@@ -341,20 +341,21 @@ struct per_cpu_pages {
int count; /* number of pages in the list */
int high; /* high watermark, emptying needed */
int batch; /* chunk size for buddy add/remove */
+#ifdef CONFIG_NUMA
+ int expire; /* When 0, remote pagesets are drained */
+#endif
/* Lists of pages, one per migrate type stored on the pcp-lists */
struct list_head lists[MIGRATE_PCPTYPES];
};
-struct per_cpu_pageset {
- struct per_cpu_pages pcp;
-#ifdef CONFIG_NUMA
- s8 expire;
- u16 vm_numa_stat_diff[NR_VM_NUMA_STAT_ITEMS];
-#endif
+struct per_cpu_zonestat {
#ifdef CONFIG_SMP
- s8 stat_threshold;
s8 vm_stat_diff[NR_VM_ZONE_STAT_ITEMS];
+ s8 stat_threshold;
+#endif
+#ifdef CONFIG_NUMA
+ u16 vm_numa_stat_diff[NR_VM_NUMA_STAT_ITEMS];
#endif
};
@@ -470,7 +471,8 @@ struct zone {
int node;
#endif
struct pglist_data *zone_pgdat;
- struct per_cpu_pageset __percpu *pageset;
+ struct per_cpu_pages __percpu *per_cpu_pageset;
+ struct per_cpu_zonestat __percpu *per_cpu_zonestats;
/*
* the high and batch values are copied to individual pagesets for
* faster access
@@ -163,7 +163,7 @@ static inline unsigned long zone_numa_state_snapshot(struct zone *zone,
int cpu;
for_each_online_cpu(cpu)
- x += per_cpu_ptr(zone->pageset, cpu)->vm_numa_stat_diff[item];
+ x += per_cpu_ptr(zone->per_cpu_zonestats, cpu)->vm_numa_stat_diff[item];
return x;
}
@@ -236,7 +236,7 @@ static inline unsigned long zone_page_state_snapshot(struct zone *zone,
#ifdef CONFIG_SMP
int cpu;
for_each_online_cpu(cpu)
- x += per_cpu_ptr(zone->pageset, cpu)->vm_stat_diff[item];
+ x += per_cpu_ptr(zone->per_cpu_zonestats, cpu)->vm_stat_diff[item];
if (x < 0)
x = 0;
@@ -291,7 +291,7 @@ struct ctl_table;
int vmstat_refresh(struct ctl_table *, int write, void *buffer, size_t *lenp,
loff_t *ppos);
-void drain_zonestat(struct zone *zone, struct per_cpu_pageset *);
+void drain_zonestat(struct zone *zone, struct per_cpu_zonestat *);
int calculate_pressure_threshold(struct zone *zone);
int calculate_normal_threshold(struct zone *zone);
@@ -399,7 +399,7 @@ static inline void cpu_vm_stats_fold(int cpu) { }
static inline void quiet_vmstat(void) { }
static inline void drain_zonestat(struct zone *zone,
- struct per_cpu_pageset *pset) { }
+ struct per_cpu_zonestat *pzstats) { }
#endif /* CONFIG_SMP */
static inline void __mod_zone_freepage_state(struct zone *zone, int nr_pages,
@@ -2981,15 +2981,14 @@ void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp)
static void drain_pages_zone(unsigned int cpu, struct zone *zone)
{
unsigned long flags;
- struct per_cpu_pageset *pset;
struct per_cpu_pages *pcp;
local_irq_save(flags);
- pset = per_cpu_ptr(zone->pageset, cpu);
- pcp = &pset->pcp;
+ pcp = per_cpu_ptr(zone->per_cpu_pageset, cpu);
if (pcp->count)
free_pcppages_bulk(zone, pcp->count, pcp);
+
local_irq_restore(flags);
}
@@ -3088,7 +3087,7 @@ static void __drain_all_pages(struct zone *zone, bool force_all_cpus)
* disables preemption as part of its processing
*/
for_each_online_cpu(cpu) {
- struct per_cpu_pageset *pcp;
+ struct per_cpu_pages *pcp;
struct zone *z;
bool has_pcps = false;
@@ -3099,13 +3098,13 @@ static void __drain_all_pages(struct zone *zone, bool force_all_cpus)
