The rmap walks in ksm.c are like those in rmap.c:
they can safely be done with anon_vma_lock_read().
Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx>
---
mm/ksm.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
--- 3.7+git/mm/ksm.c 2012-12-16 16:35:08.752441527 -0800
+++ linux/mm/ksm.c 2012-12-19 16:58:05.292145790 -0800
@@ -1624,7 +1624,7 @@ again:
struct anon_vma_chain *vmac;
struct vm_area_struct *vma;
- anon_vma_lock_write(anon_vma);
+ anon_vma_lock_read(anon_vma);
anon_vma_interval_tree_foreach(vmac, &anon_vma->rb_root,
0, ULONG_MAX) {
vma = vmac->vma;
@@ -1648,7 +1648,7 @@ again:
if (!search_new_forks || !mapcount)
break;
}
- anon_vma_unlock(anon_vma);
+ anon_vma_unlock_read(anon_vma);
if (!mapcount)
goto out;
}
@@ -1678,7 +1678,7 @@ again:
struct anon_vma_chain *vmac;
struct vm_area_struct *vma;
- anon_vma_lock_write(anon_vma);
+ anon_vma_lock_read(anon_vma);
anon_vma_interval_tree_foreach(vmac, &anon_vma->rb_root,
0, ULONG_MAX) {
vma = vmac->vma;
@@ -1697,11 +1697,11 @@ again:
ret = try_to_unmap_one(page, vma,
rmap_item->address, flags);
if (ret != SWAP_AGAIN || !page_mapped(page)) {
- anon_vma_unlock(anon_vma);
+ anon_vma_unlock_read(anon_vma);
goto out;
}
}
- anon_vma_unlock(anon_vma);
+ anon_vma_unlock_read(anon_vma);
}
if (!search_new_forks++)
goto again;
@@ -1731,7 +1731,7 @@ again:
struct anon_vma_chain *vmac;
struct vm_area_struct *vma;
- anon_vma_lock_write(anon_vma);
+ anon_vma_lock_read(anon_vma);
anon_vma_interval_tree_foreach(vmac, &anon_vma->rb_root,
0, ULONG_MAX) {
vma = vmac->vma;
@@ -1749,11 +1749,11 @@ again:
ret = rmap_one(page, vma, rmap_item->address, arg);
if (ret != SWAP_AGAIN) {
- anon_vma_unlock(anon_vma);
+ anon_vma_unlock_read(anon_vma);
goto out;
}
}
- anon_vma_unlock(anon_vma);
+ anon_vma_unlock_read(anon_vma);
}
if (!search_new_forks++)
goto again;
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>