summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorLi Haifeng <omycle@gmail.com>2012-09-17 14:09:21 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-09-17 15:00:38 -0700
commit0ba8f2d59304dfe69b59c034de723ad80f7ab9ac (patch)
treec6866a0514f55028499c473572dae48bd502f78f
parent8dcebaa9a0ae8a0487f4342f3d56d2cb1c980860 (diff)
downloadlinux-0ba8f2d59304dfe69b59c034de723ad80f7ab9ac.tar.bz2
mm/page_alloc: fix the page address of higher page's buddy calculation
The heuristic method for buddy has been introduced since commit 43506fad21ca ("mm/page_alloc.c: simplify calculation of combined index of adjacent buddy lists"). But the page address of higher page's buddy was wrongly calculated, which will lead page_is_buddy to fail for ever. IOW, the heuristic method would be disabled with the wrong page address of higher page's buddy. Calculating the page address of higher page's buddy should be based higher_page with the offset between index of higher page and index of higher page's buddy. Signed-off-by: Haifeng Li <omycle@gmail.com> Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: KyongHo Cho <pullip.cho@samsung.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Johannes Weiner <jweiner@redhat.com> Cc: <stable@vger.kernel.org> [2.6.38+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--mm/page_alloc.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index c66fb875104a..c13ea7538891 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -584,7 +584,7 @@ static inline void __free_one_page(struct page *page,
combined_idx = buddy_idx & page_idx;
higher_page = page + (combined_idx - page_idx);
buddy_idx = __find_buddy_index(combined_idx, order + 1);
- higher_buddy = page + (buddy_idx - combined_idx);
+ higher_buddy = higher_page + (buddy_idx - combined_idx);
if (page_is_buddy(higher_page, higher_buddy, order + 1)) {
list_add_tail(&page->lru,
&zone->free_area[order].free_list[migratetype]);