Date: Thu, 25 May 2006 12:40:00 +0200 From: Gordon Bergling <gbergling@0xfce3.net> To: Max Laier <max@love2party.net> Cc: freebsd-current@freebsd.org Subject: Re: Take 2: new IP Checksum Code from DragonFlyBSD Message-ID: <20060525104000.GA4962@central.0xfce3.net> In-Reply-To: <200605250517.12054.max@love2party.net> References: <20060524180802.GA59176@central.0xfce3.net> <200605250517.12054.max@love2party.net>
next in thread | previous in thread | raw e-mail | index | archive | help
* Thus spake Max Laier (max@love2party.net): > On Wednesday 24 May 2006 20:08, Gordon Bergling wrote: > > a few month ago I ported DragonFlyBSD's IP checksum code to FreeBSD. > > My first try wasn't complete and I had forgotten it by the time. Now I > > hope I have addressed the former mistakes and it maybe included in the > > tree. ;) > > > > The patch can be found at > > http://generic.0xfce3.net/20060524-ipchecksum.patch > > > > This patch modifies the i386, amd64 and pc98 architectures. Matt Dillons > > new implementation is machine indepement, but there are some asm > > files/code with seems for me i386 centric. I don't know assembler, so I > > can't tell much about it. > > I'm a little scared about this. We have had several problems in the > checksumming code that were due to -O2 or -O0 that screwed up just a little > of the assembly and *boom* everything went downhill. I do appreciate you > stepping up porting something useful, but I'd be more comfortable if you > actually knew what you are doing. > > That said, can somebody with real assembly knowledge and maybe even for > sparc64 or the like step up and take a look at this? I think we should not > import something unless we fully understand it! > > I am confident that Matt knew what he was doing, but I am not sure that the > efforts on Dragonfly are compatible with !i386/amd64 ... FreeBSD, however > still cares about big endian architectures and others, don't we? Even if DragonFly implementation isn't compatible with archs ! i386 and derivates isn't it still an improvement on what we have now? My intention of porting it was the following comment in sys/i386/i386/in_cksum.c | * This routine is very heavily used in the network | * code and should be modified for each CPU to be as fast as | * possible. So having a better situated implementation is still an improved. The patch doesn't touch any arch !i386 and derivates, so I don't see any reason why it shouldn't be included. best regards, Gordon -- Gordon Bergling <GBergling at 0xfce3.net> http://www.0xFCE3.net/ PGP Fingerprint: 7732 9BB1 5013 AE8B E42C 28E0 93B9 D32B C76F 02A0 RIPE-HDL: MDTP-RIPE "Minimal Electronic Music"
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20060525104000.GA4962>