Re: [PATCH v2 1/5] mm: migrate NUMA stats from per-zone to per-node

[kemi <kemi.wang@intel.com>]

On 2017年12月19日 20:28, Michal Hocko wrote:
> On Tue 19-12-17 14:39:22, Kemi Wang wrote:
>> There is not really any use to get NUMA stats separated by zone, and
>> current per-zone NUMA stats is only consumed in /proc/zoneinfo. For code
>> cleanup purpose, we move NUMA stats from per-zone to per-node and reuse the
>> existed per-cpu infrastructure.
> 
> Let's hope that nobody really depends on the per-zone numbers. It would
> be really strange as those counters are inherently per-node and that is
> what users should care about but who knows...
> 
> Anyway, I hoped we could get rid of NR_VM_NUMA_STAT_ITEMS but your patch
> keeps it and follow up patches even use it further. I will comment on
> those separately but this still makes these few counters really special
> which I think is wrong.
> 

Well, that's what I can think of to keep a balance between performance 
and simplification. If you have a better idea, please post it and 
I will follow that surely.
 
>> Suggested-by: Andi Kleen <ak@linux.intel.com>
>> Suggested-by: Michal Hocko <mhocko@kernel.com>
>> Signed-off-by: Kemi Wang <kemi.wang@intel.com>
> 
> I have to fully grasp the rest of the series before I'll give my Ack,
> but I _really_ like the simplification this adds to the code. I believe
> it can be even simpler.
> 
>> ---
>>  drivers/base/node.c    |  23 +++----
>>  include/linux/mmzone.h |  27 ++++----
>>  include/linux/vmstat.h |  31 ---------
>>  mm/mempolicy.c         |   2 +-
>>  mm/page_alloc.c        |  16 +++--
>>  mm/vmstat.c            | 177 +++++--------------------------------------------
>>  6 files changed, 46 insertions(+), 230 deletions(-)
>>
>> diff --git a/drivers/base/node.c b/drivers/base/node.c
>> index ee090ab..a045ea1 100644
>> --- a/drivers/base/node.c
>> +++ b/drivers/base/node.c
>> @@ -169,13 +169,14 @@ static ssize_t node_read_numastat(struct device *dev,
>>  		       "interleave_hit %lu\n"
>>  		       "local_node %lu\n"
>>  		       "other_node %lu\n",
>> -		       sum_zone_numa_state(dev->id, NUMA_HIT),
>> -		       sum_zone_numa_state(dev->id, NUMA_MISS),
>> -		       sum_zone_numa_state(dev->id, NUMA_FOREIGN),
>> -		       sum_zone_numa_state(dev->id, NUMA_INTERLEAVE_HIT),
>> -		       sum_zone_numa_state(dev->id, NUMA_LOCAL),
>> -		       sum_zone_numa_state(dev->id, NUMA_OTHER));
>> +		       node_page_state(NODE_DATA(dev->id), NUMA_HIT),
>> +		       node_page_state(NODE_DATA(dev->id), NUMA_MISS),
>> +		       node_page_state(NODE_DATA(dev->id), NUMA_FOREIGN),
>> +		       node_page_state(NODE_DATA(dev->id), NUMA_INTERLEAVE_HIT),
>> +		       node_page_state(NODE_DATA(dev->id), NUMA_LOCAL),
>> +		       node_page_state(NODE_DATA(dev->id), NUMA_OTHER));
>>  }
>> +
>>  static DEVICE_ATTR(numastat, S_IRUGO, node_read_numastat, NULL);
>>  
>>  static ssize_t node_read_vmstat(struct device *dev,
>> @@ -190,17 +191,9 @@ static ssize_t node_read_vmstat(struct device *dev,
>>  		n += sprintf(buf+n, "%s %lu\n", vmstat_text[i],
>>  			     sum_zone_node_page_state(nid, i));