*/
has_pcps = true;
} else if (zone) {
- pcp = per_cpu_ptr(zone->pageset, cpu);
- if (pcp->pcp.count)
+ pcp = per_cpu_ptr(zone->per_cpu_pageset, cpu);
+ if (pcp->count)
has_pcps = true;
} else {
for_each_populated_zone(z) {
- pcp = per_cpu_ptr(z->pageset, cpu);
- if (pcp->pcp.count) {
+ pcp = per_cpu_ptr(z->per_cpu_pageset, cpu);
+ if (pcp->count) {
has_pcps = true;
break;
}
@@ -3235,7 +3234,7 @@ static void free_unref_page_commit(struct page *page, unsigned long pfn)
migratetype = MIGRATE_MOVABLE;
}
- pcp = &this_cpu_ptr(zone->pageset)->pcp;
+ pcp = this_cpu_ptr(zone->per_cpu_pageset);
list_add(&page->lru, &pcp->lists[migratetype]);
pcp->count++;
if (pcp->count >= READ_ONCE(pcp->high))
@@ -3451,7 +3450,7 @@ static struct page *rmqueue_pcplist(struct zone *preferred_zone,
unsigned long flags;
local_irq_save(flags);
- pcp = &this_cpu_ptr(zone->pageset)->pcp;
+ pcp = this_cpu_ptr(zone->per_cpu_pageset);
list = &pcp->lists[migratetype];
page = __rmqueue_pcplist(zone, migratetype, alloc_flags, pcp, list);
if (page) {
@@ -5054,7 +5053,7 @@ unsigned long __alloc_pages_bulk(gfp_t gfp, int preferred_nid,
/* Attempt the batch allocation */
local_irq_save(flags);
- pcp = &this_cpu_ptr(zone->pageset)->pcp;
+ pcp = this_cpu_ptr(zone->per_cpu_pageset);
pcp_list = &pcp->lists[ac.migratetype];
while (nr_populated < nr_pages) {
@@ -5667,7 +5666,7 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask)
continue;
for_each_online_cpu(cpu)
- free_pcp += per_cpu_ptr(zone->pageset, cpu)->pcp.count;
+ free_pcp += per_cpu_ptr(zone->per_cpu_pageset, cpu)->count;
}
printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n"
@@ -5759,7 +5758,7 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask)
free_pcp = 0;
for_each_online_cpu(cpu)
- free_pcp += per_cpu_ptr(zone->pageset, cpu)->pcp.count;
+ free_pcp += per_cpu_ptr(zone->per_cpu_pageset, cpu)->count;
show_node(zone);
printk(KERN_CONT
@@ -5800,7 +5799,7 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask)
K(zone_page_state(zone, NR_MLOCK)),
K(zone_page_state(zone, NR_BOUNCE)),
K(free_pcp),
- K(this_cpu_read(zone->pageset->pcp.count)),
+ K(this_cpu_read(zone->per_cpu_pageset->count)),
K(zone_page_state(zone, NR_FREE_CMA_PAGES)));
printk("lowmem_reserve[]:");
for (i = 0; i < MAX_NR_ZONES; i++)
@@ -6127,11 +6126,12 @@ static void build_zonelists(pg_data_t *pgdat)
* not check if the processor is online before following the pageset pointer.
* Other parts of the kernel may not check if the zone is available.
*/
-static void pageset_init(struct per_cpu_pageset *p);
+static void per_cpu_pages_init(struct per_cpu_pages *pcp, struct per_cpu_zonestat *pzstats);
/* These effectively disable the pcplists in the boot pageset completely */
#define BOOT_PAGESET_HIGH 0
#define BOOT_PAGESET_BATCH 1
-static DEFINE_PER_CPU(struct per_cpu_pageset, boot_pageset);
+static DEFINE_PER_CPU(struct per_cpu_pages, boot_pageset);
+static DEFINE_PER_CPU(struct per_cpu_zonestat, boot_zonestats);
static DEFINE_PER_CPU(struct per_cpu_nodestat, boot_nodestats);
static void __build_all_zonelists(void *data)
@@ -6198,7 +6198,7 @@ build_all_zonelists_init(void)
* (a chicken-egg dilemma).
