From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f198.google.com (mail-wr0-f198.google.com [209.85.128.198]) by kanga.kvack.org (Postfix) with ESMTP id 78FE4280310 for ; Mon, 21 Aug 2017 02:47:14 -0400 (EDT) Received: by mail-wr0-f198.google.com with SMTP id q49so8583283wrb.14 for ; Sun, 20 Aug 2017 23:47:14 -0700 (PDT) Received: from mx1.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id m7si7246057wrf.12.2017.08.20.23.47.12 for (version=TLS1 cipher=AES128-SHA bits=128/128); Sun, 20 Aug 2017 23:47:13 -0700 (PDT) Date: Mon, 21 Aug 2017 08:47:09 +0200 From: Michal Hocko Subject: Re: [PATCH][RFC v4] PM / Hibernate: Feed the wathdog when creating snapshot Message-ID: <20170821064709.GE13724@dhcp22.suse.cz> References: <1503138086-19174-1-git-send-email-yu.c.chen@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1503138086-19174-1-git-send-email-yu.c.chen@intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: Chen Yu Cc: linux-mm@kvack.org, Andrew Morton , Mel Gorman , Vlastimil Babka , "Rafael J. Wysocki" , Len Brown , Dan Williams , linux-kernel@vger.kernel.org On Sat 19-08-17 18:21:26, Chen Yu wrote: > There is a problem that when counting the pages for creating > the hibernation snapshot will take significant amount of > time, especially on system with large memory. Since the counting > job is performed with irq disabled, this might lead to NMI lockup. > The following warning were found on a system with 1.5TB DRAM: > > [ 1124.758184] Freezing user space processes ... (elapsed 0.002 seconds) done. > [ 1124.768721] OOM killer disabled. > [ 1124.847009] PM: Preallocating image memory... > [ 1139.392042] NMI watchdog: Watchdog detected hard LOCKUP on cpu 27 > [ 1139.392076] CPU: 27 PID: 3128 Comm: systemd-sleep Not tainted 4.13.0-0.rc2.git0.1.fc27.x86_64 #1 > [ 1139.392077] task: ffff9f01971ac000 task.stack: ffffb1a3f325c000 > [ 1139.392083] RIP: 0010:memory_bm_find_bit+0xf4/0x100 > [ 1139.392084] RSP: 0018:ffffb1a3f325fc20 EFLAGS: 00000006 > [ 1139.392084] RAX: 0000000000000000 RBX: 0000000013b83000 RCX: ffff9fbe89caf000 > [ 1139.392085] RDX: ffffb1a3f325fc30 RSI: 0000000000003200 RDI: ffff9fbeaffffe80 > [ 1139.392085] RBP: ffffb1a3f325fc40 R08: 0000000013b80000 R09: ffff9fbe89c54878 > [ 1139.392085] R10: ffffb1a3f325fc2c R11: 0000000013b83200 R12: 0000000000000400 > [ 1139.392086] R13: fffffd552e0c0000 R14: ffff9fc1bffd31e0 R15: 0000000000000202 > [ 1139.392086] FS: 00007f3189704180(0000) GS:ffff9fbec8ec0000(0000) knlGS:0000000000000000 > [ 1139.392087] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 1139.392087] CR2: 00000085da0f7398 CR3: 000001771cf9a000 CR4: 00000000007406e0 > [ 1139.392088] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > [ 1139.392088] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > [ 1139.392088] PKRU: 55555554 > [ 1139.392089] Call Trace: > [ 1139.392092] ? memory_bm_set_bit+0x29/0x60 > [ 1139.392094] swsusp_set_page_free+0x2b/0x30 > [ 1139.392098] mark_free_pages+0x147/0x1c0 > [ 1139.392099] count_data_pages+0x41/0xa0 > [ 1139.392101] hibernate_preallocate_memory+0x80/0x450 > [ 1139.392102] hibernation_snapshot+0x58/0x410 > [ 1139.392103] hibernate+0x17c/0x310 > [ 1139.392104] state_store+0xdf/0xf0 > [ 1139.392107] kobj_attr_store+0xf/0x20 > [ 1139.392111] sysfs_kf_write+0x37/0x40 > [ 1139.392113] kernfs_fop_write+0x11c/0x1a0 > [ 1139.392117] __vfs_write+0x37/0x170 > [ 1139.392121] ? handle_mm_fault+0xd8/0x230 > [ 1139.392122] vfs_write+0xb1/0x1a0 > [ 1139.392123] SyS_write+0x55/0xc0 > [ 1139.392126] entry_SYSCALL_64_fastpath+0x1a/0xa5 > ... > [ 1144.690405] done (allocated 6590003 pages) > [ 1144.694971] PM: Allocated 26360012 kbytes in 19.89 seconds (1325.28 MB/s) > > It has taken nearly 20 seconds(2.10GHz CPU) thus the NMI lockup > was triggered. In case the timeout of the NMI watch dog has been > set to 1 second, a safe interval should be 6590003/20 = 320k pages > in theory. However there might also be some platforms running at a > lower frequency, so feed the watchdog every 100k pages. > > Reported-by: Jan Filipcewicz > Suggested-by: Michal Hocko > Cc: Andrew Morton > Cc: Michal Hocko > Cc: Mel Gorman > Cc: Vlastimil Babka > Cc: "Rafael J. Wysocki" > Cc: Len Brown > Cc: Dan Williams > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Chen Yu OK, this looks better. Feel free to add Reviewed-by: Michal Hocko > --- > mm/page_alloc.c | 14 ++++++++++++-- > 1 file changed, 12 insertions(+), 2 deletions(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 6d00f74..543726a 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -66,6 +66,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -2531,9 +2532,12 @@ void drain_all_pages(struct zone *zone) > > #ifdef CONFIG_HIBERNATION > > +/* Touch watchdog for every WD_INTERVAL_PAGE pages. */ > +#define WD_INTERVAL_PAGE (100*1024) > + > void mark_free_pages(struct zone *zone) > { > - unsigned long pfn, max_zone_pfn; > + unsigned long pfn, max_zone_pfn, page_num = 0; > unsigned long flags; > unsigned int order, t; > struct page *page; > @@ -2548,6 +2552,9 @@ void mark_free_pages(struct zone *zone) > if (pfn_valid(pfn)) { > page = pfn_to_page(pfn); > > + if (!((page_num++) % WD_INTERVAL_PAGE)) > + touch_nmi_watchdog(); > + > if (page_zone(page) != zone) > continue; > > @@ -2561,8 +2568,11 @@ void mark_free_pages(struct zone *zone) > unsigned long i; > > pfn = page_to_pfn(page); > - for (i = 0; i < (1UL << order); i++) > + for (i = 0; i < (1UL << order); i++) { > + if (!((page_num++) % WD_INTERVAL_PAGE)) > + touch_nmi_watchdog(); > swsusp_set_page_free(pfn_to_page(pfn + i)); > + } > } > } > spin_unlock_irqrestore(&zone->lock, flags); > -- > 2.7.4 > > -- > 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 -- Michal Hocko SUSE Labs -- 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