Re: [PATCH 03/47] block-rbd: Adjust the position of a jump label in rbd_header_from_disk()

From: Ilya Dryomov
Date: Tue Sep 13 2016 - 11:30:47 EST


On Tue, Sep 13, 2016 at 4:36 PM, Jean Delvare <jdelvare@xxxxxxx> wrote:
> Hi Ilya,
>
> Thanks for adding me.
>
> On Tue, 13 Sep 2016 11:16:13 +0200, Ilya Dryomov wrote:
>> On Tue, Sep 13, 2016 at 10:12 AM, SF Markus Elfring
>> <elfring@xxxxxxxxxxxxxxxxxxxxx> wrote:
>> >>> @@ -1064,7 +1064,7 @@ static int rbd_header_from_disk(struct rbd_device *rbd_dev,
>> >>> header->snap_sizes = snap_sizes;
>> >>>
>> >>> return 0;
>> >>> -out_2big:
>> >>> + out_2big:
>> >>> ret = -EIO;
>> >>> kfree(snap_sizes);
>> >>> free_names:
>> > â
>> >> Can you point where this current convention is documented?
>> >
>> > Yes.
>> > https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/commit/Documentation/CodingStyle?id=865a1caa4b6b886babdd9d67e7c3608be4567a51
>>
>> Huh. That patch is not in Linus' tree.
>>
>> >
>> > Do you find the software update "CodingStyle: Clarify and complete chapter 7" interesting?
>> >
>> >
>> >> Certainly not in CodingStyle, AFAICT...
>> >
>> > I suggest to look at the current version once more.
>> >
>> >
>> >> I know some people prefer a single space in there because it makes
>> >> "diff -p" work better, but nowadays with "git diff" this argument is
>> >> pretty moot.
>> >
>> > Would you like to discuss the corresponding software evolution a bit more?
>>
>> Jon, could you please yank 865a1caa4b6b ("CodingStyle: Clarify and
>> complete chapter 7") from your linux-next branch or at least change "It
>> is advised to indent labels" to something less stronger? It hasn't
>> even hit mainline yet and we are already getting spammed.
>
> The problem isn't the documentation update nor whether you or me like a
> space before labels or not. The problem is Markus Elfring. The guy just
> spend his time flooding maintainers with unneeded changes they never
> asked for. Ignore him and you'll be much better. If he was not flooding
> you with this, he would find something else :-(
>
> When I wrote "It is advised to indent labels with one space", I never
> meant that all the existing code should be converted that way. I

Hi Jean,

That much is clear, however ...

> expressed a preference, and provided a rationale for this preference.
> After that, an advice is just that: an advice.
>
>> Looks like 9 out of 10 labels are not indented
>>
>> $ git grep '^[a-z0-9]\+:' -- *.c | wc -l
>> 27945
>> $ git grep '^ [a-z0-9]\+:' -- *.c | wc -l
>> 2925
>
> Your regexps are wrong ;-) but the ratio is correct.

... one of the main points of any coding style is consistency. When
someone new wanting to submit say a new driver opens CodingStyle and
sees "It is advised to indent labels ...", they might start indenting
labels in their code and advise others to do the same. Given the 9/10
existing ratio, that advice is wrong. If I wanted to clarify the
situation, I'd have gone with "one space indented labels are also
acceptable" or so. The example you've re-indented dates back to 2.6.4
times...

>
>> so I'd say that's a bad advise as far as consistency goes, and the
>> "diff -p" argument is pretty moot nowadays.
>
> It wasn't moot when I sent the documentation update patch. Or why would
> you think it was? "git diff", by default, behaves exactly the same as
> "diff -p" with regards to unindented labels (i.e. it doesn't handle
> them properly.)

The git diff xfuncname incantation is a few years old now. git diff
also works on regular files, BTW.

>
> However, since then the issue was discussed somewhere else:
> https://lkml.org/lkml/2016/9/5/214
>
> As you can see, alternatives to indenting labels with one space were
> found. Therefore you will soon be correct saying "the diff -p argument
> is pretty moot." As soon as my patch hits mainline, actually. Which
> shouldn't take too long as Andrew Morton picked it 4 days ago.
>
> Once this happens, I'm fine with CodingStyle being updated again to
> reflect the current situation.

I'm not sure which patch you are talking about - the message you linked
is not a patch and it's impossible to follow large threads on lkml.org.

Thanks,

Ilya