From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [PATCH v2 20/32] metag: define __smp_xxx Date: Mon, 4 Jan 2016 14:41:28 +0100 Message-ID: <20160104134128.GZ6344@twins.programming.kicks-ass.net> References: <1451572003-2440-1-git-send-email-mst@redhat.com> <1451572003-2440-21-git-send-email-mst@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1451572003-2440-21-git-send-email-mst@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: "Michael S. Tsirkin" Cc: linux-mips@linux-mips.org, linux-ia64@vger.kernel.org, linux-sh@vger.kernel.org, virtualization@lists.linux-foundation.org, "H. Peter Anvin" , sparclinux@vger.kernel.org, Ingo Molnar , linux-arch@vger.kernel.org, linux-s390@vger.kernel.org, Arnd Bergmann , Davidlohr Bueso , x86@kernel.org, xen-devel@lists.xenproject.org, Ingo Molnar , linux-xtensa@linux-xtensa.org, James Hogan , user-mode-linux-devel@lists.sourceforge.net, Stefano Stabellini , Andrey Konovalov , adi-buildroot-devel@lists.sourceforge.net, Thomas Gleixner , linux-metag@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Andrew Cooper , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.orgD List-Id: linux-arch.vger.kernel.org On Thu, Dec 31, 2015 at 09:08:22PM +0200, Michael S. Tsirkin wrote: > +#ifdef CONFIG_SMP > +#define fence() metag_fence() > +#else > +#define fence() do { } while (0) > #endif James, it strikes me as odd that fence() is a no-op instead of a barrier() for UP, can you verify/explain? From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bombadil.infradead.org ([198.137.202.9]:50871 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751603AbcADNlu (ORCPT ); Mon, 4 Jan 2016 08:41:50 -0500 Date: Mon, 4 Jan 2016 14:41:28 +0100 From: Peter Zijlstra Subject: Re: [PATCH v2 20/32] metag: define __smp_xxx Message-ID: <20160104134128.GZ6344@twins.programming.kicks-ass.net> References: <1451572003-2440-1-git-send-email-mst@redhat.com> <1451572003-2440-21-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1451572003-2440-21-git-send-email-mst@redhat.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: "Michael S. Tsirkin" Cc: linux-kernel@vger.kernel.org, Arnd Bergmann , linux-arch@vger.kernel.org, Andrew Cooper , virtualization@lists.linux-foundation.org, Stefano Stabellini , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , David Miller , linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-metag@vger.kernel.org, linux-mips@linux-mips.org, x86@kernel.org, user-mode-linux-devel@lists.sourceforge.net, adi-buildroot-devel@lists.sourceforge.net, linux-sh@vger.kernel.org, linux-xtensa@linux-xtensa.org, xen-devel@lists.xenproject.org, James Hogan , Ingo Molnar , Davidlohr Bueso , Andrey Konovalov Message-ID: <20160104134128.jKKXBT3_UL3vFe0Qw5Arz6Qr1eR5erhpdh3ZPO-761s@z> On Thu, Dec 31, 2015 at 09:08:22PM +0200, Michael S. Tsirkin wrote: > +#ifdef CONFIG_SMP > +#define fence() metag_fence() > +#else > +#define fence() do { } while (0) > #endif James, it strikes me as odd that fence() is a no-op instead of a barrier() for UP, can you verify/explain? From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Date: Mon, 04 Jan 2016 13:41:28 +0000 Subject: Re: [PATCH v2 20/32] metag: define __smp_xxx Message-Id: <20160104134128.GZ6344@twins.programming.kicks-ass.net> List-Id: References: <1451572003-2440-1-git-send-email-mst@redhat.com> <1451572003-2440-21-git-send-email-mst@redhat.com> In-Reply-To: <1451572003-2440-21-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: "Michael S. Tsirkin" Cc: linux-mips@linux-mips.org, linux-ia64@vger.kernel.org, linux-sh@vger.kernel.org, virtualization@lists.linux-foundation.org, "H. Peter Anvin" , sparclinux@vger.kernel.org, Ingo Molnar , linux-arch@vger.kernel.org, linux-s390@vger.kernel.org, Arnd Bergmann , Davidlohr Bueso , x86@kernel.org, xen-devel@lists.xenproject.org, Ingo Molnar , linux-xtensa@linux-xtensa.org, James Hogan , user-mode-linux-devel@lists.sourceforge.net, Stefano Stabellini , Andrey Konovalov , adi-buildroot-devel@lists.sourceforge.net, Thomas Gleixner , linux-metag@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Andrew Cooper , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.orgD On Thu, Dec 31, 2015 at 09:08:22PM +0200, Michael S. Tsirkin wrote: > +#ifdef CONFIG_SMP > +#define fence() metag_fence() > +#else > +#define fence() do { } while (0) > #endif James, it strikes me as odd that fence() is a no-op instead of a barrier() for UP, can you verify/explain? From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [PATCH v2 20/32] metag: define __smp_xxx Date: Mon, 4 Jan 2016 14:41:28 +0100 Message-ID: <20160104134128.GZ6344@twins.programming.kicks-ass.net> References: <1451572003-2440-1-git-send-email-mst@redhat.com> <1451572003-2440-21-git-send-email-mst@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1451572003-2440-21-git-send-email-mst@redhat.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: "Michael S. Tsirkin" Cc: linux-mips@linux-mips.org, linux-ia64@vger.kernel.org, linux-sh@vger.kernel.org, virtualization@lists.linux-foundation.org, "H. Peter Anvin" , sparclinux@vger.kernel.org, Ingo Molnar , linux-arch@vger.kernel.org, linux-s390@vger.kernel.org, Arnd Bergmann , Davidlohr Bueso , x86@kernel.org, xen-devel@lists.xenproject.org, Ingo Molnar , linux-xtensa@linux-xtensa.org, James Hogan , user-mode-linux-devel@lists.sourceforge.net, Stefano Stabellini , Andrey Konovalov , adi-buildroot-devel@lists.sourceforge.net, Thomas Gleixner , linux-metag@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Andrew Cooper , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, D On Thu, Dec 31, 2015 at 09:08:22PM +0200, Michael S. Tsirkin wrote: > +#ifdef CONFIG_SMP > +#define fence() metag_fence() > +#else > +#define fence() do { } while (0) > #endif James, it strikes me as odd that fence() is a no-op instead of a barrier() for UP, can you verify/explain? From mboxrd@z Thu Jan 1 00:00:00 1970 From: peterz@infradead.org (Peter Zijlstra) Date: Mon, 4 Jan 2016 14:41:28 +0100 Subject: [PATCH v2 20/32] metag: define __smp_xxx In-Reply-To: <1451572003-2440-21-git-send-email-mst@redhat.com> References: <1451572003-2440-1-git-send-email-mst@redhat.com> <1451572003-2440-21-git-send-email-mst@redhat.com> Message-ID: <20160104134128.GZ6344@twins.programming.kicks-ass.net> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Dec 31, 2015 at 09:08:22PM +0200, Michael S. Tsirkin wrote: > +#ifdef CONFIG_SMP > +#define fence() metag_fence() > +#else > +#define fence() do { } while (0) > #endif James, it strikes me as odd that fence() is a no-op instead of a barrier() for UP, can you verify/explain?