From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wj0-f198.google.com (mail-wj0-f198.google.com [209.85.210.198]) by kanga.kvack.org (Postfix) with ESMTP id CAD356B0038 for ; Fri, 2 Dec 2016 11:44:30 -0500 (EST) Received: by mail-wj0-f198.google.com with SMTP id xy5so46153680wjc.0 for ; Fri, 02 Dec 2016 08:44:30 -0800 (PST) Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com. [148.163.158.5]) by mx.google.com with ESMTPS id n128si3750715wmf.141.2016.12.02.08.44.29 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 02 Dec 2016 08:44:29 -0800 (PST) Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id uB2GiPbN060479 for ; Fri, 2 Dec 2016 11:44:28 -0500 Received: from e37.co.us.ibm.com (e37.co.us.ibm.com [32.97.110.158]) by mx0b-001b2d01.pphosted.com with ESMTP id 2739nntvfj-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Fri, 02 Dec 2016 11:44:26 -0500 Received: from localhost by e37.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 2 Dec 2016 09:44:08 -0700 Date: Fri, 2 Dec 2016 08:44:08 -0800 From: "Paul E. McKenney" Subject: Re: INFO: rcu_sched detected stalls on CPUs/tasks with `kswapd` and `mem_cgroup_shrink_node` Reply-To: paulmck@linux.vnet.ibm.com References: <3a4242cb-0198-0a3b-97ae-536fb5ff83ec@kernelpanic.ru> <20161128143435.GC3924@linux.vnet.ibm.com> <20161128150509.GG3924@linux.vnet.ibm.com> <66fd50e1-a922-846a-f427-7654795bd4b5@kernelpanic.ru> <20161130174802.GM18432@dhcp22.suse.cz> <20161130182552.GN18432@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Message-Id: <20161202164408.GM3924@linux.vnet.ibm.com> Sender: owner-linux-mm@kvack.org List-ID: To: Boris Zhmurov Cc: Michal Hocko , Paul Menzel , Donald Buczek , linux-mm@kvack.org, linux-kernel@vger.kernel.org On Fri, Dec 02, 2016 at 07:39:24PM +0300, Boris Zhmurov wrote: > Paul E. McKenney Thu Dec 01 2016 - 14:39:21 EST: > > >> Well, I can confirm, that replacing cond_resched_rcu_qs in > >> shrink_node_memcg by cond_resched also makes dmesg clean from RCU > >> CPU stall warnings. > >> > >> I've attached patch (just modification of Paul's patch), that > >> fixes RCU stall messages in situations, when all memory is used by > >> couchbase/memcached + fs cache and linux starts to use swap. > > > Nice! Just to double-check, could you please also test your patch > > above with these two commits from -rcu? > > > > d2db185bfee8 ("rcu: Remove short-term CPU kicking") f8f127e738e3 > > ("rcu: Add long-term CPU kicking") > > > > Thanx, Paul > > > Looks like patches d2db185bfee8 and f8f127e738e3 change nothing. > > With cond_resched() in shrink_node_memcg and these two patches dmesg is > clean. No any RCU CPU stall messages. Very good! I have these two patches queued for 4.11. And thank you again for all the testing!!! Thanx, Paul -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org