>>  
>> -#ifdef CONFIG_NUMA
>> -	for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++)
>> -		n += sprintf(buf+n, "%s %lu\n",
>> -			     vmstat_text[i + NR_VM_ZONE_STAT_ITEMS],
>> -			     sum_zone_numa_state(nid, i));
>> -#endif
>> -
>>  	for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
>>  		n += sprintf(buf+n, "%s %lu\n",
>> -			     vmstat_text[i + NR_VM_ZONE_STAT_ITEMS +
>> -			     NR_VM_NUMA_STAT_ITEMS],
>> +			     vmstat_text[i + NR_VM_ZONE_STAT_ITEMS],
>>  			     node_page_state(pgdat, i));
>>  
>>  	return n;
>> diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
>> index 67f2e3c..c06d880 100644
>> --- a/include/linux/mmzone.h
>> +++ b/include/linux/mmzone.h
>> @@ -115,20 +115,6 @@ struct zone_padding {
>>  #define ZONE_PADDING(name)
>>  #endif
>>  
>> -#ifdef CONFIG_NUMA
>> -enum numa_stat_item {
>> -	NUMA_HIT,		/* allocated in intended node */
>> -	NUMA_MISS,		/* allocated in non intended node */
>> -	NUMA_FOREIGN,		/* was intended here, hit elsewhere */
>> -	NUMA_INTERLEAVE_HIT,	/* interleaver preferred this zone */
>> -	NUMA_LOCAL,		/* allocation from local node */
>> -	NUMA_OTHER,		/* allocation from other node */
>> -	NR_VM_NUMA_STAT_ITEMS
>> -};
>> -#else
>> -#define NR_VM_NUMA_STAT_ITEMS 0
>> -#endif
>> -
>>  enum zone_stat_item {
>>  	/* First 128 byte cacheline (assuming 64 bit words) */
>>  	NR_FREE_PAGES,
>> @@ -151,7 +137,18 @@ enum zone_stat_item {
>>  	NR_VM_ZONE_STAT_ITEMS };
>>  
>>  enum node_stat_item {
>> -	NR_LRU_BASE,
>> +#ifdef CONFIG_NUMA
>> +	NUMA_HIT,		/* allocated in intended node */
>> +	NUMA_MISS,		/* allocated in non intended node */
>> +	NUMA_FOREIGN,		/* was intended here, hit elsewhere */
>> +	NUMA_INTERLEAVE_HIT,	/* interleaver preferred this zone */
>> +	NUMA_LOCAL,		/* allocation from local node */
>> +	NUMA_OTHER,		/* allocation from other node */
>> +	NR_VM_NUMA_STAT_ITEMS,
>> +#else
>> +#define	NR_VM_NUMA_STAT_ITEMS 0
>> +#endif
>> +	NR_LRU_BASE = NR_VM_NUMA_STAT_ITEMS,
>>  	NR_INACTIVE_ANON = NR_LRU_BASE, /* must match order of LRU_[IN]ACTIVE */
>>  	NR_ACTIVE_ANON,		/*  "     "     "   "       "         */
>>  	NR_INACTIVE_FILE,	/*  "     "     "   "       "         */
>> diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h
>> index 1779c98..80bf290 100644
>> --- a/include/linux/vmstat.h
>> +++ b/include/linux/vmstat.h
>> @@ -118,37 +118,8 @@ static inline void vm_events_fold_cpu(int cpu)
>>   * Zone and node-based page accounting with per cpu differentials.
>>   */
>>  extern atomic_long_t vm_zone_stat[NR_VM_ZONE_STAT_ITEMS];
>> -extern atomic_long_t vm_numa_stat[NR_VM_NUMA_STAT_ITEMS];
>>  extern atomic_long_t vm_node_stat[NR_VM_NODE_STAT_ITEMS];
>>  
>> -#ifdef CONFIG_NUMA
>> -static inline void zone_numa_state_add(long x, struct zone *zone,
>> -				 enum numa_stat_item item)
>> -{
>> -	atomic_long_add(x, &zone->vm_numa_stat[item]);
>> -	atomic_long_add(x, &vm_numa_stat[item]);
>> -}
>> -
>> -static inline unsigned long global_numa_state(enum numa_stat_item item)
>> -{
>> -	long x = atomic_long_read(&vm_numa_stat[item]);
>> -
>> -	return x;
>> -}
>> -
