From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 108949 invoked by alias); 31 May 2018 14:55:57 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 108938 invoked by uid 89); 31 May 2018 14:55:56 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.9 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS autolearn=ham version=3.3.2 spammy=rationale, letter X-HELO: mx1.redhat.com Received: from mx3-rdu2.redhat.com (HELO mx1.redhat.com) (66.187.233.73) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Thu, 31 May 2018 14:55:55 +0000 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D349E76F91; Thu, 31 May 2018 14:55:53 +0000 (UTC) Received: from [127.0.0.1] (ovpn04.gateway.prod.ext.ams2.redhat.com [10.39.146.4]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3ADD02024CA4; Thu, 31 May 2018 14:55:52 +0000 (UTC) Subject: Re: [PATCH 2/8] Function for reading the Aarch64 SVE vector length. To: Alan Hayward , gdb-patches@sourceware.org References: <20180511105256.27388-1-alan.hayward@arm.com> <20180511105256.27388-3-alan.hayward@arm.com> Cc: nd@arm.com From: Pedro Alves Message-ID: <37fab60c-b754-4a18-96b8-1a41f1cde441@redhat.com> Date: Thu, 31 May 2018 14:57:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: <20180511105256.27388-3-alan.hayward@arm.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-SW-Source: 2018-05/txt/msg00854.txt.bz2 On 05/11/2018 11:52 AM, Alan Hayward wrote: > Add a method for reading the SVE vector length using ptrace. This returns > 0 for systems without SVE support. > > Note the defines taken from Linux kernel headers in aarch64-sve-linux-ptrace.h. > See the covering email for details about this. Note that since the cover email doesn't make it to the git repo, it's better to do things the other way around, leave the details in the commit, and a summary in the cover letter. Someone looking at git log won't have a reference to the cover letter. Or, if it makes sense for readers of the code, as opposed to just a rationale for a change, put it in comments instead. (I don't know whether that's true, just stating a principle.) > > There are multiple ways of expressing the vector length. Thankfully these are > all wll defined. I've added convertors for going from one to the other. "well", "converters". > +struct user_sve_header { > + __u32 size; /* total meaningful regset content in bytes */ > + __u32 max_size; /* maxmium possible size for this thread */ "maximum" Thanks, Pedro Alves