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-rw-r--r--mm/mempolicy.c10
-rw-r--r--mm/mempool.c9
-rw-r--r--mm/swap.c20
-rw-r--r--mm/swapfile.c3
-rw-r--r--mm/vmstat.c151
5 files changed, 158 insertions, 35 deletions
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index e07e27e846a2..a9963ceddd65 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1176,7 +1176,15 @@ static inline unsigned interleave_nid(struct mempolicy *pol,
if (vma) {
unsigned long off;
- off = vma->vm_pgoff;
+ /*
+ * for small pages, there is no difference between
+ * shift and PAGE_SHIFT, so the bit-shift is safe.
+ * for huge pages, since vm_pgoff is in units of small
+ * pages, we need to shift off the always 0 bits to get
+ * a useful offset.
+ */
+ BUG_ON(shift < PAGE_SHIFT);
+ off = vma->vm_pgoff >> (shift - PAGE_SHIFT);
off += (addr - vma->vm_start) >> shift;
return offset_il_node(pol, vma, off);
} else
diff --git a/mm/mempool.c b/mm/mempool.c
index fe6e05289cc5..ccd8cb8cd41f 100644
--- a/mm/mempool.c
+++ b/mm/mempool.c
@@ -238,8 +238,13 @@ repeat_alloc:
init_wait(&wait);
prepare_to_wait(&pool->wait, &wait, TASK_UNINTERRUPTIBLE);
smp_mb();
- if (!pool->curr_nr)
- io_schedule();
+ if (!pool->curr_nr) {
+ /*
+ * FIXME: this should be io_schedule(). The timeout is there
+ * as a workaround for some DM problems in 2.6.18.
+ */
+ io_schedule_timeout(5*HZ);
+ }
finish_wait(&pool->wait, &wait);
goto repeat_alloc;
diff --git a/mm/swap.c b/mm/swap.c
index 8fd095c4ae51..687686a61f7c 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -54,6 +54,26 @@ void put_page(struct page *page)
}
EXPORT_SYMBOL(put_page);
+/**
+ * put_pages_list(): release a list of pages
+ *
+ * Release a list of pages which are strung together on page.lru. Currently
+ * used by read_cache_pages() and related error recovery code.
+ *
+ * @pages: list of pages threaded on page->lru
+ */
+void put_pages_list(struct list_head *pages)
+{
+ while (!list_empty(pages)) {
+ struct page *victim;
+
+ victim = list_entry(pages->prev, struct page, lru);
+ list_del(&victim->lru);
+ page_cache_release(victim);
+ }
+}
+EXPORT_SYMBOL(put_pages_list);
+
/*
* Writeback is about to end against a page which has been marked for immediate
* reclaim. If it still appears to be reclaimable, move it to the tail of the
diff --git a/mm/swapfile.c b/mm/swapfile.c
index e70d6c6d6fee..f1f5ec783781 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -442,11 +442,12 @@ int swap_type_of(dev_t device)
if (!(swap_info[i].flags & SWP_WRITEOK))
continue;
+
if (!device) {
spin_unlock(&swap_lock);
return i;
}
- inode = swap_info->swap_file->f_dentry->d_inode;
+ inode = swap_info[i].swap_file->f_dentry->d_inode;
if (S_ISBLK(inode->i_mode) &&
device == MKDEV(imajor(inode), iminor(inode))) {
spin_unlock(&swap_lock);
diff --git a/mm/vmstat.c b/mm/vmstat.c
index dfdf24133901..c1b5f4106b38 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -12,6 +12,7 @@
#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)
@@ -114,17 +115,72 @@ EXPORT_SYMBOL(vm_stat);
#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;
+ }
}
/*
@@ -133,17 +189,16 @@ static inline s8 *diff_pointer(struct zone *zone, enum zone_stat_item item)
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);
@@ -172,10 +227,12 @@ 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
@@ -185,13 +242,16 @@ EXPORT_SYMBOL(mod_zone_page_state);
*/
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;
}
}
@@ -204,13 +264,16 @@ EXPORT_SYMBOL(__inc_zone_page_state);
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);
@@ -239,19 +302,9 @@ EXPORT_SYMBOL(inc_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);
@@ -525,6 +578,10 @@ static int zoneinfo_show(struct seq_file *m, void *arg)
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"
@@ -613,3 +670,35 @@ struct seq_operations vmstat_op = {
#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
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-08 08:48:47 +0000