Re: [kernel.org users] b4: encouraging using the cover letter in merge commits?

From: "Jason Gunthorpe" <jgg@ziepe.ca>
To: Jakub Kicinski <kuba@kernel.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>,
	toke@toke.dk,
	Konstantin Ryabitsev <konstantin@linuxfoundation.org>,
	users@linux.kernel.org, tools@linux.kernel.org,
	Jens Axboe <axboe@kernel.dk>,
	Arnaldo Carvalho de Melo <acme@kernel.org>
Subject: Re: [kernel.org users] b4: encouraging using the cover letter in merge commits?
Date: Mon, 21 Dec 2020 15:05:52 -0400	[thread overview]
Message-ID: <20201221190552.GS5487@ziepe.ca> (raw)
In-Reply-To: <20201219092126.5633d02f@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>

On Sat, Dec 19, 2020 at 09:21:26AM -0800, Jakub Kicinski wrote:
> On Sat, 19 Dec 2020 09:03:36 -0800 James Bottomley wrote:
> > > I agree that the cover letter is useful more often than not and
> > > ideally it would be included in most cases. In netdev/bpf land the
> > > maintainers do this by always creating a merge commit when applying a
> > > multi-part series; here's Daniel applying one of mine, for instance:
> > > 
> > > https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit/?id=4e083fdfa39db29bbc7725e229e701867d0da183
> > > 
> > > I personally think this practice is pretty nice, and so I was hoping
> > > that supporting this workflow in b4 could be a way to encourage other
> > > maintainers to take up the practice as well :)  
> > 
> > I've got to say that creating a spurious merge for the cover letter
> > looks even more tortuous than creating an empty commit.  What
> > advantages does this have over the existing link tag practice which is
> > the one that we now use instead of the empty commit?
> 
> May be a chicken and an egg problem in case of other subsystems.
> 
> DaveM started creating those merge commits long before Links were 
> a thing (let alone lore). That gave netdev developers the ability 
> to provide a high level description of their work, reasons, goals 
> in the cover letter, rather than one of the commit messages. For
> a series with changes finely split for ease of review it's often
> awkward to pick on which commit to put that information.
> 
> Obviously the cover letter information may be made available via 
> the Link, but there's obvious value in seeing the information in 
> the repo, after all we don't replace commit messages with links.

My biggest problem with the cover letters is while the are in the
repository, someplace, I've never actually found one while hunting
around in the git history for clues, eg with 'git blame' or 'git log
log -p'

In fact more often than not I find the netdev cover letters through
hunting in lore, not through git.

Is there some git sequence to make it visible?

The Link header is a nicer because no matter how I end up at a commit
I can go back to an email discussion..

Jason