From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: txqueuelen has wrong units; should be time
Date: Tue, 01 Mar 2011 06:36:58 +0100
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Cc: John Heffner <johnwheffner@gmail.com>,
	"John W. Linville" <linville@tuxdriver.com>,
	Jussi Kivilinna <jussi.kivilinna@mbnet.fi>,
	Mikael Abrahamsson <swmike@swm.pp.se>,
	linux-kernel <linux-kernel@vger.kernel.org>,
	netdev@vger.kernel.org
To: Albert Cahalan <acahalan@gmail.com>
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Le mardi 01 mars 2011 =C3=A0 06:01 +0100, Eric Dumazet a =C3=A9crit :
> Le lundi 28 f=C3=A9vrier 2011 =C3=A0 23:11 -0500, Albert Cahalan a =C3=
=A9crit :
>=20
> > It sounds like you need a callback or similar, so that TCP can be
> > informed later that the drop has occurred.
>=20
> There is the thing called skb destructor / skb_orphan() mess, that is
> not stackable... Might extend this to something more clever, and be a=
ble
> to call functions (into TCP stack for example) giving a status of skb=
 :
> Sent, or dropped somewhere in the stack...
>=20

One problem of such schem is the huge extra cost involved, extra
locking, extra memory allocations, extra atomic operations...