>> -static inline unsigned long zone_numa_state_snapshot(struct zone *zone,
>> -					enum numa_stat_item item)
>> -{
>> -	long x = atomic_long_read(&zone->vm_numa_stat[item]);
>> -	int cpu;
>> -
>> -	for_each_online_cpu(cpu)
>> -		x += per_cpu_ptr(zone->pageset, cpu)->vm_numa_stat_diff[item];
>> -
>> -	return x;
>> -}
>> -#endif /* CONFIG_NUMA */
>> -
>>  static inline void zone_page_state_add(long x, struct zone *zone,
>>  				 enum zone_stat_item item)
>>  {
>> @@ -234,10 +205,8 @@ static inline unsigned long node_page_state_snapshot(pg_data_t *pgdat,
>>  
>>  
>>  #ifdef CONFIG_NUMA
>> -extern void __inc_numa_state(struct zone *zone, enum numa_stat_item item);
>>  extern unsigned long sum_zone_node_page_state(int node,
>>  					      enum zone_stat_item item);
>> -extern unsigned long sum_zone_numa_state(int node, enum numa_stat_item item);
>>  extern unsigned long node_page_state(struct pglist_data *pgdat,
>>  						enum node_stat_item item);
>>  #else
>> diff --git a/mm/mempolicy.c b/mm/mempolicy.c
>> index 4ce44d3..b2293e3 100644
>> --- a/mm/mempolicy.c
>> +++ b/mm/mempolicy.c
>> @@ -1920,7 +1920,7 @@ static struct page *alloc_page_interleave(gfp_t gfp, unsigned order,
>>  		return page;
>>  	if (page && page_to_nid(page) == nid) {
>>  		preempt_disable();
>> -		__inc_numa_state(page_zone(page), NUMA_INTERLEAVE_HIT);
>> +		inc_node_state(page_pgdat(page), NUMA_INTERLEAVE_HIT);
>>  		preempt_enable();
>>  	}
>>  	return page;
>> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
>> index 7e5e775..81e8d8f 100644
>> --- a/mm/page_alloc.c
>> +++ b/mm/page_alloc.c
>> @@ -2793,22 +2793,24 @@ int __isolate_free_page(struct page *page, unsigned int order)
>>  static inline void zone_statistics(struct zone *preferred_zone, struct zone *z)
>>  {
>>  #ifdef CONFIG_NUMA
>> -	enum numa_stat_item local_stat = NUMA_LOCAL;
>> +	int preferred_nid = preferred_zone->node;
>> +	int nid = z->node;
>> +	enum node_stat_item local_stat = NUMA_LOCAL;
>>  
>>  	/* skip numa counters update if numa stats is disabled */
>>  	if (!static_branch_likely(&vm_numa_stat_key))
>>  		return;
>>  
>> -	if (z->node != numa_node_id())
>> +	if (nid != numa_node_id())
>>  		local_stat = NUMA_OTHER;
>>  
>> -	if (z->node == preferred_zone->node)
>> -		__inc_numa_state(z, NUMA_HIT);
>> +	if (nid == preferred_nid)
>> +		inc_node_state(NODE_DATA(nid), NUMA_HIT);
>>  	else {
>> -		__inc_numa_state(z, NUMA_MISS);
>> -		__inc_numa_state(preferred_zone, NUMA_FOREIGN);
>> +		inc_node_state(NODE_DATA(nid), NUMA_MISS);
>> +		inc_node_state(NODE_DATA(preferred_nid), NUMA_FOREIGN);
>>  	}
>> -	__inc_numa_state(z, local_stat);
>> +	inc_node_state(NODE_DATA(nid), local_stat);
>>  #endif
>>  }
>>  
>> diff --git a/mm/vmstat.c b/mm/vmstat.c
>> index 40b2db6..1dd12ae 100644
>> --- a/mm/vmstat.c
>> +++ b/mm/vmstat.c
>> @@ -30,46 +30,44 @@
>>  
>>  #include "internal.h"
>>  
>> -#define NUMA_STATS_THRESHOLD (U16_MAX - 2)
>> -
>>  #ifdef CONFIG_NUMA
>>  int sysctl_vm_numa_stat = ENABLE_NUMA_STAT;
>>  
>> -/* zero numa counters within a zone */
>> -static void zero_zone_numa_counters(struct zone *zone)
