#include <linux/mm.h>
#include <linux/err.h>
#include <linux/module.h>
+#include <linux/slab.h>
#include <linux/cpu.h>
#include <linux/vmstat.h>
#include <linux/sched.h>
+#include <linux/math64.h>
+#include <linux/writeback.h>
+#include <linux/compaction.h>
#ifdef CONFIG_VM_EVENT_COUNTERS
DEFINE_PER_CPU(struct vm_event_state, vm_event_states) = {{0}};
EXPORT_PER_CPU_SYMBOL(vm_event_states);
-static void sum_vm_events(unsigned long *ret, const struct cpumask *cpumask)
+static void sum_vm_events(unsigned long *ret)
{
int cpu;
int i;
memset(ret, 0, NR_VM_EVENT_ITEMS * sizeof(unsigned long));
- for_each_cpu_mask_nr(cpu, *cpumask) {
+ for_each_online_cpu(cpu) {
struct vm_event_state *this = &per_cpu(vm_event_states, cpu);
for (i = 0; i < NR_VM_EVENT_ITEMS; i++)
void all_vm_events(unsigned long *ret)
{
get_online_cpus();
- sum_vm_events(ret, cpu_online_mask);
+ sum_vm_events(ret);
put_online_cpus();
}
EXPORT_SYMBOL_GPL(all_vm_events);
#ifdef CONFIG_SMP
-static int calculate_threshold(struct zone *zone)
+int calculate_pressure_threshold(struct zone *zone)
+{
+ int threshold;
+ int watermark_distance;
+
+ /*
+ * As vmstats are not up to date, there is drift between the estimated
+ * and real values. For high thresholds and a high number of CPUs, it
+ * is possible for the min watermark to be breached while the estimated
+ * value looks fine. The pressure threshold is a reduced value such
+ * that even the maximum amount of drift will not accidentally breach
+ * the min watermark
+ */
+ watermark_distance = low_wmark_pages(zone) - min_wmark_pages(zone);
+ threshold = max(1, (int)(watermark_distance / num_online_cpus()));
+
+ /*
+ * Maximum threshold is 125
+ */
+ threshold = min(125, threshold);
+
+ return threshold;
+}
+
+int calculate_normal_threshold(struct zone *zone)
{
int threshold;
int mem; /* memory in 128 MB units */
/*
* Refresh the thresholds for each zone.
*/
-static void refresh_zone_stat_thresholds(void)
+void refresh_zone_stat_thresholds(void)
{
struct zone *zone;
int cpu;
int threshold;
- for_each_zone(zone) {
+ for_each_populated_zone(zone) {
+ unsigned long max_drift, tolerate_drift;
- if (!zone->present_pages)
- continue;
-
- threshold = calculate_threshold(zone);
+ threshold = calculate_normal_threshold(zone);
for_each_online_cpu(cpu)
- zone_pcp(zone, cpu)->stat_threshold = threshold;
+ per_cpu_ptr(zone->pageset, cpu)->stat_threshold
+ = threshold;
+
+ /*
+ * Only set percpu_drift_mark if there is a danger that
+ * NR_FREE_PAGES reports the low watermark is ok when in fact
+ * the min watermark could be breached by an allocation
+ */
+ tolerate_drift = low_wmark_pages(zone) - min_wmark_pages(zone);
+ max_drift = num_online_cpus() * threshold;
+ if (max_drift > tolerate_drift)
+ zone->percpu_drift_mark = high_wmark_pages(zone) +
+ max_drift;
+ }
+}
+
+void set_pgdat_percpu_threshold(pg_data_t *pgdat,
+ int (*calculate_pressure)(struct zone *))
+{
+ struct zone *zone;
+ int cpu;
+ int threshold;
+ int i;
+
+ for (i = 0; i < pgdat->nr_zones; i++) {
+ zone = &pgdat->node_zones[i];
+ if (!zone->percpu_drift_mark)
+ continue;
+
+ threshold = (*calculate_pressure)(zone);
+ for_each_possible_cpu(cpu)
+ per_cpu_ptr(zone->pageset, cpu)->stat_threshold
+ = threshold;
}
}
void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
int delta)
{
- struct per_cpu_pageset *pcp = zone_pcp(zone, smp_processor_id());
- s8 *p = pcp->vm_stat_diff + item;
+ struct per_cpu_pageset __percpu *pcp = zone->pageset;
+ s8 __percpu *p = pcp->vm_stat_diff + item;
long x;
+ long t;
- x = delta + *p;
+ x = delta + __this_cpu_read(*p);
- if (unlikely(x > pcp->stat_threshold || x < -pcp->stat_threshold)) {
+ t = __this_cpu_read(pcp->stat_threshold);
+
+ if (unlikely(x > t || x < -t)) {
zone_page_state_add(x, zone, item);
x = 0;
}
- *p = x;
+ __this_cpu_write(*p, x);
}
EXPORT_SYMBOL(__mod_zone_page_state);
-/*
- * For an unknown interrupt state
- */
-void mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
- int delta)
-{
- unsigned long flags;
-
- local_irq_save(flags);
- __mod_zone_page_state(zone, item, delta);
- local_irq_restore(flags);
-}
-EXPORT_SYMBOL(mod_zone_page_state);
-
/*
* Optimized increment and decrement functions.
