New upstream version 18.08

[deb_dpdk.git] / doc / guides / nics / virtio.rst

diff --git a/doc/guides/nics/virtio.rst b/doc/guides/nics/virtio.rst
index ca09cd2..7c099fb 100644 (file)
--- a/doc/guides/nics/virtio.rst
+++ b/doc/guides/nics/virtio.rst
@@ -201,7 +201,7 @@ The packet transmission flow is:
 Virtio PMD Rx/Tx Callbacks
 --------------------------
 
-Virtio driver has 3 Rx callbacks and 2 Tx callbacks.
+Virtio driver has 4 Rx callbacks and 3 Tx callbacks.
 
 Rx callbacks:
 
@@ -215,6 +215,9 @@ Rx callbacks:
    Vector version without mergeable Rx buffer support, also fixes the available
    ring indexes and uses vector instructions to optimize performance.
 
+#. ``virtio_recv_mergeable_pkts_inorder``:
+   In-order version with mergeable Rx buffer support.
+
 Tx callbacks:
 
 #. ``virtio_xmit_pkts``:
@@ -223,6 +226,8 @@ Tx callbacks:
 #. ``virtio_xmit_pkts_simple``:
    Vector version fixes the available ring indexes to optimize performance.
 
+#. ``virtio_xmit_pkts_inorder``:
+   In-order version.
 
 By default, the non-vector callbacks are used:
 
@@ -234,7 +239,7 @@ By default, the non-vector callbacks are used:
 
 Vector callbacks will be used when:
 
-*   ``txq_flags`` is set to ``VIRTIO_SIMPLE_FLAGS`` (0xF01), which implies:
+*   ``txmode.offloads`` is set to ``0x0``, which implies:
 
     *   Single segment is specified.
 
@@ -252,8 +257,14 @@ The corresponding callbacks are:
 Example of using the vector version of the virtio poll mode driver in
 ``testpmd``::
 
-   testpmd -l 0-2 -n 4 -- -i --txqflags=0xF01 --rxq=1 --txq=1 --nb-cores=1
+   testpmd -l 0-2 -n 4 -- -i --tx-offloads=0x0 --rxq=1 --txq=1 --nb-cores=1
+
+In-order callbacks only work on simulated virtio user vdev.
+
+*   For Rx: If mergeable Rx buffers is enabled and in-order is enabled then
+    ``virtio_xmit_pkts_inorder`` is used.
 
+*   For Tx: If in-order is enabled then ``virtio_xmit_pkts_inorder`` is used.
 
 Interrupt mode
 --------------
@@ -318,3 +329,26 @@ Here we use l3fwd-power as an example to show how to get started.
 
         $ l3fwd-power -l 0-1 -- -p 1 -P --config="(0,0,1)" \
                                                --no-numa --parse-ptype
+
+
+Virtio PMD arguments
+--------------------
+
+The user can specify below argument in devargs.
+
+#.  ``vdpa``:
+
+    A virtio device could also be driven by vDPA (vhost data path acceleration)
+    driver, and works as a HW vhost backend. This argument is used to specify
+    a virtio device needs to work in vDPA mode.
+    (Default: 0 (disabled))
+
+#. ``mrg_rxbuf``:
+
+    It is used to enable virtio device mergeable Rx buffer feature.
+    (Default: 1 (enabled))
+
+#. ``in_order``:
+
+    It is used to enable virtio device in-order feature.
+    (Default: 1 (enabled))