From: Ilya Maximets <i.maximets@samsung.com>
Date: Wed, 9 Jan 2019 14:50:14 +0000 (+0300)
Subject: net/virtio: update memory ordering comment for VQ notify
X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=cc827f83595643da3b716712c2117d63752276f3;p=dpdk.git

net/virtio: update memory ordering comment for VQ notify

We're not using IO ports in case of modern device even on IA.
Also, this comment useless for other architectures.

Signed-off-by: Ilya Maximets <i.maximets@samsung.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
---

diff --git a/drivers/net/virtio/virtqueue.h b/drivers/net/virtio/virtqueue.h
index dffa03669e..53aeac238a 100644
--- a/drivers/net/virtio/virtqueue.h
+++ b/drivers/net/virtio/virtqueue.h
@@ -437,14 +437,13 @@ virtqueue_kick_prepare_packed(struct virtqueue *vq)
 	return flags != RING_EVENT_FLAGS_DISABLE;
 }
 
+/*
+ * virtqueue_kick_prepare*() or the virtio_wmb() should be called
+ * before this function to be sure that all the data is visible to vhost.
+ */
 static inline void
 virtqueue_notify(struct virtqueue *vq)
 {
-	/*
-	 * Ensure updated avail->idx is visible to host.
-	 * For virtio on IA, the notificaiton is through io port operation
-	 * which is a serialization instruction itself.
-	 */
 	VTPCI_OPS(vq->hw)->notify_queue(vq->hw, vq);
 }