Hi Konstantin,

-----Original Message-----
From: Ananyev, Konstantin [mailto:konstantin.ananyev@intel.com]
Sent: Tuesday, January 30, 2018 12:49 AM
To: Xueming(Steven) Li <redacted>; Olivier MATZ
[off-list ref]
Cc: dev@dpdk.org; Wu, Jingjing <redacted>; Shahaf Shuler
[off-list ref]; Yongseok Koh [off-list ref]; Thomas Monjalon
[off-list ref]; Yigit, Ferruh [off-list ref]
Subject: RE: [dpdk-dev] [PATCH v2 1/5] ethdev: introduce Tx generic tunnel
offloads

Hi Xueming,

quoted

This patch introduce new TX offloads flag for devices that support
tunnel agnostic checksum and TSO offloads.

The support from the device is for inner and outer checksums on
IPV4/TCP/UDP and TSO for *any packet with the following format*:

< some headers > / [optional IPv4/IPv6] / [optional TCP/UDP] / <some
headers> / [optional inner IPv4/IPv6] / [optional TCP/UDP]

For example the following packets can use this feature:

1. eth / ipv4 / udp / VXLAN / ip / tcp 2. eth / ipv4 / GRE / MPLS /
ipv4 / udp

So in terms of usage - what is the difference with current TSO types?
Konstantin

Traditionally, HW only recognize "known" tunnel type, do TSO calculation
based on L3/L4 headers known to tunnel type. For example, it must be 
L2 header after VXLAN, then L3. While this Generic offloading provides
inner/outer L3/L4 header info(len and offset) to HW, and thus tunnel 
info become less important. Please note the MPLS over GRE tunnel in last
example above.

quoted

Signed-off-by: Xueming Li <redacted>
---
 lib/librte_ether/rte_ethdev.h | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/lib/librte_ether/rte_ethdev.h

b/lib/librte_ether/rte_ethdev.h index 1a5b4cdc5..d8d08ccb2 100644

--- a/lib/librte_ether/rte_ethdev.h
+++ b/lib/librte_ether/rte_ethdev.h

@@ -979,6 +979,16 @@ struct rte_eth_conf {
  *   the same mempool and has refcnt = 1.
  */
 #define DEV_TX_OFFLOAD_SECURITY         0x00020000
+/**< Device supports generic tunnel checksum and TSO offloading.
+ * Checksum and TSO are done based on following mbuf fields:
+ *   - Length of each header
+ *   - Type of outer/inner L3 type, IPv4 or IPv6
+ *   - Type of outer/inner L4 type, TCP or UDP.
+ *	- PKT_TX_TUNNEL_VXLAN implies outer UDP type.
+ *	- PKT_TX_TCP_SEG implies inner TCP type.
+ * Tunnel type is optional except PKT_TX_TUNNEL_VXLAN to hint outer UDP.
+ */
+#define DEV_TX_OFFLOAD_GENERIC_TNL_CKSUM_TSO	0x00040000

 /*
  * If new Tx offload capabilities are defined, they also must be
--

2.13.3