From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Subject: Re: [PATCH] Extend lock less TX to real devices Date: Sat, 4 Sep 2004 16:24:04 +0200 Sender: netdev-bounce@oss.sgi.com Message-ID: <20040904142404.GA6850@wotan.suse.de> References: <20040901223301.1a8d97a8.davem@redhat.com> <20040904132809.GB33964@muc.de> <1094307106.1634.147.camel@jzny.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Andi Kleen , "David S. Miller" , Alexey , netdev@oss.sgi.com, akepner@sgi.com Return-path: To: jamal Content-Disposition: inline In-Reply-To: <1094307106.1634.147.camel@jzny.localdomain> Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org On Sat, Sep 04, 2004 at 10:11:46AM -0400, jamal wrote: > On Sat, 2004-09-04 at 09:28, Andi Kleen wrote: > > On Wed, Sep 01, 2004 at 10:33:01PM -0700, David S. Miller wrote: > > > On Tue, 31 Aug 2004 14:38:20 +0200 > > > Andi Kleen wrote: > > > > > > > This patch extends the recently added NETIF_F_LLTX to real devices. > > > > > > Well, it does a lot of other things too. > > > > Not really, it all works to the same goal. > > Must be my sleep depravation - what is LLTX again? NETIF_F_LLTX - a new flag that tells the stack the the driver doesn't want an xmit lock. > > > > > least the user would find out in their logs. With your > > > change the system explodes looping with no explanation why. > > > > Hmm, I guess if you're really worried about this class > > of driver bugs ble eing common adding some real error handling > > for it (like bailing out and disabling the device) would > > be the far better option. > > Actually that message is pretty useful. > I have seen at least a handful of badly written drivers do that. They will still print that, no problem. > > > > patch 1) Change macros into inlines > > > patch 2) local_bh_disable() preemption count optimization > > > patch 3) support for F_LLTX on real devices > > > patch 4) locking changes > > > > At least (3) and (4) are the same thing. I can drop the > > inlines, it was only for making the code clearer and less ugly > > but is not essential for the optimizations. > > do you guys mind if i test these patches/patch out first before final > inclusion? Next weekend i will have the chance. You can do that, but they won't do much unless your driver sets NETIF_F_LLTX. -Andi