>> +/* zero numa stats within a node */
>> +static void zero_node_numa_stats(int node)
>>  {
>>  	int item, cpu;
>>  
>>  	for (item = 0; item < NR_VM_NUMA_STAT_ITEMS; item++) {
>> -		atomic_long_set(&zone->vm_numa_stat[item], 0);
>> +		atomic_long_set(&(NODE_DATA(node)->vm_stat[item]), 0);
>>  		for_each_online_cpu(cpu)
>> -			per_cpu_ptr(zone->pageset, cpu)->vm_numa_stat_diff[item]
>> -						= 0;
>> +			per_cpu_ptr(NODE_DATA(node)->per_cpu_nodestats,
>> +					cpu)->vm_node_stat_diff[item] = 0;
>>  	}
>>  }
>>  
>> -/* zero numa counters of all the populated zones */
>> -static void zero_zones_numa_counters(void)
>> +/* zero numa stats of all the online nodes */
>> +static void zero_nodes_numa_stats(void)
>>  {
>> -	struct zone *zone;
>> +	int node;
>>  
>> -	for_each_populated_zone(zone)
>> -		zero_zone_numa_counters(zone);
>> +	for_each_online_node(node)
>> +		zero_node_numa_stats(node);
>>  }
>>  
>> -/* zero global numa counters */
>> -static void zero_global_numa_counters(void)
>> +/* zero global numa stats */
>> +static void zero_global_numa_stats(void)
>>  {
>>  	int item;
>>  
>>  	for (item = 0; item < NR_VM_NUMA_STAT_ITEMS; item++)
>> -		atomic_long_set(&vm_numa_stat[item], 0);
>> +		atomic_long_set(&vm_node_stat[item], 0);
>>  }
>>  
>>  static void invalid_numa_statistics(void)
>>  {
>> -	zero_zones_numa_counters();
>> -	zero_global_numa_counters();
>> +	zero_nodes_numa_stats();
>> +	zero_global_numa_stats();
>>  }
>>  
>>  static DEFINE_MUTEX(vm_numa_stat_lock);
>> @@ -160,10 +158,8 @@ void vm_events_fold_cpu(int cpu)
>>   * vm_stat contains the global counters
>>   */
>>  atomic_long_t vm_zone_stat[NR_VM_ZONE_STAT_ITEMS] __cacheline_aligned_in_smp;
>> -atomic_long_t vm_numa_stat[NR_VM_NUMA_STAT_ITEMS] __cacheline_aligned_in_smp;
>>  atomic_long_t vm_node_stat[NR_VM_NODE_STAT_ITEMS] __cacheline_aligned_in_smp;
>>  EXPORT_SYMBOL(vm_zone_stat);
>> -EXPORT_SYMBOL(vm_numa_stat);
>>  EXPORT_SYMBOL(vm_node_stat);
>>  
>>  #ifdef CONFIG_SMP
>> @@ -679,32 +675,6 @@ EXPORT_SYMBOL(dec_node_page_state);
>>   * Fold a differential into the global counters.
>>   * Returns the number of counters updated.
>>   */
>> -#ifdef CONFIG_NUMA
>> -static int fold_diff(int *zone_diff, int *numa_diff, int *node_diff)
>> -{
>> -	int i;
>> -	int changes = 0;
>> -
>> -	for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
>> -		if (zone_diff[i]) {
>> -			atomic_long_add(zone_diff[i], &vm_zone_stat[i]);
>> -			changes++;
>> -	}
>> -
>> -	for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++)
>> -		if (numa_diff[i]) {
>> -			atomic_long_add(numa_diff[i], &vm_numa_stat[i]);
>> -			changes++;
>> -	}
>> -
>> -	for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
>> -		if (node_diff[i]) {
>> -			atomic_long_add(node_diff[i], &vm_node_stat[i]);
>> -			changes++;
>> -	}
>> -	return changes;
>> -}
>> -#else
>>  static int fold_diff(int *zone_diff, int *node_diff)
>>  {
>>  	int i;
>> @@ -723,7 +693,6 @@ static int fold_diff(int *zone_diff, int *node_diff)
>>  	}
>>  	return changes;
>>  }
>> -#endif /* CONFIG_NUMA */
>>  
>>  /*
>>   * Update the zone counters for the current cpu.
