From: Nick Piggin <nickpiggin@yahoo.com.au>
Keep track of the number of free pages of each order in the buddy allocator.
Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/include/linux/mmzone.h | 1 +
25-akpm/mm/page_alloc.c | 23 +++++++++--------------
2 files changed, 10 insertions(+), 14 deletions(-)
diff -puN include/linux/mmzone.h~mm-keep-count-of-free-areas include/linux/mmzone.h
--- 25/include/linux/mmzone.h~mm-keep-count-of-free-areas Wed Oct 27 15:45:34 2004
+++ 25-akpm/include/linux/mmzone.h Wed Oct 27 15:45:34 2004
@@ -23,6 +23,7 @@
struct free_area {
struct list_head free_list;
unsigned long *map;
+ unsigned long nr_free;
};
struct pglist_data;
diff -puN mm/page_alloc.c~mm-keep-count-of-free-areas mm/page_alloc.c
--- 25/mm/page_alloc.c~mm-keep-count-of-free-areas Wed Oct 27 15:45:34 2004
+++ 25-akpm/mm/page_alloc.c Wed Oct 27 15:45:34 2004
@@ -209,6 +209,7 @@ static inline void __free_pages_bulk (st
BUG_ON(bad_range(zone, buddy1));
BUG_ON(bad_range(zone, buddy2));
list_del(&buddy1->lru);
+ area->nr_free--;
mask <<= 1;
order++;
area++;
@@ -216,6 +217,7 @@ static inline void __free_pages_bulk (st
page_idx &= mask;
}
list_add(&(base + page_idx)->lru, &area->free_list);
+ area->nr_free++;
}
static inline void free_pages_check(const char *function, struct page *page)
@@ -317,6 +319,7 @@ expand(struct zone *zone, struct page *p
size >>= 1;
BUG_ON(bad_range(zone, &page[size]));
list_add(&page[size].lru, &area->free_list);
+ area->nr_free++;
MARK_USED(index + size, high, area);
}
return page;
@@ -380,6 +383,7 @@ static struct page *__rmqueue(struct zon
page = list_entry(area->free_list.next, struct page, lru);
list_del(&page->lru);
+ area->nr_free--;
index = page - zone->zone_mem_map;
if (current_order != MAX_ORDER-1)
MARK_USED(index, current_order, area);
@@ -1124,7 +1128,6 @@ void show_free_areas(void)
}
for_each_zone(zone) {
- struct list_head *elem;
unsigned long nr, flags, order, total = 0;
show_node(zone);
@@ -1136,9 +1139,7 @@ void show_free_areas(void)
spin_lock_irqsave(&zone->lock, flags);
for (order = 0; order < MAX_ORDER; order++) {
- nr = 0;
- list_for_each(elem, &zone->free_area[order].free_list)
- ++nr;
+ nr = zone->free_area[order].nr_free;
total += nr << order;
printk("%lu*%lukB ", nr, K(1UL) << order);
}
@@ -1464,6 +1465,7 @@ void zone_init_free_lists(struct pglist_
bitmap_size = pages_to_bitmap_size(order, size);
zone->free_area[order].map =
(unsigned long *) alloc_bootmem_node(pgdat, bitmap_size);
+ zone->free_area[order].nr_free = 0;
}
}
@@ -1651,8 +1653,7 @@ static void frag_stop(struct seq_file *m
}
/*
- * This walks the freelist for each zone. Whilst this is slow, I'd rather
- * be slow here than slow down the fast path by keeping stats - mjbligh
+ * This walks the free areas for each zone.
*/
static int frag_show(struct seq_file *m, void *arg)
{
@@ -1668,14 +1669,8 @@ static int frag_show(struct seq_file *m,
spin_lock_irqsave(&zone->lock, flags);
seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
- for (order = 0; order < MAX_ORDER; ++order) {
- unsigned long nr_bufs = 0;
- struct list_head *elem;
-
- list_for_each(elem, &(zone->free_area[order].free_list))
- ++nr_bufs;
- seq_printf(m, "%6lu ", nr_bufs);
- }
+ for (order = 0; order < MAX_ORDER; ++order)
+ seq_printf(m, "%6lu ", zone->free_area[order].nr_free);
spin_unlock_irqrestore(&zone->lock, flags);
seq_putc(m, '\n');
}
_