From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steven Rostedt Subject: Re: Filesystem lockup with CONFIG_PREEMPT_RT Date: Fri, 27 Jun 2014 13:54:15 -0400 Message-ID: <20140627135415.7246e87e@gandalf.local.home> References: <1403873856.5827.56.camel@marge.simpson.net> <20140627100157.6b0143a5@gandalf.local.home> <1403890493.5830.33.camel@marge.simpson.net> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Austin Schuh , Thomas Gleixner , Richard Weinberger , LKML , rt-users To: Mike Galbraith Return-path: In-Reply-To: <1403890493.5830.33.camel@marge.simpson.net> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-rt-users.vger.kernel.org On Fri, 27 Jun 2014 19:34:53 +0200 Mike Galbraith wrote: > On Fri, 2014-06-27 at 10:01 -0400, Steven Rostedt wrote: > > > This seems like a lot of hacks. > > It is exactly that, lacking proper pooper-scooper, show rt kernel how to > not step in it. > > > I'm wondering if it would work if we > > just have the rt_spin_lock_slowlock not call schedule(), but call > > __schedule() directly. I mean it would keep with the mainline paradigm > > as spinlocks don't sleep there, and one going to sleep in the -rt > > kernel is similar to it being preempted by a very long NMI. > > Problem being that we do sleep there, do need wakeup. I have a hack > that turns them back into spinning locks, but it.. works too :) Why do we need the wakeup? the owner of the lock should wake it up shouldn't it? -- Steve