From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 116131 invoked by alias); 20 Apr 2017 12:51:00 -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 114949 invoked by uid 89); 20 Apr 2017 12:51:00 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.0 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_NONE,RCVD_IN_SORBS_SPAM,SPF_PASS autolearn=no version=3.3.2 spammy= X-HELO: mail-qk0-f178.google.com X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:cc:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding; bh=Xs6jtwYbULoNzkurTcWPK/gooCjRxJ3BWXDtihypIFw=; b=WrwttT2tbv6VIRZaWPU6Sf+osPxMi6FZpvfeE/Lg4XgWJdOCYbiN/qnFh8QVec7e01 3Abl0XIFM7vrSHSsIdbvY3e7lQlv3qieb2/BY5lHJ4RxoOw5PSBX0W7K1emGQMtDE7LY t2Nb7amUEHZrE8NWALN2TSeSQ3zVTwW7ge/bsqVnyqVCqYpo7GnDL0akMYIlXN2B8Mm1 xeR0XfGlCVRtjrWBQGW7xaTUQzxDNku0cbK7/JU9CG5JA68LtOHSSDeatYGwdc3mjXMv B/qch6araiqicaza6DBgPbR0Mca57iC4rIpYcPSak9snhcXzRgxLnzrFMVFpWHIkNxXc kcNA== X-Gm-Message-State: AN3rC/4JS6KPU+YTbdIBJ+ayBn4r0BwAQvA/fZcf5fjySiHgWeHaen+A ogwdEzBYZyKVVvKL X-Received: by 10.55.79.130 with SMTP id d124mr8230633qkb.92.1492692658392; Thu, 20 Apr 2017 05:50:58 -0700 (PDT) Subject: Re: [PATCH 1/2] nptl: Remove __ASSUME_SET_ROBUST_LIST To: Florian Weimer 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> Cc: GNU C Library From: Adhemerval Zanella Message-ID: <8469b941-ac1f-1cda-ac15-1f8747ea69a2@linaro.org> Date: Thu, 20 Apr 2017 12:51:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-SW-Source: 2017-04/txt/msg00411.txt.bz2 On 19/04/2017 15:09, Florian Weimer wrote: > 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. Rechecking what you meant, I am not following you here: the idea is to have __set_robust_list_avail being a runtime variable and get rid of the _ASSUME define. How using a define would help in this way?