[PATCH 2/4] examples/ipsec-secgw: disable Tx chksum offload for inline

[Nithin Dabilpuram <ndabilpuram@marvell.com>]

Enable Tx IPv4 checksum offload only when Tx inline crypto is needed.
In other cases such as Tx Inline protocol offload, checksum computation
is implicitly taken care by HW. The advantage of having only necessary
offloads enabled is that Tx burst function can be as light as possible.

Signed-off-by: Nithin Dabilpuram <ndabilpuram@marvell.com>
---
 examples/ipsec-secgw/ipsec-secgw.c | 3 ---
 examples/ipsec-secgw/sa.c          | 9 +++++++++
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/examples/ipsec-secgw/ipsec-secgw.c b/examples/ipsec-secgw/ipsec-secgw.c
index 21abc0d..d8a9bfa 100644
--- a/examples/ipsec-secgw/ipsec-secgw.c
+++ b/examples/ipsec-secgw/ipsec-secgw.c
@@ -2314,9 +2314,6 @@ port_init(uint16_t portid, uint64_t req_rx_offloads, uint64_t req_tx_offloads)
 		local_port_conf.txmode.offloads |=
 			RTE_ETH_TX_OFFLOAD_MBUF_FAST_FREE;
 
-	if (dev_info.tx_offload_capa & RTE_ETH_TX_OFFLOAD_IPV4_CKSUM)
-		local_port_conf.txmode.offloads |= RTE_ETH_TX_OFFLOAD_IPV4_CKSUM;
-
 	printf("port %u configuring rx_offloads=0x%" PRIx64
 		", tx_offloads=0x%" PRIx64 "\n",
 		portid, local_port_conf.rxmode.offloads,
diff --git a/examples/ipsec-secgw/sa.c b/examples/ipsec-secgw/sa.c
index 1839ac7..b878a48 100644
--- a/examples/ipsec-secgw/sa.c
+++ b/examples/ipsec-secgw/sa.c
@@ -1790,6 +1790,15 @@ sa_check_offloads(uint16_t port_id, uint64_t *rx_offloads,
 				RTE_SECURITY_ACTION_TYPE_INLINE_PROTOCOL)
 				&& rule->portid == port_id) {
 			*tx_offloads |= RTE_ETH_TX_OFFLOAD_SECURITY;
+
+			/* Checksum offload is not needed for inline protocol as
+			 * all processing for Outbound IPSec packets will be
+			 * implicitly taken care and for non-IPSec packets,
+			 * there is no need of IPv4 Checksum offload.
+			 */
+			if (rule_type == RTE_SECURITY_ACTION_TYPE_INLINE_CRYPTO)
+				*tx_offloads |= RTE_ETH_TX_OFFLOAD_IPV4_CKSUM;
+
 			if (rule->mss)
 				*tx_offloads |= RTE_ETH_TX_OFFLOAD_TCP_TSO;
 		}
-- 
2.8.4