Move free pages between lists on steal
[powerpc.git] / mm / page_alloc.c
index e69f19e..d575a3e 100644 (file)
@@ -158,6 +158,39 @@ int nr_node_ids __read_mostly = MAX_NUMNODES;
 EXPORT_SYMBOL(nr_node_ids);
 #endif
 
+#ifdef CONFIG_PAGE_GROUP_BY_MOBILITY
+static inline int get_pageblock_migratetype(struct page *page)
+{
+       return get_pageblock_flags_group(page, PB_migrate, PB_migrate_end);
+}
+
+static void set_pageblock_migratetype(struct page *page, int migratetype)
+{
+       set_pageblock_flags_group(page, (unsigned long)migratetype,
+                                       PB_migrate, PB_migrate_end);
+}
+
+static inline int gfpflags_to_migratetype(gfp_t gfp_flags)
+{
+       return ((gfp_flags & __GFP_MOVABLE) != 0);
+}
+
+#else
+static inline int get_pageblock_migratetype(struct page *page)
+{
+       return MIGRATE_UNMOVABLE;
+}
+
+static void set_pageblock_migratetype(struct page *page, int migratetype)
+{
+}
+
+static inline int gfpflags_to_migratetype(gfp_t gfp_flags)
+{
+       return MIGRATE_UNMOVABLE;
+}
+#endif /* CONFIG_PAGE_GROUP_BY_MOBILITY */
+
 #ifdef CONFIG_DEBUG_VM
 static int page_outside_zone_boundaries(struct zone *zone, struct page *page)
 {
@@ -412,6 +445,7 @@ static inline void __free_one_page(struct page *page,
 {
        unsigned long page_idx;
        int order_size = 1 << order;
+       int migratetype = get_pageblock_migratetype(page);
 
        if (unlikely(PageCompound(page)))
                destroy_compound_page(page, order);
@@ -424,7 +458,6 @@ static inline void __free_one_page(struct page *page,
        __mod_zone_page_state(zone, NR_FREE_PAGES, order_size);
        while (order < MAX_ORDER-1) {
                unsigned long combined_idx;
-               struct free_area *area;
                struct page *buddy;
 
                buddy = __page_find_buddy(page, page_idx, order);
@@ -432,8 +465,7 @@ static inline void __free_one_page(struct page *page,
                        break;          /* Move the buddy up one level. */
 
                list_del(&buddy->lru);
-               area = zone->free_area + order;
-               area->nr_free--;
+               zone->free_area[order].nr_free--;
                rmv_page_order(buddy);
                combined_idx = __find_combined_index(page_idx, order);
                page = page + (combined_idx - page_idx);
@@ -441,7 +473,8 @@ static inline void __free_one_page(struct page *page,
                order++;
        }
        set_page_order(page, order);
-       list_add(&page->lru, &zone->free_area[order].free_list);
+       list_add(&page->lru,
+               &zone->free_area[order].free_list[migratetype]);
        zone->free_area[order].nr_free++;
 }
 
@@ -575,7 +608,8 @@ void fastcall __init __free_pages_bootmem(struct page *page, unsigned int order)
  * -- wli
  */
 static inline void expand(struct zone *zone, struct page *page,
-       int low, int high, struct free_area *area)
+       int low, int high, struct free_area *area,
+       int migratetype)
 {
        unsigned long size = 1 << high;
 
@@ -584,7 +618,7 @@ static inline void expand(struct zone *zone, struct page *page,
                high--;
                size >>= 1;
                VM_BUG_ON(bad_range(zone, &page[size]));
-               list_add(&page[size].lru, &area->free_list);
+               list_add(&page[size].lru, &area->free_list[migratetype]);
                area->nr_free++;
                set_page_order(&page[size], high);
        }
@@ -636,31 +670,171 @@ static int prep_new_page(struct page *page, int order, gfp_t gfp_flags)
        return 0;
 }
 
