[spp] [PATCH 6/6] docs: revise explanation of usecases of spp_vf

[ogawa.yasufumi@lab.ntt.co.jp]

From: Yasufumi Ogawa <ogawa.yasufumi@lab.ntt.co.jp>

Revise explanation of usecases of spp_vf to be more understandable.

Signed-off-by: Yasufumi Ogawa <ogawa.yasufumi@lab.ntt.co.jp>
---
 docs/guides/spp_vf/gsg/setup.rst          |  2 ++
 docs/guides/spp_vf/use_cases/usecase1.rst |  4 ++-
 docs/guides/spp_vf/use_cases/usecase2.rst | 52 ++++++++++++++-----------------
 3 files changed, 29 insertions(+), 29 deletions(-)

diff --git a/docs/guides/spp_vf/gsg/setup.rst b/docs/guides/spp_vf/gsg/setup.rst
index 41c103a..9053519 100644
--- a/docs/guides/spp_vf/gsg/setup.rst
+++ b/docs/guides/spp_vf/gsg/setup.rst
@@ -162,6 +162,8 @@ PCI number is inspected
     $ sudo $RTE_SDK/usertools/dpdk-devbind.py --bind=igb_uio PCI_NUM
 
 
+.. _spp_vf_gsg_virsh_setup:
+
 virsh setup
 -----------
 
diff --git a/docs/guides/spp_vf/use_cases/usecase1.rst b/docs/guides/spp_vf/use_cases/usecase1.rst
index c6cd9e1..0c1976d 100644
--- a/docs/guides/spp_vf/use_cases/usecase1.rst
+++ b/docs/guides/spp_vf/use_cases/usecase1.rst
@@ -224,11 +224,13 @@ of targetting VM..
     spp > vf 1; classifier_table add mac 52:54:00:12:34:59 ring:5
 
 
+.. _spp_vf_use_cases_usecase1_setup_vm:
+
 Setup for VMs
 -------------
 
 Launch VM1 and VM2 with virsh command.
-Setup for virsh is described in :ref:`spp_vf_gsg_setup`.
+Setup for virsh is described in :ref:`spp_vf_gsg_virsh_setup`.
 
 .. code-block:: console
 
diff --git a/docs/guides/spp_vf/use_cases/usecase2.rst b/docs/guides/spp_vf/use_cases/usecase2.rst
index 71a8fcb..c7f62e4 100644
--- a/docs/guides/spp_vf/use_cases/usecase2.rst
+++ b/docs/guides/spp_vf/use_cases/usecase2.rst
@@ -13,7 +13,7 @@ spp_mirror.  Traffic from host2 is forwarded to each VM inside host1 thorough
 ``spp_vf``. ``spp_vf`` is required in usecase to forward traffic
 from host NIC to each VM.
 
-.. _figure_simple_mirroring:
+.. _figure_mirroring_from_vm:
 
 .. figure:: ../../images/spp_vf/spp_mirror_usecase_overview.*
    :width: 60%
@@ -21,14 +21,25 @@ from host NIC to each VM.
    Mirroring from a VM
 
 
-Launch SPP Processes
---------------------
+Network Configuration
+---------------------
 
-Move to spp directory.
+Detailed configuration of :numref:`figure_mirroring_from_vm` is described in
+:numref:`figure_spp_mirror_usecase_nwconfig`.
+In this senario, incoming packets though ``ring1`` are mirrored.
+In ``spp_mirror`` process, worker thread ``mirror1`` copies incoming packets and
+sends to orignal destination ``VM1`` and new one ``VM3``.
 
-.. code-block:: console
+.. _figure_spp_mirror_usecase_nwconfig:
 
-   $cd /path/to/spp
+.. figure:: ../../images/spp_vf/spp_mirror_usecase_nwconfig.*
+     :width: 80%
+
+     Network configuration of mirroring
+
+
+Setup SPP and VMs
+-----------------
 
 Launch ``spp-ctl`` before launching SPP primary and secondary processes.
 You also need to launch ``spp.py``  if you use ``spp_vf`` from CLI.
@@ -38,6 +49,8 @@ doing explicitly in this example to be more understandable.
 
 .. code-block:: console
 
+    $cd /path/to/spp
+
     # Launch spp-ctl and spp.py
     $ python3 ./src/spp-ctl/spp-ctl -b 127.0.0.1
     $ python ./src/spp.py -b 127.0.0.1
@@ -57,8 +70,11 @@ with ``-n 16`` for giving enough number of rings.
        -p 0x03 -n 16 -s 127.0.0.1:5555
 
 
-Then, create VM1 ``spp_vf`` and launch ``spp_vf`` with core list
-``-l 0,2-14`` in this usecase.
+Launch spp_vf
+~~~~~~~~~~~~~
+
+Launch ``VM1`` as described in :ref:`spp_vf_use_cases_usecase1_setup_vm`,
+and launch ``spp_vf`` with core list ``-l 0,2-14`` in this usecase.
 
 .. code-block:: console
 
@@ -126,26 +142,6 @@ You send packets from the remote host1 and confirm packets are received.
     $ ping 192.168.140.21
 
 
-Mirroring with spp_mirror
--------------------------
-
-The second step is starting with creating VM running with spp_mirror.
-
-Network Configuration
-~~~~~~~~~~~~~~~~~~~~~
-
-Incoming packets from NIC are forwarded to VM1 through spp_vf.
-
-Detailed configuration of :numref:`figure_simple_mirroring` is
-described below. There are two NICs on the host to send and receive packets.
-During that path, mirror component mirror1 replicates packet to merger3.
-
-.. _figure_spp_mirror_usecase_nwconfig:
-
-  .. figure:: ../../images/spp_vf/spp_mirror_usecase_nwconfig.*
-     :width: 80%
-
-     Network configuration of mirroring
 
 Launch spp_mirror
 ~~~~~~~~~~~~~~~~~
-- 
2.7.4