From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753480AbcHQXwA (ORCPT ); Wed, 17 Aug 2016 19:52:00 -0400 Received: from sender153-mail.zoho.com ([74.201.84.153]:21631 "EHLO sender153-mail.zoho.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752797AbcHQXv7 (ORCPT ); Wed, 17 Aug 2016 19:51:59 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=zapps768; d=zoho.com; h=subject:to:references:cc:from:message-id:date:user-agent:mime-version:in-reply-to:content-type; b=IHYgTq/uAmeSt2+B/huyawg/+w4y9hbqw2uSSs6Hm+e2xDd0eY/G5D3Jh6Ajib27SBljrYlG3DzP FbVh8vXSj9TKPSj8ThB/VmifV5p5L6hWZ2GcHy+UuLf82g7L1Nxc Subject: Re: [RESEND PATCH 1/1] bitops.h: move out get_count_order[_long]() from __KERNEL__ scope To: Al Viro References: <57B2B238.3030709@zoho.com> <57B2C4CE.80303@zoho.com> <20160817172056.GE2356@ZenIV.linux.org.uk> Cc: Stephen Rothwell , Andrew Morton , "linux-kernel@vger.kernel.org" From: zijun_hu Message-ID: Date: Thu, 18 Aug 2016 07:51:19 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: <20160817172056.GE2356@ZenIV.linux.org.uk> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2016/8/18 1:20, Al Viro wrote: > On Tue, Aug 16, 2016 at 03:46:22PM +0800, zijun_hu wrote: >> From: zijun_hu >> >> move out get_count_order[_long]() definitions from scope limited >> by macro __KERNEL__ >> >> it not only make both functions available in wider region regardless >> of whether __KERNEL__ is defined but also keep original region for >> get_count_order() before the recent commit c513b4cd2fe9 >> ("mm-vmalloc-fix-align-value-calculation-error-v2-fix-fix") > > What the hell is anything without __KERNEL__ doing with linux/bitops.h in > the first place? IOW, why do we have those ifdefs at all? > __KERNEL__ is used to indicate the relevant sections within kernel headers can't be exported to or used by user space let me illuminate this patch background firstly i and Andrew develop another patch to fix a mm issue recently, that patch move get_count_order() into __KERNEL__ scope, so touch the function's scope property we don't need to touch or care the aim of this patch is undoing our unnecessary changes