+void mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask,
+ int order)
+{
+ struct mem_cgroup *iter;
+ unsigned long chosen_points = 0;
+ unsigned long totalpages;
+ unsigned int points = 0;
+ struct task_struct *chosen = NULL;
+
+ /*
+ * If current has a pending SIGKILL, then automatically select it. The
+ * goal is to allow it to allocate so that it may quickly exit and free
+ * its memory.
+ */
+ if (fatal_signal_pending(current)) {
+ set_thread_flag(TIF_MEMDIE);
+ return;
+ }
+
+ check_panic_on_oom(CONSTRAINT_MEMCG, gfp_mask, order, NULL);
+ totalpages = mem_cgroup_get_limit(memcg) >> PAGE_SHIFT ? : 1;
+ for_each_mem_cgroup_tree(iter, memcg) {
+ struct cgroup *cgroup = iter->css.cgroup;
+ struct cgroup_iter it;
+ struct task_struct *task;
+
+ cgroup_iter_start(cgroup, &it);
+ while ((task = cgroup_iter_next(cgroup, &it))) {
+ switch (oom_scan_process_thread(task, totalpages, NULL,
+ false)) {
+ case OOM_SCAN_SELECT:
+ if (chosen)
+ put_task_struct(chosen);
+ chosen = task;
+ chosen_points = ULONG_MAX;
+ get_task_struct(chosen);
+ /* fall through */
+ case OOM_SCAN_CONTINUE:
+ continue;
+ case OOM_SCAN_ABORT:
+ cgroup_iter_end(cgroup, &it);
+ mem_cgroup_iter_break(memcg, iter);
+ if (chosen)
+ put_task_struct(chosen);
+ return;
+ case OOM_SCAN_OK:
+ break;
+ };
+ points = oom_badness(task, memcg, NULL, totalpages);
+ if (points > chosen_points) {
+ if (chosen)
+ put_task_struct(chosen);
+ chosen = task;
+ chosen_points = points;
+ get_task_struct(chosen);
+ }
+ }
+ cgroup_iter_end(cgroup, &it);
+ }
+
+ if (!chosen)
+ return;
+ points = chosen_points * 1000 / totalpages;
+ oom_kill_process(chosen, gfp_mask, order, points, totalpages, memcg,
+ NULL, "Memory cgroup out of memory");
+}
+