path: root/mm/sparse.c
diff options
authorAndrea Arcangeli <aarcange@redhat.com>2011-01-13 15:47:00 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2011-01-13 17:32:43 -0800
commit5f24ce5fd34c3ca1b3d10d30da754732da64d5c0 (patch)
treec82d27461f2adda210e77808b7dd04eaec017f2f /mm/sparse.c
parent21ae5b01750f14140809508a478a4413792e0261 (diff)
thp: remove PG_buddy
PG_buddy can be converted to _mapcount == -2. So the PG_compound_lock can be added to page->flags without overflowing (because of the sparse section bits increasing) with CONFIG_X86_PAE=y and CONFIG_X86_PAT=y. This also has to move the memory hotplug code from _mapcount to lru.next to avoid any risk of clashes. We can't use lru.next for PG_buddy removal, but memory hotplug can use lru.next even more easily than the mapcount instead. Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/sparse.c')
1 files changed, 2 insertions, 2 deletions
diff --git a/mm/sparse.c b/mm/sparse.c
index 95ac219af37..93250207c5c 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -671,10 +671,10 @@ static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages)
static void free_map_bootmem(struct page *page, unsigned long nr_pages)
unsigned long maps_section_nr, removing_section_nr, i;
- int magic;
+ unsigned long magic;
for (i = 0; i < nr_pages; i++, page++) {
- magic = atomic_read(&page->_mapcount);
+ magic = (unsigned long) page->lru.next;
BUG_ON(magic == NODE_INFO);