*/
for_each_possible_cpu(cpu)
- pageset_init(&per_cpu(boot_pageset, cpu));
+ per_cpu_pages_init(&per_cpu(boot_pageset, cpu), &per_cpu(boot_zonestats, cpu));
mminit_verify_zonelist();
cpuset_init_current_mems_allowed();
@@ -6576,14 +6576,13 @@ static void pageset_update(struct per_cpu_pages *pcp, unsigned long high,
WRITE_ONCE(pcp->high, high);
}
-static void pageset_init(struct per_cpu_pageset *p)
+static void per_cpu_pages_init(struct per_cpu_pages *pcp, struct per_cpu_zonestat *pzstats)
{
- struct per_cpu_pages *pcp;
int migratetype;
- memset(p, 0, sizeof(*p));
+ memset(pcp, 0, sizeof(*pcp));
+ memset(pzstats, 0, sizeof(*pzstats));
- pcp = &p->pcp;
for (migratetype = 0; migratetype < MIGRATE_PCPTYPES; migratetype++)
INIT_LIST_HEAD(&pcp->lists[migratetype]);
@@ -6600,12 +6599,12 @@ static void pageset_init(struct per_cpu_pageset *p)
static void __zone_set_pageset_high_and_batch(struct zone *zone, unsigned long high,
unsigned long batch)
{
- struct per_cpu_pageset *p;
+ struct per_cpu_pages *pcp;
int cpu;
for_each_possible_cpu(cpu) {
- p = per_cpu_ptr(zone->pageset, cpu);
- pageset_update(&p->pcp, high, batch);
+ pcp = per_cpu_ptr(zone->per_cpu_pageset, cpu);
+ pageset_update(pcp, high, batch);
}
}
@@ -6640,13 +6639,20 @@ static void zone_set_pageset_high_and_batch(struct zone *zone)
void __meminit setup_zone_pageset(struct zone *zone)
{
- struct per_cpu_pageset *p;
int cpu;
- zone->pageset = alloc_percpu(struct per_cpu_pageset);
+ /* Size may be 0 on !SMP && !NUMA */
+ if (sizeof(struct per_cpu_zonestat) > 0)
+ zone->per_cpu_zonestats = alloc_percpu(struct per_cpu_zonestat);
+
+ zone->per_cpu_pageset = alloc_percpu(struct per_cpu_pages);
for_each_possible_cpu(cpu) {
- p = per_cpu_ptr(zone->pageset, cpu);
- pageset_init(p);
+ struct per_cpu_pages *pcp;
+ struct per_cpu_zonestat *pzstats;
+
+ pcp = per_cpu_ptr(zone->per_cpu_pageset, cpu);
+ pzstats = per_cpu_ptr(zone->per_cpu_zonestats, cpu);
+ per_cpu_pages_init(pcp, pzstats);
}
zone_set_pageset_high_and_batch(zone);
@@ -6673,9 +6679,9 @@ void __init setup_per_cpu_pageset(void)
* the nodes these zones are associated with.
*/
for_each_possible_cpu(cpu) {
- struct per_cpu_pageset *pcp = &per_cpu(boot_pageset, cpu);
- memset(pcp->vm_numa_stat_diff, 0,
- sizeof(pcp->vm_numa_stat_diff));
+ struct per_cpu_zonestat *pzstats = &per_cpu(boot_zonestats, cpu);
+ memset(pzstats->vm_numa_stat_diff, 0,
+ sizeof(pzstats->vm_numa_stat_diff));
}
#endif
@@ -6691,7 +6697,8 @@ static __meminit void zone_pcp_init(struct zone *zone)
* relies on the ability of the linker to provide the
* offset of a (static) per cpu variable into the per cpu area.
