summaryrefslogtreecommitdiffstats
path: root/include/linux
diff options
context:
space:
mode:
authorHugh Dickins <hugh@veritas.com>2008-03-04 14:29:07 -0800
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2008-03-04 16:35:15 -0800
commit9442ec9df40d952b0de185ae5638a74970388e01 (patch)
tree14b06d71203be119d93736464ca49f37ce402c1c /include/linux
parent98837c7f82ef78aa38f40462aa2fcac68fd3acbf (diff)
downloadop-kernel-dev-9442ec9df40d952b0de185ae5638a74970388e01.zip
op-kernel-dev-9442ec9df40d952b0de185ae5638a74970388e01.tar.gz
memcg: bad page if page_cgroup when free
Replace free_hot_cold_page's VM_BUG_ON(page_get_page_cgroup(page)) by a "Bad page state" and clear: most users don't have CONFIG_DEBUG_VM on, and if it were set here, it'd likely cause corruption when the page is reused. Don't use page_assign_page_cgroup to clear it: that should be private to memcontrol.c, and always called with the lock taken; and memmap_init_zone doesn't need it either - like page->mapping and other pointers throughout the kernel, Linux assumes pointers in zeroed structures are NULL pointers. Instead use page_reset_bad_cgroup, added to memcontrol.h for this only. Signed-off-by: Hugh Dickins <hugh@veritas.com> Cc: David Rientjes <rientjes@google.com> Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Hirokazu Takahashi <taka@valinux.co.jp> Cc: YAMAMOTO Takashi <yamamoto@valinux.co.jp> Cc: Paul Menage <menage@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux')
-rw-r--r--include/linux/memcontrol.h8
1 files changed, 4 insertions, 4 deletions
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 56432ff..70789df 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -29,8 +29,9 @@ struct mm_struct;
extern void mm_init_cgroup(struct mm_struct *mm, struct task_struct *p);
extern void mm_free_cgroup(struct mm_struct *mm);
-extern void page_assign_page_cgroup(struct page *page,
- struct page_cgroup *pc);
+
+#define page_reset_bad_cgroup(page) ((page)->page_cgroup = 0)
+
extern struct page_cgroup *page_get_page_cgroup(struct page *page);
extern int mem_cgroup_charge(struct page *page, struct mm_struct *mm,
gfp_t gfp_mask);
@@ -82,8 +83,7 @@ static inline void mm_free_cgroup(struct mm_struct *mm)
{
}
-static inline void page_assign_page_cgroup(struct page *page,
- struct page_cgroup *pc)
+static inline void page_reset_bad_cgroup(struct page *page)
{
}
OpenPOWER on IntegriCloud