Merge tag 'perf-urgent-for-mingo-5.1-20190419' of git://git.kernel.org/pub/scm/linux...

[linux-2.6-microblaze.git] / mm / memcontrol.c

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 532e0e2..81a0d39 100644 (file)
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3882,6 +3882,22 @@ struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb)
        return &memcg->cgwb_domain;
 }
 
+/*
+ * idx can be of type enum memcg_stat_item or node_stat_item.
+ * Keep in sync with memcg_exact_page().
+ */
+static unsigned long memcg_exact_page_state(struct mem_cgroup *memcg, int idx)
+{
+       long x = atomic_long_read(&memcg->stat[idx]);
+       int cpu;
+
+       for_each_online_cpu(cpu)
+               x += per_cpu_ptr(memcg->stat_cpu, cpu)->count[idx];
+       if (x < 0)
+               x = 0;
+       return x;
+}
+
 /**
  * mem_cgroup_wb_stats - retrieve writeback related stats from its memcg
  * @wb: bdi_writeback in question
@@ -3907,10 +3923,10 @@ void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages,
        struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css);
        struct mem_cgroup *parent;
 
-       *pdirty = memcg_page_state(memcg, NR_FILE_DIRTY);
+       *pdirty = memcg_exact_page_state(memcg, NR_FILE_DIRTY);
 
        /* this should eventually include NR_UNSTABLE_NFS */
-       *pwriteback = memcg_page_state(memcg, NR_WRITEBACK);
+       *pwriteback = memcg_exact_page_state(memcg, NR_WRITEBACK);
        *pfilepages = mem_cgroup_nr_lru_pages(memcg, (1 << LRU_INACTIVE_FILE) |
                                                     (1 << LRU_ACTIVE_FILE));
        *pheadroom = PAGE_COUNTER_MAX;