Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756521Ab3FKWNs (ORCPT ); Tue, 11 Jun 2013 18:13:48 -0400 Received: from e38.co.us.ibm.com ([32.97.110.159]:56874 "EHLO e38.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756432Ab3FKWNq (ORCPT ); Tue, 11 Jun 2013 18:13:46 -0400 From: Cody P Schafer To: Andrew Morton Cc: LKML , Linux MM , Valdis.Kletnieks@vt.edu, 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> X-Mailer: git-send-email 1.8.3 X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13061122-5518-0000-0000-00000F8EB82D Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2298 Lines: 70 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 from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/