* Generating fragmented skb
@ 2013-11-06 12:31 David Laight
2013-11-06 19:01 ` Ben Hutchings
0 siblings, 1 reply; 2+ messages in thread
From: David Laight @ 2013-11-06 12:31 UTC (permalink / raw)
To: netdev
What is the easiest way to generate fragmented skb?
I'm trying to test the xhci USB bulk code using a couple
of USB ethernet devices (smsc95xx and ax88179_178a).
I think the latter should support TCP segmentation offload.
FWIW some tests that seemed to imply the ax88179_178a needed
the ZLP avoidance code may have been caused because the
xhci driver completely ignored USB_ZETO_PACKET.
David
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: Generating fragmented skb
2013-11-06 12:31 Generating fragmented skb David Laight
@ 2013-11-06 19:01 ` Ben Hutchings
0 siblings, 0 replies; 2+ messages in thread
From: Ben Hutchings @ 2013-11-06 19:01 UTC (permalink / raw)
To: David Laight; +Cc: netdev
On Wed, 2013-11-06 at 12:31 +0000, David Laight wrote:
> What is the easiest way to generate fragmented skb?
[...]
TCP usually generates fragmented skbs when the output device supports
them, separating the payload (may be transmitted multiple times, not
modified by the stack) from the headers (regenerated by the stack for
each transmission). For small sends this is no longer the case.
You can use sendfile() to control fragmentation from userland.
Ben.
--
Ben Hutchings, Staff Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2013-11-06 19:02 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-11-06 12:31 Generating fragmented skb David Laight
2013-11-06 19:01 ` Ben Hutchings
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox