net/mlx4_core: Fix when to save some qp context flags for dynamic VST to VGT transitions

[linux-2.6-block.git] / mm / rmap.c

diff --git a/mm/rmap.c b/mm/rmap.c
index 1ef36404e7b2d7daeef2061ff8f79524d7750bb9..91619fd709399a428a5a65fff6367d14cbef3db3 100644 (file)
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -141,14 +141,15 @@ static void anon_vma_chain_link(struct vm_area_struct *vma,
 }
 
 /**
- * anon_vma_prepare - attach an anon_vma to a memory region
+ * __anon_vma_prepare - attach an anon_vma to a memory region
  * @vma: the memory region in question
  *
  * This makes sure the memory mapping described by 'vma' has
  * an 'anon_vma' attached to it, so that we can associate the
  * anonymous pages mapped into it with that anon_vma.
  *
- * The common case will be that we already have one, but if
+ * The common case will be that we already have one, which
+ * is handled inline by anon_vma_prepare(). But if
  * not we either need to find an adjacent mapping that we
  * can re-use the anon_vma from (very common when the only
  * reason for splitting a vma has been mprotect()), or we
@@ -167,48 +168,46 @@ static void anon_vma_chain_link(struct vm_area_struct *vma,
  *
  * This must be called with the mmap_sem held for reading.
  */
-int anon_vma_prepare(struct vm_area_struct *vma)
+int __anon_vma_prepare(struct vm_area_struct *vma)
 {
-       struct anon_vma *anon_vma = vma->anon_vma;
+       struct mm_struct *mm = vma->vm_mm;
+       struct anon_vma *anon_vma, *allocated;
        struct anon_vma_chain *avc;
 
        might_sleep();
-       if (unlikely(!anon_vma)) {
-               struct mm_struct *mm = vma->vm_mm;
-               struct anon_vma *allocated;
 
-               avc = anon_vma_chain_alloc(GFP_KERNEL);
-               if (!avc)
-                       goto out_enomem;
+       avc = anon_vma_chain_alloc(GFP_KERNEL);
+       if (!avc)
+               goto out_enomem;
+
+       anon_vma = find_mergeable_anon_vma(vma);
+       allocated = NULL;
+       if (!anon_vma) {
+               anon_vma = anon_vma_alloc();
+               if (unlikely(!anon_vma))
+                       goto out_enomem_free_avc;
+               allocated = anon_vma;
+       }
 
-               anon_vma = find_mergeable_anon_vma(vma);
+       anon_vma_lock_write(anon_vma);
+       /* page_table_lock to protect against threads */
+       spin_lock(&mm->page_table_lock);
+       if (likely(!vma->anon_vma)) {
+               vma->anon_vma = anon_vma;
+               anon_vma_chain_link(vma, avc, anon_vma);
+               /* vma reference or self-parent link for new root */
+               anon_vma->degree++;
                allocated = NULL;
-               if (!anon_vma) {
-                       anon_vma = anon_vma_alloc();
-                       if (unlikely(!anon_vma))
-                               goto out_enomem_free_avc;
-                       allocated = anon_vma;
-               }
+               avc = NULL;
+       }
+       spin_unlock(&mm->page_table_lock);
+       anon_vma_unlock_write(anon_vma);
 
-               anon_vma_lock_write(anon_vma);
-               /* page_table_lock to protect against threads */
-               spin_lock(&mm->page_table_lock);
-               if (likely(!vma->anon_vma)) {
-                       vma->anon_vma = anon_vma;
-                       anon_vma_chain_link(vma, avc, anon_vma);
-                       /* vma reference or self-parent link for new root */
-                       anon_vma->degree++;
-                       allocated = NULL;
-                       avc = NULL;
-               }
-               spin_unlock(&mm->page_table_lock);
-               anon_vma_unlock_write(anon_vma);
+       if (unlikely(allocated))
+               put_anon_vma(allocated);
+       if (unlikely(avc))
+               anon_vma_chain_free(avc);
 
-               if (unlikely(allocated))
-                       put_anon_vma(allocated);
-               if (unlikely(avc))
-                       anon_vma_chain_free(avc);
-       }
        return 0;
 
  out_enomem_free_avc: