-----Original Message-----
> Date: Fri, 5 Oct 2018 09:44:43 +0300
> From: Andrew Rybchenko <arybche...@solarflare.com>
> To: Jerin Jacob <jerin.ja...@caviumnetworks.com>, John McNamara
> <john.mcnam...@intel.com>, Marko Kovacevic <marko.kovace...@intel.com>
> CC: dev@dpdk.org, tho...@monjalon.net, ferruh.yi...@intel.com,
> olivier.m...@6wind.com, sta...@dpdk.org
> Subject: Re: [dpdk-dev] [PATCH 1/2] doc: clarify L3 Tx checksum prerequisite
> User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101
> Thunderbird/60.0
>
> External Email
>
> On 10/5/18 7:46 AM, Jerin Jacob wrote:
>
> Based on PKT_TX_IP_CKSUM definition the user needs
> to fill l2_len and l3_len mbuf fields before issuing
> HW Tx checksum request.
>
> Fixes: dad1ec72a377 ("doc: document NIC features")
> Cc: sta...@dpdk.org<mailto:sta...@dpdk.org>
>
> Signed-off-by: Jerin Jacob
> <jerin.ja...@caviumnetworks.com><mailto:jerin.ja...@caviumnetworks.com>
>
> Acked-by: Andrew Rybchenko
> <arybche...@solarflare.com><mailto:arybche...@solarflare.com>
>
> plus one question below
>
>
> ---
>
> See PKT_TX_IP_CKSUM at
> https://git.dpdk.org/dpdk/tree/lib/librte_mbuf/rte_mbuf.h#n283
>
> ---
> doc/guides/nics/features.rst | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/doc/guides/nics/features.rst b/doc/guides/nics/features.rst
> index b085bda86..e726a6bb8 100644
> --- a/doc/guides/nics/features.rst
> +++ b/doc/guides/nics/features.rst
> @@ -562,6 +562,7 @@ Supports L3 checksum offload.
> * **[uses] rte_eth_txconf,rte_eth_txmode**:
> ``offloads:DEV_TX_OFFLOAD_IPV4_CKSUM``.
> * **[uses] mbuf**: ``mbuf.ol_flags:PKT_TX_IP_CKSUM``,
> ``mbuf.ol_flags:PKT_TX_IPV4`` | ``PKT_TX_IPV6``.
>
> Shouldn't PKT_TX_IPV6 be removed above since L3 checksum offload is not
> applicable for IPv6?
I think, some HW(What I am aware of) need to provide following[1] info in Tx
descriptors for checksum. IPV6 may be used by the HW in case, packet is
tunneled to see where inner start etc(thought it has outer_l3_len)(not strictly
from outer checksum
perspective)
[1]
- IPV4
- IPV4 with csum
- IPV6
>
>
>
> +* **[uses] mbuf**: ``mbuf.l2_len``, ``mbuf.l3_len``.
> * **[provides] mbuf**: ``mbuf.ol_flags:PKT_RX_IP_CKSUM_UNKNOWN`` |
> ``PKT_RX_IP_CKSUM_BAD`` | ``PKT_RX_IP_CKSUM_GOOD`` |
> ``PKT_RX_IP_CKSUM_NONE``.
>
>
