From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9CDE7C3A59F for ; Mon, 26 Aug 2019 19:58:16 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6F603206E0 for ; Mon, 26 Aug 2019 19:58:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="WVz9nKAK" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6F603206E0 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=nHYUA/pgCqzKNXQW3j1NOvVluF3JLokTGaZpS0katHc=; b=WVz9nKAKdrqiI6H+30yLepymM nwAKguQp9Ycf6x2HqHCOvH66Iw4yqhgheCsDaiGVMBs7oyow8pfb7yHNRevKlH1bn4V7dfnI2HkHG kZvOTAF/oQkLLoMlbpm06qZ+Rciq9mQTOyAMf3ooO9H8ggg0LnolPNgeTjJoeRQ9YaGqUU/di0x1I Pj/lZ1wb2SBV97NNTew/23svKqwdSgrX22DLtMHaH9BUnMTgabYnj7eEDHKZ/eE7hEMPIvaDYWiea Gr+ntbRmvxqJBpGt2Z41b38Hstw0t7p0Bx/Djk32Gl6KNIG/jTaiAMG+T2pIut1vH/alEQonvQZGn Oqd8ce/vA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1i2L7x-0003og-J0; Mon, 26 Aug 2019 19:58:09 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1i2L7u-0003nu-9x for linux-arm-kernel@lists.infradead.org; Mon, 26 Aug 2019 19:58:07 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 4A042337; Mon, 26 Aug 2019 12:58:05 -0700 (PDT) Received: from [10.37.9.91] (unknown [10.37.9.91]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 38E2D3F246; Mon, 26 Aug 2019 12:58:03 -0700 (PDT) Subject: Re: [RFC PATCH 5/7] arm64: smp: use generic SMP stop common code To: Christoph Hellwig References: <20190823115720.605-1-cristian.marussi@arm.com> <20190823115720.605-6-cristian.marussi@arm.com> <20190826153236.GA9591@infradead.org> From: Cristian Marussi Message-ID: Date: Mon, 26 Aug 2019 20:58:01 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20190826153236.GA9591@infradead.org> Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190826_125806_392852_CE5EC7C3 X-CRM114-Status: GOOD ( 11.57 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch@vger.kernel.org, mark.rutland@arm.com, peterz@infradead.org, catalin.marinas@arm.com, linux-kernel@vger.kernel.org, takahiro.akashi@linaro.org, james.morse@arm.com, hidehiro.kawai.ez@hitachi.com, tglx@linutronix.de, will@kernel.org, dave.martin@arm.com, linux-arm-kernel@lists.infradead.org Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi On 8/26/19 4:32 PM, Christoph Hellwig wrote: >> +config ARCH_USE_COMMON_SMP_STOP >> + def_bool y if SMP > > The option belongs into common code and the arch code shoud only > select it. > In fact that was my first approach, but then I noticed that in kernel/ topdir there was no generic Kconfig but only subsystem specific ones: Kconfig.freezer Kconfig.hz Kconfig.locks Kconfig.preempt while instead looking into archs top level Kconfig, beside the usual arch/Kconfig selects, I could find this similar sort of "reversed" approach in which the arch defined and selected a CONFIG which was indeed then used only in common code like in: 20:37 $ egrep -R ARCH_HAS_CACHE_LINE_SIZE . ./arch/arc/Kconfig:config ARCH_HAS_CACHE_LINE_SIZE ./arch/x86/Kconfig:config ARCH_HAS_CACHE_LINE_SIZE ./arch/arm64/Kconfig:config ARCH_HAS_CACHE_LINE_SIZE ./include/linux/cache.h:#ifndef CONFIG_ARCH_HAS_CACHE_LINE_SIZE 20:39 $ egrep -R ARCH_HAS_KEXEC_PURGATORY . ./arch/powerpc/Kconfig:config ARCH_HAS_KEXEC_PURGATORY ./arch/x86/Kconfig:config ARCH_HAS_KEXEC_PURGATORY ./arch/s390/Kconfig:config ARCH_HAS_KEXEC_PURGATORY ./arch/s390/purgatory/Makefile:obj-$(CONFIG_ARCH_HAS_KEXEC_PURGATORY) += kexec-purgatory.o ./arch/s390/Kbuild:obj-$(CONFIG_ARCH_HAS_KEXEC_PURGATORY) += purgatory/ ./kernel/kexec_file.c: if (!IS_ENABLED(CONFIG_ARCH_HAS_KEXEC_PURGATORY)) so I thought it was an acceptable option and I went for it, not to introduce a new kernel/Kconfig.smp just for this new config option; but in fact I could have missed the real reason underlying these two different choices. Thanks Cristian _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel