Add a BUG() check to __free_pages_ok() - to catch someone freeing a
page which has a non-zero refcount. Actually, this check is mainly to
catch someone (ie: shrink_cache()) incrementing a page's refcount
shortly after it has been freed
Also clean up __free_pages_ok() a bit and convert lots of BUGs to BUG_ON.
page_alloc.c | 80 ++++++++++++++++++++++-------------------------------------
1 files changed, 30 insertions(+), 50 deletions(-)
--- 2.5.24/mm/page_alloc.c~free-pages-check Thu Jul 4 16:17:33 2002
+++ 2.5.24-akpm/mm/page_alloc.c Thu Jul 4 16:17:33 2002
@@ -86,23 +86,24 @@ static void __free_pages_ok (struct page
struct page *base;
zone_t *zone;
- if (PagePrivate(page))
- BUG();
- if (page->mapping)
- BUG();
- if (PageLocked(page))
- BUG();
- if (PageLRU(page))
- BUG();
- if (PageActive(page))
- BUG();
- if (PageWriteback(page))
- BUG();
- ClearPageDirty(page);
-
- if (current->flags & PF_FREE_PAGES)
- goto local_freelist;
- back_local_freelist:
+ BUG_ON(PagePrivate(page));
+ BUG_ON(page->mapping != NULL);
+ BUG_ON(PageLocked(page));
+ BUG_ON(PageLRU(page));
+ BUG_ON(PageActive(page));
+ BUG_ON(PageWriteback(page));
+ if (PageDirty(page))
+ ClearPageDirty(page);
+ BUG_ON(page_count(page) != 0);
+
+ if (unlikely(current->flags & PF_FREE_PAGES)) {
+ if (!current->nr_local_pages && !in_interrupt()) {
+ list_add(&page->list, ¤t->local_pages);
+ page->index = order;
+ current->nr_local_pages++;
+ goto out;
+ }
+ }
zone = page_zone(page);
@@ -112,18 +113,14 @@ static void __free_pages_ok (struct page
if (page_idx & ~mask)
BUG();
index = page_idx >> (1 + order);
-
area = zone->free_area + order;
spin_lock_irqsave(&zone->lock, flags);
-
zone->free_pages -= mask;
-
while (mask + (1 << (MAX_ORDER-1))) {
struct page *buddy1, *buddy2;
- if (area >= zone->free_area + MAX_ORDER)
- BUG();
+ BUG_ON(area >= zone->free_area + MAX_ORDER);
if (!__test_and_change_bit(index, area->map))
/*
* the buddy page is still allocated.
@@ -136,11 +133,8 @@ static void __free_pages_ok (struct page
*/
buddy1 = base + (page_idx ^ -mask);
buddy2 = base + page_idx;
- if (bad_range(zone, buddy1))
- BUG();
- if (bad_range(zone, buddy2))
- BUG();
-
+ BUG_ON(bad_range(zone, buddy1));
+ BUG_ON(bad_range(zone, buddy2));
list_del(&buddy1->list);
mask <<= 1;
area++;
@@ -148,19 +142,9 @@ static void __free_pages_ok (struct page
page_idx &= mask;
}
list_add(&(base + page_idx)->list, &area->free_list);
-
spin_unlock_irqrestore(&zone->lock, flags);
+out:
return;
-
- local_freelist:
- if (current->nr_local_pages)
- goto back_local_freelist;
- if (in_interrupt())
- goto back_local_freelist;
-
- list_add(&page->list, ¤t->local_pages);
- page->index = order;
- current->nr_local_pages++;
}
#define MARK_USED(index, order, area) \
@@ -172,8 +156,7 @@ static inline struct page * expand (zone
unsigned long size = 1 << high;
while (high > low) {
- if (bad_range(zone, page))
- BUG();
+ BUG_ON(bad_range(zone, page));
area--;
high--;
size >>= 1;
@@ -182,8 +165,7 @@ static inline struct page * expand (zone
index += size;
page += size;
}
- if (bad_range(zone, page))
- BUG();
+ BUG_ON(bad_range(zone, page));
return page;
}
@@ -223,8 +205,7 @@ static struct page * rmqueue(zone_t *zon
unsigned int index;
page = list_entry(curr, struct page, list);
- if (bad_range(zone, page))
- BUG();
+ BUG_ON(bad_range(zone, page));
list_del(curr);
index = page - zone->zone_mem_map;
if (curr_order != MAX_ORDER-1)
@@ -279,14 +260,14 @@ struct page *_alloc_pages(unsigned int g
}
#endif
-static struct page * FASTCALL(balance_classzone(zone_t *, unsigned int, unsigned int, int *));
-static struct page * balance_classzone(zone_t * classzone, unsigned int gfp_mask, unsigned int order, int * freed)
+static /* inline */ struct page *
+balance_classzone(zone_t * classzone, unsigned int gfp_mask,
+ unsigned int order, int * freed)
{
struct page * page = NULL;
int __freed = 0;
- if (in_interrupt())
- BUG();
+ BUG_ON(in_interrupt());
current->allocation_order = order;
current->flags |= PF_MEMALLOC | PF_FREE_PAGES;
@@ -793,8 +774,7 @@ void __init free_area_init_core(int nid,
unsigned long totalpages, offset, realtotalpages;
const unsigned long zone_required_alignment = 1UL << (MAX_ORDER-1);
- if (zone_start_paddr & ~PAGE_MASK)
- BUG();
+ BUG_ON(zone_start_paddr & ~PAGE_MASK);
totalpages = 0;
for (i = 0; i < MAX_NR_ZONES; i++) {
-
-
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This archive was generated by hypermail 2b29 : Sun Jul 07 2002 - 22:00:14 EST