Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756948AbcDGQrm (ORCPT ); Thu, 7 Apr 2016 12:47:42 -0400 Received: from www.linutronix.de ([62.245.132.108]:48752 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752235AbcDGQrk (ORCPT ); Thu, 7 Apr 2016 12:47:40 -0400 Subject: Re: [PATCH RT 4/6] rt/locking: Reenable migration accross schedule To: Mike Galbraith References: <1455318168-7125-1-git-send-email-bigeasy@linutronix.de> <1455318168-7125-4-git-send-email-bigeasy@linutronix.de> <1458463425.3908.5.camel@gmail.com> <1458814024.23732.35.camel@gmail.com> <1459405903.14336.64.camel@gmail.com> <20160401211105.GE29603@linutronix.de> <1459566735.3779.36.camel@gmail.com> Cc: Thomas Gleixner , linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org, Steven Rostedt , Peter Zijlstra From: Sebastian Andrzej Siewior Message-ID: <57068F28.8010409@linutronix.de> Date: Thu, 7 Apr 2016 18:47:36 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Icedove/38.7.0 MIME-Version: 1.0 In-Reply-To: <1459566735.3779.36.camel@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 927 Lines: 24 On 04/02/2016 05:12 AM, Mike Galbraith wrote: >> By the time I improved hotplug I played with this. I had a few ideas but >> it didn't fly in the end. Today however I ended up with this: > > Yeah, but that fails the duct tape test too. Mine is below, and is the > extra sticky variety ;-) With busted 0299 patch reverted and those two > applied, my DL980 took a beating for ~36 hours before I aborted it.. ie > hotplug road seemingly has no more -rt specific potholes. just to be clear: The patch I attached did _not_ work for you. > If that lock dies, we can unpin when entering lock slow path and pin > again post acquisition with no ABBA worries as well, and not only does > existing hotplug work heaping truckloads better, -rt can perhaps help > spot trouble as the rewrite proceeds. > > Current state is more broken than ever.. if that's possible. And the two patches you attached here did? > > -Mike Sebastian