> -----Original Message-----
> From: David Marchand <david.march...@redhat.com>
> Sent: Tuesday, February 2, 2021 17:45
> To: Wang, Haiyue <haiyue.w...@intel.com>
> Cc: dev <dev@dpdk.org>; pvale...@redhat.com; Aaron Conole
> <acon...@redhat.com>; Zhang, Qi Z
> <qi.z.zh...@intel.com>; Rong, Leyi <leyi.r...@intel.com>; Tu, Lijuan
> <lijuan...@intel.com>; dpdk
> stable <sta...@dpdk.org>; Guo, Jia <jia....@intel.com>; Richardson, Bruce
> <bruce.richard...@intel.com>;
> Ananyev, Konstantin <konstantin.anan...@intel.com>; Jerin Jacob Kollanukkaran
> <jer...@marvell.com>;
> Ruifeng Wang (Arm Technology China) <ruifeng.w...@arm.com>
> Subject: Re: [PATCH v1] net/ixgbe: adjust error for UDP with zero checksum
>
>
> If the driver/hw can't report a valid checksum hint, it should
> announce it does not know if the checksum is valid (neither bad, nor
> good).
>
> So the workaround for udp packets (on this hw model) would be to
> report PKT_RX_L4_CKSUM_UNKNOWN.
> The sw application will then have to recompute the checksum itself if needed.
>
Looks like this workaround will make OVS performance drop a lot, since
every UDP packet needs to do checksum by SW:
bool hwol_good_l4_csum = dp_packet_l4_checksum_valid(pkt)
|| dp_packet_hwol_tx_l4_checksum(pkt);
/* Validate the checksum only when hwol is not supported. */
if (extract_l4(&ctx->key, l4, dp_packet_l4_size(pkt),
&ctx->icmp_related, l3, !hwol_good_l4_csum,
NULL)) {
ctx->hash = conn_key_hash(&ctx->key, ct->hash_basis);
return true;
}
The lesser of the two rights, marking as good seems a little better.
>
> --
> David Marchand