+#ifdef CONFIG_PAGE_GROUP_BY_MOBILITY
+/*
+ * This array describes the order lists are fallen back to when
+ * the free lists for the desirable migrate type are depleted
+ */
+static int fallbacks[MIGRATE_TYPES][MIGRATE_TYPES-1] = {
+       [MIGRATE_UNMOVABLE] = { MIGRATE_MOVABLE   },
+       [MIGRATE_MOVABLE]   = { MIGRATE_UNMOVABLE },
+};
+
+/*
+ * Move the free pages in a range to the free lists of the requested type.
+ * Note that start_page and end_pages are not aligned in a MAX_ORDER_NR_PAGES
+ * boundary. If alignment is required, use move_freepages_block()
+ */
+int move_freepages(struct zone *zone,
+                       struct page *start_page, struct page *end_page,
+                       int migratetype)
+{
+       struct page *page;
+       unsigned long order;
+       int blocks_moved = 0;
+
+#ifndef CONFIG_HOLES_IN_ZONE
+       /*
+        * page_zone is not safe to call in this context when
+        * CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant
+        * anyway as we check zone boundaries in move_freepages_block().
+        * Remove at a later date when no bug reports exist related to
+        * CONFIG_PAGE_GROUP_BY_MOBILITY
+        */
+       BUG_ON(page_zone(start_page) != page_zone(end_page));
+#endif
+
+       for (page = start_page; page <= end_page;) {
+               if (!pfn_valid_within(page_to_pfn(page))) {
+                       page++;
+                       continue;
+               }
+
+               if (!PageBuddy(page)) {
+                       page++;
+                       continue;
+               }
+
+               order = page_order(page);
+               list_del(&page->lru);
+               list_add(&page->lru,
+                       &zone->free_area[order].free_list[migratetype]);
+               page += 1 << order;
+               blocks_moved++;
+       }
+
+       return blocks_moved;
+}
+
+int move_freepages_block(struct zone *zone, struct page *page, int migratetype)
+{
+       unsigned long start_pfn, end_pfn;
+       struct page *start_page, *end_page;
+
+       start_pfn = page_to_pfn(page);
+       start_pfn = start_pfn & ~(MAX_ORDER_NR_PAGES-1);
+       start_page = pfn_to_page(start_pfn);
+       end_page = start_page + MAX_ORDER_NR_PAGES - 1;
+       end_pfn = start_pfn + MAX_ORDER_NR_PAGES - 1;
+
+       /* Do not cross zone boundaries */
+       if (start_pfn < zone->zone_start_pfn)
+               start_page = page;
+       if (end_pfn >= zone->zone_start_pfn + zone->spanned_pages)
+               return 0;
+
+       return move_freepages(zone, start_page, end_page, migratetype);
+}
+
+/* Remove an element from the buddy allocator from the fallback list */
+static struct page *__rmqueue_fallback(struct zone *zone, int order,
+                                               int start_migratetype)
+{
+       struct free_area * area;
+       int current_order;
+       struct page *page;
+       int migratetype, i;
+
+       /* Find the largest possible block of pages in the other list */
+       for (current_order = MAX_ORDER-1; current_order >= order;
+                                               --current_order) {
+               for (i = 0; i < MIGRATE_TYPES - 1; i++) {
+                       migratetype = fallbacks[start_migratetype][i];
+
+                       area = &(zone->free_area[current_order]);
+                       if (list_empty(&area->free_list[migratetype]))
+                               continue;
+
+                       page = list_entry(area->free_list[migratetype].next,
+                                       struct page, lru);
+                       area->nr_free--;
+
+                       /*
+                        * If breaking a large block of pages, move all free
+                        * pages to the preferred allocation list
+                        */
+                       if (unlikely(current_order >= MAX_ORDER / 2)) {
+                               migratetype = start_migratetype;
+                               move_freepages_block(zone, page, migratetype);
+                       }
+
+                       /* Remove the page from the freelists */
+                       list_del(&page->lru);
+                       rmv_page_order(page);
+                       __mod_zone_page_state(zone, NR_FREE_PAGES,
+                                                       -(1UL << order));
+
+                       if (current_order == MAX_ORDER - 1)
+                               set_pageblock_migratetype(page,
+                                                       start_migratetype);
+
+                       expand(zone, page, order, current_order, area, migratetype);
+                       return page;
+               }
+       }
+
+       return NULL;
+}
+#else
+static struct page *__rmqueue_fallback(struct zone *zone, int order,
+                                               int start_migratetype)
+{
+       return NULL;
+}
+#endif /* CONFIG_PAGE_GROUP_BY_MOBILITY */
+
 /* 
  * Do the hard work of removing an element from the buddy allocator.
  * Call me with the zone->lock already held.
  */
-static struct page *__rmqueue(struct zone *zone, unsigned int order)
+static struct page *__rmqueue(struct zone *zone, unsigned int order,
+                                               int migratetype)
 {
        struct free_area * area;
        unsigned int current_order;
        struct page *page;
 
+       /* Find a page of the appropriate size in the preferred list */
        for (current_order = order; current_order < MAX_ORDER; ++current_order) {
-               area = zone->free_area + current_order;
-               if (list_empty(&area->free_list))
+               area = &(zone->free_area[current_order]);
+               if (list_empty(&area->free_list[migratetype]))
                        continue;
 
-               page = list_entry(area->free_list.next, struct page, lru);
+               page = list_entry(area->free_list[migratetype].next,
+                                                       struct page, lru);
                list_del(&page->lru);
                rmv_page_order(page);
                area->nr_free--;
                __mod_zone_page_state(zone, NR_FREE_PAGES, - (1UL << order));
-               expand(zone, page, order, current_order, area);
-               return page;
+               expand(zone, page, order, current_order, area, migratetype);
+               goto got_page;
        }
 
-       return NULL;
+       page = __rmqueue_fallback(zone, order, migratetype);
+
+got_page:
+
+       return page;
 }
 
 /* 
@@ -669,16 +843,18 @@ static struct page *__rmqueue(struct zone *zone, unsigned int order)
  * Returns the number of new pages which were placed at *list.
  */
 static int rmqueue_bulk(struct zone *zone, unsigned int order, 
-                       unsigned long count, struct list_head *list)
+                       unsigned long count, struct list_head *list,
+                       int migratetype)
 {
        int i;
        
        spin_lock(&zone->lock);
        for (i = 0; i < count; ++i) {
-               struct page *page = __rmqueue(zone, order);
+               struct page *page = __rmqueue(zone, order, migratetype);
                if (unlikely(page == NULL))
                        break;
-               list_add_tail(&page->lru, list);
+               list_add(&page->lru, list);
+               set_page_private(page, migratetype);
        }
        spin_unlock(&zone->lock);
        return i;
@@ -740,7 +916,7 @@ void mark_free_pages(struct zone *zone)
 {
        unsigned long pfn, max_zone_pfn;
        unsigned long flags;
-       int order;
+       int order, t;
        struct list_head *curr;
 
        if (!zone->spanned_pages)
@@ -757,18 +933,20 @@ void mark_free_pages(struct zone *zone)
                                swsusp_unset_page_free(page);
                }
 
-       for (order = MAX_ORDER - 1; order >= 0; --order)
-               list_for_each(curr, &zone->free_area[order].free_list) {
+       for_each_migratetype_order(order, t) {
+               list_for_each(curr, &zone->free_area[order].free_list[t]) {
                        unsigned long i;
 
                        pfn = page_to_pfn(list_entry(curr, struct page, lru));
                        for (i = 0; i < (1UL << order); i++)
                                swsusp_set_page_free(pfn_to_page(pfn + i));
                }
-
+       }
        spin_unlock_irqrestore(&zone->lock, flags);
 }
+#endif /* CONFIG_PM */
 
+#if defined(CONFIG_HIBERNATION) || defined(CONFIG_PAGE_GROUP_BY_MOBILITY)
 /*
  * Spill all of this CPU's per-cpu pages back into the buddy allocator.
  */
@@ -780,7 +958,28 @@ void drain_local_pages(void)
        __drain_pages(smp_processor_id());
        local_irq_restore(flags);       
 }
-#endif /* CONFIG_HIBERNATION */
+
+void smp_drain_local_pages(void *arg)
+{
+       drain_local_pages();
+}
+
+/*
+ * Spill all the per-cpu pages from all CPUs back into the buddy allocator
+ */
+void drain_all_local_pages(void)
+{
+       unsigned long flags;
+
+       local_irq_save(flags);
+       __drain_pages(smp_processor_id());
+       local_irq_restore(flags);
+
+       smp_call_function(smp_drain_local_pages, NULL, 0, 1);
+}
+#else
+void drain_all_local_pages(void) {}
+#endif /* CONFIG_HIBERNATION || CONFIG_PAGE_GROUP_BY_MOBILITY */
 
 /*
  * Free a 0-order page
@@ -805,6 +1004,7 @@ static void fastcall free_hot_cold_page(struct page *page, int cold)
        local_irq_save(flags);
        __count_vm_event(PGFREE);
        list_add(&page->lru, &pcp->list);
+       set_page_private(page, get_pageblock_migratetype(page));
        pcp->count++;
        if (pcp->count >= pcp->high) {
                free_pages_bulk(zone, pcp->batch, &pcp->list, 0);
@@ -854,6 +1054,7 @@ static struct page *buffered_rmqueue(struct zonelist *zonelist,
        struct page *page;
        int cold = !!(gfp_flags & __GFP_COLD);
        int cpu;
+       int migratetype = gfpflags_to_migratetype(gfp_flags);
 
 again:
        cpu  = get_cpu();
@@ -864,16 +1065,32 @@ again:
                local_irq_save(flags);
                if (!pcp->count) {
                        pcp->count = rmqueue_bulk(zone, 0,
-                                               pcp->batch, &pcp->list);
+                                       pcp->batch, &pcp->list, migratetype);
                        if (unlikely(!pcp->count))
                                goto failed;
                }
+
+#ifdef CONFIG_PAGE_GROUP_BY_MOBILITY
+               /* Find a page of the appropriate migrate type */
+               list_for_each_entry(page, &pcp->list, lru)
+                       if (page_private(page) == migratetype)
+                               break;
+
+               /* Allocate more to the pcp list if necessary */
+               if (unlikely(&page->lru == &pcp->list)) {
+                       pcp->count += rmqueue_bulk(zone, 0,
+                                       pcp->batch, &pcp->list, migratetype);
+                       page = list_entry(pcp->list.next, struct page, lru);
+               }
+#else
                page = list_entry(pcp->list.next, struct page, lru);
+#endif /* CONFIG_PAGE_GROUP_BY_MOBILITY */
+
                list_del(&page->lru);
                pcp->count--;
        } else {
                spin_lock_irqsave(&zone->lock, flags);
-               page = __rmqueue(zone, order);
+               page = __rmqueue(zone, order, migratetype);
                spin_unlock(&zone->lock);
                if (!page)
                        goto failed;
@@ -1354,6 +1571,9 @@ nofail_alloc:
 
        cond_resched();
 
+       if (order != 0)
+               drain_all_local_pages();
+
        if (likely(did_some_progress)) {
                page = get_page_from_freelist(gfp_mask, order,
                                                zonelist, alloc_flags);
@@ -2233,6 +2453,16 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
                init_page_count(page);
                reset_page_mapcount(page);
                SetPageReserved(page);
+
+               /*
+                * Mark the block movable so that blocks are reserved for
+                * movable at startup. This will force kernel allocations
+                * to reserve their blocks rather than leaking throughout
+                * the address space during boot when many long-lived
+                * kernel allocations are made
+                */
+               set_pageblock_migratetype(page, MIGRATE_MOVABLE);
+
                INIT_LIST_HEAD(&page->lru);
 #ifdef WANT_PAGE_VIRTUAL
                /* The shift won't overflow because ZONE_NORMAL is below 4G. */
@@ -2245,9 +2475,9 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
 static void __meminit zone_init_free_lists(struct pglist_data *pgdat,
                                struct zone *zone, unsigned long size)
 {
-       int order;
-       for (order = 0; order < MAX_ORDER ; order++) {
-               INIT_LIST_HEAD(&zone->free_area[order].free_list);
+       int order, t;
+       for_each_migratetype_order(order, t) {
+               INIT_LIST_HEAD(&zone->free_area[order].free_list[t]);
                zone->free_area[order].nr_free = 0;
        }
 }
@@ -2931,6 +3161,41 @@ static void __meminit calculate_node_totalpages(struct pglist_data *pgdat,
                                                        realtotalpages);
 }
 
