[dpdk-dev,v3] doc: add limitations for i40e PMD
Commit Message
This patch adds "Limitations or Known issues" section for
i40e PMD, including two items:
1. MPLS packet classification on X710/XL710
2. 16 Byte Descriptor cannot be used on DPDK VF
3. Link down with i40e kernel driver after DPDK application exist
Signed-off-by: Jingjing Wu <jingjing.wu@intel.com>
---
v2 changes:
fix typo.
v3 changes:
add one more limitation.
rewording.
doc/guides/nics/i40e.rst | 42 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 42 insertions(+)
Comments
> -----Original Message-----
> From: Wu, Jingjing
> Sent: Friday, September 30, 2016 7:46 AM
> To: dev@dpdk.org
> Cc: Wu, Jingjing <jingjing.wu@intel.com>; Xing, Beilei
> <beilei.xing@intel.com>; Mcnamara, John <john.mcnamara@intel.com>
> Subject: [PATCH v3] doc: add limitations for i40e PMD
>
> This patch adds "Limitations or Known issues" section for i40e PMD,
> including two items:
> 1. MPLS packet classification on X710/XL710 2. 16 Byte Descriptor cannot
> be used on DPDK VF 3. Link down with i40e kernel driver after DPDK
> application exist
>
> Signed-off-by: Jingjing Wu <jingjing.wu@intel.com>
Acked-by: John McNamara <john.mcnamara@intel.com>
On Fri, Sep 30, 2016 at 03:09:53PM +0000, Mcnamara, John wrote:
>
>
> > -----Original Message-----
> > From: Wu, Jingjing
> > Sent: Friday, September 30, 2016 7:46 AM
> > To: dev@dpdk.org
> > Cc: Wu, Jingjing <jingjing.wu@intel.com>; Xing, Beilei
> > <beilei.xing@intel.com>; Mcnamara, John <john.mcnamara@intel.com>
> > Subject: [PATCH v3] doc: add limitations for i40e PMD
> >
> > This patch adds "Limitations or Known issues" section for i40e PMD,
> > including two items:
> > 1. MPLS packet classification on X710/XL710 2. 16 Byte Descriptor cannot
> > be used on DPDK VF 3. Link down with i40e kernel driver after DPDK
> > application exist
> >
> > Signed-off-by: Jingjing Wu <jingjing.wu@intel.com>
>
>
> Acked-by: John McNamara <john.mcnamara@intel.com>
>
Applied to dpdk-next-net/rel_16_11
/Bruce
@@ -411,3 +411,45 @@ configuration passed on the EAL command line.
The floating VEB functionality requires a NIC firmware version of 5.0
or greater.
+
+
+Limitations or Known issues
+---------------------------
+
+MPLS packet classification on X710/XL710
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+For firmware versions prior to 5.0, MPLS packets are not recognized by the NIC.
+The L2 Payload flow type in flow director can be used to classify MPLS packet
+by using a command in testpmd like:
+
+ testpmd> flow_director_filter 0 mode IP add flow l2_payload ether \
+ 0x8847 flexbytes () fwd pf queue <N> fd_id <M>
+
+With the NIC firmware version 5.0 or greater, some limited MPLS support
+is added: Native MPLS (MPLS in Ethernet) skip is implemented, while no
+new packet type, no classification or offload are possible. With this change,
+L2 Payload flow type in flow director cannot be used to classify MPLS packet
+as with previous firmware versions. Meanwhile, the Ethertype filter can be
+used to classify MPLS packet by using a command in testpmd like:
+
+ testpmd> ethertype_filter 0 add mac_ignr 00:00:00:00:00:00 ethertype \
+ 0x8847 fwd queue <M>
+
+16 Byte Descriptor cannot be used on DPDK VF
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+If the Linux i40e kernel driver is used as host driver, while DPDK i40e PMD
+is used as the VF driver, DPDK cannot choose 16 byte receive descriptor. That
+is to say, user should keep ``CONFIG_RTE_LIBRTE_I40E_16BYTE_RX_DESC=n`` in
+config file.
+
+Link down with i40e kernel driver after DPDK application exist
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+After DPDK application quit, and the device is bound back to Linux i40e
+kernel driver, the link cannot be up after ``ifconfig <dev> up``.
+To work around this issue, ``ethtool -s <dev> autoneg on`` should be
+set first and then the link can be brought up through ``ifconfig <dev> up``.
+
+NOTE: requires Linux kernel i40e driver version >= 1.4.X