Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757557Ab2HWM0J (ORCPT ); Thu, 23 Aug 2012 08:26:09 -0400 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]:46065 "EHLO cam-admin0.cambridge.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755377Ab2HWM0G (ORCPT ); Thu, 23 Aug 2012 08:26:06 -0400 Date: Thu, 23 Aug 2012 13:25:49 +0100 From: Will Deacon To: Tixy Cc: Arnd Bergmann , Nicolas Pitre , Russell King , Leif Lindholm , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCHv3 4/4] ARM: kprobes: make more tests conditional Message-ID: <20120823122549.GD13622@mudshark.cambridge.arm.com> References: <1345645780-2749-1-git-send-email-arnd@arndb.de> <201208221519.12056.arnd@arndb.de> <201208221841.29645.arnd@arndb.de> <1345679461.3601.20.camel@computer5.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1345679461.3601.20.camel@computer5.home> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1723 Lines: 41 On Thu, Aug 23, 2012 at 12:51:01AM +0100, Tixy wrote: > On Wed, 2012-08-22 at 18:41 +0000, Arnd Bergmann wrote: > > On Wednesday 22 August 2012, Nicolas Pitre wrote: > > > On Wed, 22 Aug 2012, Arnd Bergmann wrote: > > > > > > > > > > The ldrex/strex instructions are available on ARMv6. It's only the d > > > > > variants (strexd/ldrexd) which are only available from ARMv6k. > > > > > > > > Ok. How is the version below then? I haven't tested this one yet. > > > > > > In fact, I think the b variants are ARMv6k+ as well. Only the plain > > > (non b non d) variants are available on ARMv6. > > > > Ok, third attempt then. This leaves ldrex for ARMv6 but marks > > {st,ld}rex{b,h,d} as V6K specific (which includes ARMv7). > > ARMv7 does set CPU_32v6K, because arch/arm/mm/Kconfig has > > config CPU_V7 > bool "Support ARM V7 processor" if ARCH_INTEGRATOR || MACH_REALVIEW_EB || MACH_REALVIEW_PBX > select CPU_32v6K > select CPU_32v7 > > but this seems more for peripheral reasons not because all the various > CPU configs systematically select the earlier architecture variants, > e.g. CPU_V7 doesn't select CPU_32v6. > > So I would have been inclined to test for > > #if defined(CONFIG_CPU_32v6K) || (__LINUX_ARM_ARCH__ >= 7) FWIW, the selection of the optimised atomic64 implementation for ARM (which uses the double-word exclusive instructions) boils down to CONFIG_CPU_32v6K, so I think the additional __LINUX_ARM_ARCH__ check is probably overkill. Will -- 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/