path: root/mm/ksm.c
diff options
authorHugh Dickins <hugh.dickins@tiscali.co.uk>2009-09-21 17:02:26 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-09-22 07:17:33 -0700
commita913e182ab9484308e870af37a14d372742d53b0 (patch)
tree0fca5598aeba4c53999ec46b6b82b46f9a981965 /mm/ksm.c
parentksm: remove VM_MERGEABLE_FLAGS (diff)
ksm: clean up obsolete references
A few cleanups, given the munlock fix: the comment on ksm_test_exit() no longer applies, and it can be made private to ksm.c; there's no more reference to mmu_gather or tlb.h, and mmap.c doesn't need ksm.h. Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk> Acked-by: Izik Eidus <ieidus@redhat.com> Cc: 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/ksm.c')
1 files changed, 13 insertions, 1 deletions
diff --git a/mm/ksm.c b/mm/ksm.c
index 3bd54ce9eb38..e11e7a5ac84f 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -32,7 +32,6 @@
#include <linux/mmu_notifier.h>
#include <linux/ksm.h>
-#include <asm/tlb.h>
#include <asm/tlbflush.h>
@@ -285,6 +284,19 @@ static inline int in_stable_tree(struct rmap_item *rmap_item)
+ * ksmd, and unmerge_and_remove_all_rmap_items(), must not touch an mm's
+ * page tables after it has passed through ksm_exit() - which, if necessary,
+ * takes mmap_sem briefly to serialize against them. ksm_exit() does not set
+ * a special flag: they can just back out as soon as mm_users goes to zero.
+ * ksm_test_exit() is used throughout to make this test for exit: in some
+ * places for correctness, in some places just to avoid unnecessary work.
+ */
+static inline bool ksm_test_exit(struct mm_struct *mm)
+ return atomic_read(&mm->mm_users) == 0;
* We use break_ksm to break COW on a ksm page: it's a stripped down
* if (get_user_pages(current, mm, addr, 1, 1, 1, &page, NULL) == 1)