* mm: Initialise per_cpu_nodestats for all online pgdats at boot
@ 2016-08-04 9:24 Mel Gorman
2016-08-04 15:45 ` Reza Arbab
` (2 more replies)
0 siblings, 3 replies; 8+ messages in thread
From: Mel Gorman @ 2016-08-04 9:24 UTC (permalink / raw)
To: Andrew Morton
Cc: Reza Arbab, Paul Mackerras, linux-mm, linux-kernel, linuxppc-dev
Paul Mackerras and Reza Arbab reported that machines with memoryless nodes
fails when vmstats are refreshed. Paul reported an oops as follows
[ 1.713998] Unable to handle kernel paging request for data at address 0xff7a10000
[ 1.714164] Faulting instruction address: 0xc000000000270cd0
[ 1.714304] Oops: Kernel access of bad area, sig: 11 [#1]
[ 1.714414] SMP NR_CPUS=2048 NUMA PowerNV
[ 1.714530] Modules linked in:
[ 1.714647] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.7.0-kvm+ #118
[ 1.714786] task: c000000ff0680010 task.stack: c000000ff0704000
[ 1.714926] NIP: c000000000270cd0 LR: c000000000270ce8 CTR: 0000000000000000
[ 1.715093] REGS: c000000ff0707900 TRAP: 0300 Not tainted (4.7.0-kvm+)
[ 1.715232] MSR: 9000000102009033 <SF,HV,VEC,EE,ME,IR,DR,RI,LE,TM[E]> CR: 846b6824 XER: 20000000
[ 1.715748] CFAR: c000000000008768 DAR: 0000000ff7a10000 DSISR: 42000000 SOFTE: 1
GPR00: c000000000270d08 c000000ff0707b80 c0000000011fb200 0000000000000000
GPR04: 0000000000000800 0000000000000000 0000000000000000 0000000000000000
GPR08: ffffffffffffffff 0000000000000000 0000000ff7a10000 c00000000122aae0
GPR12: c000000000a1e440 c00000000fb80000 c00000000000c188 0000000000000000
GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR20: 0000000000000000 0000000000000000 0000000000000000 c000000000cecad0
GPR24: c000000000d035b8 c000000000d6cd18 c000000000d6cd18 c000001fffa86300
GPR28: 0000000000000000 c000001fffa96300 c000000001230034 c00000000122eb18
[ 1.717484] NIP [c000000000270cd0] refresh_zone_stat_thresholds+0x80/0x240
[ 1.717568] LR [c000000000270ce8] refresh_zone_stat_thresholds+0x98/0x240
[ 1.717648] Call Trace:
[ 1.717687] [c000000ff0707b80] [c000000000270d08] 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.
Reported-by: Paul Mackerras <paulus@ozlabs.org>
Reported-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
---
This has been compile-tested and boot-tested on a 32-bit KVM only. A
memoryless system was not available to test the patch with. A confirmation
from Paul and Reza that it resolves their problem is welcome.
mm/page_alloc.c | 10 +++++-----
1 file 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);
for_each_possible_cpu(cpu)
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_populated_zone(zone)
setup_zone_pageset(zone);
+
+ for_each_online_pgdat(pgdat)
+ pgdat->per_cpu_nodestats =
+ alloc_percpu(struct per_cpu_nodestat);
}
static noinline __ref
--
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^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: mm: Initialise per_cpu_nodestats for all online pgdats at boot
2016-08-04 9:24 mm: Initialise per_cpu_nodestats for all online pgdats at boot Mel Gorman
@ 2016-08-04 15:45 ` Reza Arbab
2016-08-05 3:22 ` Paul Mackerras
2016-08-10 17:59 ` Reza Arbab
2 siblings, 0 replies; 8+ messages in thread
From: Reza Arbab @ 2016-08-04 15:45 UTC (permalink / raw)
To: Mel Gorman
Cc: Andrew Morton, Paul Mackerras, linux-mm, linux-kernel, linuxppc-dev
On Thu, Aug 04, 2016 at 10:24:04AM +0100, Mel Gorman wrote:
>This has been compile-tested and boot-tested on a 32-bit KVM only. A
>memoryless system was not available to test the patch with. A confirmation
>from Paul and Reza that it resolves their problem is welcome.