*/
- zone->pageset = &boot_pageset;
+ zone->per_cpu_pageset = &boot_pageset;
+ zone->per_cpu_zonestats = &boot_zonestats;
zone->pageset_high = BOOT_PAGESET_HIGH;
zone->pageset_batch = BOOT_PAGESET_BATCH;
@@ -8953,15 +8960,17 @@ void zone_pcp_enable(struct zone *zone)
void zone_pcp_reset(struct zone *zone)
{
int cpu;
- struct per_cpu_pageset *pset;
+ struct per_cpu_zonestat *pzstats;
- if (zone->pageset != &boot_pageset) {
+ if (zone->per_cpu_pageset != &boot_pageset) {
for_each_online_cpu(cpu) {
- pset = per_cpu_ptr(zone->pageset, cpu);
- drain_zonestat(zone, pset);
+ pzstats = per_cpu_ptr(zone->per_cpu_zonestats, cpu);
+ drain_zonestat(zone, pzstats);
}
- free_percpu(zone->pageset);
- zone->pageset = &boot_pageset;
+ free_percpu(zone->per_cpu_pageset);
+ free_percpu(zone->per_cpu_zonestats);
+ zone->per_cpu_pageset = &boot_pageset;
+ zone->per_cpu_zonestats = &boot_zonestats;
}
}
@@ -44,7 +44,7 @@ static void zero_zone_numa_counters(struct zone *zone)
for (item = 0; item < NR_VM_NUMA_STAT_ITEMS; item++) {
atomic_long_set(&zone->vm_numa_stat[item], 0);
for_each_online_cpu(cpu)
- per_cpu_ptr(zone->pageset, cpu)->vm_numa_stat_diff[item]
+ per_cpu_ptr(zone->per_cpu_zonestats, cpu)->vm_numa_stat_diff[item]
= 0;
}
}
@@ -266,7 +266,7 @@ void refresh_zone_stat_thresholds(void)
for_each_online_cpu(cpu) {
int pgdat_threshold;
- per_cpu_ptr(zone->pageset, cpu)->stat_threshold
+ per_cpu_ptr(zone->per_cpu_zonestats, cpu)->stat_threshold
= threshold;
/* Base nodestat threshold on the largest populated zone. */
@@ -303,7 +303,7 @@ void set_pgdat_percpu_threshold(pg_data_t *pgdat,
threshold = (*calculate_pressure)(zone);
for_each_online_cpu(cpu)
- per_cpu_ptr(zone->pageset, cpu)->stat_threshold
+ per_cpu_ptr(zone->per_cpu_zonestats, cpu)->stat_threshold
= threshold;
}
}
@@ -316,7 +316,7 @@ void set_pgdat_percpu_threshold(pg_data_t *pgdat,
void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
long delta)
{
- struct per_cpu_pageset __percpu *pcp = zone->pageset;
+ struct per_cpu_zonestat __percpu *pcp = zone->per_cpu_zonestats;
s8 __percpu *p = pcp->vm_stat_diff + item;
long x;
long t;
@@ -389,7 +389,7 @@ EXPORT_SYMBOL(__mod_node_page_state);
*/
void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
{
- struct per_cpu_pageset __percpu *pcp = zone->pageset;
+ struct per_cpu_zonestat __percpu *pcp = zone->per_cpu_zonestats;
s8 __percpu *p = pcp->vm_stat_diff + item;
s8 v, t;
@@ -435,7 +435,7 @@ EXPORT_SYMBOL(__inc_node_page_state);
void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
{
- struct per_cpu_pageset __percpu *pcp = zone->pageset;
+ struct per_cpu_zonestat __percpu *pcp = zone->per_cpu_zonestats;
s8 __percpu *p = pcp->vm_stat_diff + item;
s8 v, t;
@@ -495,7 +495,7 @@ EXPORT_SYMBOL(__dec_node_page_state);
static inline void mod_zone_state(struct zone *zone,
enum zone_stat_item item, long delta, int overstep_mode)
{
- struct per_cpu_pageset __percpu *pcp = zone->pageset;
+ struct per_cpu_zonestat __percpu *pcp = zone->per_cpu_zonestats;
s8 __percpu *p = pcp->vm_stat_diff + item;
long o, n, t, z;
@@ -781,19 +781,20 @@ static int refresh_cpu_vm_stats(bool do_pagesets)
int changes = 0;
for_each_populated_zone(zone) {
- struct per_cpu_pageset __percpu *p = zone->pageset;
+ struct per_cpu_zonestat __percpu *pzstats = zone->per_cpu_zonestats;
+ struct per_cpu_pages __percpu *pcp = zone->per_cpu_pageset;
for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) {
int v;
- v = this_cpu_xchg(p->vm_stat_diff[i], 0);
+ v = this_cpu_xchg(pzstats->vm_stat_diff[i], 0);
if (v) {
atomic_long_add(v, &zone->vm_stat[i]);
global_zone_diff[i] += v;
#ifdef CONFIG_NUMA
/* 3 seconds idle till flush */
- __this_cpu_write(p->expire, 3);
+ __this_cpu_write(pcp->expire, 3);
#endif
}
}
@@ -801,12 +802,12 @@ static int refresh_cpu_vm_stats(bool do_pagesets)
for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++) {
int v;
- v = this_cpu_xchg(p->vm_numa_stat_diff[i], 0);
+ v = this_cpu_xchg(pzstats->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);
+ __this_cpu_write(pcp->expire, 3);
}
}
@@ -819,23 +820,23 @@ static int refresh_cpu_vm_stats(bool do_pagesets)
* Check if there are pages remaining in this pageset
* if not then there is nothing to expire.
