On 03/26/2012 06:21 PM, Ingo Molnar wrote: > * Avi Kivity <avi@xxxxxxxxxx> wrote: > > > Say a fix comes in which needs to be mainlined during -rc. So > > I put it in some other branch, to be sent off to Linus in a > > few days after maturing a little. Meanwhile developers see an > > incomplete tree, since that patch is not in it. > > > > Once Linus pulls, I can merge it back (or even before, if I'm > > reasonably certain it's not going to change), but it leaves a > > history of unneeded merges. Or we can do throwaway merges > > like tip.git. > > We don't do throwaway merges in the -tip development branches > themselves, i.e. in tip:sched/core, tip:perf/core, > tip:timers/core, etc. > > When a fix goes into tip:sched/urgent then until Linus merges it > it's not in tip:sched/core. 99% of the fixes don't *have to* go > into sched/core straight away. > > In the odd case where there's some dependency, we can manually > merge it into tip:sched/core ahead of Linus pulling into an -rc. > Those rare merges are not a problem, and I explain the reason in > the merge commit itself. > > If you look at: > > gll v3.2..v3.3 | grep -E '/urgent.*/core' > > you'll see that I only had to do it once in the previous cycle: > > d6c1c49de577 Merge branch 'perf/urgent' into perf/core > > and the changelog explains the background: > > Merge reason: Add these cherry-picked commits so that future changes > on perf/core don't conflict. > > it was a rare, oddball situation where we cherry-picked > perf/core changes into perf/urgent. Extra merges are perfectly > fine in that case. > > The 'throwaway' tip:master branch you are probably referring to > is basically just a testing branch, a convenient merged tree of > the one dozen maintainer trees that are hosted in -tip. Since we > don't want to force Linus's hand of him being able to reject > individual trees we don't merge them properly - hence the > integrated tree is a throwaway tree in theory. > > In practice I tend to throw it away only once per cycle, around > -rc1, once all pending trees went to Linus. tip:master is not > used for any Git based contribution work - it's for testing, > it's for people who want to work with patches - the commits > themselves always go into persistent non-rebasing, append-only > Git trees. > > If we mess up bisectability we do a delta fix. When choosing > between somewhat better bisectability and a proper history that > others can rely on then proper history wins hands down. > Okay, we'll adopt a similar workflow for the future. -- error compiling committee.c: too many arguments to function -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