Works for me. Thanks, Mel!
Tested-by: Reza Arbab <arbab@linux.vnet.ibm.com>
--
Reza Arbab
--
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^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: mm: Initialise per_cpu_nodestats for all online pgdats at boot
2016-08-04 9:24 mm: Initialise per_cpu_nodestats for all online pgdats at boot Mel Gorman
2016-08-04 15:45 ` Reza Arbab
@ 2016-08-05 3:22 ` Paul Mackerras
2016-08-10 17:59 ` Reza Arbab
2 siblings, 0 replies; 8+ messages in thread
From: Paul Mackerras @ 2016-08-05 3:22 UTC (permalink / raw)
To: Mel Gorman
Cc: Andrew Morton, Reza Arbab, linux-mm, linux-kernel, linuxppc-dev
On Thu, Aug 04, 2016 at 10:24:04AM +0100, Mel Gorman wrote:
> Paul Mackerras and Reza Arbab reported that machines with memoryless nodes
> fails when vmstats are refreshed. Paul reported an oops as follows
>
> [ 1.713998] Unable to handle kernel paging request for data at address 0xff7a10000
> [ 1.714164] Faulting instruction address: 0xc000000000270cd0
> [ 1.714304] Oops: Kernel access of bad area, sig: 11 [#1]
> [ 1.714414] SMP NR_CPUS=2048 NUMA PowerNV
> [ 1.714530] Modules linked in:
> [ 1.714647] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.7.0-kvm+ #118
> [ 1.714786] task: c000000ff0680010 task.stack: c000000ff0704000
> [ 1.714926] NIP: c000000000270cd0 LR: c000000000270ce8 CTR: 0000000000000000
> [ 1.715093] REGS: c000000ff0707900 TRAP: 0300 Not tainted (4.7.0-kvm+)
> [ 1.715232] MSR: 9000000102009033 <SF,HV,VEC,EE,ME,IR,DR,RI,LE,TM[E]> CR: 846b6824 XER: 20000000
> [ 1.715748] CFAR: c000000000008768 DAR: 0000000ff7a10000 DSISR: 42000000 SOFTE: 1
> GPR00: c000000000270d08 c000000ff0707b80 c0000000011fb200 0000000000000000
> GPR04: 0000000000000800 0000000000000000 0000000000000000 0000000000000000
> GPR08: ffffffffffffffff 0000000000000000 0000000ff7a10000 c00000000122aae0
> GPR12: c000000000a1e440 c00000000fb80000 c00000000000c188 0000000000000000
> GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
> GPR20: 0000000000000000 0000000000000000 0000000000000000 c000000000cecad0
> GPR24: c000000000d035b8 c000000000d6cd18 c000000000d6cd18 c000001fffa86300
> GPR28: 0000000000000000 c000001fffa96300 c000000001230034 c00000000122eb18
> [ 1.717484] NIP [c000000000270cd0] refresh_zone_stat_thresholds+0x80/0x240
> [ 1.717568] LR [c000000000270ce8] refresh_zone_stat_thresholds+0x98/0x240
> [ 1.717648] Call Trace:
> [ 1.717687] [c000000ff0707b80] [c000000000270d08] 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.
>
> Reported-by: Paul Mackerras <paulus@ozlabs.org>
> Reported-by: Reza Arbab <arbab@linux.vnet.ibm.com>
> Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
That works, thanks.