*/
- if (!__this_cpu_read(p->expire) ||
- !__this_cpu_read(p->pcp.count))
+ if (!__this_cpu_read(pcp->expire) ||
+ !__this_cpu_read(pcp->count))
continue;
/*
* We never drain zones local to this processor.
*/
if (zone_to_nid(zone) == numa_node_id()) {
- __this_cpu_write(p->expire, 0);
+ __this_cpu_write(pcp->expire, 0);
continue;
}
- if (__this_cpu_dec_return(p->expire))
+ if (__this_cpu_dec_return(pcp->expire))
continue;
- if (__this_cpu_read(p->pcp.count)) {
- drain_zone_pages(zone, this_cpu_ptr(&p->pcp));
+ if (__this_cpu_read(pcp->count)) {
+ drain_zone_pages(zone, this_cpu_ptr(pcp));
changes++;
}
}
@@ -882,27 +883,27 @@ void cpu_vm_stats_fold(int cpu)
int global_node_diff[NR_VM_NODE_STAT_ITEMS] = { 0, };
for_each_populated_zone(zone) {
- struct per_cpu_pageset *p;
+ struct per_cpu_zonestat *pzstats;
- p = per_cpu_ptr(zone->pageset, cpu);
+ pzstats = per_cpu_ptr(zone->per_cpu_zonestats, cpu);
for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
- if (p->vm_stat_diff[i]) {
+ if (pzstats->vm_stat_diff[i]) {
int v;
- v = p->vm_stat_diff[i];
- p->vm_stat_diff[i] = 0;
+ v = pzstats->vm_stat_diff[i];
+ pzstats->vm_stat_diff[i] = 0;
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]) {
+ if (pzstats->vm_numa_stat_diff[i]) {
int v;
- v = p->vm_numa_stat_diff[i];
- p->vm_numa_stat_diff[i] = 0;
+ v = pzstats->vm_numa_stat_diff[i];
+ pzstats->vm_numa_stat_diff[i] = 0;
atomic_long_add(v, &zone->vm_numa_stat[i]);
global_numa_diff[i] += v;
}
@@ -936,24 +937,24 @@ void cpu_vm_stats_fold(int cpu)
* this is only called if !populated_zone(zone), which implies no other users of
* pset->vm_stat_diff[] exsist.
