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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 F0676C07E96 for ; Tue, 6 Jul 2021 15:43:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CBE8361A46 for ; Tue, 6 Jul 2021 15:43:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232291AbhGFPqA (ORCPT ); Tue, 6 Jul 2021 11:46:00 -0400 Received: from mout.kundenserver.de ([212.227.126.134]:45909 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231689AbhGFPqA (ORCPT ); Tue, 6 Jul 2021 11:46:00 -0400 Received: from mail-wm1-f42.google.com ([209.85.128.42]) by mrelayeu.kundenserver.de (mreue012 [213.165.67.97]) with ESMTPSA (Nemesis) id 1MsJXG-1lCnyM1Jtq-00tjPi for ; Tue, 06 Jul 2021 17:43:20 +0200 Received: by mail-wm1-f42.google.com with SMTP id g8-20020a1c9d080000b02901f13dd1672aso1803103wme.0 for ; Tue, 06 Jul 2021 08:43:20 -0700 (PDT) X-Gm-Message-State: AOAM531CWV1+itoj5uIO/mMnzJW3KWtobzdzzqYq1g1HP+qem3ZEp7In yckVL1YG8xKtPQB6JRtQ7ggRpHAsvbYOlgbqmQA= X-Google-Smtp-Source: ABdhPJwBsFis7Wrfpc+8YKB858g/CLI2CBiJNsnWQRTLHiyax5vvrnJQpy8WfeQiYrDRSHhYgs1gDjCg+O3xCGyvehY= X-Received: by 2002:a1c:4e0c:: with SMTP id g12mr1518219wmh.120.1625586200041; Tue, 06 Jul 2021 08:43:20 -0700 (PDT) MIME-Version: 1.0 References: <20210527124356.22367-1-will@kernel.org> <20210706102634.GB24903@arm.com> <59800d6c-364a-f4be-e341-c5b531657ba3@arm.com> <20210706133314.GB20327@willie-the-truck> <87zguz7b6b.wl-maz@kernel.org> In-Reply-To: <87zguz7b6b.wl-maz@kernel.org> From: Arnd Bergmann Date: Tue, 6 Jul 2021 17:43:04 +0200 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] arm64: cache: Lower ARCH_DMA_MINALIGN to 64 (L1_CACHE_BYTES) To: Marc Zyngier Cc: Will Deacon , Robin Murphy , Catalin Marinas , Yassine Oudjana , Ard Biesheuvel , Android Kernel Team , Linux ARM , Mark Rutland , Vincent Whitchurch , linux-arm-msm Content-Type: text/plain; charset="UTF-8" X-Provags-ID: V03:K1:S7YQrlmYd6xnXMa1uchZmOQE2oMZp9+aVveBbdM/SQQLebF1i9J xR4yadcs4i03+rBai9ZfMlj5WMzKfTQRPr39/YmAYu1b6zT1LR3EfXqk0GuNEWg+2Kglxlz +WJ1uxASjoUVMq6bf6NcsWC9Z4kYgL8pVQpy6guvSSlON4Mn42oBdAQrBdtYDQhO2fzqwQ2 4v/1r9VPO6v9BVLZo0HPQ== X-UI-Out-Filterresults: notjunk:1;V03:K0:XGa4GWzCyBU=:q//42MEELRkXfgDpECyvzl DpGXkIlpFKTM3CrO5gAnZK2Ts/ghtTFooAv8uPM8YxvGJenbak9fTkvbswZdSpFWl19I0lWXx LZUW1Pmpgembm724+C0f4qsIdE8loRg1ssZ+IUQbrV3ZZsjseoJHKw/P/6FYFSXP4ap4eim2p UWWxjLByiF57ZYyu26y+luc1P/W9YXVG07YQyoqf3VTikN3zsstMBGMlv6+fHw4MdXEQd7/hs VhUUa4IzH6yTkG5YdKQzlXa0yHNoMitorp5NgE/SuccuJL2S9iXKRJ7TmveYDLei4rH1/nUom 7noLH2caSkaxN0qz7gwy5IcNWvsBUj0uYxpj8aHLZ6IhIxnzCogiwbx2ziLFuSZlTkU7r/2Zn 6p08tII+KRHhkcPVRYqDkSez3VBN9mfCLLHM3k+kh5OGVJ/AvqxNZdiHU3JfJR/A/IeHrlCdh SasUPboU40OeRldD+glUtzWIEVwp5ZqtFyO3kTzN5FJT3J9yHsXqkHSYZIIo5WNZh+tLvE4bJ 