1 files changed, 90 insertions, 39 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index fd47494cb989..e0e84924171b 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -53,6 +53,7 @@ struct pglist_data *pgdat_list __read_mostly;
 unsigned long totalram_pages __read_mostly;
 unsigned long totalhigh_pages __read_mostly;
 long nr_swap_pages;
+int percpu_pagelist_fraction;
 
 static void fastcall free_hot_cold_page(struct page *page, int cold);
 
@@ -307,7 +308,7 @@ static inline int page_is_buddy(struct page *page, int order)
  * -- wli
  */
 
-static inline void __free_pages_bulk (struct page *page,
+static inline void __free_one_page(struct page *page,
                 struct zone *zone, unsigned int order)
 {
         unsigned long page_idx;
@@ -382,40 +383,42 @@ static inline int free_pages_check(struct page *page)
  * And clear the zone's pages_scanned counter, to hold off the "all pages are
  * pinned" detection logic.
  */
-static int
-free_pages_bulk(struct zone *zone, int count,
-                struct list_head *list, unsigned int order)
+static void free_pages_bulk(struct zone *zone, int count,
+                                        struct list_head *list, int order)
 {
-        struct page *page = NULL;
-        int ret = 0;
-
         spin_lock(&zone->lock);
         zone->all_unreclaimable = 0;
         zone->pages_scanned = 0;
-        while (!list_empty(list) && count--) {
+        while (count--) {
+                struct page *page;
+
+                BUG_ON(list_empty(list));
                 page = list_entry(list->prev, struct page, lru);
-                /* have to delete it as __free_pages_bulk list manipulates */
+                /* have to delete it as __free_one_page list manipulates */
                 list_del(&page->lru);
-                __free_pages_bulk(page, zone, order);
-                ret++;
+                __free_one_page(page, zone, order);
         }
         spin_unlock(&zone->lock);
-        return ret;
 }
 
-void __free_pages_ok(struct page *page, unsigned int order)
+static void free_one_page(struct zone *zone, struct page *page, int order)
 {
-        unsigned long flags;
         LIST_HEAD(list);
+        list_add(&page->lru, &list);
+        free_pages_bulk(zone, 1, &list, order);
+}
+
+static void __free_pages_ok(struct page *page, unsigned int order)
+{
+        unsigned long flags;
         int i;
         int reserved = 0;
 
         arch_free_page(page, order);
 
 #ifndef CONFIG_MMU
-        if (order > 0)
-                for (i = 1 ; i < (1 << order) ; ++i)
-                        __put_page(page + i);
+        for (i = 1 ; i < (1 << order) ; ++i)
+                __put_page(page + i);
 #endif
 
         for (i = 0 ; i < (1 << order) ; ++i)
@@ -423,11 +426,10 @@ void __free_pages_ok(struct page *page, unsigned int order)
         if (reserved)
                 return;
 
-        list_add(&page->lru, &list);
-        kernel_map_pages(page, 1<<order, 0);
+        kernel_map_pages(page, 1 << order, 0);
         local_irq_save(flags);
         __mod_page_state(pgfree, 1 << order);
-        free_pages_bulk(page_zone(page), 1, &list, order);
+        free_one_page(page_zone(page), page, order);
         local_irq_restore(flags);
 }
 
@@ -596,14 +598,13 @@ void drain_remote_pages(void)
                 if (zone->zone_pgdat->node_id == numa_node_id())
                         continue;
 
-                pset = zone->pageset[smp_processor_id()];
+                pset = zone_pcp(zone, smp_processor_id());
                 for (i = 0; i < ARRAY_SIZE(pset->pcp); i++) {
                         struct per_cpu_pages *pcp;
 
                         pcp = &pset->pcp[i];
-                        if (pcp->count)
-                                pcp->count -= free_pages_bulk(zone, pcp->count,
-                                                &pcp->list, 0);
+                        free_pages_bulk(zone, pcp->count, &pcp->list, 0);
+                        pcp->count = 0;
                 }
         }
         local_irq_restore(flags);
@@ -626,8 +627,8 @@ static void __drain_pages(unsigned int cpu)
 
                         pcp = &pset->pcp[i];
                         local_irq_save(flags);
-                        pcp->count -= free_pages_bulk(zone, pcp->count,
-                                                &pcp->list, 0);
+                        free_pages_bulk(zone, pcp->count, &pcp->list, 0);
+                        pcp->count = 0;
                         local_irq_restore(flags);
                 }
         }
@@ -718,8 +719,10 @@ static void fastcall free_hot_cold_page(struct page *page, int cold)
         __inc_page_state(pgfree);
         list_add(&page->lru, &pcp->list);
         pcp->count++;
-        if (pcp->count >= pcp->high)
-                pcp->count -= free_pages_bulk(zone, pcp->batch, &pcp->list, 0);
+        if (pcp->count >= pcp->high) {
+                free_pages_bulk(zone, pcp->batch, &pcp->list, 0);
+                pcp->count -= pcp->batch;
+        }
         local_irq_restore(flags);
         put_cpu();
 }
@@ -758,7 +761,7 @@ static struct page *buffered_rmqueue(struct zonelist *zonelist,
 
 again:
         cpu  = get_cpu();
-        if (order == 0) {
+        if (likely(order == 0)) {
                 struct per_cpu_pages *pcp;
 
                 pcp = &zone_pcp(zone, cpu)->pcp[cold];
@@ -973,6 +976,7 @@ rebalance:
         cond_resched();
 
         /* We now go into synchronous reclaim */
+        cpuset_memory_pressure_bump();
         p->flags |= PF_MEMALLOC;
         reclaim_state.reclaimed_slab = 0;
         p->reclaim_state = &reclaim_state;
@@ -1204,6 +1208,7 @@ static void __get_page_state(struct page_state *ret, int nr, cpumask_t *cpumask)
         int cpu = 0;
 
         memset(ret, 0, sizeof(*ret));
+        cpus_and(*cpumask, *cpumask, cpu_online_map);
 
         cpu = first_cpu(*cpumask);
         while (cpu < NR_CPUS) {
@@ -1256,7 +1261,7 @@ unsigned long read_page_state_offset(unsigned long offset)
         unsigned long ret = 0;
         int cpu;
 
-        for_each_cpu(cpu) {
+        for_each_online_cpu(cpu) {
                 unsigned long in;
 
                 in = (unsigned long)&per_cpu(page_states, cpu) + offset;
@@ -1830,6 +1835,24 @@ inline void setup_pageset(struct per_cpu_pageset *p, unsigned long batch)
         INIT_LIST_HEAD(&pcp->list);
 }
 
+/*
+ * setup_pagelist_highmark() sets the high water mark for hot per_cpu_pagelist
+ * to the value high for the pageset p.
+ */
+
+static void setup_pagelist_highmark(struct per_cpu_pageset *p,
+                                unsigned long high)
+{
+        struct per_cpu_pages *pcp;
+
+        pcp = &p->pcp[0]; /* hot list */
+        pcp->high = high;
+        pcp->batch = max(1UL, high/4);
+        if ((high/4) > (PAGE_SHIFT * 8))
+                pcp->batch = PAGE_SHIFT * 8;
+}
+
+
 #ifdef CONFIG_NUMA
 /*
  * Boot pageset table. One per cpu which is going to be used for all
@@ -1861,12 +1884,16 @@ static int __devinit process_zones(int cpu)
 
         for_each_zone(zone) {
 
-                zone->pageset[cpu] = kmalloc_node(sizeof(struct per_cpu_pageset),
+                zone_pcp(zone, cpu) = kmalloc_node(sizeof(struct per_cpu_pageset),
                                          GFP_KERNEL, cpu_to_node(cpu));
-                if (!zone->pageset[cpu])
+                if (!zone_pcp(zone, cpu))
                         goto bad;
 
-                setup_pageset(zone->pageset[cpu], zone_batchsize(zone));
+                setup_pageset(zone_pcp(zone, cpu), zone_batchsize(zone));
+
+                if (percpu_pagelist_fraction)
+                        setup_pagelist_highmark(zone_pcp(zone, cpu),
+                                (zone->present_pages / percpu_pagelist_fraction));
         }
 
         return 0;
@@ -1874,15 +1901,14 @@ bad:
         for_each_zone(dzone) {
                 if (dzone == zone)
                         break;
-                kfree(dzone->pageset[cpu]);
-                dzone->pageset[cpu] = NULL;
+                kfree(zone_pcp(dzone, cpu));
+                zone_pcp(dzone, cpu) = NULL;
         }
         return -ENOMEM;
 }
 
 static inline void free_zone_pagesets(int cpu)
 {
-#ifdef CONFIG_NUMA
         struct zone *zone;
 
         for_each_zone(zone) {
@@ -1891,7 +1917,6 @@ static inline void free_zone_pagesets(int cpu)
                 zone_pcp(zone, cpu) = NULL;
                 kfree(pset);
         }
-#endif
 }
 
 static int __devinit pageset_cpuup_callback(struct notifier_block *nfb,
@@ -1962,7 +1987,7 @@ static __devinit void zone_pcp_init(struct zone *zone)
         for (cpu = 0; cpu < NR_CPUS; cpu++) {
 #ifdef CONFIG_NUMA
                 /* Early boot. Slab allocator not functional yet */
-                zone->pageset[cpu] = &boot_pageset[cpu];
+                zone_pcp(zone, cpu) = &boot_pageset[cpu];
                 setup_pageset(&boot_pageset[cpu],0);
 #else
                 setup_pageset(zone_pcp(zone,cpu), batch);
@@ -2205,7 +2230,7 @@ static int zoneinfo_show(struct seq_file *m, void *arg)
                 seq_printf(m,
                            ")"
                            "\n  pagesets");
-                for (i = 0; i < ARRAY_SIZE(zone->pageset); i++) {
+                for_each_online_cpu(i) {
                         struct per_cpu_pageset *pageset;
                         int j;
 
@@ -2568,6 +2593,32 @@ int lowmem_reserve_ratio_sysctl_handler(ctl_table *table, int write,
         return 0;
 }
 
+/*
+ * percpu_pagelist_fraction - changes the pcp->high for each zone on each
+ * cpu.  It is the fraction of total pages in each zone that a hot per cpu pagelist
+ * can have before it gets flushed back to buddy allocator.
+ */
+
+int percpu_pagelist_fraction_sysctl_handler(ctl_table *table, int write,
+        struct file *file, void __user *buffer, size_t *length, loff_t *ppos)
+{
+        struct zone *zone;
+        unsigned int cpu;
+        int ret;
+
+        ret = proc_dointvec_minmax(table, write, file, buffer, length, ppos);
+        if (!write || (ret == -EINVAL))
+                return ret;
+        for_each_zone(zone) {
+                for_each_online_cpu(cpu) {
+                        unsigned long  high;
+                        high = zone->present_pages / percpu_pagelist_fraction;
+                        setup_pagelist_highmark(zone_pcp(zone, cpu), high);
+                }
+        }
+        return 0;
+}
+
 __initdata int hashdist = HASHDIST_DEFAULT;
 
 #ifdef CONFIG_NUMA