Tested-by: Paul Mackerras <paulus@ozlabs.org>
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^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: mm: Initialise per_cpu_nodestats for all online pgdats at boot
2016-08-04 9:24 mm: Initialise per_cpu_nodestats for all online pgdats at boot Mel Gorman
2016-08-04 15:45 ` Reza Arbab
2016-08-05 3:22 ` Paul Mackerras
@ 2016-08-10 17:59 ` Reza Arbab
2016-08-11 9:28 ` Mel Gorman
2 siblings, 1 reply; 8+ messages in thread
From: Reza Arbab @ 2016-08-10 17:59 UTC (permalink / raw)
To: Mel Gorman
Cc: Andrew Morton, Paul Mackerras, linux-mm, linux-kernel, linuxppc-dev
On Thu, Aug 04, 2016 at 10:24:04AM +0100, Mel Gorman wrote:
>[ 1.713998] Unable to handle kernel paging request for data at address 0xff7a10000
>[ 1.714164] Faulting instruction address: 0xc000000000270cd0
>[ 1.714304] Oops: Kernel access of bad area, sig: 11 [#1]
>[ 1.714414] SMP NR_CPUS=2048 NUMA PowerNV
>[ 1.714530] Modules linked in:
>[ 1.714647] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.7.0-kvm+ #118
>[ 1.714786] task: c000000ff0680010 task.stack: c000000ff0704000
>[ 1.714926] NIP: c000000000270cd0 LR: c000000000270ce8 CTR: 0000000000000000
>[ 1.715093] REGS: c000000ff0707900 TRAP: 0300 Not tainted (4.7.0-kvm+)
>[ 1.715232] MSR: 9000000102009033 <SF,HV,VEC,EE,ME,IR,DR,RI,LE,TM[E]> CR: 846b6824 XER: 20000000
>[ 1.715748] CFAR: c000000000008768 DAR: 0000000ff7a10000 DSISR: 42000000 SOFTE: 1
>GPR00: c000000000270d08 c000000ff0707b80 c0000000011fb200 0000000000000000
>GPR04: 0000000000000800 0000000000000000 0000000000000000 0000000000000000
>GPR08: ffffffffffffffff 0000000000000000 0000000ff7a10000 c00000000122aae0
>GPR12: c000000000a1e440 c00000000fb80000 c00000000000c188 0000000000000000
>GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
>GPR20: 0000000000000000 0000000000000000 0000000000000000 c000000000cecad0
>GPR24: c000000000d035b8 c000000000d6cd18 c000000000d6cd18 c000001fffa86300
>GPR28: 0000000000000000 c000001fffa96300 c000000001230034 c00000000122eb18
>[ 1.717484] NIP [c000000000270cd0] refresh_zone_stat_thresholds+0x80/0x240
>[ 1.717568] LR [c000000000270ce8] refresh_zone_stat_thresholds+0x98/0x240
>[ 1.717648] Call Trace:
>[ 1.717687] [c000000ff0707b80] [c000000000270d08] refresh_zone_stat_thresholds+0xb8/0x240 (unreliable)
I've been investigating node hotplug. That path is also going to require
initialization of per_cpu_nodestats. This worked for me:
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 3894b65..41266dc 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1219,6 +1219,7 @@ static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
/* init node's zones as empty zones, we don't have any present pages.*/
free_area_init_node(nid, zones_size, start_pfn, zholes_size);
+ pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat);
/*
* The node we allocated has no zone fallback lists. For avoiding
@@ -1249,6 +1250,7 @@ static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
static void rollback_node_hotadd(int nid, pg_data_t *pgdat)
{
arch_refresh_nodedata(nid, NULL);
+ free_percpu(pgdat->per_cpu_nodestats);
arch_free_nodedata(pgdat);
return;
}
--
Reza Arbab
--
