[PATCH v22.11] vhost: fix missing spinlock unlock

[Maxime Coquelin]

Two regressions were introduced when backporting below
patch:
b4c4e5675c85 ("vhost: fix missing lock protection in power monitor API")

First, rte_vhost_get_monitor_addr did not release the lock
in the success case. Then, rte_rwlock_read_lock() was
converted to rte_spinlock_trylock() instead of
rte_spinlock_lock().

This patch addresses both of these issues.

Fixes: a07736eb68da ("vhost: fix missing lock protection in power monitor API")
Cc: stable at dpdk.org

Signed-off-by: Maxime Coquelin <maxime.coquelin at redhat.com>
---
 lib/vhost/vhost.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/lib/vhost/vhost.c b/lib/vhost/vhost.c
index 40ac350e21..9e28198528 100644
--- a/lib/vhost/vhost.c
+++ b/lib/vhost/vhost.c
@@ -2060,6 +2060,7 @@ rte_vhost_get_monitor_addr(int vid, uint16_t queue_id,
 {
 	struct virtio_net *dev = get_device(vid);
 	struct vhost_virtqueue *vq;
+	int ret = 0;
 
 	if (dev == NULL)
 		return -1;
@@ -2070,11 +2071,12 @@ rte_vhost_get_monitor_addr(int vid, uint16_t queue_id,
 	if (vq == NULL)
 		return -1;
 
-	if (!rte_spinlock_trylock(&vq->access_lock))
-		return -1;
+	rte_spinlock_lock(&vq->access_lock);
 
-	if (unlikely(!vq->access_ok))
+	if (unlikely(!vq->access_ok)) {
+		ret = -1;
 		goto out_unlock;
+	}
 
 	if (vq_is_packed(dev)) {
 		struct vring_packed_desc *desc;
@@ -2095,12 +2097,10 @@ rte_vhost_get_monitor_addr(int vid, uint16_t queue_id,
 		pmc->match = 0;
 	}
 
-	return 0;
-
 out_unlock:
 	rte_spinlock_unlock(&vq->access_lock);
 
-	return -1;
+	return ret;
 }
 
 
-- 
2.43.0