From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [PATCH v3] ad7877: keep dma rx buffers in seperate cache lines Date: Mon, 10 May 2010 13:54:17 -0700 Message-ID: <20100510205416.GB30878@core.coreip.homeip.net> References: <1273487642-2169-1-git-send-email-os@emlix.com> <1273488154-2993-1-git-send-email-os@emlix.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pv0-f174.google.com ([74.125.83.174]:62720 "EHLO mail-pv0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751415Ab0EJUyW (ORCPT ); Mon, 10 May 2010 16:54:22 -0400 Content-Disposition: inline In-Reply-To: Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Mike Frysinger Cc: Oskar Schirmer , Michael Hennerich , Andrew Morton , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, Daniel =?iso-8859-1?Q?Gl=F6ckner?= , Oliver Schneidewind , Johannes Weiner On Mon, May 10, 2010 at 12:39:49PM -0400, Mike Frysinger wrote: > On Mon, May 10, 2010 at 06:42, Oskar Schirmer wrote: > > With dma based spi transmission, data corruption > > is observed occasionally. With dma buffers located > > right next to msg and xfer fields, cache lines > > correctly flushed in preparation for dma usage > > may be polluted again when writing to fields > > in the same cache line. > > > > Make sure cache fields used with dma do not > > share cache lines with fields changed during > > dma handling. As both fields are part of a > > struct that is allocated via kzalloc, thus > > cache aligned, moving the fields to the 1st > > position and insert padding for alignment > > does the job. > > Acked-by: Mike Frysinger > > i'm guessing Dmitry will pick it up now Yep. -- Dmitry