Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932352AbZFLDNs (ORCPT ); Thu, 11 Jun 2009 23:13:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757489AbZFLDNl (ORCPT ); Thu, 11 Jun 2009 23:13:41 -0400 Received: from mga14.intel.com ([143.182.124.37]:31260 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756232AbZFLDNk (ORCPT ); Thu, 11 Jun 2009 23:13:40 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.42,206,1243839600"; d="scan'208";a="153423116" Subject: Re: [PATCH 3/3] ring-buffer: add design document From: Huang Ying To: Mathieu Desnoyers Cc: Steven Rostedt , "linux-kernel@vger.kernel.org" , Ingo Molnar , Andrew Morton , Thomas Gleixner , Peter Zijlstra , Frederic Weisbecker , Theodore Tso , Arnaldo Carvalho de Melo , Lai Jiangshan , "Martin J. Bligh" , Christoph Hellwig , Li Zefan , "H. Peter Anvin" , Hidetoshi Seto , Masami Hiramatsu In-Reply-To: <20090611023807.GA12407@Krystal> References: <20090610195311.767699959@goodmis.org> <20090610195525.429316815@goodmis.org> <1244681467.8361.654.camel@yhuang-dev.sh.intel.com> <1244687581.8361.703.camel@yhuang-dev.sh.intel.com> <20090611023807.GA12407@Krystal> Content-Type: text/plain Date: Fri, 12 Jun 2009 11:13:37 +0800 Message-Id: <1244776417.5320.160.camel@yhuang-dev.sh.intel.com> Mime-Version: 1.0 X-Mailer: Evolution 2.26.1.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 846 Lines: 24 On Thu, 2009-06-11 at 10:38 +0800, Mathieu Desnoyers wrote: > > > Are these archs without cmpxchg and NMIs, a concern for you? > > > > ARM has no cmpxchg until ARM v6, but it has NMI like mechanism named > > FIQ. > > > > One could probably adapt the cmpxchg for earlier ARM so it disables > FIQs. Note that the current limitation is that there is only a > fiq disable, not a fiq save/restore. Yes. It seems that ARM is OK after FIQ save/restore issue is fixed. Another machine with NMI but no NMI-safe cmpxchg is "real" 386. That is very old machine, does that matter? Best Regards, Huang Ying -- 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/