svn commit: r207851 - head/sys/dev/sge

[Bjoern A. Zeeb]

On Tue, 18 May 2010, Pyun YongHyeon wrote:

> On Tue, May 18, 2010 at 10:53:27PM +0000, Bjoern A. Zeeb wrote:
>> On Tue, 18 May 2010, Pyun YongHyeon wrote:
>>
>>> On Tue, May 18, 2010 at 03:27:33AM +0000, Bjoern A. Zeeb wrote:
>>>> On Mon, 10 May 2010, Pyun YongHyeon wrote:
>>>>
>>>>> Author: yongari
>>>>> Date: Mon May 10 17:14:14 2010
>>>>> New Revision: 207851
>>>>> URL: http://svn.freebsd.org/changeset/base/207851
>>>>>
>>>>> Log:
>>>>> Implement TSO and TSO over VLAN. Increase number of allowed
>>>>> fragmentation of mbuf chain to 32 from 16 because TSO can send 64KB
>>>>> sized packet which in turn requires long list of mbuf chain. Due to
>>>>> lack of documentation, I'm not sure whether driver have to pull up
>>>>> ethernet/IP/TCP header with options to make controller work but
>>>>> driver have to parse TCP header to update pseudo TCP checksum
>>>>> anyway. The controller expects pseudo TCP checksum computed by
>>>>> upper stack and the checksum should follow the MS NDIS
>>>>> specification to make TSO work.
>>>>>
>>>>> Tested by:	xclin <xclin <> cs dot nctu dot edu dot tw >
>>>>
>>>> This brings in INET as a dependency for the driver and fails on my
>>>> 	nooptions INET
>>>> 	nooptions INET6
>>>> kernels (in_pseudo()).
>>>>
>>>
>>> AFAIK sge(4) is not the only driver that has INET dependency. I
>>> think we need IPv6 offloading framework(checksum offloading, TSO4
>>
>> There is no checksum on IPv6.
>>
>
> Yes, but controllers that computes only partial checksum for
> received frames require parsing IPv4/IPv6 header to support
> checksum offloading. If we have good framework we can avoid
> duplicated code as well as INET/INET6 dependency.
>
>>> and TSO6) before removing INET dependency in various drivers.
>>> Most recent ethernet controllers support IPv6 offloading and
>>> FreeBSD still lacks these nice features.
>>
>> This is true, but we should (still) fix this and work on a better
>> solution.  You may remember that I tried to get this discussion
>> started twice during the last 12 months.  First time after I added
>> the inet depency in sys/conf/files for all the other drivers that
>> have the same problem(s).
>>
>> I will be very happy to chat with you and np@ and maybe tuexen@ for
>> SCTP and Drew and Jack again to get this all sorted out.
>>
>
> I'm also happy to go that direction.

Great!

> But it wouldn't be for 8.1-RELEASE, right?

Right.

-- 
Bjoern A. Zeeb                                     (from 21) Micky Rosa:
    But as we've all said, this game is about the past and the future,
    and tonight we forget about the past. We just focus on the future.