From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 51700 invoked by alias); 19 Apr 2017 18:09:24 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Received: (qmail 51674 invoked by uid 89); 19 Apr 2017 18:09:23 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.9 required=5.0 tests=BAYES_00,RP_MATCHES_RCVD,SPF_HELO_PASS autolearn=ham version=3.3.2 spammy= X-HELO: mx1.redhat.com DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com C04CF7D0E2 Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=fweimer@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com C04CF7D0E2 Subject: Re: [PATCH 1/2] nptl: Remove __ASSUME_SET_ROBUST_LIST To: Adhemerval Zanella Cc: GNU C Library References: <1492550000-31374-1-git-send-email-adhemerval.zanella@linaro.org> <35b8a72e-dfce-6cd1-0998-a3866239da30@redhat.com> <85636314-6928-361f-234b-badec623b5a5@linaro.org> From: Florian Weimer Message-ID: Date: Wed, 19 Apr 2017 18:09:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit X-SW-Source: 2017-04/txt/msg00387.txt.bz2 On 04/19/2017 07:38 PM, Adhemerval Zanella wrote: > On Wed, Apr 19, 2017 at 12:28 PM, Florian Weimer wrote: >> On 04/19/2017 04:17 PM, Adhemerval Zanella wrote: >>> >>> The problem is kernel supports for some architecture depends of kernel >>> config >>> and the underlying hardware revision/model. >> >> >> I understand that. But I have seen a lot of use of robust mutexes lately, >> and I'm sure these developers aren't aware that the mutexes aren't portable >> across GNU/Linux (the Linux architecture subset supported by glibc). >> >> I expect it's like the missing accept4 system call—you need to provide the >> set_robust_list system call in the kernel if you want to a working, modern >> system. > > But my point is with current minimum supported kernel version for some > architectures > we can't simple assume set_robust_list support and even bumping minimum kernel > version for some architectures also do not solve the issue (on mips > for instance). Hmm, maybe you are right, and we have to keep things this way for now. But I don't like that your patch reintroduces the conditional code. You could use #define __set_robust_list_avail 1 for the __ASSUME_SET_ROBUST_LIST case to reduce clutter, and let GCC do the rest. Thanks, Florian