[{"id":3675889,"web_url":"http://patchwork.ozlabs.org/comment/3675889/","msgid":"<9db9515b-08e8-47bd-aced-206ac183195a@linux.intel.com>","date":"2026-04-10T13:45:43","subject":"Re: [patch 09/38] iommu/vt-d: Use sched_clock() instead of\n get_cycles()","submitter":{"id":73538,"url":"http://patchwork.ozlabs.org/api/people/73538/","name":"Baolu Lu","email":"baolu.lu@linux.intel.com"},"content":"On 4/10/2026 8:19 PM, Thomas Gleixner wrote:\n> Calculating the timeout from get_cycles() is a historical leftover without\n> any functional requirement.\n> \n> Use ktime_get() instead.\n\nThe subject line says \"Use sched_clock() ...\", but the implementation\nactually uses ktime_get(). Is it a typo or anything I misunderstood?\n\nOther parts look good to me,\n\nReviewed-by: Lu Baolu \n\n> \n> Signed-off-by: Thomas Gleixner\n> Cc:x86@kernel.org\n> Cc: Lu Baolu\n> Cc:iommu@lists.linux.dev\n> ---\n> arch/x86/include/asm/iommu.h | 3 ---\n> drivers/iommu/intel/dmar.c | 4 ++--\n> drivers/iommu/intel/iommu.h | 8 ++++++--\n> 3 files changed, 8 insertions(+), 7 deletions(-)\n\nThanks,\nbaolu","headers":{"Return-Path":"\n ","X-Original-To":["incoming@patchwork.ozlabs.org","linuxppc-dev@lists.ozlabs.org"],"Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256\n header.s=Intel header.b=FEXiIzJv;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=lists.ozlabs.org\n (client-ip=112.213.38.117; helo=lists.ozlabs.org;\n envelope-from=linuxppc-dev+bounces-19611-incoming=patchwork.ozlabs.org@lists.ozlabs.org;\n receiver=patchwork.ozlabs.org)","lists.ozlabs.org;\n arc=none smtp.remote-ip=192.198.163.10","lists.ozlabs.org;\n dmarc=pass (p=none dis=none) header.from=linux.intel.com","lists.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256\n header.s=Intel header.b=FEXiIzJv;\n\tdkim-atps=neutral","lists.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=linux.intel.com\n (client-ip=192.198.163.10; 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a=\"88229179\"","E=Sophos;i=\"6.23,171,1770624000\";\n d=\"scan'208\";a=\"88229179\"","E=Sophos;i=\"6.23,171,1770624000\";\n d=\"scan'208\";a=\"225932507\""],"X-ExtLoop1":"1","Message-ID":"<9db9515b-08e8-47bd-aced-206ac183195a@linux.intel.com>","Date":"Fri, 10 Apr 2026 21:45:43 +0800","X-Mailing-List":"linuxppc-dev@lists.ozlabs.org","List-Id":"","List-Help":"","List-Owner":"","List-Post":"","List-Archive":",\n ","List-Subscribe":",\n ,\n ","List-Unsubscribe":"","Precedence":"list","MIME-Version":"1.0","User-Agent":"Mozilla Thunderbird","Cc":"baolu.lu@linux.intel.com, x86@kernel.org, iommu@lists.linux.dev,\n Arnd Bergmann , Michael Grzeschik\n , netdev@vger.kernel.org,\n linux-wireless@vger.kernel.org, Herbert Xu ,\n linux-crypto@vger.kernel.org, Vlastimil Babka ,\n linux-mm@kvack.org, David Woodhouse ,\n Bernie Thompson , linux-fbdev@vger.kernel.org,\n Theodore Tso , linux-ext4@vger.kernel.org,\n Andrew Morton ,\n Uladzislau Rezki , Marco Elver ,\n Dmitry Vyukov , kasan-dev@googlegroups.com,\n Andrey Ryabinin ,\n