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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0C729C433F5 for ; Tue, 22 Feb 2022 16:54:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234384AbiBVQy3 (ORCPT ); Tue, 22 Feb 2022 11:54:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34154 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232223AbiBVQy3 (ORCPT ); Tue, 22 Feb 2022 11:54:29 -0500 X-Greylist: delayed 485 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Tue, 22 Feb 2022 08:54:03 PST Received: from relay4.hostedemail.com (relay4.hostedemail.com [64.99.140.37]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D3A565370D for ; Tue, 22 Feb 2022 08:54:03 -0800 (PST) Received: from omf18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 784C8A5A; Tue, 22 Feb 2022 16:45:56 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: joe@perches.com) by omf18.hostedemail.com (Postfix) with ESMTPA id 396B643; Tue, 22 Feb 2022 16:45:34 +0000 (UTC) Message-ID: <66a0c8210cf9e7dfcc3fa2d247de1eebd5a8acb7.camel@perches.com> Subject: Re: [PATCHv3 04/10] linux/kernel: introduce lower_48_bits macro From: Joe Perches To: Keith Busch , linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, linux-crypto@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org Cc: axboe@kernel.dk, hch@lst.de, martin.petersen@oracle.com, colyli@suse.de, Bart Van Assche Date: Tue, 22 Feb 2022 08:45:53 -0800 In-Reply-To: <20220222163144.1782447-5-kbusch@kernel.org> References: <20220222163144.1782447-1-kbusch@kernel.org> <20220222163144.1782447-5-kbusch@kernel.org> Content-Type: text/plain; charset="ISO-8859-1" User-Agent: Evolution 3.40.4-1ubuntu2 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspamout08 X-Rspamd-Queue-Id: 396B643 X-Stat-Signature: yzf67mxeguumtukwkfw7sqsufuzga6du X-Session-Marker: 6A6F6540706572636865732E636F6D X-Session-ID: U2FsdGVkX1+NisYWVxViQyJRvI3jjilg5uVaEbHyZ28= X-HE-Tag: 1645548334-553202 Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org On Tue, 2022-02-22 at 08:31 -0800, Keith Busch wrote: > Recent data integrity field enhancements allow 48-bit reference tags. > Introduce a helper macro since this will be a repeated operation. [] > diff --git a/include/linux/kernel.h b/include/linux/kernel.h [] > @@ -63,6 +63,12 @@ > } \ > ) > > +/** > + * lower_48_bits - return bits 0-47 of a number > + * @n: the number we're accessing > + */ > +#define lower_48_bits(n) ((u64)((n) & 0xffffffffffffull)) why not make this a static inline function? And visually, it's difficult to quickly count a repeated character to 12. Perhaps: static inline u64 lower_48_bits(u64 val) { return val & GENMASK_ULL(47, 0); }