Hi Gavin,
On 1/10/19 9:19 AM, Gavin Hu (Arm Technology China) wrote:
-----Original Message-----
From: dev <[email protected]> On Behalf Of Ilya Maximets
Sent: Wednesday, January 9, 2019 10:50 PM
To: [email protected]; Maxime Coquelin <[email protected]>;
Michael S . Tsirkin <[email protected]>; Xiao Wang
<[email protected]>
Cc: Tiwei Bie <[email protected]>; Zhihong Wang
<[email protected]>; [email protected]; Jason Wang
<[email protected]>; [email protected];
[email protected]; Ilya Maximets
<[email protected]>
Subject: [dpdk-dev] [PATCH v3 2/3] 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.
Agree, it should be architecture neutral.
Signed-off-by: Ilya Maximets <[email protected]>
---
drivers/net/virtio/virtqueue.h | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/drivers/net/virtio/virtqueue.h b/drivers/net/virtio/virtqueue.h
index dffa03669..53aeac238 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.
+ */
C11 _atomic APIs are preferred for new code, other than wmb or rmb, could you
work on that?
Thanks for the review.
-rc2 deadline is today, so I may apply this series as is if no reply
from Ilya today. If a change is agreed, it could be made on top for
-rc3.
Regards,
Maxime
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);
}
--
2.17.1
