sowmini.varadhan at sun.com wrote:
> To follow up on the code review comment about checksum offload:
>
> I verified with the NIC-China team and received the following information
> from Ted You:
>
> The bge driver hardware checksum offload itself doesn't have any
> problems. I think the purpose of this private property is for
> possible debugging in the future.
>
> The hardware checksum is enabled by default by the Broadcom
> chipset hardware, it cannot be disabled by the driver. And those bits
> will be set in every hw_rbd when receiving packets. If we want to
> hide the rx hardware checksum, the only way is to add the
> conditionals to check the flag and bypass the processing of those
> hw_rbd bits. So if we keep this private property, we cannot avoid
> such code in the hot code path. It's likely that the extra check does not
> have a significant impact on performance.
>
> Since the code has been added for debugging purposes only (to debug
> problems like data corruption, hw workaround etc.) we will remove the
> changes related to bge_chksum_flag and add them back later after verifying
> that there is no impact on performance.
>
> One possibility is to provide support for this in DEBUG kernels only.
> I've filed a place-holder RFE to track this: see CR 6629075.
>
I think using it in DEBUG kernels is fine. Although, unless someone has
specifically requested it, I probably wouldn't even bother doing that.
Thanks for tracking this down.
-- Garrett
