memcg: fix behavior under memory.limit equals to memsw.limit

[pandora-kernel.git] / mm / memcontrol.c

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index a83e039..6ceb6f2 100644 (file)
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -177,6 +177,9 @@ struct mem_cgroup {
 
        unsigned int    swappiness;
 
+       /* set when res.limit == memsw.limit */
+       bool            memsw_is_minimum;
+
        /*
         * statistics. This must be placed at the end of memcg.
         */
@@ -847,6 +850,10 @@ static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem,
        int ret, total = 0;
        int loop = 0;
 
+       /* If memsw_is_minimum==1, swap-out is of-no-use. */
+       if (root_mem->memsw_is_minimum)
+               noswap = true;
+
        while (loop < 2) {
                victim = mem_cgroup_select_victim(root_mem);
                if (victim == root_mem)
@@ -1752,6 +1759,12 @@ static int mem_cgroup_resize_limit(struct mem_cgroup *memcg,
                        break;
                }
                ret = res_counter_set_limit(&memcg->res, val);
+               if (!ret) {
+                       if (memswlimit == val)
+                               memcg->memsw_is_minimum = true;
+                       else
+                               memcg->memsw_is_minimum = false;
+               }
                mutex_unlock(&set_limit_mutex);
 
                if (!ret)
@@ -1799,6 +1812,12 @@ static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg,
                        break;
                }
                ret = res_counter_set_limit(&memcg->memsw, val);
+               if (!ret) {
+                       if (memlimit == val)
+                               memcg->memsw_is_minimum = true;
+                       else
+                               memcg->memsw_is_minimum = false;
+               }
                mutex_unlock(&set_limit_mutex);
 
                if (!ret)