From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f69.google.com (mail-wm0-f69.google.com [74.125.82.69]) by kanga.kvack.org (Postfix) with ESMTP id CD5536B0253 for ; Thu, 14 Dec 2017 15:40:42 -0500 (EST) Received: by mail-wm0-f69.google.com with SMTP id n126so3018340wma.7 for ; Thu, 14 Dec 2017 12:40:42 -0800 (PST) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org. [140.211.169.12]) by mx.google.com with ESMTPS id z63si3613300wmz.126.2017.12.14.12.40.38 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 14 Dec 2017 12:40:38 -0800 (PST) Date: Thu, 14 Dec 2017 12:40:35 -0800 From: Andrew Morton Subject: Re: [PATCH V3] mm/mprotect: Add a cond_resched() inside change_pmd_range() Message-Id: <20171214124035.e77706f0a314f2082a2d1b7c@linux-foundation.org> In-Reply-To: <20171214140551.5794-1-khandual@linux.vnet.ibm.com> References: <20171214140551.5794-1-khandual@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Anshuman Khandual Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, mhocko@suse.com On Thu, 14 Dec 2017 19:35:51 +0530 Anshuman Khandual wrote: > While testing on a large CPU system, detected the following RCU > stall many times over the span of the workload. This problem > is solved by adding a cond_resched() in the change_pmd_range() > function. > > [ 850.962530] INFO: rcu_sched detected stalls on CPUs/tasks: That's a bit rude. I think I'll add a cc:stable to this one. -- 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