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^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: mm: Initialise per_cpu_nodestats for all online pgdats at boot
2016-08-10 17:59 ` Reza Arbab
@ 2016-08-11 9:28 ` Mel Gorman
2016-08-11 15:47 ` Reza Arbab
2016-08-11 16:04 ` [PATCH] mm: Initialize per_cpu_nodestats for hotadded pgdats Reza Arbab
0 siblings, 2 replies; 8+ messages in thread
From: Mel Gorman @ 2016-08-11 9:28 UTC (permalink / raw)
To: Reza Arbab
Cc: Andrew Morton, Paul Mackerras, linux-mm, linux-kernel, linuxppc-dev
On Wed, Aug 10, 2016 at 12:59:40PM -0500, Reza Arbab wrote:
> On Thu, Aug 04, 2016 at 10:24:04AM +0100, Mel Gorman wrote:
> >[ 1.713998] Unable to handle kernel paging request for data at address 0xff7a10000
> >[ 1.714164] Faulting instruction address: 0xc000000000270cd0
> >[ 1.714304] Oops: Kernel access of bad area, sig: 11 [#1]
> >[ 1.714414] SMP NR_CPUS=2048 NUMA PowerNV
> >[ 1.714530] Modules linked in:
> >[ 1.714647] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.7.0-kvm+ #118
> >[ 1.714786] task: c000000ff0680010 task.stack: c000000ff0704000
> >[ 1.714926] NIP: c000000000270cd0 LR: c000000000270ce8 CTR: 0000000000000000
> >[ 1.715093] REGS: c000000ff0707900 TRAP: 0300 Not tainted (4.7.0-kvm+)
> >[ 1.715232] MSR: 9000000102009033 <SF,HV,VEC,EE,ME,IR,DR,RI,LE,TM[E]> CR: 846b6824 XER: 20000000
> >[ 1.715748] CFAR: c000000000008768 DAR: 0000000ff7a10000 DSISR: 42000000 SOFTE: 1
> >GPR00: c000000000270d08 c000000ff0707b80 c0000000011fb200 0000000000000000
> >GPR04: 0000000000000800 0000000000000000 0000000000000000 0000000000000000
> >GPR08: ffffffffffffffff 0000000000000000 0000000ff7a10000 c00000000122aae0
> >GPR12: c000000000a1e440 c00000000fb80000 c00000000000c188 0000000000000000
> >GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
> >GPR20: 0000000000000000 0000000000000000 0000000000000000 c000000000cecad0
> >GPR24: c000000000d035b8 c000000000d6cd18 c000000000d6cd18 c000001fffa86300
> >GPR28: 0000000000000000 c000001fffa96300 c000000001230034 c00000000122eb18
> >[ 1.717484] NIP [c000000000270cd0] refresh_zone_stat_thresholds+0x80/0x240
> >[ 1.717568] LR [c000000000270ce8] refresh_zone_stat_thresholds+0x98/0x240
> >[ 1.717648] Call Trace:
> >[ 1.717687] [c000000ff0707b80] [c000000000270d08] refresh_zone_stat_thresholds+0xb8/0x240 (unreliable)
>
> I've been investigating node hotplug. That path is also going to require
> initialization of per_cpu_nodestats. This worked for me:
>
Fix looks ok. Can you add a proper changelog to it including an example
oops or do you need me to do it?
--
Mel Gorman
SUSE Labs
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^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: mm: Initialise per_cpu_nodestats for all online pgdats at boot
2016-08-11 9:28 ` Mel Gorman
@ 2016-08-11 15:47 ` Reza Arbab
2016-08-11 16:04 ` [PATCH] mm: Initialize per_cpu_nodestats for hotadded pgdats Reza Arbab
1 sibling, 0 replies; 8+ messages in thread
From: Reza Arbab @ 2016-08-11 15:47 UTC (permalink / raw)
To: Mel Gorman
Cc: Andrew Morton, Paul Mackerras, linux-mm, linux-kernel, linuxppc-dev
On Thu, Aug 11, 2016 at 10:28:08AM +0100, Mel Gorman wrote:
>Fix looks ok. Can you add a proper changelog to it including an example
>oops or do you need me to do it?
Sure, no problem. Patch to follow.