+#ifndef CONFIG_SPARSEMEM
+/*
+ * Calculate the size of the zone->blockflags rounded to an unsigned long
+ * Start by making sure zonesize is a multiple of MAX_ORDER-1 by rounding up
+ * Then figure 1 NR_PAGEBLOCK_BITS worth of bits per MAX_ORDER-1, finally
+ * round what is now in bits to nearest long in bits, then return it in
+ * bytes.
+ */
+static unsigned long __init usemap_size(unsigned long zonesize)
+{
+       unsigned long usemapsize;
+
+       usemapsize = roundup(zonesize, MAX_ORDER_NR_PAGES);
+       usemapsize = usemapsize >> (MAX_ORDER-1);
+       usemapsize *= NR_PAGEBLOCK_BITS;
+       usemapsize = roundup(usemapsize, 8 * sizeof(unsigned long));
+
+       return usemapsize / 8;
+}
+
+static void __init setup_usemap(struct pglist_data *pgdat,
+                               struct zone *zone, unsigned long zonesize)
+{
+       unsigned long usemapsize = usemap_size(zonesize);
+       zone->pageblock_flags = NULL;
+       if (usemapsize) {
+               zone->pageblock_flags = alloc_bootmem_node(pgdat, usemapsize);
+               memset(zone->pageblock_flags, 0, usemapsize);
+       }
+}
+#else
+static void inline setup_usemap(struct pglist_data *pgdat,
+                               struct zone *zone, unsigned long zonesize) {}
+#endif /* CONFIG_SPARSEMEM */
+
 /*
  * Set up the zone data structures:
  *   - mark all pages reserved
@@ -3011,6 +3276,7 @@ static void __meminit free_area_init_core(struct pglist_data *pgdat,
                if (!size)
                        continue;
 
+               setup_usemap(pgdat, zone, size);
                ret = init_currently_empty_zone(zone, zone_start_pfn,
                                                size, MEMMAP_EARLY);
                BUG_ON(ret);
@@ -3991,4 +4257,79 @@ EXPORT_SYMBOL(pfn_to_page);
 EXPORT_SYMBOL(page_to_pfn);
 #endif /* CONFIG_OUT_OF_LINE_PFN_TO_PAGE */
 
+/* Return a pointer to the bitmap storing bits affecting a block of pages */
+static inline unsigned long *get_pageblock_bitmap(struct zone *zone,
+                                                       unsigned long pfn)
+{
+#ifdef CONFIG_SPARSEMEM
+       return __pfn_to_section(pfn)->pageblock_flags;
+#else
+       return zone->pageblock_flags;
+#endif /* CONFIG_SPARSEMEM */
+}
 
+static inline int pfn_to_bitidx(struct zone *zone, unsigned long pfn)
+{
+#ifdef CONFIG_SPARSEMEM
+       pfn &= (PAGES_PER_SECTION-1);
+       return (pfn >> (MAX_ORDER-1)) * NR_PAGEBLOCK_BITS;
+#else
+       pfn = pfn - zone->zone_start_pfn;
+       return (pfn >> (MAX_ORDER-1)) * NR_PAGEBLOCK_BITS;
+#endif /* CONFIG_SPARSEMEM */
+}
+
+/**
+ * get_pageblock_flags_group - Return the requested group of flags for the MAX_ORDER_NR_PAGES block of pages
+ * @page: The page within the block of interest
+ * @start_bitidx: The first bit of interest to retrieve
+ * @end_bitidx: The last bit of interest
+ * returns pageblock_bits flags
+ */
+unsigned long get_pageblock_flags_group(struct page *page,
+                                       int start_bitidx, int end_bitidx)
+{
+       struct zone *zone;
+       unsigned long *bitmap;
+       unsigned long pfn, bitidx;
+       unsigned long flags = 0;
+       unsigned long value = 1;
+
+       zone = page_zone(page);
+       pfn = page_to_pfn(page);
+       bitmap = get_pageblock_bitmap(zone, pfn);
+       bitidx = pfn_to_bitidx(zone, pfn);
+
+       for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1)
+               if (test_bit(bitidx + start_bitidx, bitmap))
+                       flags |= value;
+
+       return flags;
+}
+
+/**
+ * set_pageblock_flags_group - Set the requested group of flags for a MAX_ORDER_NR_PAGES block of pages
+ * @page: The page within the block of interest
+ * @start_bitidx: The first bit of interest
+ * @end_bitidx: The last bit of interest
+ * @flags: The flags to set
+ */
+void set_pageblock_flags_group(struct page *page, unsigned long flags,
+                                       int start_bitidx, int end_bitidx)
+{
+       struct zone *zone;
+       unsigned long *bitmap;
+       unsigned long pfn, bitidx;
+       unsigned long value = 1;
+
+       zone = page_zone(page);
+       pfn = page_to_pfn(page);
+       bitmap = get_pageblock_bitmap(zone, pfn);
+       bitidx = pfn_to_bitidx(zone, pfn);
+
+       for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1)
+               if (flags & value)
+                       __set_bit(bitidx + start_bitidx, bitmap);
+               else
+                       __clear_bit(bitidx + start_bitidx, bitmap);
+}