From: arnd@arndb.de (Arnd Bergmann)
To: linux-arm-kernel@lists.infradead.org
Subject: Questions about FPU and NEON on Cortex-A9 with armv7 instructions!
Date: Wed, 28 Jul 2010 12:46:02 +0200 [thread overview]
Message-ID: <201007281246.03033.arnd@arndb.de> (raw)
In-Reply-To: <AANLkTinoZ0GT5FFUFPmU5gQK1zVcZKYtSWpHDQ1Y4OXO@mail.gmail.com>
On Wednesday 28 July 2010, David Yang wrote:
> If the other kernel code doesn't save and restore the FPU context,then
> it's risky.
>
> Can I use FPU just in one C file ?
Usually if you need something like this, you're doing something wrong.
Code that does a lot of computation should go generally live in user
space, not a kernel module, though there are a few exceptions.
Take a look at how drivers/md/raid6sse2.c uses kernel_fpu_begin() to
do this on x86.
Arnd
prev parent reply other threads:[~2010-07-28 10:46 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-07-28 6:19 Questions about FPU and NEON on Cortex-A9 with armv7 instructions! David Yang
2010-07-28 8:57 ` Martin Guy
2010-07-28 9:16 ` David Yang
2010-07-28 9:31 ` Gilles Chanteperdrix
2010-07-28 10:06 ` David Yang
2010-07-28 10:45 ` Gilles Chanteperdrix
2010-07-28 10:46 ` Arnd Bergmann [this message]
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