From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=FROM_EXCESS_BASE64, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C239BC4360C for ; Wed, 25 Sep 2019 15:51:42 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9ABD921D7B for ; Wed, 25 Sep 2019 15:51:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9ABD921D7B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:54004 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iD9Zs-0007o6-Sh for qemu-devel@archiver.kernel.org; Wed, 25 Sep 2019 11:51:40 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:36955) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iD9Y2-0006Hm-5m for qemu-devel@nongnu.org; Wed, 25 Sep 2019 11:49:51 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iD9Xz-00011c-Br for qemu-devel@nongnu.org; Wed, 25 Sep 2019 11:49:44 -0400 Received: from mx1.redhat.com ([209.132.183.28]:56250) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iD9Xz-00010z-5P for qemu-devel@nongnu.org; Wed, 25 Sep 2019 11:49:43 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 771169D1D1 for ; Wed, 25 Sep 2019 15:49:41 +0000 (UTC) Received: from redhat.com (unknown [10.42.17.64]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 82FEF600C8; Wed, 25 Sep 2019 15:49:40 +0000 (UTC) Date: Wed, 25 Sep 2019 16:49:38 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: "Dr. David Alan Gilbert" Subject: Re: [Qemu-devel] [PATCH v3 0/5] Automatic RCU read unlock Message-ID: <20190925154938.GC2942@redhat.com> References: <20190913102538.24167-1-dgilbert@redhat.com> <20190925131324.GG21544@work-vm> <20190925152858.GE2876@work-vm> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20190925152858.GE2876@work-vm> User-Agent: Mutt/1.12.1 (2019-06-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Wed, 25 Sep 2019 15:49:41 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Cc: Paolo Bonzini , qemu-devel@nongnu.org, ehabkost@redhat.com, quintela@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Wed, Sep 25, 2019 at 04:28:58PM +0100, Dr. David Alan Gilbert wrote: > * Paolo Bonzini (pbonzini@redhat.com) wrote: > > On 25/09/19 15:13, Dr. David Alan Gilbert wrote: > > > * Dr. David Alan Gilbert (git) (dgilbert@redhat.com) wrote: > > >> From: "Dr. David Alan Gilbert" > > >> > > >> This patch uses glib's g_auto mechanism to automatically free > > >> rcu_read_lock's at the end of the block. Given that humans > > >> have a habit of forgetting an error path somewhere it's > > >> best to leave it to the compiler. > > > > > > I've had to unqueue this - clang doesn't like the apparently unused > > > auto variable; we need to find a way to make that happy. > > > > __attribute__((unused))? > > I worry that if I do that, then it'll optimise it out. Can you just insert a dummy use of the variable. eg libvirt does this by just taking the address of the unused variable and casting the result to void. Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|