Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754772AbdIFRHc (ORCPT ); Wed, 6 Sep 2017 13:07:32 -0400 Received: from sender-pp-091.zoho.com ([135.84.80.236]:25061 "EHLO sender-pp-091.zoho.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754275AbdIFRHb (ORCPT ); Wed, 6 Sep 2017 13:07:31 -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=qufJ3mZp20bBwpwsFojZlxhwS7z2pcdQF3GtK66ROP5LVxUrV9dpDnPZyfkpTDs8hWb+CPuSZW2n 5excgy+NbQSjh0QmeR7PKtXwH2QQq07Y0NmvHO/uV2zqJjrINa30 Subject: Re: [PATCH 1/1] workqueue: use type int instead of bool to index array To: Tejun Heo References: <59AF6CB6.4090609@zoho.com> <20170906143320.GK1774378@devbig577.frc2.facebook.com> <20170906164015.GQ1774378@devbig577.frc2.facebook.com> Cc: zijun_hu@htc.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton , jiangshanlai@gmail.com From: zijun_hu Message-ID: <58cb4eab-8334-a884-efa3-8752c34112e5@zoho.com> Date: Thu, 7 Sep 2017 01:07:23 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <20170906164015.GQ1774378@devbig577.frc2.facebook.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-ZohoMailClient: External Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1496 Lines: 33 On 2017/9/7 0:40, Tejun Heo wrote: > On Thu, Sep 07, 2017 at 12:04:59AM +0800, zijun_hu wrote: >> On 2017/9/6 22:33, Tejun Heo wrote: >>> Hello, >>> >>> On Wed, Sep 06, 2017 at 11:34:14AM +0800, zijun_hu wrote: >>>> From: zijun_hu >>>> >>>> type bool is used to index three arrays in alloc_and_link_pwqs() >>>> it doesn't look like conventional. >>>> >>>> it is fixed by using type int to index the relevant arrays. >>> >>> bool is a uint type which can be either 0 or 1. I don't see what the >>> benefit of this patch is.q >>> >> bool is NOT a uint type now, it is a new type introduced by gcc, it is >> rather different with "typedef int bool" historically > > http://www.open-std.org/jtc1/sc22/wg14/www/docs/n815.htm > > Because C has existed for so long without a Boolean type, however, the > new standard must coexist with the old remedies. Therefore, the type > name is taken from the reserved identifier space. To maintain > orthogonal promotion rules, the Boolean type is defined as an unsigned > integer type capable of representing the values 0 and 1. The more > conventional names for the type and its values are then made available > only with the inclusion of the header. In addition, the > header defines a feature test macro to aid in integrating new code > with old code that defines its own Boolean type. > in this case, i think type int is more suitable than bool in aspects of extendibility, program custom and consistency.