> On 22 Jun 2021, at 08:16, Leon Romanovsky <leon@xxxxxxxxxx> wrote:
>
> On Mon, Jun 21, 2021 at 03:55:40PM +0000, Haakon Bugge wrote:
>>
>>
>>> On 21 Jun 2021, at 17:12, Jason Gunthorpe <jgg@xxxxxxxxxx> wrote:
>>>
>>> On Mon, Jun 21, 2021 at 02:58:46PM +0000, Haakon Bugge wrote:
>>>>
>>>>
>>>>> On 21 Jun 2021, at 16:37, Jason Gunthorpe <jgg@xxxxxxxxxx> wrote:
>>>>>
>>>>> On Mon, Jun 21, 2021 at 10:46:26AM +0000, Haakon Bugge wrote:
>>>>>
>>>>>>>> You're running an old checkpatch. Since commit bdc48fa11e46 ("checkpatch/coding-style: deprecate 80-column warning"), the default line-length is 100. As Linus states in:
>>>>>>>>
>>>>>>>> https://lkml.org/lkml/2009/12/17/229
>>>>>>>>
>>>>>>>> "... But 80 characters is causing too many idiotic changes."
>>>>>>>
>>>>>>> I'm aware of that thread, but RDMA subsystem continues to use 80 symbols limit.
>>>>>>
>>>>>> I wasn't aware. Where is that documented? Further, it must be a
>>>>>> limit that is not enforced. Of the last 100 commits in
>>>>>> drivers/infiniband, there are 630 lines longer than 80.
>>>>>
>>>>> Linus said stick to 80 but use your best judgement if going past
>>>>>
>>>>> It was not a blanket allowance to needless long lines all over the
>>>>> place.
>>>>
>>>> That is not how I interpreted him:
>>>
>>> There was a much newer thread on this from Linus, 2009 is really old
>>
>> Yes, from last year, lkml.org/lkml/2020/5/29/1038
>>
>> <quote>
>> Excessive line breaks are BAD. They cause real and every-day problems.
>>
>> They cause problems for things like "grep" both in the patterns and in
>> the output, since grep (and a lot of other very basic unix utilities)
>> is fundamentally line-based.
>>
>> So the fact is, many of us have long long since skipped the whole
>> "80-column terminal" model, for the same reason that we have many more
>> lines than 25 lines visible at a time.
>>
>> And honestly, I don't want to see patches that make the kernel reading
>> experience worse for me and likely for the vast majority of people,
>> based on the argument that some odd people have small terminal
>> windows.
>> </quote>
>>
>> Occasionally enforcing 80-chars line lengths in the RDMA subsystem seems like a strange policy to me :-)
>
> I prefer to be strict here. We are submitting patches to different
> subsystems with different reviewers.
Indeed, a fair point. But there are plenty RDMA subsystem only commits with > 80 chars and other warnings, e.g.,
c80a0c52d85c ("RDMA/cma: Add missing error handling of listen_id")
But read me correct. I am probably one of the few here reading from left to right, and interprets c-code that way better than code having excessive line breaks.
Having:
if (expression_a && expression_b) {
become:
if (expression_a &&
expression_b) {
because the former is let's say 90 chars long, clearly reduces readability in my head. After all, the coding style also says:
<quote>
The coding style document also should not be read as an absolute law which
can never be transgressed. If there is a good reason to go against the
style (a line which becomes far less readable if split to fit within the
80-column limit, for example), just do it.
</quote>
So, I'll end this here, just summing up my arguments: We have Linus' blessing for longer lines, checkpatch defaults to 100, readability gets better, and coding style allows exception from the 80 chars rule.
Thxs, Håkon
>
> "This adds a few pointles > 80 char lines."
> https://lore.kernel.org/linux-rdma/20200907072921.GC19875@xxxxxx/
>
>>
>>
>> Thxs, Håkon
>>
>>
>>>
>>> Jason