*/
-void drain_zonestat(struct zone *zone, struct per_cpu_pageset *pset)
+void drain_zonestat(struct zone *zone, struct per_cpu_zonestat *pzstats)
{
int i;
for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
- if (pset->vm_stat_diff[i]) {
- int v = pset->vm_stat_diff[i];
- pset->vm_stat_diff[i] = 0;
+ if (pzstats->vm_stat_diff[i]) {
+ int v = pzstats->vm_stat_diff[i];
+ pzstats->vm_stat_diff[i] = 0;
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];
+ if (pzstats->vm_numa_stat_diff[i]) {
+ int v = pzstats->vm_numa_stat_diff[i];
- pset->vm_numa_stat_diff[i] = 0;
+ pzstats->vm_numa_stat_diff[i] = 0;
atomic_long_add(v, &zone->vm_numa_stat[i]);
atomic_long_add(v, &vm_numa_stat[i]);
}
@@ -965,8 +966,8 @@ void drain_zonestat(struct zone *zone, struct per_cpu_pageset *pset)
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;
+ struct per_cpu_zonestat __percpu *pzstats = zone->per_cpu_zonestats;
+ u16 __percpu *p = pzstats->vm_numa_stat_diff + item;
u16 v;
v = __this_cpu_inc_return(*p);
@@ -1685,21 +1686,23 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
seq_printf(m, "\n pagesets");
for_each_online_cpu(i) {
- struct per_cpu_pageset *pageset;
+ struct per_cpu_pages *pcp;
+ struct per_cpu_zonestat *pzstats;
- pageset = per_cpu_ptr(zone->pageset, i);
+ pcp = per_cpu_ptr(zone->per_cpu_pageset, i);
+ pzstats = per_cpu_ptr(zone->per_cpu_zonestats, i);
seq_printf(m,
"\n cpu: %i"
"\n count: %i"
"\n high: %i"
"\n batch: %i",
i,
- pageset->pcp.count,
- pageset->pcp.high,
- pageset->pcp.batch);
+ pcp->count,
+ pcp->high,
+ pcp->batch);
#ifdef CONFIG_SMP
seq_printf(m, "\n vm stats threshold: %d",
- pageset->stat_threshold);
+ pzstats->stat_threshold);
#endif
}
seq_printf(m,
@@ -1910,17 +1913,18 @@ static bool need_update(int cpu)
struct zone *zone;
for_each_populated_zone(zone) {
- struct per_cpu_pageset *p = per_cpu_ptr(zone->pageset, cpu);
+ struct per_cpu_zonestat *pzstats = per_cpu_ptr(zone->per_cpu_zonestats, cpu);
struct per_cpu_nodestat *n;
+
/*
* The fast way of checking if there are any vmstat diffs.
*/
- if (memchr_inv(p->vm_stat_diff, 0, NR_VM_ZONE_STAT_ITEMS *
- sizeof(p->vm_stat_diff[0])))
+ if (memchr_inv(pzstats->vm_stat_diff, 0, NR_VM_ZONE_STAT_ITEMS *
+ sizeof(pzstats->vm_stat_diff[0])))
return true;
#ifdef CONFIG_NUMA
- if (memchr_inv(p->vm_numa_stat_diff, 0, NR_VM_NUMA_STAT_ITEMS *
- sizeof(p->vm_numa_stat_diff[0])))
+ if (memchr_inv(pzstats->vm_numa_stat_diff, 0, NR_VM_NUMA_STAT_ITEMS *
+ sizeof(pzstats->vm_numa_stat_diff[0])))
return true;
#endif
if (last_pgdat == zone->zone_pgdat)
The per-cpu page allocator lists and the per-cpu vmstat deltas are stored in the same struct per_cpu_pages even though vmstats have no direct impact on the per-cpu page lists. This is inconsistent because the vmstats for a node are stored on a dedicated structure. The bigger issue is that the per_cpu_pages structure is not cache-aligned and stat updates either cache conflict with adjacent per-cpu lists incurring a runtime cost or padding is required incurring a memory cost. This patch splits the per-cpu pagelists and the vmstat deltas into separate structures. It's mostly a mechanical conversion but some variable renaming is done to clearly distinguish the per-cpu pages structure (pcp) from the vmstats (pzstats). Superficially, this appears to increase the size of the per_cpu_pages structure but the movement of expire fills a structure hole so there is no impact overall. [lkp@intel.com: Check struct per_cpu_zonestat has a non-zero size] [vbabka@suse.cz: Init zone->per_cpu_zonestats properly] Signed-off-by: Mel Gorman <mgorman@techsingularity.net> --- include/linux/mmzone.h | 18 ++++---- include/linux/vmstat.h | 8 ++-- mm/page_alloc.c | 85 ++++++++++++++++++++----------------- mm/vmstat.c | 96 ++++++++++++++++++++++-------------------- 4 files changed, 111 insertions(+), 96 deletions(-)