#include <linux/config.h>
#include <linux/mm.h>
#include <linux/module.h>
+#include <linux/cpu.h>
void __get_zone_counts(unsigned long *active, unsigned long *inactive,
unsigned long *free, struct pglist_data *pgdat)
{
sum_vm_events(ret, &cpu_online_map);
}
+EXPORT_SYMBOL_GPL(all_vm_events);
#ifdef CONFIG_HOTPLUG
/*
#ifdef CONFIG_SMP
-#define STAT_THRESHOLD 32
+static int calculate_threshold(struct zone *zone)
+{
+ int threshold;
+ int mem; /* memory in 128 MB units */
+
+ /*
+ * The threshold scales with the number of processors and the amount
+ * of memory per zone. More memory means that we can defer updates for
+ * longer, more processors could lead to more contention.
+ * fls() is used to have a cheap way of logarithmic scaling.
+ *
+ * Some sample thresholds:
+ *
+ * Threshold Processors (fls) Zonesize fls(mem+1)
+ * ------------------------------------------------------------------
+ * 8 1 1 0.9-1 GB 4
+ * 16 2 2 0.9-1 GB 4
+ * 20 2 2 1-2 GB 5
+ * 24 2 2 2-4 GB 6
+ * 28 2 2 4-8 GB 7
+ * 32 2 2 8-16 GB 8
+ * 4 2 2 <128M 1
+ * 30 4 3 2-4 GB 5
+ * 48 4 3 8-16 GB 8
+ * 32 8 4 1-2 GB 4
+ * 32 8 4 0.9-1GB 4
+ * 10 16 5 <128M 1
+ * 40 16 5 900M 4
+ * 70 64 7 2-4 GB 5
+ * 84 64 7 4-8 GB 6
+ * 108 512 9 4-8 GB 6
+ * 125 1024 10 8-16 GB 8
+ * 125 1024 10 16-32 GB 9
+ */
+
+ mem = zone->present_pages >> (27 - PAGE_SHIFT);
+
+ threshold = 2 * fls(num_online_cpus()) * (1 + fls(mem));
+
+ /*
+ * Maximum threshold is 125
+ */
+ threshold = min(125, threshold);
+
+ return threshold;
+}
/*
- * Determine pointer to currently valid differential byte given a zone and
- * the item number.
- *
- * Preemption must be off
+ * Refresh the thresholds for each zone.
*/
-static inline s8 *diff_pointer(struct zone *zone, enum zone_stat_item item)
+static void refresh_zone_stat_thresholds(void)
{
- return &zone_pcp(zone, smp_processor_id())->vm_stat_diff[item];
+ struct zone *zone;
+ int cpu;
+ int threshold;
+
+ for_each_zone(zone) {
+
+ if (!zone->present_pages)
+ continue;
+
+ threshold = calculate_threshold(zone);
+
+ for_each_online_cpu(cpu)
+ zone_pcp(zone, cpu)->stat_threshold = threshold;
+ }
}
/*
void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
int delta)
{
- s8 *p;
+ struct per_cpu_pageset *pcp = zone_pcp(zone, smp_processor_id());
+ s8 *p = pcp->vm_stat_diff + item;
long x;
- p = diff_pointer(zone, item);
x = delta + *p;
- if (unlikely(x > STAT_THRESHOLD || x < -STAT_THRESHOLD)) {
+ if (unlikely(x > pcp->stat_threshold || x < -pcp->stat_threshold)) {
zone_page_state_add(x, zone, item);
x = 0;
}
-
*p = x;
}
EXPORT_SYMBOL(__mod_zone_page_state);
* No overflow check is necessary and therefore the differential can be
* incremented or decremented in place which may allow the compilers to
* generate better code.
- *
* The increment or decrement is known and therefore one boundary check can
* be omitted.
*
+ * NOTE: These functions are very performance sensitive. Change only
+ * with care.
+ *
* Some processors have inc/dec instructions that are atomic vs an interrupt.
