From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx155.postini.com [74.125.245.155]) by kanga.kvack.org (Postfix) with SMTP id 4B47A6B0034 for ; Tue, 11 Jun 2013 18:13:45 -0400 (EDT) Received: from /spool/local by e35.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 11 Jun 2013 16:13:44 -0600 Received: from d03relay02.boulder.ibm.com (d03relay02.boulder.ibm.com [9.17.195.227]) by d03dlp01.boulder.ibm.com (Postfix) with ESMTP id C24071FF001B for ; Tue, 11 Jun 2013 16:08:28 -0600 (MDT) Received: from d03av04.boulder.ibm.com (d03av04.boulder.ibm.com [9.17.195.170]) by d03relay02.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r5BMDeFk163018 for ; Tue, 11 Jun 2013 16:13:40 -0600 Received: from d03av04.boulder.ibm.com (loopback [127.0.0.1]) by d03av04.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r5BMDdMR002578 for ; Tue, 11 Jun 2013 16:13:39 -0600 From: Cody P Schafer Subject: [PATCH] mm/page_alloc: don't re-init pageset in zone_pcp_update() Date: Tue, 11 Jun 2013 15:12:59 -0700 Message-Id: <1370988779-7586-1-git-send-email-cody@linux.vnet.ibm.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: LKML , Linux MM , Valdis.Kletnieks@vt.edu, Cody P Schafer Factor pageset_set_high_and_batch() (which contains all needed logic too set a pageset's ->high and ->batch inrespective of system state) out of zone_pageset_init(), which avoids us calling pageset_init(), and unsafely blowing away a pageset at runtime (leaked pages and potentially some funky allocations would be the result) when memory hotplug is triggered. Signed-off-by: Cody P Schafer --- Unless memory hotplug is being triggered on boot, this should *not* be cause of Valdis Kletnieks' reported bug in -next: "next-20130607 BUG: Bad page state in process systemd pfn:127643" --- mm/page_alloc.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 18102e1..f62c7ac 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -4111,11 +4111,9 @@ static void pageset_set_high(struct per_cpu_pageset *p, pageset_update(&p->pcp, high, batch); } -static void __meminit zone_pageset_init(struct zone *zone, int cpu) +static void __meminit pageset_set_high_and_batch(struct zone *zone, + struct per_cpu_pageset *pcp) { - struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu); - - pageset_init(pcp); if (percpu_pagelist_fraction) pageset_set_high(pcp, (zone->managed_pages / @@ -4124,6 +4122,14 @@ static void __meminit zone_pageset_init(struct zone *zone, int cpu) pageset_set_batch(pcp, zone_batchsize(zone)); } +static void __meminit zone_pageset_init(struct zone *zone, int cpu) +{ + struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu); + + pageset_init(pcp); + pageset_set_high_and_batch(zone, pcp); +} + static void __meminit setup_zone_pageset(struct zone *zone) { int cpu; @@ -6173,7 +6179,8 @@ void __meminit zone_pcp_update(struct zone *zone) unsigned cpu; mutex_lock(&pcp_batch_high_lock); for_each_possible_cpu(cpu) - zone_pageset_init(zone, cpu); + pageset_set_high_and_batch(zone, + per_cpu_ptr(zone->pageset, cpu)); mutex_unlock(&pcp_batch_high_lock); } #endif -- 1.8.3 -- 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