*
*/
void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
{
- struct per_cpu_pageset *pcp = zone_pcp(zone, smp_processor_id());
- s8 *p = pcp->vm_stat_diff + item;
+ struct per_cpu_pageset __percpu *pcp = zone->pageset;
+ s8 __percpu *p = pcp->vm_stat_diff + item;
+ s8 v, t;
- (*p)++;
+ v = __this_cpu_inc_return(*p);
+ t = __this_cpu_read(pcp->stat_threshold);
+ if (unlikely(v > t)) {
+ s8 overstep = t >> 1;
- if (unlikely(*p > pcp->stat_threshold)) {
- int overstep = pcp->stat_threshold / 2;
-
- zone_page_state_add(*p + overstep, zone, item);
- *p = -overstep;
+ zone_page_state_add(v + overstep, zone, item);
+ __this_cpu_write(*p, -overstep);
}
}
void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
{
- struct per_cpu_pageset *pcp = zone_pcp(zone, smp_processor_id());
- s8 *p = pcp->vm_stat_diff + item;
-
- (*p)--;
+ struct per_cpu_pageset __percpu *pcp = zone->pageset;
+ s8 __percpu *p = pcp->vm_stat_diff + item;
+ s8 v, t;
- if (unlikely(*p < - pcp->stat_threshold)) {
- int overstep = pcp->stat_threshold / 2;
+ v = __this_cpu_dec_return(*p);
+ t = __this_cpu_read(pcp->stat_threshold);
+ if (unlikely(v < - t)) {
+ s8 overstep = t >> 1;
- zone_page_state_add(*p - overstep, zone, item);
- *p = overstep;
+ zone_page_state_add(v - overstep, zone, item);
+ __this_cpu_write(*p, overstep);
}
}
}
EXPORT_SYMBOL(__dec_zone_page_state);
+#ifdef CONFIG_CMPXCHG_LOCAL
+/*
+ * If we have cmpxchg_local support then we do not need to incur the overhead
+ * that comes with local_irq_save/restore if we use this_cpu_cmpxchg.
+ *
+ * mod_state() modifies the zone counter state through atomic per cpu
+ * operations.
+ *
+ * Overstep mode specifies how overstep should handled:
+ * 0 No overstepping
+ * 1 Overstepping half of threshold
+ * -1 Overstepping minus half of threshold
+*/
+static inline void mod_state(struct zone *zone,
+ enum zone_stat_item item, int delta, int overstep_mode)
+{
+ struct per_cpu_pageset __percpu *pcp = zone->pageset;
+ s8 __percpu *p = pcp->vm_stat_diff + item;
+ long o, n, t, z;
+
+ do {
+ z = 0; /* overflow to zone counters */
+
+ /*
+ * The fetching of the stat_threshold is racy. We may apply
+ * a counter threshold to the wrong the cpu if we get
+ * rescheduled while executing here. However, the next
+ * counter update will apply the threshold again and
+ * therefore bring the counter under the threshold again.
