From owner-svn-src-head@freebsd.org Thu Mar 3 12:27:16 2016 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id C834476AA; Thu, 3 Mar 2016 12:27:16 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from kib.kiev.ua (kib.kiev.ua [IPv6:2001:470:d5e7:1::1]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4993D6B7; Thu, 3 Mar 2016 12:27:16 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from tom.home (kostik@localhost [127.0.0.1]) by kib.kiev.ua (8.15.2/8.15.2) with ESMTPS id u23CRBNE000764 (version=TLSv1 cipher=DHE-RSA-CAMELLIA256-SHA bits=256 verify=NO); Thu, 3 Mar 2016 14:27:11 +0200 (EET) (envelope-from kostikbel@gmail.com) DKIM-Filter: OpenDKIM Filter v2.10.3 kib.kiev.ua u23CRBNE000764 Received: (from kostik@localhost) by tom.home (8.15.2/8.15.2/Submit) id u23CRBlh000763; Thu, 3 Mar 2016 14:27:11 +0200 (EET) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com using -f Date: Thu, 3 Mar 2016 14:27:11 +0200 From: Konstantin Belousov To: Hans Petter Selasky Cc: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r296320 - in head/sys: kern sys Message-ID: <20160303122711.GR67250@kib.kiev.ua> References: <201603021846.u22IkHWM010861@repo.freebsd.org> <56D81918.6020403@selasky.org> <20160303112716.GO67250@kib.kiev.ua> <56D821A7.2020105@selasky.org> <20160303115823.GQ67250@kib.kiev.ua> <56D82A15.3050804@selasky.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <56D82A15.3050804@selasky.org> User-Agent: Mutt/1.5.24 (2015-08-30) X-Spam-Status: No, score=-2.0 required=5.0 tests=ALL_TRUSTED,BAYES_00, DKIM_ADSP_CUSTOM_MED,FREEMAIL_FROM,NML_ADSP_CUSTOM_MED autolearn=no autolearn_force=no version=3.4.1 X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on tom.home X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 03 Mar 2016 12:27:16 -0000 On Thu, Mar 03, 2016 at 01:12:05PM +0100, Hans Petter Selasky wrote: > On 03/03/16 12:58, Konstantin Belousov wrote: > >> > > >> >Yes, your change is compatible if you compile the code, but not binary > >> >compatible. See the following macros, and how they use _callout_stop_safe(): > > My change is binary compatible. > > > >> > > >> >#define callout_stop(c) _callout_stop_safe(c, 0, NULL) > >> >#define callout_async_drain(c, d) \ > >> > _callout_stop_safe(c, 0, d) > >> > > >> >Because callout_stop(c) is a macro, you've now change the API for > >> >callout_stop() aswell. This is what I think will break binary > >> >compatibility in 10.x. > > How my commit changes anything for either callout_stop(), or for > > callout_async_drain(), or for callout_drain() ? > > > > Hi, > > It looked like you added another argument to _callout_stop_safe(). After > a closer look I see the patch is binary compatible. Right, and CS_DRAIN value was selected so that callout_drain() arguments to _callout_stop_safe() would be same with or without the change. The only case where the issue could exists, is for some code which called _callout_stop_safe() directly, and passed arbitrary (not "1") non-zero value as the second argument to indicate drain. I believe there is no such code, and tend to consider it as bug, if demostrated. be not different with