>> @@ -747,9 +716,6 @@ static int refresh_cpu_vm_stats(bool do_pagesets)
>>  	struct zone *zone;
>>  	int i;
>>  	int global_zone_diff[NR_VM_ZONE_STAT_ITEMS] = { 0, };
>> -#ifdef CONFIG_NUMA
>> -	int global_numa_diff[NR_VM_NUMA_STAT_ITEMS] = { 0, };
>> -#endif
>>  	int global_node_diff[NR_VM_NODE_STAT_ITEMS] = { 0, };
>>  	int changes = 0;
>>  
>> @@ -771,18 +737,6 @@ static int refresh_cpu_vm_stats(bool do_pagesets)
>>  			}
>>  		}
>>  #ifdef CONFIG_NUMA
>> -		for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++) {
>> -			int v;
>> -
>> -			v = this_cpu_xchg(p->vm_numa_stat_diff[i], 0);
>> -			if (v) {
>> -
>> -				atomic_long_add(v, &zone->vm_numa_stat[i]);
>> -				global_numa_diff[i] += v;
>> -				__this_cpu_write(p->expire, 3);
>> -			}
>> -		}
>> -
>>  		if (do_pagesets) {
>>  			cond_resched();
>>  			/*
>> @@ -829,12 +783,7 @@ static int refresh_cpu_vm_stats(bool do_pagesets)
>>  		}
>>  	}
>>  
>> -#ifdef CONFIG_NUMA
>> -	changes += fold_diff(global_zone_diff, global_numa_diff,
>> -			     global_node_diff);
>> -#else
>>  	changes += fold_diff(global_zone_diff, global_node_diff);
>> -#endif
>>  	return changes;
>>  }
>>  
>> @@ -849,9 +798,6 @@ void cpu_vm_stats_fold(int cpu)
>>  	struct zone *zone;
>>  	int i;
>>  	int global_zone_diff[NR_VM_ZONE_STAT_ITEMS] = { 0, };
>> -#ifdef CONFIG_NUMA
>> -	int global_numa_diff[NR_VM_NUMA_STAT_ITEMS] = { 0, };
>> -#endif
>>  	int global_node_diff[NR_VM_NODE_STAT_ITEMS] = { 0, };
>>  
>>  	for_each_populated_zone(zone) {
>> @@ -868,18 +814,6 @@ void cpu_vm_stats_fold(int cpu)
>>  				atomic_long_add(v, &zone->vm_stat[i]);
>>  				global_zone_diff[i] += v;
>>  			}
>> -
>> -#ifdef CONFIG_NUMA
>> -		for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++)
>> -			if (p->vm_numa_stat_diff[i]) {
>> -				int v;
>> -
>> -				v = p->vm_numa_stat_diff[i];
>> -				p->vm_numa_stat_diff[i] = 0;
>> -				atomic_long_add(v, &zone->vm_numa_stat[i]);
>> -				global_numa_diff[i] += v;
>> -			}
>> -#endif
>>  	}
>>  
>>  	for_each_online_pgdat(pgdat) {
>> @@ -898,11 +832,7 @@ void cpu_vm_stats_fold(int cpu)
>>  			}
>>  	}
>>  
>> -#ifdef CONFIG_NUMA
>> -	fold_diff(global_zone_diff, global_numa_diff, global_node_diff);
>> -#else
>>  	fold_diff(global_zone_diff, global_node_diff);
>> -#endif
>>  }
>>  
>>  /*
>> @@ -920,36 +850,10 @@ void drain_zonestat(struct zone *zone, struct per_cpu_pageset *pset)
>>  			atomic_long_add(v, &zone->vm_stat[i]);
>>  			atomic_long_add(v, &vm_zone_stat[i]);
>>  		}
>> -
>> -#ifdef CONFIG_NUMA
>> -	for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++)
>> -		if (pset->vm_numa_stat_diff[i]) {
>> -			int v = pset->vm_numa_stat_diff[i];
>> -
>> -			pset->vm_numa_stat_diff[i] = 0;
>> -			atomic_long_add(v, &zone->vm_numa_stat[i]);
>> -			atomic_long_add(v, &vm_numa_stat[i]);
>> -		}
>> -#endif
>>  }
>>  #endif
>>  
>>  #ifdef CONFIG_NUMA
>> -void __inc_numa_state(struct zone *zone,
>> -				 enum numa_stat_item item)
>> -{
>> -	struct per_cpu_pageset __percpu *pcp = zone->pageset;
>> -	u16 __percpu *p = pcp->vm_numa_stat_diff + item;
>> -	u16 v;
>> -
>> -	v = __this_cpu_inc_return(*p);
>> -
>> -	if (unlikely(v > NUMA_STATS_THRESHOLD)) {
>> -		zone_numa_state_add(v, zone, item);
>> -		__this_cpu_write(*p, 0);
>> -	}
>> -}
>> -
>>  /*
>>   * Determine the per node value of a stat item. This function
>>   * is called frequently in a NUMA machine, so try to be as
>> @@ -969,23 +873,6 @@ unsigned long sum_zone_node_page_state(int node,
>>  }
>>  
>>  /*
>> - * Determine the per node value of a numa stat item. To avoid deviation,
>> - * the per cpu stat number in vm_numa_stat_diff[] is also included.