+ *
+ * Most of the time the thresholds are the same anyways
+ * for all cpus in a zone.
+ */
+ t = this_cpu_read(pcp->stat_threshold);
+
+ o = this_cpu_read(*p);
+ n = delta + o;
+
+ if (n > t || n < -t) {
+ int os = overstep_mode * (t >> 1) ;
+
+ /* Overflow must be added to zone counters */
+ z = n + os;
+ n = -os;
+ }
+ } while (this_cpu_cmpxchg(*p, o, n) != o);
+
+ if (z)
+ zone_page_state_add(z, zone, item);
+}
+
+void mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
+ int delta)
+{
+ mod_state(zone, item, delta, 0);
+}
+EXPORT_SYMBOL(mod_zone_page_state);
+
+void inc_zone_state(struct zone *zone, enum zone_stat_item item)
+{
+ mod_state(zone, item, 1, 1);
+}
+
+void inc_zone_page_state(struct page *page, enum zone_stat_item item)
+{
+ mod_state(page_zone(page), item, 1, 1);
+}
+EXPORT_SYMBOL(inc_zone_page_state);
+
+void dec_zone_page_state(struct page *page, enum zone_stat_item item)
+{
+ mod_state(page_zone(page), item, -1, -1);
+}
+EXPORT_SYMBOL(dec_zone_page_state);
+#else
+/*
+ * Use interrupt disable to serialize counter updates
+ */
+void mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
+ int delta)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ __mod_zone_page_state(zone, item, delta);
+ local_irq_restore(flags);
+}
+EXPORT_SYMBOL(mod_zone_page_state);
+
void inc_zone_state(struct zone *zone, enum zone_stat_item item)
{
unsigned long flags;
local_irq_restore(flags);
}
EXPORT_SYMBOL(dec_zone_page_state);
+#endif
/*
* Update the zone counters for one cpu.
int i;
int global_diff[NR_VM_ZONE_STAT_ITEMS] = { 0, };
- for_each_zone(zone) {
+ for_each_populated_zone(zone) {
struct per_cpu_pageset *p;
- if (!populated_zone(zone))
- continue;
-
- p = zone_pcp(zone, cpu);
+ p = per_cpu_ptr(zone->pageset, cpu);
for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
if (p->vm_stat_diff[i]) {
* z = the zone from which the allocation occurred.
*
* Must be called with interrupts disabled.
+ *
+ * When __GFP_OTHER_NODE is set assume the node of the preferred
+ * zone is the local node. This is useful for daemons who allocate
+ * memory on behalf of other processes.
*/
-void zone_statistics(struct zone *preferred_zone, struct zone *z)
+void zone_statistics(struct zone *preferred_zone, struct zone *z, gfp_t flags)
{
if (z->zone_pgdat == preferred_zone->zone_pgdat) {
__inc_zone_state(z, NUMA_HIT);
__inc_zone_state(z, NUMA_MISS);
__inc_zone_state(preferred_zone, NUMA_FOREIGN);
}
- if (z->node == numa_node_id())
+ if (z->node == ((flags & __GFP_OTHER_NODE) ?
+ preferred_zone->node : numa_node_id()))
__inc_zone_state(z, NUMA_LOCAL);
else
__inc_zone_state(z, NUMA_OTHER);
}
#endif
-#ifdef CONFIG_PROC_FS
+#ifdef CONFIG_COMPACTION
+
+struct contig_page_info {
+ unsigned long free_pages;
+ unsigned long free_blocks_total;
+ unsigned long free_blocks_suitable;
+};
+
+/*
+ * Calculate the number of free pages in a zone, how many contiguous
+ * pages are free and how many are large enough to satisfy an allocation of
+ * the target size. Note that this function makes no attempt to estimate
+ * how many suitable free blocks there *might* be if MOVABLE pages were
+ * migrated. Calculating that is possible, but expensive and can be
+ * figured out from userspace
+ */
+static void fill_contig_page_info(struct zone *zone,
+ unsigned int suitable_order,
+ struct contig_page_info *info)
+{
+ unsigned int order;
+
+ info->free_pages = 0;
+ info->free_blocks_total = 0;
+ info->free_blocks_suitable = 0;
+
+ for (order = 0; order < MAX_ORDER; order++) {
+ unsigned long blocks;
+
+ /* Count number of free blocks */
+ blocks = zone->free_area[order].nr_free;
+ info->free_blocks_total += blocks;
+
+ /* Count free base pages */
+ info->free_pages += blocks << order;
+
+ /* Count the suitable free blocks */
+ if (order >= suitable_order)
+ info->free_blocks_suitable += blocks <<
+ (order - suitable_order);
+ }
+}
+
+/*
+ * A fragmentation index only makes sense if an allocation of a requested
+ * size would fail. If that is true, the fragmentation index indicates
+ * whether external fragmentation or a lack of memory was the problem.
