From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [v3,11/41] mips: reuse asm-generic/barrier.h Date: Tue, 12 Jan 2016 10:27:11 +0100 Message-ID: <20160112092711.GP6344@twins.programming.kicks-ass.net> References: <1452426622-4471-12-git-send-email-mst@redhat.com> <56945366.2090504@imgtec.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <56945366.2090504@imgtec.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: Leonid Yegoshin Cc: linux-mips@linux-mips.org, linux-ia64@vger.kernel.org, "Michael S. Tsirkin" , will.deacon@arm.com, virtualization@lists.linux-foundation.org, "H. Peter Anvin" , sparclinux@vger.kernel.org, Ingo Molnar , linux-arch@vger.kernel.org, linux-s390@vger.kernel.org, Russell King - ARM Linux , Arnd Bergmann , linux-sh@vger.kernel.org, x86@kernel.org, xen-devel@lists.xenproject.org, Ingo Molnar , linux-xtensa@linux-xtensa.org, james.hogan@imgtec.com, user-mode-linux-devel@lists.sourceforge.net, Stefano Stabellini , adi-buildroot-devel@lists.sourceforge.net, ddaney.cavm@gmail.com, Thomas Gleixner , linux-metag@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Andrew Cooper , linux-kernel@vger. List-Id: linux-arch.vger.kernel.org On Mon, Jan 11, 2016 at 05:14:14PM -0800, Leonid Yegoshin wrote: > This statement doesn't fit MIPS barriers variations. Moreover, there is a > reason to extend that even more specific, at least for smp_store_release and > smp_load_acquire, look into > > http://patchwork.linux-mips.org/patch/10506/ Dude, that's one horrible patch. 1) you do not make such things selectable; either the hardware needs them or it doesn't. If it does you _must_ use them, however unlikely. 2) the changelog _completely_ fails to explain the sync 0x11 and sync 0x12 semantics nor does it provide a publicly accessible link to documentation that does. 3) it really should have explained what you did with smp_llsc_mb/smp_mb__before_llsc() in _detail_. And I agree that ideally it should be split into parts. Seriously, this is _NOT_ OK. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bombadil.infradead.org ([198.137.202.9]:43175 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932750AbcALJ1w (ORCPT ); Tue, 12 Jan 2016 04:27:52 -0500 Date: Tue, 12 Jan 2016 10:27:11 +0100 From: Peter Zijlstra Subject: Re: [v3,11/41] mips: reuse asm-generic/barrier.h Message-ID: <20160112092711.GP6344@twins.programming.kicks-ass.net> References: <1452426622-4471-12-git-send-email-mst@redhat.com> <56945366.2090504@imgtec.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <56945366.2090504@imgtec.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Leonid Yegoshin Cc: "Michael S. Tsirkin" , linux-kernel@vger.kernel.org, Arnd Bergmann , linux-arch@vger.kernel.org, Andrew Cooper , Russell King - ARM Linux , virtualization@lists.linux-foundation.org, Stefano Stabellini , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Joe Perches , 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, Ralf Baechle , Ingo Molnar , ddaney.cavm@gmail.com, will.deacon@arm.com, james.hogan@imgtec.com Message-ID: <20160112092711.tKunJYfvj-meRhAwOqATVw-I0m-J82fHC84w0nQlS4c@z> On Mon, Jan 11, 2016 at 05:14:14PM -0800, Leonid Yegoshin wrote: > This statement doesn't fit MIPS barriers variations. Moreover, there is a > reason to extend that even more specific, at least for smp_store_release and > smp_load_acquire, look into > > http://patchwork.linux-mips.org/patch/10506/ Dude, that's one horrible patch. 1) you do not make such things selectable; either the hardware needs them or it doesn't. If it does you _must_ use them, however unlikely. 2) the changelog _completely_ fails to explain the sync 0x11 and sync 0x12 semantics nor does it provide a publicly accessible link to documentation that does. 3) it really should have explained what you did with smp_llsc_mb/smp_mb__before_llsc() in _detail_. And I agree that ideally it should be split into parts. Seriously, this is _NOT_ OK. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Date: Tue, 12 Jan 2016 09:27:11 +0000 Subject: Re: [v3,11/41] mips: reuse asm-generic/barrier.h Message-Id: <20160112092711.GP6344@twins.programming.kicks-ass.net> List-Id: References: <1452426622-4471-12-git-send-email-mst@redhat.com> <56945366.2090504@imgtec.com> In-Reply-To: <56945366.2090504@imgtec.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Leonid Yegoshin Cc: linux-mips@linux-mips.org, linux-ia64@vger.kernel.org, "Michael S. Tsirkin" , will.deacon@arm.com, virtualization@lists.linux-foundation.org, "H. Peter Anvin" , sparclinux@vger.kernel.org, Ingo Molnar , linux-arch@vger.kernel.org, linux-s390@vger.kernel.org, Russell King - ARM Linux , Arnd Bergmann , linux-sh@vger.kernel.org, x86@kernel.org, xen-devel@lists.xenproject.org, Ingo Molnar , linux-xtensa@linux-xtensa.org, james.hogan@imgtec.com, user-mode-linux-devel@lists.sourceforge.net, Stefano Stabellini , adi-buildroot-devel@lists.sourceforge.net, ddaney.cavm@gmail.com, Thomas Gleixner , linux-metag@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Andrew Cooper , linux-kernel@vger. On Mon, Jan 11, 2016 at 05:14:14PM -0800, Leonid Yegoshin wrote: > This statement doesn't fit MIPS barriers variations. Moreover, there is a > reason to extend that even more specific, at least for smp_store_release and > smp_load_acquire, look into > > http://patchwork.linux-mips.org/patch/10506/ Dude, that's one horrible patch. 1) you do not make such things selectable; either the hardware needs them or it doesn't. If it does you _must_ use them, however unlikely. 2) the changelog _completely_ fails to explain the sync 0x11 and sync 0x12 semantics nor does it provide a publicly accessible link to documentation that does. 3) it really should have explained what you did with smp_llsc_mb/smp_mb__before_llsc() in _detail_. And I agree that ideally it should be split into parts. Seriously, this is _NOT_ OK. From mboxrd@z Thu Jan 1 00:00:00 1970 From: peterz@infradead.org (Peter Zijlstra) Date: Tue, 12 Jan 2016 10:27:11 +0100 Subject: [v3,11/41] mips: reuse asm-generic/barrier.h In-Reply-To: <56945366.2090504@imgtec.com> References: <1452426622-4471-12-git-send-email-mst@redhat.com> <56945366.2090504@imgtec.com> Message-ID: <20160112092711.GP6344@twins.programming.kicks-ass.net> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Mon, Jan 11, 2016 at 05:14:14PM -0800, Leonid Yegoshin wrote: > This statement doesn't fit MIPS barriers variations. Moreover, there is a > reason to extend that even more specific, at least for smp_store_release and > smp_load_acquire, look into > > http://patchwork.linux-mips.org/patch/10506/ Dude, that's one horrible patch. 1) you do not make such things selectable; either the hardware needs them or it doesn't. If it does you _must_ use them, however unlikely. 2) the changelog _completely_ fails to explain the sync 0x11 and sync 0x12 semantics nor does it provide a publicly accessible link to documentation that does. 3) it really should have explained what you did with smp_llsc_mb/smp_mb__before_llsc() in _detail_. And I agree that ideally it should be split into parts. Seriously, this is _NOT_ OK.