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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7F6C9C021A0 for ; Thu, 13 Feb 2025 22:55:10 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 1E7E3280017; Thu, 13 Feb 2025 17:55:10 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 197CF280016; Thu, 13 Feb 2025 17:55:10 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0380B280017; Thu, 13 Feb 2025 17:55:09 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id D2610280016 for ; Thu, 13 Feb 2025 17:55:09 -0500 (EST) Received: from smtpin25.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 85835161848 for ; Thu, 13 Feb 2025 22:55:09 +0000 (UTC) X-FDA: 83116428738.25.E8B2CF7 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.9]) by imf07.hostedemail.com (Postfix) with ESMTP id 3950A40005 for ; Thu, 13 Feb 2025 22:55:07 +0000 (UTC) Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=Y+zIwHjB; dmarc=pass (policy=none) header.from=intel.com; spf=pass (imf07.hostedemail.com: domain of dave.hansen@intel.com designates 198.175.65.9 as permitted sender) smtp.mailfrom=dave.hansen@intel.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1739487307; a=rsa-sha256; cv=none; b=GJyzLyD03t46c3LcH6KKvwtdMrKIABqGgS16IIIFtuC2Qjakth9sLHu4KTgoLu0sF8DM6g NG0idtz8TciUsizuF6I7HPwmDGeShGo6UdonKgI3V8SAoeh3Yjt7u0GbPmz1c/LF0GeSce ZepoYNv2PzSYeOyy9kgWh1o1OaLdYRI= ARC-Authentication-Results: i=1; imf07.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=Y+zIwHjB; dmarc=pass (policy=none) header.from=intel.com; spf=pass (imf07.hostedemail.com: domain of dave.hansen@intel.com designates 198.175.65.9 as permitted sender) smtp.mailfrom=dave.hansen@intel.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1739487307; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=Sf+szxcLhUShr8ExPqZm//DpiJcQJVJQpR7VswJv8CM=; b=Zg8YHRIKVxhpgO7qObhWVPliegOGIDaaqQjnkFrmBYtemnXuKCyN4cZdCjGAVVBcUP+XzL UxXyMLexDHqDxRxjfX33ykUp08r/T1seNIdg35wbqC86E1JcteYVyU1VfSF5Ku90lAsfda brNypVx5Cj6DPQQ/pOktSflMdPmZLbY= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1739487307; x=1771023307; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=Sf+szxcLhUShr8ExPqZm//DpiJcQJVJQpR7VswJv8CM=; b=Y+zIwHjByD1k7Wy4CYsy2QLd8gEz9nl85CBSyPkKZwKkD+MCnt6HzMX2 