+ * The value can be used to determine if page reclaim or compaction
+ * should be used
+ */
+static int __fragmentation_index(unsigned int order, struct contig_page_info *info)
+{
+ unsigned long requested = 1UL << order;
+
+ if (!info->free_blocks_total)
+ return 0;
+
+ /* Fragmentation index only makes sense when a request would fail */
+ if (info->free_blocks_suitable)
+ return -1000;
+
+ /*
+ * Index is between 0 and 1 so return within 3 decimal places
+ *
+ * 0 => allocation would fail due to lack of memory
+ * 1 => allocation would fail due to fragmentation
+ */
+ return 1000 - div_u64( (1000+(div_u64(info->free_pages * 1000ULL, requested))), info->free_blocks_total);
+}
+
+/* Same as __fragmentation index but allocs contig_page_info on stack */
+int fragmentation_index(struct zone *zone, unsigned int order)
+{
+ struct contig_page_info info;
+
+ fill_contig_page_info(zone, order, &info);
+ return __fragmentation_index(order, &info);
+}
+#endif
+
+#if defined(CONFIG_PROC_FS) || defined(CONFIG_COMPACTION)
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
spin_unlock_irqrestore(&zone->lock, flags);
}
}
+#endif
+
+#if defined(CONFIG_PROC_FS) || defined(CONFIG_SYSFS)
+#ifdef CONFIG_ZONE_DMA
+#define TEXT_FOR_DMA(xx) xx "_dma",
+#else
+#define TEXT_FOR_DMA(xx)
+#endif
+
+#ifdef CONFIG_ZONE_DMA32
+#define TEXT_FOR_DMA32(xx) xx "_dma32",
+#else
+#define TEXT_FOR_DMA32(xx)
+#endif
+
+#ifdef CONFIG_HIGHMEM
+#define TEXT_FOR_HIGHMEM(xx) xx "_high",
+#else
+#define TEXT_FOR_HIGHMEM(xx)
+#endif
+
+#define TEXTS_FOR_ZONES(xx) TEXT_FOR_DMA(xx) TEXT_FOR_DMA32(xx) xx "_normal", \
+ TEXT_FOR_HIGHMEM(xx) xx "_movable",
+
+const char * const vmstat_text[] = {
+ /* Zoned VM counters */
+ "nr_free_pages",
+ "nr_inactive_anon",
+ "nr_active_anon",
+ "nr_inactive_file",
+ "nr_active_file",
+ "nr_unevictable",
+ "nr_mlock",
+ "nr_anon_pages",
+ "nr_mapped",
+ "nr_file_pages",
+ "nr_dirty",
+ "nr_writeback",
+ "nr_slab_reclaimable",
+ "nr_slab_unreclaimable",
+ "nr_page_table_pages",
+ "nr_kernel_stack",
+ "nr_unstable",
+ "nr_bounce",
+ "nr_vmscan_write",
+ "nr_writeback_temp",
+ "nr_isolated_anon",
+ "nr_isolated_file",
+ "nr_shmem",
+ "nr_dirtied",
+ "nr_written",
+
+#ifdef CONFIG_NUMA
+ "numa_hit",
+ "numa_miss",
+ "numa_foreign",
