Re: [PATCH 1/3] mm: page_alloc: Reduce object size by neatening printks

From: Michal Hocko
Date: Fri Mar 17 2017 - 03:40:00 EST


On Thu 16-03-17 13:32:23, Joe Perches wrote:
> On Thu, 2017-03-16 at 11:56 +0100, Michal Hocko wrote:
> > On Wed 15-03-17 18:43:13, Joe Perches wrote:
> > > Function calls with large argument counts cause x86-64 register
> > > spilling. Reducing the number of arguments in a multi-line printk
> > > by converting to multiple printks which saves some object code size.
> > >
> > > $ size mm/page_alloc.o* (defconfig)
> > > text data bss dec hex filename
> > > 35914 1699 628 38241 9561 mm/page_alloc.o.new
> > > 36018 1699 628 38345 95c9 mm/page_alloc.o.old
> > >
> > > Miscellanea:
> > >
> > > o Remove line leading spaces from the formerly multi-line printks
> > > commit a25700a53f71 ("mm: show bounce pages in oom killer output")
> > > back in 2007 started the leading space when a single long line
> > > was split into multiple lines but the leading space was likely
> > > mistakenly kept and subsequent commits followed suit.
> > > o Align arguments in a few more printks
> >
> > This is really hard to review. Could you just drop all the whitespace
> > changes please?
>
> It's a single, simple change.

no it adds a lot of whitespace noise to an actual change. It takes to
check every single line to see whether some typo or unintended change
has been made.

> It's IMO trivial to review.

it's not IMNSHO.
--
Michal Hocko
SUSE Labs