--
Reza Arbab
--
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^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH] mm: Initialize per_cpu_nodestats for hotadded pgdats
2016-08-11 9:28 ` Mel Gorman
2016-08-11 15:47 ` Reza Arbab
@ 2016-08-11 16:04 ` Reza Arbab
2016-08-12 2:07 ` Balbir Singh
1 sibling, 1 reply; 8+ messages in thread
From: Reza Arbab @ 2016-08-11 16:04 UTC (permalink / raw)
To: Mel Gorman, Andrew Morton, Paul Mackerras, linux-mm,
linux-kernel, linuxppc-dev
The following oops occurs after a pgdat is hotadded:
[ 86.839956] Unable to handle kernel paging request for data at address 0x00c30001
[ 86.840132] Faulting instruction address: 0xc00000000022f8f4
[ 86.840328] Oops: Kernel access of bad area, sig: 11 [#1]
[ 86.840468] SMP NR_CPUS=2048 NUMA pSeries
[ 86.840612] Modules linked in: ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw iptable_filter nls_utf8 isofs sg virtio_balloon uio_pdrv_genirq uio ip_tables xfs libcrc32c sr_mod cdrom sd_mod virtio_net ibmvscsi scsi_transport_srp virtio_pci virtio_ring virtio dm_mirror dm_region_hash dm_log dm_mod
[ 86.842955] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W 4.8.0-rc1-device #110
[ 86.843140] task: c000000000ef3080 task.stack: c000000000f6c000
[ 86.843323] NIP: c00000000022f8f4 LR: c00000000022f948 CTR: 0000000000000000
[ 86.843595] REGS: c000000000f6fa50 TRAP: 0300 Tainted: G W (4.8.0-rc1-device)
[ 86.843889] MSR: 800000010280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE,TM[E]> CR: 84002028 XER: 20000000
[ 86.844624] CFAR: d000000001d2013c DAR: 0000000000c30001 DSISR: 40000000 SOFTE: 0
GPR00: c00000000022f948 c000000000f6fcd0 c000000000f71400 0000000000000001
GPR04: 0000000000000100 0000000000000000 0000000000000000 0000000000c30000
GPR08: ffffffffffffffff 0000000000000001 0000000000c30000 00000000ffffffff
GPR12: 0000000000002200 c000000001300000 c000000000faefb4 c000000000faefa8
GPR16: c000000000f6c000 c000000000f6c080 c000000000bf15b0 c000000000f6c080
GPR20: c000000000bf4928 0000000000000000 0000000000000003 c000000000bf4968
GPR24: c0000000ffed0000 0000000000000000 0000000000000000 c000000000f6fd58
GPR28: 0000000000000001 0000000000000001 c000000000f6fcf0 c0000000ffed9c08
[ 86.847747] NIP [c00000000022f8f4] refresh_cpu_vm_stats+0x1a4/0x2f0
[ 86.847897] LR [c00000000022f948] refresh_cpu_vm_stats+0x1f8/0x2f0
[ 86.848060] Call Trace:
[ 86.848183] [c000000000f6fcd0] [c00000000022f948] refresh_cpu_vm_stats+0x1f8/0x2f0 (unreliable)
Add per_cpu_nodestats initialization to the hotplug codepath.
Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
---
mm/memory_hotplug.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 3894b65..41266dc 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1219,6 +1219,7 @@ static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
/* init node's zones as empty zones, we don't have any present pages.*/
free_area_init_node(nid, zones_size, start_pfn, zholes_size);
+ pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat);
/*
* The node we allocated has no zone fallback lists. For avoiding
@@ -1249,6 +1250,7 @@ static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
static void rollback_node_hotadd(int nid, pg_data_t *pgdat)
{
arch_refresh_nodedata(nid, NULL);
+ free_percpu(pgdat->per_cpu_nodestats);
arch_free_nodedata(pgdat);
return;
}
--
1.8.3.1
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^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [PATCH] mm: Initialize per_cpu_nodestats for hotadded pgdats
2016-08-11 16:04 ` [PATCH] mm: Initialize per_cpu_nodestats for hotadded pgdats Reza Arbab
@ 2016-08-12 2:07 ` Balbir Singh
0 siblings, 0 replies; 8+ messages in thread
From: Balbir Singh @ 2016-08-12 2:07 UTC (permalink / raw)