+ "numa_interleave",
+ "numa_local",
+ "numa_other",
+#endif
+ "nr_anon_transparent_hugepages",
+ "nr_dirty_threshold",
+ "nr_dirty_background_threshold",
+
+#ifdef CONFIG_VM_EVENT_COUNTERS
+ "pgpgin",
+ "pgpgout",
+ "pswpin",
+ "pswpout",
+
+ TEXTS_FOR_ZONES("pgalloc")
+
+ "pgfree",
+ "pgactivate",
+ "pgdeactivate",
+ "pgfault",
+ "pgmajfault",
+
+ TEXTS_FOR_ZONES("pgrefill")
+ TEXTS_FOR_ZONES("pgsteal")
+ TEXTS_FOR_ZONES("pgscan_kswapd")
+ TEXTS_FOR_ZONES("pgscan_direct")
+
+#ifdef CONFIG_NUMA
+ "zone_reclaim_failed",
+#endif
+ "pginodesteal",
+ "slabs_scanned",
+ "kswapd_steal",
+ "kswapd_inodesteal",
+ "kswapd_low_wmark_hit_quickly",
+ "kswapd_high_wmark_hit_quickly",
+ "kswapd_skip_congestion_wait",
+ "pageoutrun",
+ "allocstall",
+
+ "pgrotated",
+
+#ifdef CONFIG_COMPACTION
+ "compact_blocks_moved",
+ "compact_pages_moved",
+ "compact_pagemigrate_failed",
+ "compact_stall",
+ "compact_fail",
+ "compact_success",
+#endif
+
+#ifdef CONFIG_HUGETLB_PAGE
+ "htlb_buddy_alloc_success",
+ "htlb_buddy_alloc_fail",
+#endif
+ "unevictable_pgs_culled",
+ "unevictable_pgs_scanned",
+ "unevictable_pgs_rescued",
+ "unevictable_pgs_mlocked",
+ "unevictable_pgs_munlocked",
+ "unevictable_pgs_cleared",
+ "unevictable_pgs_stranded",
+ "unevictable_pgs_mlockfreed",
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+ "thp_fault_alloc",
+ "thp_fault_fallback",
+ "thp_collapse_alloc",
+ "thp_collapse_alloc_failed",
+ "thp_split",
+#endif
+
+#endif /* CONFIG_VM_EVENTS_COUNTERS */
+};
+#endif /* CONFIG_PROC_FS || CONFIG_SYSFS */
+
+
+#ifdef CONFIG_PROC_FS
static void frag_show_print(struct seq_file *m, pg_data_t *pgdat,
struct zone *zone)
{
continue;
page = pfn_to_page(pfn);
-#ifdef CONFIG_ARCH_FLATMEM_HAS_HOLES
- /*
- * Ordinarily, memory holes in flatmem still have a valid
- * memmap for the PFN range. However, an architecture for
- * embedded systems (e.g. ARM) can free up the memmap backing
- * holes to save memory on the assumption the memmap is
- * never used. The page_zone linkages are then broken even
- * though pfn_valid() returns true. Skip the page if the
- * linkages are broken. Even if this test passed, the impact
- * is that the counters for the movable type are off but
- * fragmentation monitoring is likely meaningless on small
- * systems.
