From mboxrd@z Thu Jan  1 00:00:00 1970
From: Linus Walleij <linus.ml.walleij@gmail.com>
Subject: Re: Project Proposal: add sleeping spinlocks to mainline kernel
Date: Thu, 17 Dec 2009 10:54:23 +0100
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To: Tim Bird <tim.bird@am.sony.com>
Cc: CE Linux Developers List <celinux-dev@tree.celinuxforum.org>, linux-embedded <linux-embedded@vger.kernel.org>

2009/12/16 Tim Bird <tim.bird@am.sony.com>:

> Summary: add sleeping spinlocks to the mainline kernel

If realtime performance overall is a big deal for CELF I would suggest
adding "Kill-the-BKL" to the suggested projects. There are still some
RTOS people using the BKL as an argument to flak the Linux kernel,
c.f.
http://www.freescale.com/files/32bit/doc/ref_manual/EMBMCRM.pdf
(section 5.2)

Another item could be to go through some common embedded
arch drivers and switch them from request_irq() to request_threaded_irq()
just based on the observation that almost nobody actually use that
in the mainline kernel, though I'm sure they should,
if realtime is a desired feature.
(The wm8350-core driver is an excellent example of a situation where
it is used properly.)

NB: I'm not a member of the CE Linux Forum and nor is my company
so I'm just talking freely here. (linux-embedded is public, hehe.)

Yours,
Linus Walleij