mm anon rmap: remove anon_vma_moveto_tail

[karo-tx-linux.git] / mm / mremap.c

diff --git a/mm/mremap.c b/mm/mremap.c
index cc06d0e48d050dc0a2ec47cf62fd8d3b22b4a2be..5588bb6e92956c049932baac68826fbaa6ce4a24 100644 (file)
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -74,6 +74,7 @@ static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd,
                unsigned long new_addr)
 {
        struct address_space *mapping = NULL;
+       struct anon_vma *anon_vma = vma->anon_vma;
        struct mm_struct *mm = vma->vm_mm;
        pte_t *old_pte, *new_pte, pte;
        spinlock_t *old_ptl, *new_ptl;
@@ -88,6 +89,8 @@ static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd,
                mapping = vma->vm_file->f_mapping;
                mutex_lock(&mapping->i_mmap_mutex);
        }
+       if (anon_vma)
+               anon_vma_lock(anon_vma);
 
        /*
         * We don't have to worry about the ordering of src and dst
@@ -114,6 +117,8 @@ static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd,
                spin_unlock(new_ptl);
        pte_unmap(new_pte - 1);
        pte_unmap_unlock(old_pte - 1, old_ptl);
+       if (anon_vma)
+               anon_vma_unlock(anon_vma);
        if (mapping)
                mutex_unlock(&mapping->i_mmap_mutex);
 }
@@ -220,15 +225,6 @@ static unsigned long move_vma(struct vm_area_struct *vma,
 
        moved_len = move_page_tables(vma, old_addr, new_vma, new_addr, old_len);
        if (moved_len < old_len) {
-               /*
-                * Before moving the page tables from the new vma to
-                * the old vma, we need to be sure the old vma is
-                * queued after new vma in the same_anon_vma list to
-                * prevent SMP races with rmap_walk (that could lead
-                * rmap_walk to miss some page table).
-                */
-               anon_vma_moveto_tail(vma);
-
                /*
                 * On error, move entries back from new area to old,
                 * which will succeed since page tables still there,