- */
- if (page_zone(page) != zone)
+
+ /* Watch for unexpected holes punched in the memmap */
+ if (!memmap_valid_within(pfn, page, zone))
continue;
-#endif
+
mtype = get_pageblock_migratetype(page);
if (mtype < MIGRATE_TYPES)
.release = seq_release,
};
-#ifdef CONFIG_ZONE_DMA
-#define TEXT_FOR_DMA(xx) xx "_dma",
-#else
-#define TEXT_FOR_DMA(xx)
-#endif
-
-#ifdef CONFIG_ZONE_DMA32
-#define TEXT_FOR_DMA32(xx) xx "_dma32",
-#else
-#define TEXT_FOR_DMA32(xx)
-#endif
-
-#ifdef CONFIG_HIGHMEM
-#define TEXT_FOR_HIGHMEM(xx) xx "_high",
-#else
-#define TEXT_FOR_HIGHMEM(xx)
-#endif
-
-#define TEXTS_FOR_ZONES(xx) TEXT_FOR_DMA(xx) TEXT_FOR_DMA32(xx) xx "_normal", \
- TEXT_FOR_HIGHMEM(xx) xx "_movable",
-
-static const char * const vmstat_text[] = {
- /* Zoned VM counters */
- "nr_free_pages",
- "nr_inactive_anon",
- "nr_active_anon",
- "nr_inactive_file",
- "nr_active_file",
-#ifdef CONFIG_UNEVICTABLE_LRU
- "nr_unevictable",
- "nr_mlock",
-#endif
- "nr_anon_pages",
- "nr_mapped",
- "nr_file_pages",
- "nr_dirty",
- "nr_writeback",
- "nr_slab_reclaimable",
- "nr_slab_unreclaimable",
- "nr_page_table_pages",
- "nr_unstable",
- "nr_bounce",
- "nr_vmscan_write",
- "nr_writeback_temp",
-
-#ifdef CONFIG_NUMA
- "numa_hit",
- "numa_miss",
- "numa_foreign",
- "numa_interleave",
- "numa_local",
- "numa_other",
-#endif
-
-#ifdef CONFIG_VM_EVENT_COUNTERS
- "pgpgin",
- "pgpgout",
- "pswpin",
- "pswpout",
-
- TEXTS_FOR_ZONES("pgalloc")
-
- "pgfree",
- "pgactivate",
- "pgdeactivate",
-
- "pgfault",
- "pgmajfault",
-
- TEXTS_FOR_ZONES("pgrefill")
- TEXTS_FOR_ZONES("pgsteal")
- TEXTS_FOR_ZONES("pgscan_kswapd")
- TEXTS_FOR_ZONES("pgscan_direct")
-
- "pginodesteal",
- "slabs_scanned",
- "kswapd_steal",
- "kswapd_inodesteal",
- "pageoutrun",
- "allocstall",
-
- "pgrotated",
-#ifdef CONFIG_HUGETLB_PAGE
- "htlb_buddy_alloc_success",
- "htlb_buddy_alloc_fail",
-#endif
-#ifdef CONFIG_UNEVICTABLE_LRU
- "unevictable_pgs_culled",
- "unevictable_pgs_scanned",
- "unevictable_pgs_rescued",
- "unevictable_pgs_mlocked",
- "unevictable_pgs_munlocked",
- "unevictable_pgs_cleared",
- "unevictable_pgs_stranded",
- "unevictable_pgs_mlockfreed",
-#endif
-#endif
-};
-
static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
struct zone *zone)
{
"\n min %lu"
"\n low %lu"
"\n high %lu"
- "\n scanned %lu (aa: %lu ia: %lu af: %lu if: %lu)"
+ "\n scanned %lu"
"\n spanned %lu"
"\n present %lu",
zone_page_state(zone, NR_FREE_PAGES),
- zone->pages_min,
- zone->pages_low,
- zone->pages_high,
+ min_wmark_pages(zone),
+ low_wmark_pages(zone),
+ high_wmark_pages(zone),
zone->pages_scanned,
- zone->lru[LRU_ACTIVE_ANON].nr_scan,
- zone->lru[LRU_INACTIVE_ANON].nr_scan,
- zone->lru[LRU_ACTIVE_FILE].nr_scan,
- zone->lru[LRU_INACTIVE_FILE].nr_scan,
zone->spanned_pages,
zone->present_pages);
for_each_online_cpu(i) {
struct per_cpu_pageset *pageset;
- pageset = zone_pcp(zone, i);
+ pageset = per_cpu_ptr(zone->pageset, i);
seq_printf(m,
"\n cpu: %i"
"\n count: %i"
}
seq_printf(m,
"\n all_unreclaimable: %u"
- "\n prev_priority: %i"
"\n start_pfn: %lu"
"\n inactive_ratio: %u",
