public inbox for netdev@vger.kernel.org 
 help / color / mirror / Atom feed
From: Andy Shevchenko <andriy.shevchenko@linux•intel.com>
To: "Alejandro Colomar (man-pages)" <alx.manpages@gmail•com>
Cc: Arnd Bergmann <arnd@arndb•de>,
	LKML <linux-kernel@vger•kernel.org>,
	Ajit Khaparde <ajit.khaparde@broadcom•com>,
	Andrew Morton <akpm@linux-foundation•org>,
	Bjorn Andersson <bjorn.andersson@linaro•org>,
	Borislav Petkov <bp@suse•de>, Corey Minyard <cminyard@mvista•com>,
	Chris Mason <clm@fb•com>,
	Christian Brauner <christian.brauner@ubuntu•com>,
	David Sterba <dsterba@suse•com>,
	Jani Nikula <jani.nikula@linux•intel.com>,
	Jason Wang <jasowang@redhat•com>,
	Jitendra Bhivare <jitendra.bhivare@broadcom•com>,
	John Hubbard <jhubbard@nvidia•com>,
	"John S . Gruber" <JohnSGruber@gmail•com>,
	Jonathan Cameron <Jonathan.Cameron@huawei•com>,
	Joonas Lahtinen <joonas.lahtinen@linux•intel.com>,
	Josef Bacik <josef@toxicpanda•com>,
	Kees Cook <keescook@chromium•org>,
	Ketan Mukadam <ketan.mukadam@broadcom•com>,
	Len Brown <lenb@kernel•org>,
	"Michael S. Tsirkin" <mst@redhat•com>,
	Miguel Ojeda <ojeda@kernel•org>,
	Mike Rapoport <rppt@linux•ibm.com>,
	Nick Desaulniers <ndesaulniers@google•com>,
	"Rafael J. Wysocki" <rafael@kernel•org>,
	Rasmus Villemoes <linux@rasmusvillemoes•dk>,
	Rodrigo Vivi <rodrigo.vivi@intel•com>,
	Russell King <linux@armlinux•org.uk>,
	Somnath Kotur <somnath.kotur@broadcom•com>,
	Sriharsha Basavapatna <sriharsha.basavapatna@broadcom•com>,
	Subbu Seetharaman <subbu.seetharaman@broadcom•com>,
	intel-gfx@lists•freedesktop.org, linux-acpi@vger•kernel.org,
	linux-arm-kernel@lists•infradead.org,
	linux-btrfs@vger•kernel.org, linux-scsi@vger•kernel.org,
	netdev@vger•kernel.org,
	virtualization@lists•linux-foundation.org
Subject: Re: [PATCH 00/17] Add memberof(), split some headers, and slightly simplify code
Date: Fri, 19 Nov 2021 17:34:53 +0200	[thread overview]
Message-ID: <YZfEHZa3f5MXeqoH@smile.fi.intel.com> (raw)
In-Reply-To: <434296d3-8fe1-f1d2-ee9d-ea25d6c4e43e@gmail.com>

On Fri, Nov 19, 2021 at 04:06:27PM +0100, Alejandro Colomar (man-pages) wrote:
> Hi Arnd,
> 
> On 11/19/21 15:47, Arnd Bergmann wrote:
> > On Fri, Nov 19, 2021 at 12:36 PM Alejandro Colomar
> > <alx.manpages@gmail•com> wrote:
> >>
> >> Alejandro Colomar (17):
> >>   linux/container_of.h: Add memberof(T, m)
> >>   Use memberof(T, m) instead of explicit NULL dereference
> >>   Replace some uses of memberof() by its wrappers
> >>   linux/memberof.h: Move memberof() to separate header
> >>   linux/typeof_member.h: Move typeof_member() to a separate header
> >>   Simplify sizeof(typeof_member()) to sizeof_field()
> >>   linux/NULL.h: Move NULL to a separate header
> >>   linux/offsetof.h: Move offsetof(T, m) to a separate header
> >>   linux/offsetof.h: Implement offsetof() in terms of memberof()
> >>   linux/container_of.h: Implement container_of_safe() in terms of
> >>     container_of()
> >>   linux/container_of.h: Cosmetic
> >>   linux/container_of.h: Remove unnecessary cast to (void *)
> > 
> > My feeling is that this takes the separation too far: by having this many header
> > files that end up being included from practically every single .c file
> > in the kernel,
> > I think you end up making compile speed worse overall.
> > 
> > If your goal is to avoid having to recompile as much of the kernel
> > after touching
> > a header, I think a better approach is to help untangle the dependencies, e.g.
> > by splitting out type definitions from headers with inline functions (most
> > indirect header dependencies are on type definitions) and by focusing on
> > linux/fs.h, linux/sched.h, linux/mm.h and how they interact with the rest of the
> > headers. At the moment, these are included in most .c files and they in turn
> > include a ton of other headers.
> 
> Yes, I would like to untangle the dependencies.
> 
> The main reason I started doing this splitting
> is because I wouldn't be able to include
> <linux/stddef.h> in some headers,
> because it pulled too much stuff that broke unrelated things.
> 
> So that's why I started from there.
> 
> I for example would like to get NULL in memberof()
> without puling anything else,
> so <linux/NULL.h> makes sense for that.

