alinux: mm: oom_kill: show killed task's cgroup info in global oom

Some users want to know the killed task's cgroup info in global
oom, this message would help them to make upper decision.
Signed-off-by: NWenwei Tao <wenwei.tao@linux.alibaba.com>
Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>

mm/oom_kill.c

@@ -451,6 +451,11 @@ static void dump_header(struct oom_control *oc, struct task_struct *p)
 	if (is_memcg_oom(oc))
 		mem_cgroup_print_oom_info(oc->memcg, p);
 	else {
+#ifdef CONFIG_MEMCG
+		pr_info("Task in ");
+		pr_cont_cgroup_path(task_cgroup(p, memory_cgrp_id));
+		pr_cont(" killed as a result of limit of host\n");
+#endif
 		show_mem(SHOW_MEM_FILTER_NODES, oc->nodemask);
 		if (is_dump_unreclaim_slabs())
 			dump_unreclaimable_slab();