From: Alexey Dobriyan <adobriyan@gmail.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: akpm@linux-foundation.org, containers@lists.linux-foundation.org,
xemul@parallels.com, serue@us.ibm.com, dave@linux.vnet.ibm.com,
orenl@cs.columbia.edu, hch@infradead.org,
torvalds@linux-foundation.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 01/30] headers: fixup cred.h, ipc_namespace.h
Date: Fri, 10 Apr 2009 17:17:01 +0400 [thread overview]
Message-ID: <20090410131701.GA3683@x200.localdomain> (raw)
In-Reply-To: <20090410084747.GB17962@elte.hu>
On Fri, Apr 10, 2009 at 10:47:47AM +0200, Ingo Molnar wrote:
>
> * Alexey Dobriyan <adobriyan@gmail.com> wrote:
> > +struct kern_ipc_perm;
> Please, not yet another forward declaration...
>
> I believe this should be cleaned up properly, instead of sprinkling
> the kernel with random placed forward declarations.
It's at the top of the file, there is no random placing going on.
> In a cleanly structured piace of code there's rarely any need for
> forward declarations like this. There's two basic header types
> needed:
>
> foo_types.h declares all the data types and constants
> [no complex inline functions]
>
> foo.h externs, complex inlines
>
> foo.h includes all foo_types.h and bar_types.h headers it needs.
>
> The foo_types.h file includes all other bar_types.h headers it
> depends on for its data type definitions.
>
> foo_types.h never includes a bar.h file.
This can be viewed as bad precedent created by mm_types.h.
Look how many headers mm_types.h includes. It doesn't change much
if one includes mm.h or mm_types.h.
Look how many places includes spinlock_types.h
> The end result will be a clean hieararchy of data types, separated
> from methods. Complex inlines dont create the incestous
> cross-dependency hell anymore and dont contaminate the foo_types.h
> files.
>
> Yes, this is quite a bit of work, but this has been done before for
> several complex headers so it's possible to do it.
Forward declarations are currently well established.
Want to change rules? Fine, do it.
prev parent reply other threads:[~2009-04-10 13:17 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-04-10 2:32 [PATCH 01/30] headers: fixup cred.h, ipc_namespace.h Alexey Dobriyan
2009-04-10 8:47 ` Ingo Molnar
2009-04-10 13:17 ` Alexey Dobriyan [this message]
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=20090410131701.GA3683@x200.localdomain \
--to=adobriyan@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=containers@lists.linux-foundation.org \
--cc=dave@linux.vnet.ibm.com \
--cc=hch@infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=orenl@cs.columbia.edu \
--cc=serue@us.ibm.com \
--cc=torvalds@linux-foundation.org \
--cc=xemul@parallels.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
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;
as well as URLs for NNTP newsgroup(s).