mm: remove rest of ACCESS_ONCE() usages

We converted some of the usages of ACCESS_ONCE to READ_ONCE in the mm/
tree since it doesn't work reliably on non-scalar types.

This patch removes the rest of the usages of ACCESS_ONCE, and use the new
READ_ONCE API for the read accesses.  This makes things cleaner, instead
of using separate/multiple sets of APIs.

Signed-off-by: Jason Low <jason.low2@hp.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Davidlohr Bueso <dave@stgolabs.net>
Acked-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 4 deletions

diff --git a/mm/mmap.c b/mm/mmap.c
index 06a6076c92e5..e65cbe0d64fc 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1133,7 +1133,7 @@ static int anon_vma_compatible(struct vm_area_struct *a, struct vm_area_struct *
  * by another page fault trying to merge _that_. But that's ok: if it
  * is being set up, that automatically means that it will be a singleton
  * acceptable for merging, so we can do all of this optimistically. But
- * we do that ACCESS_ONCE() to make sure that we never re-load the pointer.
+ * we do that READ_ONCE() to make sure that we never re-load the pointer.
  *
  * IOW: that the "list_is_singular()" test on the anon_vma_chain only
  * matters for the 'stable anon_vma' case (ie the thing we want to avoid
@@ -1147,7 +1147,7 @@ static int anon_vma_compatible(struct vm_area_struct *a, struct vm_area_struct *
 static struct anon_vma *reusable_anon_vma(struct vm_area_struct *old, struct vm_area_struct *a, struct vm_area_struct *b)
 {
         if (anon_vma_compatible(a, b)) {
-                struct anon_vma *anon_vma = ACCESS_ONCE(old->anon_vma);
+                struct anon_vma *anon_vma = READ_ONCE(old->anon_vma);
 
                 if (anon_vma && list_is_singular(&old->anon_vma_chain))
                         return anon_vma;
@@ -2100,7 +2100,7 @@ static int acct_stack_growth(struct vm_area_struct *vma, unsigned long size, uns
         actual_size = size;
         if (size && (vma->vm_flags & (VM_GROWSUP | VM_GROWSDOWN)))
                 actual_size -= PAGE_SIZE;
-        if (actual_size > ACCESS_ONCE(rlim[RLIMIT_STACK].rlim_cur))
+        if (actual_size > READ_ONCE(rlim[RLIMIT_STACK].rlim_cur))
                 return -ENOMEM;
 
         /* mlock limit tests */
@@ -2108,7 +2108,7 @@ static int acct_stack_growth(struct vm_area_struct *vma, unsigned long size, uns
                 unsigned long locked;
                 unsigned long limit;
                 locked = mm->locked_vm + grow;
-                limit = ACCESS_ONCE(rlim[RLIMIT_MEMLOCK].rlim_cur);
+                limit = READ_ONCE(rlim[RLIMIT_MEMLOCK].rlim_cur);
                 limit >>= PAGE_SHIFT;
                 if (locked > limit && !capable(CAP_IPC_LOCK))
                         return -ENOMEM;