mm/page_alloc: batch the accounting updates in the bulk allocator

Now that the zone_statistics are simple counters that do not require
special protection, the bulk allocator accounting updates can be batch
updated without adding too much complexity with protected RMW updates or
using xchg.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Vlastimil Babka <[email protected]>
Acked-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Chuck Lever <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jesper Dangaard Brouer <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Sebastian Andrzej Siewior <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

1 files changed, 8 insertions, 0 deletions

diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h
index fe32a2210e73..d6a6cf53b127 100644
--- a/include/linux/vmstat.h
+++ b/include/linux/vmstat.h
@@ -247,6 +247,14 @@ __count_numa_event(struct zone *zone, enum numa_stat_item item)
 	raw_cpu_inc(pzstats->vm_numa_event[item]);
 }
 
+static inline void
+__count_numa_events(struct zone *zone, enum numa_stat_item item, long delta)
+{
+	struct per_cpu_zonestat __percpu *pzstats = zone->per_cpu_zonestats;
+
+	raw_cpu_add(pzstats->vm_numa_event[item], delta);
+}
+
 extern unsigned long sum_zone_node_page_state(int node,
 					      enum zone_stat_item item);
 extern unsigned long sum_zone_numa_event_state(int node, enum numa_stat_item item);