mm/page_alloc: when handling percpu_pagelist_fraction, don't unneedly recalulate high

Simply moves calculation of the new 'high' value outside the
for_each_possible_cpu() loop, as it does not depend on the cpu.

Signed-off-by: Cody P Schafer <[email protected]>
Cc: Gilad Ben-Yossef <[email protected]>
Cc: KOSAKI Motohiro <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Pekka Enberg <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 8125263..386de0f 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5575,7 +5575,6 @@
  * cpu.  It is the fraction of total pages in each zone that a hot per cpu pagelist
  * can have before it gets flushed back to buddy allocator.
  */
-
 int percpu_pagelist_fraction_sysctl_handler(ctl_table *table, int write,
 	void __user *buffer, size_t *length, loff_t *ppos)
 {
@@ -5589,12 +5588,11 @@
 
 	mutex_lock(&pcp_batch_high_lock);
 	for_each_populated_zone(zone) {
-		for_each_possible_cpu(cpu) {
-			unsigned long  high;
-			high = zone->managed_pages / percpu_pagelist_fraction;
+		unsigned long  high;
+		high = zone->managed_pages / percpu_pagelist_fraction;
+		for_each_possible_cpu(cpu)
 			setup_pagelist_highmark(
-				per_cpu_ptr(zone->pageset, cpu), high);
-		}
+					per_cpu_ptr(zone->pageset, cpu), high);
 	}
 	mutex_unlock(&pcp_batch_high_lock);
 	return 0;