c0935c5f794 ("vhost: allow to check in-flight packets for async vhost")
Cc: stable@dpdk.org
Signed-off-by: David Marchand <david.marchand@redhat.com>
---
This has been reported by Jiayu too:
https://patchwork.dpdk.org/project/dpdk/patch/20220328020754.1155063-1-jiayu.hu@intel.com/
---
lib/vhost/vhost.c | 25 ++++++++++---------------
1 file changed, 10 insertions(+), 15 deletions(-)
@@ -1753,27 +1753,23 @@ rte_vhost_async_channel_unregister(int vid, uint16_t queue_id)
if (vq == NULL)
return ret;
- ret = 0;
-
- if (!vq->async)
- return ret;
-
if (vhost_spinlock_trylock(&vq->access_lock) == 0) {
VHOST_LOG_CONFIG(ERR, "(%s) failed to unregister async channel, virtqueue busy.\n",
dev->ifname);
- return -1;
+ return ret;
}
- if (vq->async->pkts_inflight_n) {
+ if (!vq->async) {
+ ret = 0;
+ } else if (vq->async->pkts_inflight_n) {
VHOST_LOG_CONFIG(ERR, "(%s) failed to unregister async channel.\n", dev->ifname);
VHOST_LOG_CONFIG(ERR, "(%s) inflight packets must be completed before unregistration.\n",
dev->ifname);
- ret = -1;
- goto out;
+ } else {
+ vhost_free_async_mem(vq);
+ ret = 0;
}
- vhost_free_async_mem(vq);
-out:
vhost_spinlock_unlock(&vq->access_lock);
return ret;
@@ -1891,9 +1887,6 @@ rte_vhost_async_get_inflight(int vid, uint16_t queue_id)
if (vq == NULL)
return ret;
- if (!vq->async)
- return ret;
-
if (vhost_spinlock_trylock(&vq->access_lock) == 0) {
VHOST_LOG_CONFIG(DEBUG,
"(%s) failed to check in-flight packets. virtqueue busy.\n",
@@ -1901,7 +1894,9 @@ rte_vhost_async_get_inflight(int vid, uint16_t queue_id)
return ret;
}
- ret = vq->async->pkts_inflight_n;
+ if (vq->async)
+ ret = vq->async->pkts_inflight_n;
+
vhost_spinlock_unlock(&vq->access_lock);
return ret;