Thomas Sailer , linux-hams@vger.kernel.org,\n \"Jason A. Donenfeld\" ,\n Richard Henderson ,\n linux-alpha@vger.kernel.org, Russell King ,\n linux-arm-kernel@lists.infradead.org,\n Catalin Marinas ,\n Huacai Chen , loongarch@lists.linux.dev,\n Geert Uytterhoeven , linux-m68k@lists.linux-m68k.org,\n Dinh Nguyen , Jonas Bonn ,\n linux-openrisc@vger.kernel.org, Helge Deller ,\n linux-parisc@vger.kernel.org, Michael Ellerman ,\n linuxppc-dev@lists.ozlabs.org, Paul Walmsley ,\n linux-riscv@lists.infradead.org, Heiko Carstens ,\n linux-s390@vger.kernel.org, \"David S. Miller\" ,\n sparclinux@vger.kernel.org","Subject":"Re: [patch 09/38] iommu/vt-d: Use sched_clock() instead of\n get_cycles()","To":"Thomas Gleixner , LKML ","References":"<20260410120044.031381086@kernel.org>\n <20260410120318.187521447@kernel.org>","Content-Language":"en-US","From":"Baolu Lu ","In-Reply-To":"<20260410120318.187521447@kernel.org>","Content-Type":"text/plain; charset=UTF-8; format=flowed","Content-Transfer-Encoding":"7bit","X-Spam-Status":"No, score=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED,\n\tDKIM_VALID,RCVD_IN_DNSWL_MED,SPF_HELO_NONE,SPF_PASS autolearn=disabled\n\tversion=4.0.1 OzLabs 8","X-Spam-Checker-Version":"SpamAssassin 4.0.1 (2024-03-25) on lists.ozlabs.org"}},{"id":3675928,"web_url":"http://patchwork.ozlabs.org/comment/3675928/","msgid":"<87y0iuzw3r.ffs@tglx>","date":"2026-04-10T15:14:00","subject":"Re: [patch 09/38] iommu/vt-d: Use sched_clock() instead of\n get_cycles()","submitter":{"id":92397,"url":"http://patchwork.ozlabs.org/api/people/92397/","name":"Thomas Gleixner","email":"tglx@kernel.org"},"content":"On Fri, Apr 10 2026 at 21:45, Baolu Lu wrote:\n> On 4/10/2026 8:19 PM, Thomas Gleixner wrote:\n>> Calculating the timeout from get_cycles() is a historical leftover without\n>> any functional requirement.\n>> \n>> Use ktime_get() instead.\n>\n> The subject line says \"Use sched_clock() ...\", but the implementation\n> actually uses ktime_get(). Is it a typo or anything I misunderstood?\n\nIndeed. Leftover from an earlier version.\n\nThanks,\n\n tglx","headers":{"Return-Path":"\n ","X-Original-To":["incoming@patchwork.ozlabs.org","linuxppc-dev@lists.ozlabs.org"],"Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256\n header.s=k20201202 header.b=DQRfv3hP;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=lists.ozlabs.org\n (client-ip=2404:9400:21b9:f100::1; helo=lists.ozlabs.org;\n envelope-from=linuxppc-dev+bounces-19612-incoming=patchwork.ozlabs.org@lists.ozlabs.org;\n receiver=patchwork.ozlabs.org)","lists.ozlabs.org;\n arc=none smtp.remote-ip=172.234.252.31","lists.ozlabs.org;\n dmarc=pass (p=quarantine dis=none) header.from=kernel.org","lists.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256\n header.s=k20201202 header.b=DQRfv3hP;\n\tdkim-atps=neutral","lists.