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From: Cyrill Gorcunov <gorcunov@gmail.com>
To: "Robert P. J. Day" <rpjday@mindspring.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>,
	LKML <linux-kernel@vger.kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Ingo Molnar <mingo@elte.hu>,
	Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: memset as memzero
Date: Sat, 22 Sep 2007 13:35:07 +0400	[thread overview]
Message-ID: <20070922093507.GB7226@cvg> (raw)
In-Reply-To: <Pine.LNX.4.64.0709220441090.21302@localhost.localdomain>

[Robert P. J. Day - Sat, Sep 22, 2007 at 04:48:28AM -0400]
| On Sat, 22 Sep 2007, Cyrill Gorcunov wrote:
| 
| > Hi list,
| >
| > could anyone tell me why there is no official memzero function (or
| > macros) in the kernel. As I see a lot of kernel parts calls for it
| > (defying own macros as alias to memset). Maybe there is a special
| > reason not to do so? Actually my suggestion is to define _one_
| > general macros for this.
| 
| i brought up this issue on the KJ list once upon a time:
| 
| https://lists.linux-foundation.org/pipermail/kernel-janitors/2007-February/017847.html
| 
| and there didn't seem to be much enthusiasm for it.
| 
|   however, i am still curious why there isn't more use of the
| already-defined "clear_page" macro.  most architectures appear to
| define it:
| 
| $ grep -r "define.*clear_page" include
| 
| but there are still numerous explicit calls to memset() to zero a
| chunk of memory that is exactly PAGE_SIZE in size.  just an
| observation.
| 
| rday
| -- 
| ========================================================================
| Robert P. J. Day
| Linux Consulting, Training and Annoying Kernel Pedantry
| Waterloo, Ontario, CANADA
| 
| http://crashcourse.ca
| ========================================================================
| 

Thanks Robert for the answer, I'll mark this (clear_page) in my "must to
take a look" list ;)
Well if there is no strong reason of keeping this separate '#define memzero'
I think it's a good case to merge them in some _single_ #define ;)

Waiting for other comments...

P.S.
In a mail you pointed to said that memset(...,0,...) is quite clear -
yes it's quite clear indeed but we already _have_ a lot of '#define memzero'
and who knows or may give the guarantee that new '#define memzero '_will not_'
appear in the kernel.

		Cyrill


  reply	other threads:[~2007-09-22  9:35 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-09-22  8:33 memset as memzero Cyrill Gorcunov
2007-09-22  8:48 ` Robert P. J. Day
2007-09-22  9:35   ` Cyrill Gorcunov [this message]
2007-09-22  9:55     ` Robert P. J. Day
2007-09-22 10:15       ` Cyrill Gorcunov
2007-09-22 19:46 ` Arjan van de Ven
2007-09-22 18:53   ` Linus Torvalds
2007-09-23 15:32     ` Dave Jones
2007-09-23 16:07       ` Arnaldo Carvalho de Melo
2007-09-23 17:05         ` Linus Torvalds
2007-09-23 18:46           ` Willy Tarreau
2007-09-23 16:33       ` Robert P. J. Day
2007-09-23 16:46         ` Arnaldo Carvalho de Melo
2007-09-22 19:25   ` Bernd Eckenfels
2007-09-22 20:37     ` Oleg Verych (nntp)
2007-09-22 19:32   ` Cyrill Gorcunov

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