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Subject: Re: A small fix for if_em.c, if_igb.c, if_ixgbe.c
From: Adrian Chadd <adrian@freebsd.org>
To: Michael Tuexen <Michael.Tuexen@lurchi.franken.de>
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Cc: Yong-Hyeon Pyun <pyunyh@gmail.com>, Jack F Vogel <jfv@freebsd.org>,
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On 5 December 2013 13:05, Michael Tuexen
<Michael.Tuexen@lurchi.franken.de> wrote:

> Just to be clear: This would mean that xxx_transmit() would return
> an error even if the packet provided in the call xxx_transmit() is
> enqueued and not dropped?
> This would also be problem with the current SCTP stack.

I think it'll return an error only if:

* it queued the frame to the tail of the drbd;
* it then tried to transmit a frame from the head of the drbd;
* it failed to transmit the first frame in the drbd and it couldn't
put it back into the queue for whatever reason.

So I think it should be "ok enough" for both TCP and SCTP.

Give it a go and let me know how it goes.

It's an interesting architectural problem to completely solve.


-adrian