- zone_is_all_unreclaimable(zone),
- zone->prev_priority,
+ zone->all_unreclaimable,
zone->zone_start_pfn,
zone->inactive_ratio);
seq_putc(m, '\n');
.release = seq_release,
};
+enum writeback_stat_item {
+ NR_DIRTY_THRESHOLD,
+ NR_DIRTY_BG_THRESHOLD,
+ NR_VM_WRITEBACK_STAT_ITEMS,
+};
+
static void *vmstat_start(struct seq_file *m, loff_t *pos)
{
unsigned long *v;
-#ifdef CONFIG_VM_EVENT_COUNTERS
- unsigned long *e;
-#endif
- int i;
+ int i, stat_items_size;
if (*pos >= ARRAY_SIZE(vmstat_text))
return NULL;
+ stat_items_size = NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long) +
+ NR_VM_WRITEBACK_STAT_ITEMS * sizeof(unsigned long);
#ifdef CONFIG_VM_EVENT_COUNTERS
- v = kmalloc(NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long)
- + sizeof(struct vm_event_state), GFP_KERNEL);
-#else
- v = kmalloc(NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long),
- GFP_KERNEL);
+ stat_items_size += sizeof(struct vm_event_state);
#endif
+
+ v = kmalloc(stat_items_size, GFP_KERNEL);
m->private = v;
if (!v)
return ERR_PTR(-ENOMEM);
for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
v[i] = global_page_state(i);
+ v += NR_VM_ZONE_STAT_ITEMS;
+
+ global_dirty_limits(v + NR_DIRTY_BG_THRESHOLD,
+ v + NR_DIRTY_THRESHOLD);
+ v += NR_VM_WRITEBACK_STAT_ITEMS;
+
#ifdef CONFIG_VM_EVENT_COUNTERS
- e = v + NR_VM_ZONE_STAT_ITEMS;
- all_vm_events(e);
- e[PGPGIN] /= 2; /* sectors -> kbytes */
- e[PGPGOUT] /= 2;
+ all_vm_events(v);
+ v[PGPGIN] /= 2; /* sectors -> kbytes */
+ v[PGPGOUT] /= 2;
#endif
- return v + *pos;
+ return (unsigned long *)m->private + *pos;
}
static void *vmstat_next(struct seq_file *m, void *arg, loff_t *pos)
{
refresh_cpu_vm_stats(smp_processor_id());
schedule_delayed_work(&__get_cpu_var(vmstat_work),
- sysctl_stat_interval);
+ round_jiffies_relative(sysctl_stat_interval));
}
static void __cpuinit start_cpu_timer(int cpu)
{
- struct delayed_work *vmstat_work = &per_cpu(vmstat_work, cpu);
+ struct delayed_work *work = &per_cpu(vmstat_work, cpu);
- INIT_DELAYED_WORK_DEFERRABLE(vmstat_work, vmstat_update);
- schedule_delayed_work_on(cpu, vmstat_work, HZ + cpu);
+ INIT_DELAYED_WORK_DEFERRABLE(work, vmstat_update);
+ schedule_delayed_work_on(cpu, work, __round_jiffies_relative(HZ, cpu));
}
/*
switch (action) {
case CPU_ONLINE:
case CPU_ONLINE_FROZEN:
+ refresh_zone_stat_thresholds();
start_cpu_timer(cpu);
+ node_set_state(cpu_to_node(cpu), N_CPU);
break;
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
- cancel_rearming_delayed_work(&per_cpu(vmstat_work, cpu));
+ cancel_delayed_work_sync(&per_cpu(vmstat_work, cpu));
per_cpu(vmstat_work, cpu).work.func = NULL;
break;
case CPU_DOWN_FAILED:
#ifdef CONFIG_SMP
int cpu;
- refresh_zone_stat_thresholds();
register_cpu_notifier(&vmstat_notifier);
for_each_online_cpu(cpu)
return 0;
}
module_init(setup_vmstat)
+
+#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_COMPACTION)
+#include <linux/debugfs.h>
+
+static struct dentry *extfrag_debug_root;
+
+/*
+ * Return an index indicating how much of the available free memory is
+ * unusable for an allocation of the requested size.
