> > An alternative might be to come up with something decent and target 2.6.24.x
I don't see mmiotrace getting merged into a stable kernel... how do however see it getting cleaned up for 2.6.25 now that people know how fragile the kernel hooks for it are.. > We put the crappy code back in for 2.6.24 then take it out immediately > after 2.6.24 and put something else in to support mmiotrace and perhaps the > other new mystery features to which you refer below. hm. (I think the other mystery feature is actually a Novell kernel debugger but I'm not sure, madwifi use it for similiar reasons to mmiotrace I think..) > > > all that crap > > > } > > > > > > > > > But that's all speculation. Has anyone actually measured the pagefault > > > latency impact of this change? Message-Id: <[EMAIL PROTECTED]> Subject: [patch 20/38] Minor fault path optimization. Date: Fri, 27 Apr 2007 16:05:23 +0200 was a patch to do exactly that.. hch decided the feature wasn't useful and posted a patch to remove it.. > > That change has been in the mainline tree for nearly three months. All > these affected parties have left it until the eve of 2.6.24 to actually > tell us about it. This is causing me sympathy problems :( > Jan first complained on the 4th Decemeber last year, I'm just posting this now because Linus said send him a patch to revert regressions rather than just complain, I've prepared the patch to put back the old behaviour from 2.6.23. This was only brought to my notice this morning but I'm not going to let that stop me from trying to find a correct fix rather than just ripping the feature out.. I think we could apply the page fault cleanup patch I mentioned earlier on top of this patch and get back the 300 cycles and that would make people happy, it makes sense for mmiotrace to use kprobes hooks and not have to do this stuff directly but if that is what is wanted the mmiotrace guys can do it directly in the future. Dave. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
