From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755656Ab3IYNsN (ORCPT ); Wed, 25 Sep 2013 09:48:13 -0400 Received: from e34.co.us.ibm.com ([32.97.110.152]:59965 "EHLO e34.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755415Ab3IYNsM (ORCPT ); Wed, 25 Sep 2013 09:48:12 -0400 Date: Wed, 25 Sep 2013 06:48:04 -0700 From: "Paul E. McKenney" To: Andrew Morton Cc: linux-kernel@vger.kernel.org, mingo@kernel.org, laijs@cn.fujitsu.com, dipankar@in.ibm.com, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, niv@us.ibm.com, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, darren@dvhart.com, fweisbec@gmail.com, sbw@mit.edu, KOSAKI Motohiro , Michel Lespinasse , Linus Torvalds Subject: Re: [PATCH tip/core/rcu 01/11] mm: Place preemption point in do_mlockall() loop Message-ID: <20130925134803.GQ9093@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <20130925012750.GA30601@linux.vnet.ibm.com> <1380072561-31134-1-git-send-email-paulmck@linux.vnet.ibm.com> <20130924211047.57f9d9c8.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130924211047.57f9d9c8.akpm@linux-foundation.org> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13092513-1542-0000-0000-000001BC58B9 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 24, 2013 at 09:10:47PM -0700, Andrew Morton wrote: > On Tue, 24 Sep 2013 18:29:11 -0700 "Paul E. McKenney" wrote: > > > --- a/mm/mlock.c > > +++ b/mm/mlock.c > > @@ -736,6 +736,7 @@ static int do_mlockall(int flags) > > > > /* Ignore errors */ > > mlock_fixup(vma, &prev, vma->vm_start, vma->vm_end, newflags); > > + cond_resched(); > > } > > out: > > return 0; > > Might need one in munlock_vma_pages_range() as well - it's a matter of > finding the right test case. This will be neverending :( Indeed... I suspect that Trinity running on big-memory systems will eventually find most of them via RCU CPU stall warnings, but as you say... Would you like the corresponding change to munlock_vma_pages_range() beforehand? Thanx, Paul