dwzjkiU40FwKZaCdLqau84vFugdb/aNOpDL/opx2sMQ1rrJyZaZYbJgku 7+nBm6iII28K+1qBuYlyALRTUvLK5trAKZZ/Yoqm9PizjD/Y7Jl42o2M9 S43geZIkXSvUBqnH4Bpy1DlliqgnEOrFgcqJwePHPmEqEFnLdTswiEAm3 JWwQBtTWzk0x/x3G+ti2S2SkgrbJHF9h7Jf7qINRpxZDrVuHXVGqGKG/H S3kGnMnRfmzrpUGUkjFCDbwC4LxlMWsu0vkeaz6u38K17bnFlnVx8iBp2 Q==; X-CSE-ConnectionGUID: x3cOwSTqTgqCy2qrtA6yeQ== X-CSE-MsgGUID: FhhxFhDrQ22AfPCr+8z0GA== X-IronPort-AV: E=McAfee;i="6700,10204,11344"; a="62685104" X-IronPort-AV: E=Sophos;i="6.13,284,1732608000"; d="scan'208";a="62685104" Received: from fmviesa006.fm.intel.com ([10.60.135.146]) by orvoesa101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Feb 2025 14:54:46 -0800 X-CSE-ConnectionGUID: FS1avYeUQg+Mej+JGS0Ibg== X-CSE-MsgGUID: ACPBrnOsSFWv83/VzOzbpg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.13,284,1732608000"; d="scan'208";a="113164091" Received: from iherna2-mobl4.amr.corp.intel.com (HELO [10.125.108.188]) ([10.125.108.188]) by fmviesa006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Feb 2025 14:54:45 -0800 Message-ID: <38c424bd-8f49-466a-b414-93a45a7ee3ec@intel.com> Date: Thu, 13 Feb 2025 14:54:44 -0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH RESEND 1/2] x86/locking: Use ALT_OUTPUT_SP() for percpu_{,try_}cmpxchg{64,128}_op() To: Uros Bizjak Cc: x86@kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Dennis Zhou , Tejun Heo , Christoph Lameter , "Peter Zijlstra (Intel)" References: <20250213191457.12377-1-ubizjak@gmail.com> <04adffd9-2900-4cdb-a557-1c486a87b522@intel.com> From: Dave Hansen Content-Language: en-US Autocrypt: addr=dave.hansen@intel.com; keydata= xsFNBE6HMP0BEADIMA3XYkQfF3dwHlj58Yjsc4E5y5G67cfbt8dvaUq2fx1lR0K9h1bOI6fC oAiUXvGAOxPDsB/P6UEOISPpLl5IuYsSwAeZGkdQ5g6m1xq7AlDJQZddhr/1DC/nMVa/2BoY 2UnKuZuSBu7lgOE193+7Uks3416N2hTkyKUSNkduyoZ9F5twiBhxPJwPtn/wnch6n5RsoXsb ygOEDxLEsSk/7eyFycjE+btUtAWZtx+HseyaGfqkZK0Z9bT1lsaHecmB203xShwCPT49Blxz VOab8668QpaEOdLGhtvrVYVK7x4skyT3nGWcgDCl5/Vp3TWA4K+IofwvXzX2ON/Mj7aQwf5W iC+3nWC7q0uxKwwsddJ0Nu+dpA/UORQWa1NiAftEoSpk5+nUUi0WE+5DRm0H+TXKBWMGNCFn c6+EKg5zQaa8KqymHcOrSXNPmzJuXvDQ8uj2J8XuzCZfK4uy1+YdIr0yyEMI7mdh4KX50LO1 