I don't believe that the code that uses NULL won't include types.h.

-- 
With Best Regards,
Andy Shevchenko



  reply	other threads:[~2021-11-19 15:35 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-11-19 11:36 [PATCH 00/17] Add memberof(), split some headers, and slightly simplify code Alejandro Colomar
2021-11-19 11:36 ` [PATCH 02/17] Use memberof(T, m) instead of explicit NULL dereference Alejandro Colomar
2021-11-23 18:07   ` Rafael J. Wysocki
2021-11-19 12:47 ` [PATCH 00/17] Add memberof(), split some headers, and slightly simplify code Jani Nikula
2021-11-19 13:16   ` Alejandro Colomar (man-pages)
2021-11-19 13:48     ` Jani Nikula
2021-11-19 14:54     ` Andy Shevchenko
2021-11-19 14:47 ` Arnd Bergmann
2021-11-19 15:06   ` Alejandro Colomar (man-pages)
2021-11-19 15:34     ` Andy Shevchenko [this message]
2021-11-19 15:38       ` Alejandro Colomar (man-pages)
2021-11-19 15:57     ` Arnd Bergmann
2021-11-19 16:10       ` Andy Shevchenko
2021-11-19 16:18         ` Arnd Bergmann
2021-11-19 16:22           ` Alejandro Colomar (man-pages)
2021-11-19 16:27             ` Arnd Bergmann
2021-11-19 16:35             ` Andy Shevchenko
2021-11-22 12:36               ` Jonathan Cameron
2021-11-19 16:12       ` Alejandro Colomar (man-pages)
2021-11-19 16:25         ` Arnd Bergmann
2021-11-19 16:37         ` Andy Shevchenko

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=YZfEHZa3f5MXeqoH@smile.fi.intel.com \
    --to=andriy.shevchenko@linux$(echo .)intel.com \
    --cc=JohnSGruber@gmail$(echo .)com \
    --cc=Jonathan.Cameron@huawei$(echo .)com \
    --cc=ajit.khaparde@broadcom$(echo .)com \
    --cc=akpm@linux-foundation$(echo .)org \
    --cc=alx.manpages@gmail$(echo .)com \
    --cc=arnd@arndb$(echo .)de \
    --cc=bjorn.andersson@linaro$(echo .)org \
    --cc=bp@suse$(echo .)de \
    --cc=christian.brauner@ubuntu$(echo .)com \
    --cc=clm@fb$(echo .)com \
    --cc=cminyard@mvista$(echo .)com \
    --cc=dsterba@suse$(echo .)com \
    --cc=intel-gfx@lists$(echo .)freedesktop.org \
    --cc=jani.nikula@linux$(echo .)intel.com \
    --cc=jasowang@redhat$(echo .)com \
    --cc=jhubbard@nvidia$(echo .)com \
    --cc=jitendra.bhivare@broadcom$(echo .)com \
    --cc=joonas.lahtinen@linux$(echo .)intel.com \
    --cc=josef@toxicpanda$(echo .)com \
    --cc=keescook@chromium$(echo .)org \
    --cc=ketan.mukadam@broadcom$(echo .)com \
    --cc=lenb@kernel$(echo .)org \
    --cc=linux-acpi@vger$(echo .)kernel.org \
    --cc=linux-arm-kernel@lists$(echo .)infradead.org \
    --cc=linux-btrfs@vger$(echo .)kernel.org \
    --cc=linux-kernel@vger$(echo .)kernel.org \
    --cc=linux-scsi@vger$(echo .)kernel.org \
    --cc=linux@armlinux$(echo .)org.uk \
    --cc=linux@rasmusvillemoes$(echo .)dk \
    --cc=mst@redhat$(echo .)com \
    --cc=ndesaulniers@google$(echo .)com \
    --cc=netdev@vger$(echo .)kernel.org \
    --cc=ojeda@kernel$(echo .)org \
    --cc=rafael@kernel$(echo .)org \
    --cc=rodrigo.vivi@intel$(echo .)com \
    --cc=rppt@linux$(echo .)ibm.com \
    --cc=somnath.kotur@broadcom$(echo .)com \
    --cc=sriharsha.basavapatna@broadcom$(echo .)com \
    --cc=subbu.seetharaman@broadcom$(echo .)com \
    --cc=virtualization@lists$(echo .)linux-foundation.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox