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 lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C616DC5472F for ; Tue, 27 Aug 2024 14:33:09 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.784122.1193515 (Exim 4.92) (envelope-from ) id 1sixFV-0007nu-6e; Tue, 27 Aug 2024 14:32:45 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 784122.1193515; Tue, 27 Aug 2024 14:32:45 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1sixFV-0007nn-3b; Tue, 27 Aug 2024 14:32:45 +0000 Received: by outflank-mailman (input) for mailman id 784122; Tue, 27 Aug 2024 14:32:43 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1sixFT-0007nh-Ba for xen-devel@lists.xenproject.org; Tue, 27 Aug 2024 14:32:43 +0000 Received: from mail-ej1-x62b.google.com (mail-ej1-x62b.google.com [2a00:1450:4864:20::62b]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 372ca944-6481-11ef-99a0-01e77a169b0f; Tue, 27 Aug 2024 16:32:41 +0200 (CEST) Received: by mail-ej1-x62b.google.com with SMTP id a640c23a62f3a-a86859e2fc0so692647366b.3 for ; Tue, 27 Aug 2024 07:32:41 -0700 (PDT) Received: from [10.125.226.166] ([185.25.67.249]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a86e594e815sm116071666b.197.2024.08.27.07.32.39 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 27 Aug 2024 07:32:39 -0700 (PDT) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 372ca944-6481-11ef-99a0-01e77a169b0f DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=citrix.com; s=google; t=1724769161; x=1725373961; darn=lists.xenproject.org; h=content-transfer-encoding:in-reply-to:autocrypt:content-language :references:cc:to:from:subject:user-agent:mime-version:date :message-id:from:to:cc:subject:date:message-id:reply-to; bh=bX3yhpUS8Udc/Fy86+W8abe82JJZNRwGknibPZYS9ZM=; b=LvhbalI8/mute3KW2RfZispzJxNrRgJiRJ3JYKKXdoMI2M+Yi6BRD/4MJpyGdANUfc 9I3wHfYN4Io8jAQbOLZoNYa+YC6dvaDc1rGpIfpD6LIcHR/sLYrifMD1vy6D20VQ8T2d pE/3KLIPMInHVjrsRTRV/CkHUvZQmGCsV5O/Q= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1724769161; x=1725373961; h=content-transfer-encoding:in-reply-to:autocrypt:content-language :references:cc:to:from:subject:user-agent:mime-version:date :message-id:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=bX3yhpUS8Udc/Fy86+W8abe82JJZNRwGknibPZYS9ZM=; b=oE5CSdmzm96RvT4P7p0VY/cF0PYLX7Ys/i/ivIF5IaL8HdL02UPMsee/DCWzt9RxK2 /EqtkUA5g1p2yFdbDYdhzxrx5Dk/3dZT8YMivboZhkAMWbaSAQBB4gDRM84/Y29WmPtR iew/eyLcGj70Sb0jVZ8+UWKD2wUlaakBgf07i2mogand8/Hja6TE6JlGfVi5VzkLDqy9 ZaH7oQWpxefy3jvh66JkVHHjdBhtEJ+AbQm2G00nLVUlG+3fdLPyBGmeNlTlPBH0d6M5 0ys0kqfmm2sRwnu98Pok+kWobplJeH2v75vuDZWkijlfrDJ54Tc0AH9lfz5iMkFhrZqT XGMw== X-Forwarded-Encrypted: i=1; AJvYcCXYHReyfMlHtgt5c47KKsoDAKN9J/x9zwuqTQB6P3xWv1xhIGo2jreIO8AGYQAcuCaA6KaZMVmeyDg=@lists.xenproject.org X-Gm-Message-State: AOJu0YzcMjKKQr46lXvTTvnmktEnbtlPj3jZxNE1nNUOm7Q6R+Pn10Qf HDuGxVGyHNODfTlK683iE1ugm/ajPA5FEwJwG18axsinpNBDi+Jhtcirmr3b7Lk= X-Google-Smtp-Source: AGHT+IFzjnQ51A8bA7YNUS0a9rbS5W7qBsYr2TXf3NM7pT6g7gpdVYlQoaMygPBlDN/RJSTobPo6MA== X-Received: by 2002:a17:906:6a23:b0:a7a:8e98:890d with SMTP id a640c23a62f3a-a86e39c9e11mr261384566b.16.1724769160253; Tue, 27 Aug 2024 07:32:40 -0700 (PDT) Message-ID: Date: Tue, 27 Aug 2024 15:32:38 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 7/9] xen/bitops: Implement hweight64() in terms of hweightl() From: Andrew Cooper To: Jan Beulich Cc: =?UTF-8?Q?Roger_Pau_Monn=C3=A9?= , Wei Liu , Stefano Stabellini , Julien Grall , Volodymyr Babchuk , Bertrand Marquis , Michal Orzel , Oleksii Kurochko , Shawn Anastasio , Xen-devel References: <20240822230635.954557-1-andrew.cooper3@citrix.com> <20240822230635.954557-8-andrew.cooper3@citrix.com> <11da1350-095f-49c8-bdf0-f5c83e9f0d39@suse.com> <70047ef7-ca22-4eeb-9510-09ccdf0871c0@citrix.com> <73309650-3912-418b-b2e6-a60676519911@suse.com> Content-Language: en-GB Autocrypt: addr=andrew.cooper3@citrix.com; keydata= xsFNBFLhNn8BEADVhE+Hb8i0GV6mihnnr/uiQQdPF8kUoFzCOPXkf7jQ5sLYeJa0cQi6Penp VtiFYznTairnVsN5J+ujSTIb+OlMSJUWV4opS7WVNnxHbFTPYZVQ3erv7NKc2iVizCRZ2Kxn srM1oPXWRic8BIAdYOKOloF2300SL/bIpeD+x7h3w9B/qez7nOin5NzkxgFoaUeIal12pXSR Q354FKFoy6Vh96gc4VRqte3jw8mPuJQpfws+Pb+swvSf/i1q1+1I4jsRQQh2m6OTADHIqg2E ofTYAEh7R5HfPx0EXoEDMdRjOeKn8+vvkAwhviWXTHlG3R1QkbE5M/oywnZ83udJmi+lxjJ5 YhQ5IzomvJ16H0Bq+TLyVLO/VRksp1VR9HxCzItLNCS8PdpYYz5TC204ViycobYU65WMpzWe LFAGn8jSS25XIpqv0Y9k87dLbctKKA14Ifw2kq5OIVu2FuX+3i446JOa2vpCI9GcjCzi3oHV e00bzYiHMIl0FICrNJU0Kjho8pdo0m2uxkn6SYEpogAy9pnatUlO+erL4LqFUO7GXSdBRbw5 gNt25XTLdSFuZtMxkY3tq8MFss5QnjhehCVPEpE6y9ZjI4XB8ad1G4oBHVGK5LMsvg22PfMJ ISWFSHoF/B5+lHkCKWkFxZ0gZn33ju5n6/FOdEx4B8cMJt+cWwARAQABzSlBbmRyZXcgQ29v cGVyIDxhbmRyZXcuY29vcGVyM0BjaXRyaXguY29tPsLBegQTAQgAJAIbAwULCQgHAwUVCgkI CwUWAgMBAAIeAQIXgAUCWKD95wIZAQAKCRBlw/kGpdefoHbdD/9AIoR3k6fKl+RFiFpyAhvO 59ttDFI7nIAnlYngev2XUR3acFElJATHSDO0ju+hqWqAb8kVijXLops0gOfqt3VPZq9cuHlh IMDquatGLzAadfFx2eQYIYT+FYuMoPZy/aTUazmJIDVxP7L383grjIkn+7tAv+qeDfE+txL4 SAm1UHNvmdfgL2/lcmL3xRh7sub3nJilM93RWX1Pe5LBSDXO45uzCGEdst6uSlzYR/MEr+5Z JQQ32JV64zwvf/aKaagSQSQMYNX9JFgfZ3TKWC1KJQbX5ssoX/5hNLqxMcZV3TN7kU8I3kjK mPec9+1nECOjjJSO/h4P0sBZyIUGfguwzhEeGf4sMCuSEM4xjCnwiBwftR17sr0spYcOpqET ZGcAmyYcNjy6CYadNCnfR40vhhWuCfNCBzWnUW0lFoo12wb0YnzoOLjvfD6OL3JjIUJNOmJy RCsJ5IA/Iz33RhSVRmROu+TztwuThClw63g7+hoyewv7BemKyuU6FTVhjjW+XUWmS/FzknSi dAG+insr0746cTPpSkGl3KAXeWDGJzve7/SBBfyznWCMGaf8E2P1oOdIZRxHgWj0zNr1+ooF /PzgLPiCI4OMUttTlEKChgbUTQ+5o0P080JojqfXwbPAyumbaYcQNiH1/xYbJdOFSiBv9rpt TQTBLzDKXok86M7BTQRS4TZ/ARAAkgqudHsp+hd82UVkvgnlqZjzz2vyrYfz7bkPtXaGb9H4 Rfo7mQsEQavEBdWWjbga6eMnDqtu+FC+qeTGYebToxEyp2lKDSoAsvt8w82tIlP/EbmRbDVn 7bhjBlfRcFjVYw8uVDPptT0TV47vpoCVkTwcyb6OltJrvg/QzV9f07DJswuda1JH3/qvYu0p vjPnYvCq4NsqY2XSdAJ02HrdYPFtNyPEntu1n1KK+gJrstjtw7KsZ4ygXYrsm/oCBiVW/OgU g/XIlGErkrxe4vQvJyVwg6YH653YTX5hLLUEL1NS4TCo47RP+wi6y+TnuAL36UtK/uFyEuPy wwrDVcC4cIFhYSfsO0BumEI65yu7a8aHbGfq2lW251UcoU48Z27ZUUZd2Dr6O/n8poQHbaTd 6bJJSjzGGHZVbRP9UQ3lkmkmc0+XCHmj5WhwNNYjgbbmML7y0fsJT5RgvefAIFfHBg7fTY/i kBEimoUsTEQz+N4hbKwo1hULfVxDJStE4sbPhjbsPCrlXf6W9CxSyQ0qmZ2bXsLQYRj2xqd1 bpA+1o1j2N4/au1R/uSiUFjewJdT/LX1EklKDcQwpk06Af/N7VZtSfEJeRV04unbsKVXWZAk uAJyDDKN99ziC0Wz5kcPyVD1HNf8bgaqGDzrv3TfYjwqayRFcMf7xJaL9xXedMcAEQEAAcLB XwQYAQgACQUCUuE2fwIbDAAKCRBlw/kGpdefoG4XEACD1Qf/er8EA7g23HMxYWd3FXHThrVQ HgiGdk5Yh632vjOm9L4sd/GCEACVQKjsu98e8o3ysitFlznEns5EAAXEbITrgKWXDDUWGYxd pnjj2u+GkVdsOAGk0kxczX6s+VRBhpbBI2PWnOsRJgU2n10PZ3mZD4Xu9kU2IXYmuW+e5KCA vTArRUdCrAtIa1k01sPipPPw6dfxx2e5asy21YOytzxuWFfJTGnVxZZSCyLUO83sh6OZhJkk b9rxL9wPmpN/t2IPaEKoAc0FTQZS36wAMOXkBh24PQ9gaLJvfPKpNzGD8XWR5HHF0NLIJhgg 4ZlEXQ2fVp3XrtocHqhu4UZR4koCijgB8sB7Tb0GCpwK+C4UePdFLfhKyRdSXuvY3AHJd4CP 4JzW0Bzq/WXY3XMOzUTYApGQpnUpdOmuQSfpV9MQO+/jo7r6yPbxT7CwRS5dcQPzUiuHLK9i nvjREdh84qycnx0/6dDroYhp0DFv4udxuAvt1h4wGwTPRQZerSm4xaYegEFusyhbZrI0U9tJ B8WrhBLXDiYlyJT6zOV2yZFuW47VrLsjYnHwn27hmxTC/7tvG3euCklmkn9Sl9IAKFu29RSo d5bD8kMSCYsTqtTfT6W4A3qHGvIDta3ptLYpIAOD2sY3GYq2nf3Bbzx81wZK14JdDDHUX2Rs 6+ahAA== In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 27/08/2024 2:25 pm, Andrew Cooper wrote: > On 27/08/2024 2:00 pm, Jan Beulich wrote: >> On 27.08.2024 13:50, Andrew Cooper wrote: >>> On 26/08/2024 12:55 pm, Jan Beulich wrote: >>>> On 23.08.2024 01:06, Andrew Cooper wrote: >>> Again, this is modelled after f[fl]s64() which have the same >>> expectations about the BITS_PER_LONG != 64 case. >> Both of them are fine afaict. fls64() has an explicit intermediate >> variable of type uint32_t, and ffs64() has a (uint32_t)x as part >> of the conditional expression achieving the intended effect. >> >> Anyway, why not use hweight32() instead of hweightl() here? That'll >> make things very explicit. > hweight32() doesn't exist until the next patch in the series. > > Although looking at the end result, I can't figure out why I thought it > was necessary to transform hweight64 first. > > I'll swap this patch and the next one, and then use hweight32(). I've found out why. The hweight32() patch is the one that deletes generic_hweight32(), but generic_hweight64() uses it. I can work around this, but it means keeping generic_hweight32() around and deleting it in the hweight64() patch. ~Andrew