mm: replace __get_cpu_var uses with this_cpu_ptr

Replace places where __get_cpu_var() is used for an address calculation
with this_cpu_ptr().

Signed-off-by: Christoph Lameter <cl@linux.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index a4317da..b9b8e82 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -1623,7 +1623,7 @@
 	 * 1000+ tasks, all of them start dirtying pages at exactly the same
 	 * time, hence all honoured too large initial task->nr_dirtied_pause.
 	 */
-	p =  &__get_cpu_var(bdp_ratelimits);
+	p =  this_cpu_ptr(&bdp_ratelimits);
 	if (unlikely(current->nr_dirtied >= ratelimit))
 		*p = 0;
 	else if (unlikely(*p >= ratelimit_pages)) {
@@ -1635,7 +1635,7 @@
 	 * short-lived tasks (eg. gcc invocations in a kernel build) escaping
 	 * the dirty throttling and livelock other long-run dirtiers.
 	 */
-	p = &__get_cpu_var(dirty_throttle_leaks);
+	p = this_cpu_ptr(&dirty_throttle_leaks);
 	if (*p > 0 && current->nr_dirtied < ratelimit) {
 		unsigned long nr_pages_dirtied;
 		nr_pages_dirtied = min(*p, ratelimit - current->nr_dirtied);