To: Reza Arbab, Mel Gorman, Andrew Morton, Paul Mackerras, linux-mm,
linux-kernel, linuxppc-dev
On 12/08/16 02:04, Reza Arbab wrote:
> The following oops occurs after a pgdat is hotadded:
>
> [ 86.839956] Unable to handle kernel paging request for data at address 0x00c30001
> [ 86.840132] Faulting instruction address: 0xc00000000022f8f4
> [ 86.840328] Oops: Kernel access of bad area, sig: 11 [#1]
> [ 86.840468] SMP NR_CPUS=2048 NUMA pSeries
> [ 86.840612] Modules linked in: ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw iptable_filter nls_utf8 isofs sg virtio_balloon uio_pdrv_genirq uio ip_tables xfs libcrc32c sr_mod cdrom sd_mod virtio_net ibmvscsi scsi_transport_srp virtio_pci virtio_ring virtio dm_mirror dm_region_hash dm_log dm_mod
> [ 86.842955] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W 4.8.0-rc1-device #110
> [ 86.843140] task: c000000000ef3080 task.stack: c000000000f6c000
> [ 86.843323] NIP: c00000000022f8f4 LR: c00000000022f948 CTR: 0000000000000000
> [ 86.843595] REGS: c000000000f6fa50 TRAP: 0300 Tainted: G W (4.8.0-rc1-device)
> [ 86.843889] MSR: 800000010280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE,TM[E]> CR: 84002028 XER: 20000000
> [ 86.844624] CFAR: d000000001d2013c DAR: 0000000000c30001 DSISR: 40000000 SOFTE: 0
> GPR00: c00000000022f948 c000000000f6fcd0 c000000000f71400 0000000000000001
> GPR04: 0000000000000100 0000000000000000 0000000000000000 0000000000c30000
> GPR08: ffffffffffffffff 0000000000000001 0000000000c30000 00000000ffffffff
> GPR12: 0000000000002200 c000000001300000 c000000000faefb4 c000000000faefa8
> GPR16: c000000000f6c000 c000000000f6c080 c000000000bf15b0 c000000000f6c080
> GPR20: c000000000bf4928 0000000000000000 0000000000000003 c000000000bf4968
> GPR24: c0000000ffed0000 0000000000000000 0000000000000000 c000000000f6fd58
> GPR28: 0000000000000001 0000000000000001 c000000000f6fcf0 c0000000ffed9c08
> [ 86.847747] NIP [c00000000022f8f4] refresh_cpu_vm_stats+0x1a4/0x2f0
> [ 86.847897] LR [c00000000022f948] refresh_cpu_vm_stats+0x1f8/0x2f0
> [ 86.848060] Call Trace:
> [ 86.848183] [c000000000f6fcd0] [c00000000022f948] refresh_cpu_vm_stats+0x1f8/0x2f0 (unreliable)
>
> Add per_cpu_nodestats initialization to the hotplug codepath.
>
> Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
> ---
> mm/memory_hotplug.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
> index 3894b65..41266dc 100644
> --- a/mm/memory_hotplug.c
> +++ b/mm/memory_hotplug.c
> @@ -1219,6 +1219,7 @@ static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
>
> /* init node's zones as empty zones, we don't have any present pages.*/
> free_area_init_node(nid, zones_size, start_pfn, zholes_size);
> + pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat);
>
> /*
> * The node we allocated has no zone fallback lists. For avoiding
> @@ -1249,6 +1250,7 @@ static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
> static void rollback_node_hotadd(int nid, pg_data_t *pgdat)
> {
> arch_refresh_nodedata(nid, NULL);
> + free_percpu(pgdat->per_cpu_nodestats);
> arch_free_nodedata(pgdat);
> return;
> }
>
I wonder if node_set_online() should do the allocation and offline should free.
But that would be a larger change
Balbir
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^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2016-08-12 2:08 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-08-04 9:24 mm: Initialise per_cpu_nodestats for all online pgdats at boot Mel Gorman
2016-08-04 15:45 ` Reza Arbab
2016-08-05 3:22 ` Paul Mackerras
2016-08-10 17:59 ` Reza Arbab
2016-08-11 9:28 ` Mel Gorman
2016-08-11 15:47 ` Reza Arbab
2016-08-11 16:04 ` [PATCH] mm: Initialize per_cpu_nodestats for hotadded pgdats Reza Arbab
2016-08-12 2:07 ` Balbir Singh
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