From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alan Jenkins Subject: Re: s2disk hang update Date: Wed, 17 Feb 2010 11:27:30 +0000 Message-ID: <9b2b86521002170327m1f08ff73ncca9e5eff77b1966__47863.4226987653$1266406247$gmane$org@mail.gmail.com> References: <9b2b86521001020703v23152d0cy3ba2c08df88c0a79@mail.gmail.com> <9b2b86521002160309g26d60bd2t4c19bd2294b76c28@mail.gmail.com> <9b2b86521002160712r39ecb2b1q5e01389e9209e17b@mail.gmail.com> <201002162216.30192.rjw@sisk.pl> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <201002162216.30192.rjw@sisk.pl> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: "Rafael J. Wysocki" Cc: Mel Gorman , linux-kernel , hugh.dickins@tiscali.co.uk, pm list , Kernel Testers List List-Id: linux-pm@vger.kernel.org On 2/16/10, Rafael J. Wysocki wrote: > On Tuesday 16 February 2010, Alan Jenkins wrote: >> On 2/16/10, Alan Jenkins wrote: >> > On 2/15/10, Rafael J. Wysocki wrote: >> >> On Tuesday 09 February 2010, Alan Jenkins wrote: >> >>> Perhaps I spoke too soon. I see the same hang if I run too many >> >>> applications. The first hibernation fails with "not enough swap" as >> >>> expected, but the second or third attempt hangs (with the same >> >>> backtrace >> >>> as before). >> >>> >> >>> The patch definitely helps though. Without the patch, I see a hang >> >>> the >> >>> first time I try to hibernate with too many applications running. >> >> >> >> Well, I have an idea. >> >> >> >> Can you try to apply the appended patch in addition and see if that >> >> helps? >> >> >> >> Rafael >> > >> > It doesn't seem to help. >> >> To be clear: It doesn't stop the hang when I hibernate with too many >> applications. >> >> It does stop the same hang in a different case though. >> >> 1. boot with init=/bin/bash >> 2. run s2disk >> 3. cancel the s2disk >> 4. repeat steps 2&3 >> >> With the patch, I can run 10s of iterations, with no hang. >> Without the patch, it soon hangs, (in disable_nonboot_cpus(), as always). >> >> That's what happens on 2.6.33-rc7. On 2.6.30, there is no problem. >> On 2.6.31 and 2.6.32 I don't get a hang, but dmesg shows an allocation >> failure after a couple of iterations ("kthreadd: page allocation >> failure. order:1, mode:0xd0"). It looks like it might be the same >> stop_machine thread allocation failure that causes the hang. > > Have you tested it alone or on top of the previous one? If you've tested it > alone, please apply the appended one in addition to it and retest. > > Rafael I did test with both patches applied together - 1. [Update] MM / PM: Force GFP_NOIO during suspend/hibernation and resume 2. "reducing the number of pages that we're going to keep preallocated by 20%" Alan