Re: [PATCH for-next v2] RDMA/cma: Replace RMW with atomic bit-ops

[Jason Gunthorpe <jgg@nvidia.com>]

On Mon, Jun 21, 2021 at 03:55:40PM +0000, Haakon Bugge wrote:
> 
> 
> > On 21 Jun 2021, at 17:12, Jason Gunthorpe <jgg@nvidia.com> wrote:
> > 
> > On Mon, Jun 21, 2021 at 02:58:46PM +0000, Haakon Bugge wrote:
> >> 
> >> 
> >>> On 21 Jun 2021, at 16:37, Jason Gunthorpe <jgg@nvidia.com> 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 :-)

Well, that threads from Linus seems more forceful than other threads I
recall so <shrug> Still coding-style gives the same guidance I gave
you:

 Statements longer than 80 columns should be broken into sensible chunks,
 unless exceeding 80 columns significantly increases readability and does
 not hide information.

Can't say I have anything more clever to say, other than try to follow
coding style.

Jason