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 27E26ECAAA1 for ; Sun, 30 Oct 2022 21:52:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229695AbiJ3Vwh (ORCPT ); Sun, 30 Oct 2022 17:52:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49638 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229520AbiJ3Vwb (ORCPT ); Sun, 30 Oct 2022 17:52:31 -0400 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 78AA8AE60 for ; Sun, 30 Oct 2022 14:52:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1667166750; x=1698702750; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=yKV0kn7+sNjHxDv1drM+NAfrxBAs+SlnJFwDA8xfygk=; b=ZPajshVS5uriUAaYlgXqQEFGBFNhgjm60vBkwtofzOfQoA7SEkny9LhK 6RDSmsfwgwsUvkAEDEJJ15UtPKEh/xdHLrJ1BC+dUT2erYtRDb4PKBEoI VR6wo70QdJDvel6fpY4igZ5x7ndU7dXMO9z+kMaXRBzhJvHs7/3ILpNbt G8MgBdLRxrWOV0V8S2k6dbxswczrVrcd6oL01B+CPXxpMniLA3zLqaq1u S88IKUoC6UFEp5nQwTCC8UoOVUmZBnkDyQ8GMyy4hhmzlh9cwEi7ADsGT laxiNMwU2D1UrZ3WOjqieMLyyzHKdgwNpRWK3sFo9/Y2BQ12nPOEqw0Cy g==; X-IronPort-AV: E=McAfee;i="6500,9779,10516"; a="309866797" X-IronPort-AV: E=Sophos;i="5.95,226,1661842800"; d="scan'208";a="309866797" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Oct 2022 14:52:30 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10516"; a="584466440" X-IronPort-AV: E=Sophos;i="5.95,226,1661842800"; d="scan'208";a="584466440" Received: from smile.fi.intel.com ([10.237.72.54]) by orsmga003.jf.intel.com with ESMTP; 30 Oct 2022 14:52:28 -0700 Received: from andy by smile.fi.intel.com with local (Exim 4.96) (envelope-from ) id 1opGEF-004pPT-0T; Sun, 30 Oct 2022 23:52:27 +0200 Date: Sun, 30 Oct 2022 23:52:26 +0200 From: Andy Shevchenko To: Alexey Dobriyan Cc: mingo@kernel.org, akpm@linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [rft, PATCH v1 4/4] kernel.h: Split out ARRAY_SZIE() Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Oct 29, 2022 at 01:05:43PM +0300, Alexey Dobriyan wrote: > On Tue, Oct 25, 2022 at 11:20:10AM +0300, Andy Shevchenko wrote: > > On Mon, Oct 24, 2022 at 09:14:29PM +0300, Alexey Dobriyan wrote: > > > On Mon, Oct 24, 2022 at 07:05:18PM +0300, Andy Shevchenko wrote: > > > > On Mon, Oct 24, 2022 at 06:44:50PM +0300, Alexey Dobriyan wrote: > > > > > > include/linux/array_size.h | 13 +++++++++++++ > > > > > > > > > > All of this is pessimisation unless you're removing > > > > > > > > > > +#include > > > > > > > > > > from kernel.h which you aren't doing. > > > > > > > > > > container_of.h is just as silly. > > > > > > > > > > kernel.h might need _some_ cleanup (like panic and tainted stuff) which > > > > > is rarely used but ARRAY_SIZE()? > > > > > > > > Are you suggesting to slow down compilation with inclusion of tons of unneeded > > > > stuff in the zillions of drivers? > > > > > > > > Or you are talking that we need to abandon most of the headers and combine > > > > everything into kernel.h? I think this is what is silly. > > > > > > It hard to escape kernel.h so you will be including it anyway. > > > > It's very important to not include it in the headers. > > > > And this split helps to it a lot. We have container_of() or array_size() used > > in macros and/or inliners that are usually appears in the headers. And if you > > know what dependency hell means, the kernel.h brings to it a huge mess. > > > > So, try to be constructive, okay? > > > > > Unless you delete, say, kstrtox.h from kernel.h, it is pointless busywork. > > I'm very constructive. > > Parsing 1 define is faster than opening/reading/closing a file to parse > 1 define (it's 2 defines because of header guard). > > Therefore extracting 1 macro into separate file without obvious future > growth is a pessimisation. You are looking at it at the wrong side. The opening one file inside a single file maybe a way to slow down the compilation, but cleaning up the _headers_ from kernel.h and similar mess is a definite win. Ingo, for example, unwounded the thread coil for the scheduler code with a significant win. And his work exactly shows why it's right way to go. > And if you delete #include from kernel.h and fix all > compile failures (which you aren't doing apparently) backporters will > hate you for life. It would need some time to have kernel.h to be hanging as is before we can start cleaning the mess our of it. I prefer to kill the whole header or leave there only really _kernel_ parts. > I've tried to delete kstrtox.h, and even allnoconfig had dozens of > failures. So, help us and fix them! -- With Best Regards, Andy Shevchenko