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org\n (client-ip=172.234.252.31; 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lists.ozlabs.org;\n dmarc=pass (p=quarantine dis=none) header.from=kernel.org;\n dkim=pass (2048-bit key;\n unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256\n header.s=k20201202 header.b=DQRfv3hP; dkim-atps=neutral;\n spf=pass (client-ip=172.234.252.31; helo=sea.source.kernel.org;\n envelope-from=tglx@kernel.org;\n receiver=lists.ozlabs.org) smtp.mailfrom=kernel.org","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org;\n\ts=k20201202; t=1775834044;\n\tbh=ZX44VkA/oGGdYrqGVtHG3BQ09eU0s5TAD8UsmKEvOJ4=;\n\th=From:To:Cc:Subject:In-Reply-To:References:Date:From;\n\tb=DQRfv3hPFw/TKa/ZakF0C/CvhlLPEsVqQv+2r4uwxdObvOGMMWr2s346gixb/wzYP\n\t kH3jI1VGrMbPCg8bbeliLsWsv0WorMVV9pr65pzZbqt3ANfLMAZ3WpCzHo7EbPC0aw\n\t sFqvG5W5Zh5Zl9hqpd/S10vk3SPDt4AvvXdP7MWFAVnJ1yy95RtrFN5r3P/n0YzraC\n\t K1ddeqgVvP6yW3cqrHOPD+5bbhJuKzxhUEtkBkREvZCz2D1PF358eBsZtX1OaLotF8\n\t mIrAdKqmlNIgawRmNAF5mT5jG8tytmCXBJPCuscrYjON8tMw7soKn19X1CoLhvhPBR\n\t sIA/Sxe0F1CKA==","From":"Thomas Gleixner ","To":"Baolu Lu , LKML ","Cc":"baolu.lu@linux.intel.com, x86@kernel.org, iommu@lists.linux.dev, Arnd\n Bergmann , Michael Grzeschik ,\n netdev@vger.kernel.org, linux-wireless@vger.kernel.org, Herbert Xu\n , linux-crypto@vger.kernel.org, Vlastimil\n Babka , linux-mm@kvack.org, David Woodhouse\n , Bernie Thompson ,\n linux-fbdev@vger.kernel.org, Theodore Tso ,\n linux-ext4@vger.kernel.org, Andrew Morton ,\n Uladzislau Rezki , Marco Elver ,\n Dmitry Vyukov , kasan-dev@googlegroups.com, Andrey\n Ryabinin , Thomas Sailer\n , linux-hams@vger.kernel.org, \"Jason A.\n Donenfeld\" , Richard Henderson\n , linux-alpha@vger.kernel.org, Russell King\n , linux-arm-kernel@lists.infradead.org, Catalin\n Marinas , Huacai Chen ,\n loongarch@lists.linux.dev, Geert Uytterhoeven ,\n linux-m68k@lists.linux-m68k.org, Dinh Nguyen , Jonas\n Bonn , linux-openrisc@vger.kernel.org, Helge Deller\n , linux-parisc@vger.kernel.org, Michael Ellerman\n , linuxppc-dev@lists.ozlabs.org, Paul Walmsley\n , linux-riscv@lists.infradead.org, Heiko Carstens\n , linux-s390@vger.kernel.org, \"David S. Miller\"\n , sparclinux@vger.kernel.org","Subject":"Re: [patch 09/38] iommu/vt-d: Use sched_clock() instead of\n get_cycles()","In-Reply-To":"<9db9515b-08e8-47bd-aced-206ac183195a@linux.intel.com>","References":"<20260410120044.031381086@kernel.org>\n <20260410120318.187521447@kernel.org>\n <9db9515b-08e8-47bd-aced-206ac183195a@linux.intel.com>","Date":"Fri, 10 Apr 2026 17:14:00 +0200","Message-ID":"<87y0iuzw3r.ffs@tglx>","X-Mailing-List":"linuxppc-dev@lists.ozlabs.org","List-Id":"","List-Help":"","List-Owner":"","List-Post":"","List-Archive":",\n ","List-Subscribe":",\n ,\n ","List-Unsubscribe":"","Precedence":"list","MIME-Version":"1.0","Content-Type":"text/plain","X-Spam-Status":"No, score=-0.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED,\n\tDKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_NONE,SPF_PASS\n\tautolearn=disabled version=4.0.1 OzLabs 8","X-Spam-Checker-Version":"SpamAssassin 4.0.1 (2024-03-25) on lists.ozlabs.org"}}]