[PATCH] page_alloc.c: inline __rmqueue()

[Aaron Lu]

__rmqueue() is called by rmqueue_bulk() and rmqueue() under zone->lock
and that lock can be heavily contended with memory intensive applications.

Since __rmqueue() is a small function, inline it can save us some time.
With the will-it-scale/page_fault1/process benchmark, when using nr_cpu
processes to stress buddy:

On a 2 sockets Intel-Skylake machine:
      base          %change       head
     77342            +6.3%      82203        will-it-scale.per_process_ops

On a 4 sockets Intel-Skylake machine:
      base          %change       head
     75746            +4.6%      79248        will-it-scale.per_process_ops

This patch adds inline to __rmqueue().

Signed-off-by: Aaron Lu <aaron.lu@xxxxxxxxx>
---
 mm/page_alloc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 0e309ce4a44a..c9605c7ebaf6 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2291,7 +2291,7 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype)
  * Do the hard work of removing an element from the buddy allocator.
  * Call me with the zone->lock already held.
  */
-static struct page *__rmqueue(struct zone *zone, unsigned int order,
+static inline struct page *__rmqueue(struct zone *zone, unsigned int order,
 				int migratetype)
 {
 	struct page *page;
-- 
2.13.6