mm: change direct call of spin_lock(anon_vma->lock) to inline function

Subsitute a direct call of spin_lock(anon_vma->lock) with an inline
function doing exactly the same.

This makes it easier to do the substitution to the root anon_vma lock in a
following patch.

We will deal with the handful of special locks (nested, dec_and_lock, etc)
separately.

Signed-off-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tested-by: Larry Woodman <lwoodman@redhat.com>
Acked-by: Larry Woodman <lwoodman@redhat.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/ksm.c b/mm/ksm.c
index 6c3e99b..eb9f680 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -327,7 +327,7 @@
 
 	if (atomic_dec_and_lock(&anon_vma->external_refcount, &anon_vma->lock)) {
 		int empty = list_empty(&anon_vma->head);
-		spin_unlock(&anon_vma->lock);
+		anon_vma_unlock(anon_vma);
 		if (empty)
 			anon_vma_free(anon_vma);
 	}
@@ -1566,7 +1566,7 @@
 		struct anon_vma_chain *vmac;
 		struct vm_area_struct *vma;
 
-		spin_lock(&anon_vma->lock);
+		anon_vma_lock(anon_vma);
 		list_for_each_entry(vmac, &anon_vma->head, same_anon_vma) {
 			vma = vmac->vma;
 			if (rmap_item->address < vma->vm_start ||
@@ -1589,7 +1589,7 @@
 			if (!search_new_forks || !mapcount)
 				break;
 		}
-		spin_unlock(&anon_vma->lock);
+		anon_vma_unlock(anon_vma);
 		if (!mapcount)
 			goto out;
 	}
@@ -1619,7 +1619,7 @@
 		struct anon_vma_chain *vmac;
 		struct vm_area_struct *vma;
 
-		spin_lock(&anon_vma->lock);
+		anon_vma_lock(anon_vma);
 		list_for_each_entry(vmac, &anon_vma->head, same_anon_vma) {
 			vma = vmac->vma;
 			if (rmap_item->address < vma->vm_start ||
@@ -1637,11 +1637,11 @@
 			ret = try_to_unmap_one(page, vma,
 					rmap_item->address, flags);
 			if (ret != SWAP_AGAIN || !page_mapped(page)) {
-				spin_unlock(&anon_vma->lock);
+				anon_vma_unlock(anon_vma);
 				goto out;
 			}
 		}
-		spin_unlock(&anon_vma->lock);
+		anon_vma_unlock(anon_vma);
 	}
 	if (!search_new_forks++)
 		goto again;
@@ -1671,7 +1671,7 @@
 		struct anon_vma_chain *vmac;
 		struct vm_area_struct *vma;
 
-		spin_lock(&anon_vma->lock);
+		anon_vma_lock(anon_vma);
 		list_for_each_entry(vmac, &anon_vma->head, same_anon_vma) {
 			vma = vmac->vma;
 			if (rmap_item->address < vma->vm_start ||
@@ -1688,11 +1688,11 @@
 
 			ret = rmap_one(page, vma, rmap_item->address, arg);
 			if (ret != SWAP_AGAIN) {
-				spin_unlock(&anon_vma->lock);
+				anon_vma_unlock(anon_vma);
 				goto out;
 			}
 		}
-		spin_unlock(&anon_vma->lock);
+		anon_vma_unlock(anon_vma);
 	}
 	if (!search_new_forks++)
 		goto again;