DPDK patches and discussions
 help / color / mirror / Atom feed
From: Marvin Liu <yong.liu@intel.com>
To: maxime.coquelin@redhat.com, tiwei.bie@intel.com
Cc: zhihong.wang@intel.com, dev@dpdk.org, Marvin Liu <yong.liu@intel.com>
Subject: [dpdk-dev] [PATCH v4 1/9] vhost: advertise support in-order feature
Date: Sun,  1 Jul 2018 07:50:41 +0800	[thread overview]
Message-ID: <20180630235049.62610-2-yong.liu@intel.com> (raw)
In-Reply-To: <20180630235049.62610-1-yong.liu@intel.com>

If devices always use descriptors in the same order in which they have
been made available. These devices can offer the VIRTIO_F_IN_ORDER
feature. If negotiated, this knowledge allows devices to notify the use
of a batch of buffers to virtio driver by only writing used ring index.

Vhost user device has supported this feature by default. If vhost
dequeue zero is enabled, should disable VIRTIO_F_IN_ORDER as vhost can’t
assure that descriptors returned from NIC are in order.

Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

diff --git a/lib/librte_vhost/socket.c b/lib/librte_vhost/socket.c
index 0399c37bc..d63031747 100644
--- a/lib/librte_vhost/socket.c
+++ b/lib/librte_vhost/socket.c
@@ -853,6 +853,12 @@ rte_vhost_driver_register(const char *path, uint64_t flags)
 	vsocket->supported_features = VIRTIO_NET_SUPPORTED_FEATURES;
 	vsocket->features           = VIRTIO_NET_SUPPORTED_FEATURES;
 
+	/* Dequeue zero copy can't assure descriptors returned in order */
+	if (vsocket->dequeue_zero_copy) {
+		vsocket->supported_features &= ~(1ULL << VIRTIO_F_IN_ORDER);
+		vsocket->features &= ~(1ULL << VIRTIO_F_IN_ORDER);
+	}
+
 	if (!(flags & RTE_VHOST_USER_IOMMU_SUPPORT)) {
 		vsocket->supported_features &= ~(1ULL << VIRTIO_F_IOMMU_PLATFORM);
 		vsocket->features &= ~(1ULL << VIRTIO_F_IOMMU_PLATFORM);
diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
index 786a74f64..3437b996b 100644
--- a/lib/librte_vhost/vhost.h
+++ b/lib/librte_vhost/vhost.h
@@ -191,6 +191,13 @@ struct vhost_msg {
  #define VIRTIO_F_VERSION_1 32
 #endif
 
+/*
+ * Available and used descs are in same order
+ */
+#ifndef VIRTIO_F_IN_ORDER
+#define VIRTIO_F_IN_ORDER      35
+#endif
+
 /* Features supported by this builtin vhost-user net driver. */
 #define VIRTIO_NET_SUPPORTED_FEATURES ((1ULL << VIRTIO_NET_F_MRG_RXBUF) | \
 				(1ULL << VIRTIO_F_ANY_LAYOUT) | \
@@ -214,7 +221,8 @@ struct vhost_msg {
 				(1ULL << VIRTIO_NET_F_GUEST_ECN) | \
 				(1ULL << VIRTIO_RING_F_INDIRECT_DESC) | \
 				(1ULL << VIRTIO_RING_F_EVENT_IDX) | \
-				(1ULL << VIRTIO_NET_F_MTU) | \
+				(1ULL << VIRTIO_NET_F_MTU)  | \
+				(1ULL << VIRTIO_F_IN_ORDER) | \
 				(1ULL << VIRTIO_F_IOMMU_PLATFORM))
 
 
-- 
2.17.0

  reply	other threads:[~2018-06-30 16:05 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-06-30 23:50 [dpdk-dev] [PATCH v4 0/9] " Marvin Liu
2018-06-30 23:50 ` Marvin Liu [this message]
2018-06-30 23:50 ` [dpdk-dev] [PATCH v4 2/9] net/virtio: add in-order feature bit definition Marvin Liu
2018-06-30 23:50 ` [dpdk-dev] [PATCH v4 3/9] net/virtio-user: add unsupported features mask Marvin Liu
2018-06-30 23:50 ` [dpdk-dev] [PATCH v4 4/9] net/virtio-user: add mrg-rxbuf and in-order vdev parameters Marvin Liu
2018-06-30 23:50 ` [dpdk-dev] [PATCH v4 5/9] net/virtio: free in-order descriptors before device start Marvin Liu
2018-07-02  7:18   ` Maxime Coquelin
2018-06-30 23:50 ` [dpdk-dev] [PATCH v4 6/9] net/virtio: extract common part for in-order functions Marvin Liu
2018-06-30 23:50 ` [dpdk-dev] [PATCH v4 7/9] net/virtio: support in-order Rx and Tx Marvin Liu
2018-06-30 23:50 ` [dpdk-dev] [PATCH v4 8/9] net/virtio: add in-order Rx/Tx into selection Marvin Liu
2018-06-30 23:50 ` [dpdk-dev] [PATCH v4 9/9] net/virtio: advertise support in-order feature Marvin Liu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20180630235049.62610-2-yong.liu@intel.com \
    --to=yong.liu@intel.com \
    --cc=dev@dpdk.org \
    --cc=maxime.coquelin@redhat.com \
    --cc=tiwei.bie@intel.com \
    --cc=zhihong.wang@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).