Re: ip_summed setting for TCP pure-ACK packets

Eric Dumazet
2010-11-08T16:56:11Z

Le lundi 08 novembre 2010 à 16:35 +0000, Ben Hutchings a écrit :
> As we discussed at LPC:
>
> Current controllers handled by the sfc driver have a per-queue (rather
> than per-packet) option for checksum generation. Currently pure-ACK
> packets sent by TCP have ip_summed == CHECKSUM_NONE and we must send
> them on hardware queues with checksum generation disabled. To support
> this, we allocate 2 hardware queues per core TX queue.
>
> To reduce the risk of reordering (and possibly the number of hardware TX
> queues required), it would be helpful for TCP to set ip_summed ==
> CHECKSUM_PARTIAL on pure-ACK packets when the output device is known to
> support checksum generation.
>
> Ben.
>

Hmm

Do you mean commit 2e8e18ef52e7dd1af0a3bd1 is not enough ?