Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759500AbbKTHyT (ORCPT ); Fri, 20 Nov 2015 02:54:19 -0500 Received: from www.linutronix.de ([62.245.132.108]:47146 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754664AbbKTHyS (ORCPT ); Fri, 20 Nov 2015 02:54:18 -0500 Date: Fri, 20 Nov 2015 08:53:34 +0100 (CET) From: Thomas Gleixner To: Marcelo Tosatti cc: LKML , Peter Zijlstra , x86@kernel.org, Luiz Capitulino , Vikas Shivappa , Tejun Heo , Yu Fenghua Subject: Re: [RFD] CAT user space interface revisited In-Reply-To: <20151119205925.GA13727@amt.cnet> Message-ID: References: <20151119000153.GA27997@amt.cnet> <20151119010535.GA30233@amt.cnet> <20151119205925.GA13727@amt.cnet> User-Agent: Alpine 2.11 (DEB 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1159 Lines: 33 On Thu, 19 Nov 2015, Marcelo Tosatti wrote: > On Thu, Nov 19, 2015 at 10:09:03AM +0100, Thomas Gleixner wrote: > > On Wed, 18 Nov 2015, Marcelo Tosatti wrote > > > Actually, there is a point that is useful: you might want the important > > > application to share the L3 portion with HW (that HW DMAs into), and > > > have only the application and the HW use that region. > > > > > > So its a good point that controlling the exact position of the reservation > > > is important. > > > > I'm glad you figured that out yourself. :) > > > > Thanks, > > > > tglx > > The HW is a reclaimer of the L3 region shared with HW. > > You might want to remove any threads from reclaiming from > that region. I might for some threads, but certainly not for those which need to access DMA buffers. Throwing away 10% of L3 just because you don't want to deal with it at the interface level is hillarious. Thanks, tglx -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/