Path: csiph.com!1.us.feeder.erje.net!feeder.erje.net!1.eu.feeder.erje.net!news2.arglkargh.de!news.mixmin.net!aioe.org!bofh.it!news.nic.it!robomod From: Sebastian Andrzej Siewior Newsgroups: linux.kernel Subject: Re: [PATCH RT] Align rt_mutex inlining with upstream behavior Date: Fri, 10 Feb 2017 19:30:01 +0100 Message-ID: References: X-Original-To: Andy Ritger MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8BIT User-Agent: NeoMutt/20170113 (1.7.2) Sender: robomod@news.nic.it List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Approved: robomod@news.nic.it Lines: 27 Organization: linux.* mail to news gateway X-Original-Cc: Alex Goins , Thomas Gleixner , LKML , linux-rt-users@vger.kernel.org, Ingo Molnar X-Original-Date: Fri, 10 Feb 2017 19:28:07 +0100 X-Original-Message-ID: <20170210182807.6gzs3xn3ga727xsb@linutronix.de> X-Original-References: <1485312350-1265-1-git-send-email-agoins@nvidia.com> <20170126170109.6zhoohgodtvxot54@linutronix.de> <20170130173534.GA24966@prokofiev.nvidia.com> <20170203155434.utptndmoskcyimn7@linutronix.de> <20170203164924.GB19814@prokofiev.nvidia.com> <20170210175049.3cvrk5ki7c6uiblg@linutronix.de> <20170210180929.GC9583@prokofiev.nvidia.com> X-Original-Sender: linux-kernel-owner@vger.kernel.org Xref: csiph.com linux.kernel:1578681 On 2017-02-10 10:09:29 [-0800], Andy Ritger wrote: > Is the > > WARN_ON(rt_mutex_is_locked(lock)); > > in rt_mutex_destroy() valuable in non-CONFIG_DEBUG_MUTEXES kernels, > such that it would be better to always call it, and not noop away mutex_destroy() > non-CONFIG_DEBUG_MUTEXES kernels? I thought that was your objection to > Alex's original patch. It kind of was… So first I removed the GPL symbol. Then I wasn't too happy about it especially since it was not introduced as part of RT. So I reverted that changed and aligned with mainline behaviour (the mutex_rt.h hunk). But then I noticed that with CONFIG_DEBUG_MUTEXES=n and CONFIG_DEBUG_RT_MUTEXES=y we still have a regression compared to !RT and this was the initial motivation to fix things. Then I got curious why mutex_lock() (which is essential rt_mutex_lock()) works and noticed the wrapper around it. And while looking at it I decided to go back to strip the GPL part from export symbol instead of adding a wrapper. And here I am. Then I was looking at the patch and decided to align with mainline (and keep that one hunk) in case Ingo ask for his GPL symbol. > Thanks, > - Andy Sebastian