pmowEqDh7dLShTOif/7UtQYrzYq9cPnjU2ZW4qd5Qz2joSGTG9eCXLz5PRe5SqHxv6ljk8mb ApNuY7bOXO/A7T2j5RwXIlcmssqIjBcxsRRoIbpCwWWGjkYjzYCjgsNFL6rt4OL11OUF37wL QcTl7fbCGv53KfKPdYD5hcbguLKi/aCccJK18ZwNjFhqr4MliQARAQABzUVEYXZpZCBDaHJp c3RvcGhlciBIYW5zZW4gKEludGVsIFdvcmsgQWRkcmVzcykgPGRhdmUuaGFuc2VuQGludGVs LmNvbT7CwXgEEwECACIFAlQ+9J0CGwMGCwkIBwMCBhUIAgkKCwQWAgMBAh4BAheAAAoJEGg1 lTBwyZKwLZUP/0dnbhDc229u2u6WtK1s1cSd9WsflGXGagkR6liJ4um3XCfYWDHvIdkHYC1t MNcVHFBwmQkawxsYvgO8kXT3SaFZe4ISfB4K4CL2qp4JO+nJdlFUbZI7cz/Td9z8nHjMcWYF IQuTsWOLs/LBMTs+ANumibtw6UkiGVD3dfHJAOPNApjVr+M0P/lVmTeP8w0uVcd2syiaU5jB aht9CYATn+ytFGWZnBEEQFnqcibIaOrmoBLu2b3fKJEd8Jp7NHDSIdrvrMjYynmc6sZKUqH2 I1qOevaa8jUg7wlLJAWGfIqnu85kkqrVOkbNbk4TPub7VOqA6qG5GCNEIv6ZY7HLYd/vAkVY E8Plzq/NwLAuOWxvGrOl7OPuwVeR4hBDfcrNb990MFPpjGgACzAZyjdmYoMu8j3/MAEW4P0z F5+EYJAOZ+z212y1pchNNauehORXgjrNKsZwxwKpPY9qb84E3O9KYpwfATsqOoQ6tTgr+1BR CCwP712H+E9U5HJ0iibN/CDZFVPL1bRerHziuwuQuvE0qWg0+0SChFe9oq0KAwEkVs6ZDMB2 P16MieEEQ6StQRlvy2YBv80L1TMl3T90Bo1UUn6ARXEpcbFE0/aORH/jEXcRteb+vuik5UGY 5TsyLYdPur3TXm7XDBdmmyQVJjnJKYK9AQxj95KlXLVO38lczsFNBFRjzmoBEACyAxbvUEhd GDGNg0JhDdezyTdN8C9BFsdxyTLnSH31NRiyp1QtuxvcqGZjb2trDVuCbIzRrgMZLVgo3upr MIOx1CXEgmn23Zhh0EpdVHM8IKx9Z7V0r+rrpRWFE8/wQZngKYVi49PGoZj50ZEifEJ5qn/H Nsp2+Y+bTUjDdgWMATg9DiFMyv8fvoqgNsNyrrZTnSgoLzdxr89FGHZCoSoAK8gfgFHuO54B lI8QOfPDG9WDPJ66HCodjTlBEr/Cwq6GruxS5i2Y33YVqxvFvDa1tUtl+iJ2SWKS9kCai2DR 3BwVONJEYSDQaven/EHMlY1q8Vln3lGPsS11vSUK3QcNJjmrgYxH5KsVsf6PNRj9mp8Z1kIG qjRx08+nnyStWC0gZH6NrYyS9rpqH3j+hA2WcI7De51L4Rv9pFwzp161mvtc6eC/GxaiUGuH BNAVP0PY0fqvIC68p3rLIAW3f97uv4ce2RSQ7LbsPsimOeCo/5vgS6YQsj83E+AipPr09Caj 0hloj+hFoqiticNpmsxdWKoOsV0PftcQvBCCYuhKbZV9s5hjt9qn8CE86A5g5KqDf83Fxqm/ vXKgHNFHE5zgXGZnrmaf6resQzbvJHO0Fb0CcIohzrpPaL3YepcLDoCCgElGMGQjdCcSQ+Ci FCRl0Bvyj1YZUql+ZkptgGjikQARAQABwsFfBBgBAgAJBQJUY85qAhsMAAoJEGg1lTBwyZKw l4IQAIKHs/9po4spZDFyfDjunimEhVHqlUt7ggR1Hsl/tkvTSze8pI1P6dGp2XW6AnH1iayn yRcoyT0ZJ+Zmm4xAH1zqKjWplzqdb/dO28qk0bPso8+1oPO8oDhLm1+tY+cOvufXkBTm+whm +AyNTjaCRt6aSMnA/QHVGSJ8grrTJCoACVNhnXg/R0g90g8iV8Q+IBZyDkG0tBThaDdw1B2l asInUTeb9EiVfL/Zjdg5VWiF9LL7iS+9hTeVdR09vThQ/DhVbCNxVk+DtyBHsjOKifrVsYep WpRGBIAu3bK8eXtyvrw1igWTNs2wazJ71+0z2jMzbclKAyRHKU9JdN6Hkkgr2nPb561yjcB8 sIq1pFXKyO+nKy6SZYxOvHxCcjk2fkw6UmPU6/j/nQlj2lfOAgNVKuDLothIxzi8pndB8Jju