8Fh8OJlkMJSG77r3/yQ/u5G0q/RNdqA04WxjvgLJXBwjj2RTyCd5GFpsl1KVKbbF90aKMcBQw rNuAUJor7f67qok7kUi3Xnp7qenivVA9dfXn/qTS2lPO1nVsWiAlNZiSKVYJ1pcH66fAXvVwj oHfLCSkEcl+xs1Ifz7I660Q1sqkaZwwfrvsehYLAn4ehUlDhZqz15EWBbsWQ+Wn09DFLsSNSz e5Vtfhb78zWRU9hkKsFcKRi1VdBXiJ/tWWbOQ7PnYVdHR+rx66OF2zANtVxhMl+qantgoCn2+ IuM6MjYUL4ldVawLa00yT99ykL4Dj0+UQd6RIOKSCTL5TV7QR+PY09/h6P3qgZNel/QRueM Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On Tue, Jul 6, 2021 at 4:46 PM Marc Zyngier wrote: > On Tue, 06 Jul 2021 15:30:34 +0100, Arnd Bergmann wrote: > > I can only speculate on how much got reused between the two, but > > as Falkor was released only after they had already given up on > > the full-custom Kryo core, it's plausible that it incorporates bits from > > that one. In particular the cache controller is probably easy to reuse > > even if the rest of it was a new design. > > I guess we'll never find out, and I'm probably one of the few still > having some access to this HW (not even sure for how long anyway). > > I won't cry if we decide to pull the plug on it. Sure, but the Snapdragon 820E is one we do need to worry about. While the internet pretty much agrees on Falkor having 128 bytes L1 cache line, it might be good to rule out that Kryo just misreports it before we revert the patch. Yassine, could you run the 'line' and 'cache' helper from lmbench to determine what the cache topology appears to be and if that matches the CTR_EL0 contents? Something like numactl -C 0 line -M 1M numactl -C 3 line -M 1M numactl -C 0 cache numactl -C 3 cache (the numactl command helps run this both on the 'big' and 'little' cores without running into migration) Arnd 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=-5.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 6C35BC07E96 for ; Tue, 6 Jul 2021 16:12:35 +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 3CC9261A11 for ; 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Tue, 06 Jul 2021 08:43:20 -0700 (PDT) MIME-Version: 1.0 References: <20210527124356.22367-1-will@kernel.org> <20210706102634.GB24903@arm.com> <59800d6c-364a-f4be-e341-c5b531657ba3@arm.com> <20210706133314.GB20327@willie-the-truck> <87zguz7b6b.wl-maz@kernel.org> In-Reply-To: <87zguz7b6b.wl-maz@kernel.org> From: Arnd Bergmann Date: Tue, 6 Jul 2021 17:43:04 +0200 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] arm64: cache: Lower ARCH_DMA_MINALIGN to 64 (L1_CACHE_BYTES) To: Marc Zyngier Cc: Will Deacon , Robin Murphy , Catalin Marinas , Yassine Oudjana , Ard Biesheuvel , Android Kernel Team , Linux ARM , Mark Rutland , Vincent Whitchurch , linux-arm-msm X-Provags-ID: V03:K1:CZp4yBwOXt5pVI+gdg6WxOg8J4tVgi1yQ//9rn4PqxAb/UOB/Y9 