dect
/
linux-2.6
Archived
13
0
Fork 0

hugetlb: pull gigantic page initialisation out of the default path

As we can determine exactly when a gigantic page is in use we can optimise
the common regular page cases by pulling out gigantic page initialisation
into its own function.  As gigantic pages are never released to buddy we
do not need a destructor.  This effectivly reverts the previous change to
the main buddy allocator.  It also adds a paranoid check to ensure we
never release gigantic pages from hugetlbfs to the main buddy.

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Cc: Jon Tollefson <kniht@linux.vnet.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: <stable@kernel.org>		[2.6.27.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Andy Whitcroft 2008-11-06 12:53:27 -08:00 committed by Linus Torvalds
parent 69d177c2fc
commit 18229df5b6
3 changed files with 34 additions and 9 deletions

View File

@ -491,6 +491,8 @@ static void update_and_free_page(struct hstate *h, struct page *page)
{
int i;
VM_BUG_ON(h->order >= MAX_ORDER);
h->nr_huge_pages--;
h->nr_huge_pages_node[page_to_nid(page)]--;
for (i = 0; i < pages_per_huge_page(h); i++) {
@ -1005,6 +1007,14 @@ found:
return 1;
}
static void prep_compound_huge_page(struct page *page, int order)
{
if (unlikely(order > (MAX_ORDER - 1)))
prep_compound_gigantic_page(page, order);
else
prep_compound_page(page, order);
}
/* Put bootmem huge pages into the standard lists after mem_map is up */
static void __init gather_bootmem_prealloc(void)
{
@ -1015,7 +1025,7 @@ static void __init gather_bootmem_prealloc(void)
struct hstate *h = m->hstate;
__ClearPageReserved(page);
WARN_ON(page_count(page) != 1);
prep_compound_page(page, h->order);
prep_compound_huge_page(page, h->order);
prep_new_huge_page(h, page, page_to_nid(page));
}
}

View File

@ -17,6 +17,7 @@ void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
unsigned long floor, unsigned long ceiling);
extern void prep_compound_page(struct page *page, unsigned long order);
extern void prep_compound_gigantic_page(struct page *page, unsigned long order);
static inline void set_page_count(struct page *page, int v)
{

View File

@ -263,34 +263,48 @@ void prep_compound_page(struct page *page, unsigned long order)
{
int i;
int nr_pages = 1 << order;
struct page *p = page + 1;
set_compound_page_dtor(page, free_compound_page);
set_compound_order(page, order);
__SetPageHead(page);
for (i = 1; i < nr_pages; i++, p++) {
if (unlikely((i & (MAX_ORDER_NR_PAGES - 1)) == 0))
p = pfn_to_page(page_to_pfn(page) + i);
for (i = 1; i < nr_pages; i++) {
struct page *p = page + i;
__SetPageTail(p);
p->first_page = page;
}
}
static void destroy_compound_page(struct page *page, unsigned long order)
#ifdef CONFIG_HUGETLBFS
void prep_compound_gigantic_page(struct page *page, unsigned long order)
{
int i;
int nr_pages = 1 << order;
struct page *p = page + 1;
set_compound_page_dtor(page, free_compound_page);
set_compound_order(page, order);
__SetPageHead(page);
for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) {
__SetPageTail(p);
p->first_page = page;
}
}
#endif
static void destroy_compound_page(struct page *page, unsigned long order)
{
int i;
int nr_pages = 1 << order;
if (unlikely(compound_order(page) != order))
bad_page(page);
if (unlikely(!PageHead(page)))
bad_page(page);
__ClearPageHead(page);
for (i = 1; i < nr_pages; i++, p++) {
if (unlikely((i & (MAX_ORDER_NR_PAGES - 1)) == 0))
p = pfn_to_page(page_to_pfn(page) + i);
for (i = 1; i < nr_pages; i++) {
struct page *p = page + i;
if (unlikely(!PageTail(p) |
(p->first_page != page)))