memcg, oom: notify on oom killer invocation from the charge path

[sfrench/cifs-2.6.git] / mm / memcontrol.c

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 6e1469b80cb7d57d3cdf01ef9c917a21ece0b7fa..af7f18b32389e4ec0435128aa4b6d93fac6b80ca 100644 (file)
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1293,32 +1293,39 @@ static const char *const memcg1_stat_names[] = {
 
 #define K(x) ((x) << (PAGE_SHIFT-10))
 /**
- * mem_cgroup_print_oom_info: Print OOM information relevant to memory controller.
+ * mem_cgroup_print_oom_context: Print OOM information relevant to
+ * memory controller.
  * @memcg: The memory cgroup that went over limit
  * @p: Task that is going to be killed
  *
  * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is
  * enabled
  */
-void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p)
+void mem_cgroup_print_oom_context(struct mem_cgroup *memcg, struct task_struct *p)
 {
-       struct mem_cgroup *iter;
-       unsigned int i;
-
        rcu_read_lock();
 
+       if (memcg) {
+               pr_cont(",oom_memcg=");
+               pr_cont_cgroup_path(memcg->css.cgroup);
+       } else
+               pr_cont(",global_oom");
        if (p) {
-               pr_info("Task in ");
+               pr_cont(",task_memcg=");
                pr_cont_cgroup_path(task_cgroup(p, memory_cgrp_id));
-               pr_cont(" killed as a result of limit of ");
-       } else {
-               pr_info("Memory limit reached of cgroup ");
        }
-
-       pr_cont_cgroup_path(memcg->css.cgroup);
-       pr_cont("\n");
-
        rcu_read_unlock();
+}
+
+/**
+ * mem_cgroup_print_oom_meminfo: Print OOM memory information relevant to
+ * memory controller.
+ * @memcg: The memory cgroup that went over limit
+ */
+void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg)
+{
+       struct mem_cgroup *iter;
+       unsigned int i;
 
        pr_info("memory: usage %llukB, limit %llukB, failcnt %lu\n",
                K((u64)page_counter_read(&memcg->memory)),
@@ -1666,6 +1673,9 @@ enum oom_status {
 
 static enum oom_status mem_cgroup_oom(struct mem_cgroup *memcg, gfp_t mask, int order)
 {
+       enum oom_status ret;
+       bool locked;
+
        if (order > PAGE_ALLOC_COSTLY_ORDER)
                return OOM_SKIPPED;
 
@@ -1700,10 +1710,23 @@ static enum oom_status mem_cgroup_oom(struct mem_cgroup *memcg, gfp_t mask, int
                return OOM_ASYNC;
        }
 
+       mem_cgroup_mark_under_oom(memcg);
+
+       locked = mem_cgroup_oom_trylock(memcg);
+
+       if (locked)
+               mem_cgroup_oom_notify(memcg);
+
+       mem_cgroup_unmark_under_oom(memcg);
        if (mem_cgroup_out_of_memory(memcg, mask, order))
-               return OOM_SUCCESS;
+               ret = OOM_SUCCESS;
+       else
+               ret = OOM_FAILED;
 
-       return OOM_FAILED;
+       if (locked)
+               mem_cgroup_oom_unlock(memcg);
+
+       return ret;
 }
 
 /**