From: Sasha Levin <levinsasha928@gmail.com>
To: "N. Coesel" <nico@nctdev.nl>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Fast memcpy patch
Date: Wed, 23 Nov 2011 14:10:41 +0200 [thread overview]
Message-ID: <1322050241.3581.15.camel@lappy> (raw)
In-Reply-To: <CPSMTPM-CMT101y332G000633f8@CPSMTPM-CMT101.kpnxchange.com>
On Wed, 2011-11-23 at 12:25 +0100, N. Coesel wrote:
> Dear readers,
> I noticed the Linux kernel still uses a byte-by-byte copy method for
> memcpy. Since most memory allocations are aligned to the integer size
> of a cpu it is often faster to copy by using the CPU's native word
> size. The patch below does that. The code is already at work in many
> 16 and 32 bit embedded products. It should also work for 64 bit
> platforms. So far I only tested 16 and 32 bit platforms.
[snip]
memcpy (along with other mem* functions) are arch specific - for
example, look at arch/x86/lib/memcpy_64.S for the implementation(s) for
x86.
The code under lib/string.c is simple and should work on all platforms
(and is probably not being used anywhere anymore).
--
Sasha.
next prev parent reply other threads:[~2011-11-23 12:12 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-11-23 11:25 Fast memcpy patch N. Coesel
2011-11-23 11:45 ` Mihai Donțu
2011-11-23 12:07 ` N. Coesel
2011-11-23 12:06 ` richard -rw- weinberger
2011-11-23 12:07 ` Cong Wang
2011-11-23 12:10 ` Sasha Levin [this message]
2011-11-23 12:51 ` N. Coesel
2011-11-23 13:04 ` Sasha Levin
2011-11-23 20:38 ` N. Coesel
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