+ */
+static int unusable_free_index(unsigned int order,
+ struct contig_page_info *info)
+{
+ /* No free memory is interpreted as all free memory is unusable */
+ if (info->free_pages == 0)
+ return 1000;
+
+ /*
+ * Index should be a value between 0 and 1. Return a value to 3
+ * decimal places.
+ *
+ * 0 => no fragmentation
+ * 1 => high fragmentation
+ */
+ return div_u64((info->free_pages - (info->free_blocks_suitable << order)) * 1000ULL, info->free_pages);
+
+}
+
+static void unusable_show_print(struct seq_file *m,
+ pg_data_t *pgdat, struct zone *zone)
+{
+ unsigned int order;
+ int index;
+ struct contig_page_info info;
+
+ seq_printf(m, "Node %d, zone %8s ",
+ pgdat->node_id,
+ zone->name);
+ for (order = 0; order < MAX_ORDER; ++order) {
+ fill_contig_page_info(zone, order, &info);
+ index = unusable_free_index(order, &info);
+ seq_printf(m, "%d.%03d ", index / 1000, index % 1000);
+ }
+
+ seq_putc(m, '\n');
+}
+
+/*
+ * Display unusable free space index
+ *
+ * The unusable free space index measures how much of the available free
+ * memory cannot be used to satisfy an allocation of a given size and is a
+ * value between 0 and 1. The higher the value, the more of free memory is
+ * unusable and by implication, the worse the external fragmentation is. This
+ * can be expressed as a percentage by multiplying by 100.
+ */
+static int unusable_show(struct seq_file *m, void *arg)
+{
+ pg_data_t *pgdat = (pg_data_t *)arg;
+
+ /* check memoryless node */
+ if (!node_state(pgdat->node_id, N_HIGH_MEMORY))
+ return 0;
+
+ walk_zones_in_node(m, pgdat, unusable_show_print);
+
+ return 0;
+}
+
+static const struct seq_operations unusable_op = {
+ .start = frag_start,
+ .next = frag_next,
+ .stop = frag_stop,
+ .show = unusable_show,
+};
+
+static int unusable_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &unusable_op);
+}
+
+static const struct file_operations unusable_file_ops = {
+ .open = unusable_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static void extfrag_show_print(struct seq_file *m,
+ pg_data_t *pgdat, struct zone *zone)
+{
+ unsigned int order;
+ int index;
+
+ /* Alloc on stack as interrupts are disabled for zone walk */
+ struct contig_page_info info;
+
+ seq_printf(m, "Node %d, zone %8s ",
+ pgdat->node_id,
+ zone->name);
+ for (order = 0; order < MAX_ORDER; ++order) {
+ fill_contig_page_info(zone, order, &info);
+ index = __fragmentation_index(order, &info);
+ seq_printf(m, "%d.%03d ", index / 1000, index % 1000);
+ }
+
+ seq_putc(m, '\n');
+}
+
+/*
+ * Display fragmentation index for orders that allocations would fail for
+ */
+static int extfrag_show(struct seq_file *m, void *arg)
+{
+ pg_data_t *pgdat = (pg_data_t *)arg;
+
+ walk_zones_in_node(m, pgdat, extfrag_show_print);
+
+ return 0;
+}
+
+static const struct seq_operations extfrag_op = {
+ .start = frag_start,
+ .next = frag_next,
+ .stop = frag_stop,
+ .show = extfrag_show,
+};
+
+static int extfrag_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &extfrag_op);
+}
+
+static const struct file_operations extfrag_file_ops = {
+ .open = extfrag_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static int __init extfrag_debug_init(void)
+{
+ extfrag_debug_root = debugfs_create_dir("extfrag", NULL);
+ if (!extfrag_debug_root)
+ return -ENOMEM;
+
+ if (!debugfs_create_file("unusable_index", 0444,
+ extfrag_debug_root, NULL, &unusable_file_ops))
+ return -ENOMEM;
+
+ if (!debugfs_create_file("extfrag_index", 0444,
+ extfrag_debug_root, NULL, &extfrag_file_ops))
+ return -ENOMEM;
+
+ return 0;
+}
+
+module_init(extfrag_debug_init);
+#endif