From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Brown Subject: Re: [PATCH] spi/pl022: Add high priority message pump support Date: Wed, 25 Jan 2012 14:02:15 +0000 Message-ID: <20120125140215.GB2054@sirena.org.uk> References: <1327439672-638-1-git-send-email-linus.walleij@stericsson.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: spi-devel-general-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, Viresh Kumar , Chris Blair , Linus Walleij To: Linus Walleij Return-path: Content-Disposition: inline In-Reply-To: <1327439672-638-1-git-send-email-linus.walleij-0IS4wlFg1OjSUeElwK9/Pw@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: spi-devel-general-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-spi.vger.kernel.org On Tue, Jan 24, 2012 at 10:14:32PM +0100, Linus Walleij wrote: > From: Chris Blair > > This switches the PL022 worker to a kthread in order to get > hold of a mechanism to control the message pump priority. On > low-latency systems elevating the message kthread to realtime > priority give a real sleek response curve. This has been > confirmed by measurements. Realtime priority elevation for > a certain PL022 port can be requested from platform data. It really feels like we should be pulling this into the core - lots of drivers use a workqueue to drive data through the system and they're all going to have exactly the same issue. ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d