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From: Cyrill Gorcunov <gorcunov@gmail.com>
To: Arjan van de Ven <arjan@infradead.org>
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 23:32:06 +0400	[thread overview]
Message-ID: <20070922193206.GA15911@cvg> (raw)
In-Reply-To: <20070922124659.741cca42@laptopd505.fenrus.org>

[Arjan van de Ven - Sat, Sep 22, 2007 at 12:46:59PM -0700]
| On Sat, 22 Sep 2007 12:33:55 +0400
| Cyrill Gorcunov <gorcunov@gmail.com> wrote:
| 
| > Hi list,
| > 
| > could anyone tell me why there is no official memzero function (or
| > macros) in the kernel.
| 
| it doesn't add value.... memset with a constant 0 is just as fast
| (since the compiler knows it's 0) than any wrapper around it, and the
| syntax around it is otherwise the same.
| 

It seems I expressed wrong. I'm worried about code duplication. Look
simple grep for memzero tells us that in particular:

...
-- arch/x86_64/boot/compressed/misc.c:110:#define memzero(s, n) memset ((s), 0, (n))
-- init/do_mounts_rd.c:279:#define memzero(s, n)     memset ((s), 0, (n))
-- init/initramfs.c:377:#define memzero(s, n)     memset ((s), 0, (n))
-- lib/inflate.c:331:  memzero(stk->c, sizeof(stk->c));
...

So instead of several 'define' that are the _same_ maybe better just use
_single common_ define? That's all I wanna ask. (Btw, it seems ARM has
a special case for memzero ;)

| 
| > 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.
| 
| my suggestion is to nuke all the macros and just use memset().
| 

Quite clear, thanks. So if that is OK - I'm shutting up ;)

		Cyrill


      parent reply	other threads:[~2007-09-22 19:32 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
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 [this message]

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