path: root/mm
diff options
authorMel Gorman <mgorman@techsingularity.net>2016-08-04 15:31:49 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-08-04 20:02:09 -0400
commitb4911ea2bcf52345bf3dc73292b8c4676f6192c6 (patch)
tree8afaeb68362a0c5b9fd429fe212d5c70a1089f21 /mm
parent412d0008d69ce964ac60ac9da714edb40bbae244 (diff)
mm: initialise per_cpu_nodestats for all online pgdats at boot
Paul Mackerras and Reza Arbab reported that machines with memoryless nodes fail when vmstats are refreshed. Paul reported an oops as follows Unable to handle kernel paging request for data at address 0xff7a10000 Faulting instruction address: 0xc000000000270cd0 Oops: Kernel access of bad area, sig: 11 [#1] SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.7.0-kvm+ #118 task: c000000ff0680010 task.stack: c000000ff0704000 NIP: c000000000270cd0 LR: c000000000270ce8 CTR: 0000000000000000 REGS: c000000ff0707900 TRAP: 0300 Not tainted (4.7.0-kvm+) MSR: 9000000102009033 <SF,HV,VEC,EE,ME,IR,DR,RI,LE,TM[E]> CR: 846b6824 XER: 20000000 CFAR: c000000000008768 DAR: 0000000ff7a10000 DSISR: 42000000 SOFTE: 1 NIP refresh_zone_stat_thresholds+0x80/0x240 LR refresh_zone_stat_thresholds+0x98/0x240 Call Trace: refresh_zone_stat_thresholds+0xb8/0x240 (unreliable) Both supplied potential fixes but one potentially misses checks and another had redundant initialisations. This version initialises per_cpu_nodestats on a per-pgdat basis instead of on a per-zone basis. Link: http://lkml.kernel.org/r/20160804092404.GI2799@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Reported-by: Paul Mackerras <paulus@ozlabs.org> Reported-by: Reza Arbab <arbab@linux.vnet.ibm.com> Tested-by: Reza Arbab <arbab@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
1 files changed, 5 insertions, 5 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 39a372a2a1d6..fb975cec3518 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5257,11 +5257,6 @@ static void __meminit setup_zone_pageset(struct zone *zone)
zone->pageset = alloc_percpu(struct per_cpu_pageset);
zone_pageset_init(zone, cpu);
- if (!zone->zone_pgdat->per_cpu_nodestats) {
- zone->zone_pgdat->per_cpu_nodestats =
- alloc_percpu(struct per_cpu_nodestat);
- }
@@ -5270,10 +5265,15 @@ static void __meminit setup_zone_pageset(struct zone *zone)
void __init setup_per_cpu_pageset(void)
+ struct pglist_data *pgdat;
struct zone *zone;
+ for_each_online_pgdat(pgdat)
+ pgdat->per_cpu_nodestats =
+ alloc_percpu(struct per_cpu_nodestat);
static noinline __ref