Wuw0idbElB4NrPxmeNoxjOHAFowwplzgPx8uNgzrtOY+NuRPcNQenz3F5LN2fPW1Kx4QahK emmdNU2fkB0JjqvA2u2SNHqnzgBavRMjkJTWmZ9dZ3r/mOt98V75LLJsxXibj5QjHI09X1N ON/M8WdweYrNfDKDzh01Q== X-UI-Out-Filterresults: notjunk:1;V03:K0:bINLQ9d4VHk=:pHf+9XjJQJmUCVb8lfG6T4 VHBzPZkt4mqrhZIHqMW3VHAMt5u041Qt8jbeHDNoWJ4NjlNCicEFawYfX12wVVW/VVd4z1Etn YV34GLzdI3RFt9Jl5VQW5t/wubNP4fQBx+lpL6kAs3wLtGY72AjegSbO8ObUv3CxC0+28J6IZ JEQHmS7rxTqOrdhPHgp3wK45iL1uDC27JMfLlfTWsTK+8grSPCqzd1BWabfOFDyprIBnJsuJe jBkkhKpTngVBzpvk0xp+uEHJu5JIW106PUUtVNl9gyOobiMLVBvslhOmLk0xIQBvoj/KqkBpQ USwcAq+Xva4fXBalsaU1PjlO/xXwDfQY5lsLn8V7nZdgBT9Nag+Bk3ZV5ggFLmNGxad9QIhyo 99Z5cbqH64y8s3+2I+a2NeZc3Uyuma1NEKzmyeoImKL9lBYk/ERSc5tg552FC3PtcnKqe6gEa FGxLVqAzqLXJxjzKWPdFFTbLCqiuIBZ0Q+bSE6njrEzJWm/dP7oxfSZmkNTuncXH2rskaCzS+ uXhPlJZjZioLRGLwa6rI0JWs5o1H6IGzTem2XH5EVbR3Cf996v86vsx5zSDuPS2OArw0MrGEJ p8tMEwanQ/oKDzI77aSg0+OXA6g74sXqjQkNR2Mv4rBV07NIsiM4RHAy1m+2V9assTYA0J+C0 RGbsIWA9RFPPGfwG5qeoGLcDTqA5JdbRW/j8ljeVuhpJ6Vus/XqWTkrB7ALahal3hDjrYfrzc wm8H/5e5QCCYmjq443rsvmRzqUMlnA6vOmgWykLKtJCJhIRZGIhj4fr6GXTXlzPiAdSd9n1Y/ vW1myozwzlAcKoLP15CeCc2FtaZo0fgjaEkt+S+25rwCnJXsi0fqFmOkaeBa2cmgf5iUYZYuq nSHPW/mScdOh/sQs7YEniMQKwicI/CCzgP2pXK9JeMl2cf37kRiJkgS8vmiVCmXFTIwo2xUs0 nTF62dbdDy1lGZvLpMqYhXR3BN9Dj6ppN1tiFpsWiOz5ISGlP67VD X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210706_091046_259252_9FA7D628 X-CRM114-Status: GOOD ( 19.86 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Jul 6, 2021 at 4:46 PM Marc Zyngier wrote: > On Tue, 06 Jul 2021 15:30:34 +0100, Arnd Bergmann wrote: > > I can only speculate on how much got reused between the two, but > > as Falkor was released only after they had already given up on > > the full-custom Kryo core, it's plausible that it incorporates bits from > > that one. In particular the cache controller is probably easy to reuse > > even if the rest of it was a new design. > > I guess we'll never find out, and I'm probably one of the few still > having some access to this HW (not even sure for how long anyway). > > I won't cry if we decide to pull the plug on it. Sure, but the Snapdragon 820E is one we do need to worry about. While the internet pretty much agrees on Falkor having 128 bytes L1 cache line, it might be good to rule out that Kryo just misreports it before we revert the patch. Yassine, could you run the 'line' and 'cache' helper from lmbench to determine what the cache topology appears to be and if that matches the CTR_EL0 contents? Something like numactl -C 0 line -M 1M numactl -C 3 line -M 1M numactl -C 0 cache numactl -C 3 cache (the numactl command helps run this both on the 'big' and 'little' cores without running into migration) Arnd _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel