From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.9]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 31CDE27605B for ; Thu, 6 Mar 2025 22:00:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.9 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741298432; cv=none; b=klF87GMpfHpWMvSOWbJlg5CYM4unHw8su6r+u+wAWV3idkk5MCnKqSS6fN1CKEAwUqNGvgoY9xit7xmjQ+1yFEKUcqCYj2mD+XXg1aBrWWmUaAmIUbvVWU+G0IgOkZFuVk5BpwG20rGMNyzlfStYwChcqRgEgM/d7GcZqlb1f4c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741298432; c=relaxed/simple; bh=h9M//6a54qcUwRZ9pPr7/OWIx8Cbbr/ZQonhNJvLioI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=LiwDhzfWbdBSxsvZ1vNpw9pXdda6DFKKD//XT7G+znMNouyVZjv6OMYPwW81PVrAKusOduJDwb7uIW8CTWt7bSY3HJIWteaEN4SvUenLTan7HPbminM0HvHHTz+loRyBZZ/5mzJph0DUO2SRzwCGz2KFgNsiItay86t2lzN3XH4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=RMoLlFNa; arc=none smtp.client-ip=192.198.163.9 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="RMoLlFNa" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1741298431; x=1772834431; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=h9M//6a54qcUwRZ9pPr7/OWIx8Cbbr/ZQonhNJvLioI=; b=RMoLlFNaTDykroOFU9RgZkwSx6bZ5H09AcChN/g42KLcUl7CvkjAae+p yFZATxSbSKr50HlGl6ghl4B1HmskifbIRuDliozLZNRAw8b3YMlVftFZS BJqFmhLnkMwelKKnY9SOrGPbsFHbONKSm44rq1KwHDj5DRNNHdPb6+Ght wHFkHmIyh4idAZv/BIY8p04vEAcKW9akIMCeJNDmtlTAhJ1cFxc1Dzvsz UeVjrckLLVkqo/rthm1GM4oO3cSd+6yrc1HlvSEPD3/LY96/U2oMJRS19 Yb6j2wzN6ay0XD66XKfkioY1gzhz+1fvTLZHfZlbOwTNzDKrcf77tvBXo Q==; X-CSE-ConnectionGUID: roRUH8gMQzSLtg5UrGwAsw== X-CSE-MsgGUID: XY4FGe4sRQyyXV1aTIVC6A== X-IronPort-AV: E=McAfee;i="6700,10204,11365"; a="52974390" X-IronPort-AV: E=Sophos;i="6.14,227,1736841600"; d="scan'208";a="52974390" Received: from orviesa005.jf.intel.com ([10.64.159.145]) by fmvoesa103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Mar 2025 14:00:30 -0800 X-CSE-ConnectionGUID: ochOd0YvQ5e1u5hCabolMg== X-CSE-MsgGUID: w7Xsev9MQoOpoR8PhhxYMQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.12,224,1728975600"; d="scan'208";a="124347486" Received: from kinlongk-mobl1.amr.corp.intel.com (HELO [10.125.110.90]) ([10.125.110.90]) by orviesa005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Mar 2025 14:00:30 -0800 Message-ID: <0ada12f8-4fdb-4dad-90f7-b044993e829c@intel.com> Date: Thu, 6 Mar 2025 14:00:52 -0800 Precedence: bulk X-Mailing-List: x86-cpuid@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v1 07/12] tools/x86/kcpuid: Add rudimentary CPU vendor detection To: "Ahmed S. Darwish" , Borislav Petkov , Ingo Molnar , Dave Hansen Cc: Thomas Gleixner , Andrew Cooper , "H. Peter Anvin" , x86@kernel.org, John Ogness , x86-cpuid@lists.linux.dev, LKML References: <20250306205000.227399-1-darwi@linutronix.de> <20250306205000.227399-8-darwi@linutronix.de> 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: <20250306205000.227399-8-darwi@linutronix.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 3/6/25 12:49, Ahmed S. Darwish wrote: > +/* > + * Leaf 0x0 EDX output, CPU vendor ID string bytes 4 - 7. > + */ > +enum { > + EDX_INTEL = fourcc('i', 'n', 'e', 'I'), /* Genu_ineI_ntel */ > + EDX_AMD = fourcc('e', 'n', 't', 'i'), /* Auth_enti_cAMD */ > + EDX_HYGON = fourcc('n', 'G', 'e', 'n'), /* Hygo_nGen_uine */ > + EDX_TRANSMETA = fourcc('i', 'n', 'e', 'T'), /* Genu_ineT_Mx86 */ > + EDX_CENTAUR = fourcc('a', 'u', 'r', 'H'), /* Cent_aurH_auls */ > + EDX_ZHAOXIN = fourcc('a', 'n', 'g', 'h'), /* Sh_angh_ai */ > +}; So, this is cute and all. But isn't it a _wee_ bit too clever for its own good? Why not just have a dumb array: { INTEL, "GenuineIntel" }, { AMD, "AuthenticAMD" ], ... Are we really looking to save a few dozen CPU cycles in this thing? It took me at least a minute or two of staring at this thing to figure out what the heck it was doing.