experience with the new arm-soc workflow (Was: Re: [Ksummit-2011-discuss] ARM Maintainers workshop at Kernel Summit) 2011

[Nicolas Pitre]

On Sat, 6 Aug 2011, Uwe Kleine-König wrote:

> My thoughts about the fixes-cleanups-newfeatures separation is that it
> makes contributing harder than before.
> 
> Consider I want to contribute a series consisting of a cleanup and a new
> feature (that depends on the cleanup). And I want (or even need) to base
> this on (say) Sascha's imx tree that already has some other features.
> Now the cleanup patch should go on Sascha's (eventually empty) cleanup
> branch. But for the feature patch to go on top of both Sascha's feature
> branch and his new cleanup branch, he either needs so rebase his feature
> branch (which is (at least considered) bad) or he has to merge. I'd say
> merging is the correct approach, but the history tends to be more ugly
> than without the separation between cleanups and new features.
> And if Sascha wants to pull from me (opposed to apply the patches
> himself) he needs two merges. 
> (So it results in one merge more than before for both cases.)
> 
> I'm not sure how welcomed these additional merges are by Linus.
> 
> The obvious (to me) ways out are:
>  a) Linus can live with these merges; or
>  b) drop the separation between cleanup and features; or
>  c) Sascha doesn't publish a (fast-forward-only) tree but works with
>     a patch queue or git-rebase; or
>  d) Sascha keeps my series separate from his other stuff and requests
>     Arnd to pull two (or more) cleanup branches and two (or more)
>     feature branches; or
>  e) Sascha needs something like topgit;
> 
> As this problem didn't occur yet in real life, there might be
> 
>  f) there is no real problem.

Don't forget:

g) There are no hard rules.

> I fear a) and f) don't apply, I don't like c) and d) and I know
> Sascha won't like e).
> So there might only be b) left unless there is some g) I don't see.

Good judgment always prevails.  If you need to merge something in your 
branch, there is no problem with you asking Sascha to merge the result 
of that merge, and in turn Sascha asking the result to be merged by 
Arnd, etc.  Suffice that you justify why you want that merge, how it 
makes your contribution for the added feature on top easier, etc.  If 
the upstream maintainer asks otherwise then just try to convince that 
maintainer.  If you are right then you shouldn't have too many problem 
convincing people.

But at least always considering the fix/cleanup/feature split initially 
is certainly a good practice since that works well in most cases, and 
when that works, this makes your upstream maintainer's life a bit 
easier.


Nicolas