* However, the code must first determine the differential location in a zone
* based on the processor number and then inc/dec the counter. There is no
*/
static void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
{
- s8 *p = diff_pointer(zone, item);
+ struct per_cpu_pageset *pcp = zone_pcp(zone, smp_processor_id());
+ s8 *p = pcp->vm_stat_diff + item;
(*p)++;
- if (unlikely(*p > STAT_THRESHOLD)) {
- zone_page_state_add(*p, zone, item);
- *p = 0;
+ if (unlikely(*p > pcp->stat_threshold)) {
+ int overstep = pcp->stat_threshold / 2;
+
+ zone_page_state_add(*p + overstep, zone, item);
+ *p = -overstep;
}
}
void __dec_zone_page_state(struct page *page, enum zone_stat_item item)
{
struct zone *zone = page_zone(page);
- s8 *p = diff_pointer(zone, item);
+ struct per_cpu_pageset *pcp = zone_pcp(zone, smp_processor_id());
+ s8 *p = pcp->vm_stat_diff + item;
(*p)--;
- if (unlikely(*p < -STAT_THRESHOLD)) {
- zone_page_state_add(*p, zone, item);
- *p = 0;
+ if (unlikely(*p < - pcp->stat_threshold)) {
+ int overstep = pcp->stat_threshold / 2;
+
+ zone_page_state_add(*p - overstep, zone, item);
+ *p = overstep;
}
}
EXPORT_SYMBOL(__dec_zone_page_state);
void dec_zone_page_state(struct page *page, enum zone_stat_item item)
{
unsigned long flags;
- struct zone *zone;
- s8 *p;
- zone = page_zone(page);
local_irq_save(flags);
- p = diff_pointer(zone, item);
-
- (*p)--;
-
- if (unlikely(*p < -STAT_THRESHOLD)) {
- zone_page_state_add(*p, zone, item);
- *p = 0;
- }
+ __dec_zone_page_state(page, item);
local_irq_restore(flags);
}
EXPORT_SYMBOL(dec_zone_page_state);
for_each_zone(zone) {
struct per_cpu_pageset *pcp;
+ if (!populated_zone(zone))
+ continue;
+
pcp = zone_pcp(zone, cpu);
for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
__inc_zone_state(z, NUMA_MISS);
__inc_zone_state(zonelist->zones[0], NUMA_FOREIGN);
}
- if (z->zone_pgdat == NODE_DATA(numa_node_id()))
+ if (z->node == numa_node_id())
__inc_zone_state(z, NUMA_LOCAL);
else
__inc_zone_state(z, NUMA_OTHER);
.show = frag_show,
};
+#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) xx "_dma", TEXT_FOR_DMA32(xx) xx "_normal", \
+ TEXT_FOR_HIGHMEM(xx)
+
static char *vmstat_text[] = {
/* Zoned VM counters */
"nr_anon_pages",
"nr_mapped",
"nr_file_pages",
- "nr_slab",
+ "nr_slab_reclaimable",
+ "nr_slab_unreclaimable",
"nr_page_table_pages",
"nr_dirty",
"nr_writeback",
"nr_unstable",
"nr_bounce",
+ "nr_vmscan_write",
#ifdef CONFIG_NUMA
"numa_hit",
"pswpin",
"pswpout",
- "pgalloc_dma",
- "pgalloc_dma32",
- "pgalloc_normal",
- "pgalloc_high",
+ TEXTS_FOR_ZONES("pgalloc")
"pgfree",
"pgactivate",
"pgfault",
"pgmajfault",
- "pgrefill_dma",
- "pgrefill_dma32",
- "pgrefill_normal",
- "pgrefill_high",
-
- "pgsteal_dma",
- "pgsteal_dma32",
- "pgsteal_normal",
- "pgsteal_high",
-
- "pgscan_kswapd_dma",
- "pgscan_kswapd_dma32",
- "pgscan_kswapd_normal",
- "pgscan_kswapd_high",
-
- "pgscan_direct_dma",
- "pgscan_direct_dma32",
- "pgscan_direct_normal",
- "pgscan_direct_high",
+ TEXTS_FOR_ZONES("pgrefill")
+ TEXTS_FOR_ZONES("pgsteal")
+ TEXTS_FOR_ZONES("pgscan_kswapd")
+ TEXTS_FOR_ZONES("pgscan_direct")
"pginodesteal",
"slabs_scanned",
pageset->pcp[j].high,
pageset->pcp[j].batch);
}
+#ifdef CONFIG_SMP
+ seq_printf(m, "\n vm stats threshold: %d",
+ pageset->stat_threshold);
+#endif
}
seq_printf(m,
"\n all_unreclaimable: %u"
#endif /* CONFIG_PROC_FS */
+#ifdef CONFIG_SMP
+/*
+ * Use the cpu notifier to insure that the thresholds are recalculated
+ * when necessary.
+ */
+static int __cpuinit vmstat_cpuup_callback(struct notifier_block *nfb,
+ unsigned long action,
+ void *hcpu)
+{
+ switch (action) {
+ case CPU_UP_PREPARE:
+ case CPU_UP_CANCELED:
+ case CPU_DEAD:
+ refresh_zone_stat_thresholds();
+ break;
+ default:
+ break;
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block __cpuinitdata vmstat_notifier =
+ { &vmstat_cpuup_callback, NULL, 0 };
+
+int __init setup_vmstat(void)
+{
+ refresh_zone_stat_thresholds();
+ register_cpu_notifier(&vmstat_notifier);
+ return 0;
+}
+module_init(setup_vmstat)
+#endif
git.openpandora.org / pandora-kernel.git / blobdiff