KktE5HJqUUMXePkAYIxEQ0mMc8Po7tuXdejgPMwgP7x65xtfEqI0RuzbUioFltsp1jUaRwQZ MTsCeQDdjpgHsj+P2ZDeEKCbma4m6Ez/YWs4+zDm1X8uZDkZcfQlD9NldbKDJEXLIjYWo1PH hYepSffIWPyvBMBTW2W5FRjJ4vLRrJSUoEfJuPQ3vW9Y73foyo/qFoURHO48AinGPZ7PC7TF vUaNOTjKedrqHkaOcqB185ahG2had0xnFsDPlx5y In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 3950A40005 X-Stat-Signature: 367appde9ootfzhrp3hq8dodmm54t4o7 X-Rspam-User: X-HE-Tag: 1739487307-674844 X-HE-Meta: U2FsdGVkX1/ZHCAFA6NhQv+XCWYfYJd2Yrk7/mihuMdMnuownk9We6q+CLtb7HyxxCOc9ecBDQq1nT0lrtm7doqviaNgAtvk5LVtNuHmKEKEYI6f6yKHDtRm1k24euKxrhrYqNtY50DSFsu63gnGX+YiGJC1ztDDTd5T8m7HG+q3fRc0hh3iQzjceSaR8pV01kiL8srKvfZLb0Jnv6L7He8Ex2JPBKl4eXm0MArTb8pWX5edlPbdyTZVZpluI0dkizxZ8ZSsE/ZIi1Hcn3U5S2yFgiDbsbYP4ykgxonAhgncbCpfjmgTiuZ6oqRxPjhweRqxm1vvZqhwRKPWtL7v3jsEXT63u4ib4B6bwgVRreSibAvqix8mHZ1M3QMogQ+5jgyRdBd7zz2ryDkNaoRPuRH29HaAZZj826/HADOauOlfTcSPmpLUVNvIMWk4xuFStin7vYqO/pIkrlx/UNQ17U4jNz7z9vuW3DXarPrgVMdO7knOAJxJ9Ea/FaTTdCo8InjhIPQ8jYlQ+zCZU3DxRqWOcF5uw+VSBNqV/YznyZ5xA7PPqHVbdqJR1Z89CPxoKKT0OKTha59BQSzB9cPh6YZ4ha0e2Lum8my1uC/Ej8jrTeG/xxmfmTRzXIs72YV0usfYa5PXQDu/vuzVyjpBKIfK1HVoOh/vv/uxmr9VRX72QDJnv1DzOBn7B7EZpgfNni+Fo24uJtLZoL6cu5IG9XFy4YGWZCC9WSBREbPvhVwwPMNmscx3Figs4lQGQVx+/iBbDFim6g1T7/LGXqDt/RnfOIQw/Zm29ZxvLNs6XoFlIxYEupGvSkHhtF/zCGMqEflbMKijJBQ8smsOQ8OQ8SyKj/dxC+bmCeOuLemme+HGNAjULBLl1YjimqFn1mic+X3IpJwIdjnT1Amw1QPLKyQohBa8wIo7S31gTHGyaDXZsivBWgV3MBm/D0p/ov1XcmHC+U2BTohd4l0byHs ZMiDsV3S 37nAy9BLoNLkxzVWScHGdb973ly8PcyHvMYkofybPSOLmTQEFsPgULg5Uf/cVqOA3R5OV5QV+HHqfXSoLh2ebFiS3YSelSUNA8Ui14nH5O7bki9cKfM51j8aqXQs2jDxx0oGbiPZBOwJdsJLmO0sJYGaDisvxtq0WtJBAR/aDKSfUp90JILBzPv3XXjzN3vH1nFG6kbou6mPHRDH8yoxl7lCzETTkItLUgiJpxNxoHI7CW5JmAgWC2YT/rg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 2/13/25 13:17, Uros Bizjak wrote: >> Basically, you've told me what the patch does, but not why anyone should >> care or why it should be applied. > This is actually explained at length in the comment for > ASM_CALL_CONSTRAINT, which ALT_OUTPUT_SP macro uses. Great info, thanks! Could you give the patch another shot and include this in the changelog, please? Better yet, you could paraphrase the comment so that we don't have to go searching for it.