From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 22 Aug 2008 10:05:45 +0900 From: KOSAKI Motohiro Subject: Re: [RFC][PATCH 1/2] Show quicklist at meminfo In-Reply-To: <2f11576a0808210036icd9b61eue58049f15381bcc8@mail.gmail.com> References: <20080820113559.f559a411.akpm@linux-foundation.org> <2f11576a0808210036icd9b61eue58049f15381bcc8@mail.gmail.com> Message-Id: <20080822100049.F562.KOSAKI.MOTOHIRO@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: KOSAKI Motohiro Cc: Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, cl@linux-foundation.org, tokunaga.keiich@jp.fujitsu.com List-ID: > > quicklist_total_size() is racy against cpu hotplug. That's OK for > > /proc/meminfo purposes (occasional transient inaccuracy?), but will it > > crash? Not in the current implementation of per_cpu() afaict, but it > > might crash if we ever teach cpu hotunplug to free up the percpu > > resources. > > First, Quicklist doesn't concern to cpu hotplug at all. > it is another quicklist problem. > > Next, I think it doesn't cause crash. but I haven't any test. > So, I'll test cpu hotplug/unplug testing today. > > I'll report result tommorow. OK. I ran cpu hotplug/unplug coutinuous workload over 12H. then, system crash doesn't happend. So, I believe my patch is cpu unplug safe. test method -------------------------------------------------------------- 1. open 7 terminal and following script run on each console. CPU=cpuXXX; while true; do echo 0 > /sys/devices/system/cpu/$CPU/online; echo 1 > /sys/devi ces/system/cpu/$CPU/online;done 2. open another console, following command run. watch -n 1 cat /proc/meminfo -- 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