From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 11 May 2001 06:23:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 11 May 2001 06:23:30 -0400 Received: from zikova.cvut.cz ([147.32.235.100]:32014 "EHLO zikova.cvut.cz") by vger.kernel.org with ESMTP id ; Fri, 11 May 2001 06:23:21 -0400 From: "Petr Vandrovec" Organization: CC CTU Prague To: Andi Kleen Date: Fri, 11 May 2001 12:21:59 MET-1 MIME-Version: 1.0 Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7BIT Subject: Re: Source code compatibility in Stable series???? CC: Rogier Wolff , linux-kernel@vger.kernel.org, davem@redhat.com X-mailer: Pegasus Mail v3.40 Message-ID: <2983F527D00@vcnet.vc.cvut.cz> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On 11 May 01 at 12:03, Andi Kleen wrote: > On Fri, May 11, 2001 at 02:56:35AM -0700, David S. Miller wrote: > I guess it would be possible to add a HAVE_ZEROCOPY to skbuff.h to make > it a bit easier for single source drivers. > > --- include/linux/skbuff.h-o Wed May 9 12:36:44 2001 > +++ include/linux/skbuff.h Fri May 11 12:12:43 2001 > @@ -29,6 +29,7 @@ > #define HAVE_ALLOC_SKB /* For the drivers to know */ > #define HAVE_ALIGNABLE_SKB /* Ditto 8) */ > #define SLAB_SKB /* Slabified skbuffs */ > +#define HAVE_ZEROCOPY /* Zerocopy stack */ When I was updating VMware's vmnet, I decided to use #ifdef skb_shinfo This gives you maximal backward compatibility, as all public zerocopy patches contain this macro. Only thing is that Dave has to remember that when he turns skb_shinfo into inline function, an identity #define have to be added. Just my opinion - as you cannot add HAVE_ZEROCOPY to all already existing and installed kernels. Petr Vandrovec vandrove@vc.cvut.cz