>> - */
>> -unsigned long sum_zone_numa_state(int node,
>> -				 enum numa_stat_item item)
>> -{
>> -	struct zone *zones = NODE_DATA(node)->node_zones;
>> -	int i;
>> -	unsigned long count = 0;
>> -
>> -	for (i = 0; i < MAX_NR_ZONES; i++)
>> -		count += zone_numa_state_snapshot(zones + i, item);
>> -
>> -	return count;
>> -}
>> -
>> -/*
>>   * Determine the per node value of a stat item.
>>   */
>>  unsigned long node_page_state(struct pglist_data *pgdat,
>> @@ -1569,8 +1456,7 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
>>  		seq_printf(m, "\n  per-node stats");
>>  		for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) {
>>  			seq_printf(m, "\n      %-12s %lu",
>> -				vmstat_text[i + NR_VM_ZONE_STAT_ITEMS +
>> -				NR_VM_NUMA_STAT_ITEMS],
>> +				vmstat_text[i + NR_VM_ZONE_STAT_ITEMS],
>>  				node_page_state(pgdat, i));
>>  		}
>>  	}
>> @@ -1607,13 +1493,6 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
>>  		seq_printf(m, "\n      %-12s %lu", vmstat_text[i],
>>  				zone_page_state(zone, i));
>>  
>> -#ifdef CONFIG_NUMA
>> -	for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++)
>> -		seq_printf(m, "\n      %-12s %lu",
>> -				vmstat_text[i + NR_VM_ZONE_STAT_ITEMS],
>> -				zone_numa_state_snapshot(zone, i));
>> -#endif
>> -
>>  	seq_printf(m, "\n  pagesets");
>>  	for_each_online_cpu(i) {
>>  		struct per_cpu_pageset *pageset;
>> @@ -1688,7 +1567,6 @@ static void *vmstat_start(struct seq_file *m, loff_t *pos)
>>  	if (*pos >= ARRAY_SIZE(vmstat_text))
>>  		return NULL;
>>  	stat_items_size = NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long) +
>> -			  NR_VM_NUMA_STAT_ITEMS * sizeof(unsigned long) +
>>  			  NR_VM_NODE_STAT_ITEMS * sizeof(unsigned long) +
>>  			  NR_VM_WRITEBACK_STAT_ITEMS * sizeof(unsigned long);
>>  
>> @@ -1704,12 +1582,6 @@ static void *vmstat_start(struct seq_file *m, loff_t *pos)
>>  		v[i] = global_zone_page_state(i);
>>  	v += NR_VM_ZONE_STAT_ITEMS;
>>  
>> -#ifdef CONFIG_NUMA
>> -	for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++)
>> -		v[i] = global_numa_state(i);
>> -	v += NR_VM_NUMA_STAT_ITEMS;
>> -#endif
>> -
>>  	for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
>>  		v[i] = global_node_page_state(i);
>>  	v += NR_VM_NODE_STAT_ITEMS;
>> @@ -1811,16 +1683,6 @@ int vmstat_refresh(struct ctl_table *table, int write,
>>  			err = -EINVAL;
>>  		}
>>  	}
>> -#ifdef CONFIG_NUMA
>> -	for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++) {
>> -		val = atomic_long_read(&vm_numa_stat[i]);
>> -		if (val < 0) {
>> -			pr_warn("%s: %s %ld\n",
>> -				__func__, vmstat_text[i + NR_VM_ZONE_STAT_ITEMS], val);
>> -			err = -EINVAL;
>> -		}
>> -	}
>> -#endif
>>  	if (err)
>>  		return err;
>>  	if (write)
>> @@ -1862,9 +1724,6 @@ static bool need_update(int cpu)
>>  		struct per_cpu_pageset *p = per_cpu_ptr(zone->pageset, cpu);
>>  
>>  		BUILD_BUG_ON(sizeof(p->vm_stat_diff[0]) != 1);
>> -#ifdef CONFIG_NUMA
>> -		BUILD_BUG_ON(sizeof(p->vm_numa_stat_diff[0]) != 2);
>> -#endif
>>  
>>  		/*
>>  		 * The fast way of checking if there are any vmstat diffs.
>> @@ -1872,10 +1731,6 @@ static bool need_update(int cpu)
>>  		 */
>>  		if (memchr_inv(p->vm_stat_diff, 0, NR_VM_ZONE_STAT_ITEMS))
>>  			return true;
>> -#ifdef CONFIG_NUMA
>> -		if (memchr_inv(p->vm_numa_stat_diff, 0, NR_VM_NUMA_STAT_ITEMS))
>> -			return true;
>> -#endif
>>  	}
>>  	return false;
>>  }
>> -- 
>> 2.7.4
>>
>