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From:   oddtux <lpf.vector@gmail.com>
Date:   Tue, 2 Jul 2019 19:51:59 +0800
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Subject: Re: [PATCH 0/5] mm/vmalloc.c: improve readability and rewrite vmap_area
To:     Michal Hocko <mhocko@kernel.org>
Cc:     akpm@linux-foundation.org, peterz@infradead.org, urezki@gmail.com,
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Michal Hocko <mhocko@kernel.org> =E4=BA=8E2019=E5=B9=B47=E6=9C=881=E6=97=A5=
=E5=91=A8=E4=B8=80 =E4=B8=8B=E5=8D=885:20=E5=86=99=E9=81=93=EF=BC=9A
>
> On Sun 30-06-19 15:56:45, Pengfei Li wrote:
> > Hi,
> >
> > This series of patches is to reduce the size of struct vmap_area.
> >
> > Since the members of struct vmap_area are not being used at the same ti=
me,
> > it is possible to reduce its size by placing several members that are n=
ot
> > used at the same time in a union.
> >
> > The first 4 patches did some preparatory work for this and improved
> > readability.
> >
> > The fifth patch is the main patch, it did the work of rewriting vmap_ar=
ea.
> >
> > More details can be obtained from the commit message.
>
> None of the commit messages talk about the motivation. Why do we want to
> add quite some code to achieve this? How much do we save? This all
> should be a part of the cover letter.
>

Hi Michal,

Thank you for your comments.

Sorry for the commit without any test data.
I will add motivation and necessary test data in the next version.

Best regards,

Pengfei

> > Thanks,
> >
> > Pengfei
> >
> > Pengfei Li (5):
> >   mm/vmalloc.c: Introduce a wrapper function of insert_vmap_area()
> >   mm/vmalloc.c: Introduce a wrapper function of
> >     insert_vmap_area_augment()
> >   mm/vmalloc.c: Rename function __find_vmap_area() for readability
> >   mm/vmalloc.c: Modify function merge_or_add_vmap_area() for readabilit=
y
> >   mm/vmalloc.c: Rewrite struct vmap_area to reduce its size
> >
> >  include/linux/vmalloc.h |  28 +++++---
> >  mm/vmalloc.c            | 144 +++++++++++++++++++++++++++-------------
> >  2 files changed, 117 insertions(+), 55 deletions(-)
> >
> > --
> > 2.21.0
>
> --
> Michal Hocko
> SUSE Labs