[PATCH 4/6] mm,oom: exclude oom_task_origin processes if they are OOM-unkillable.

[Tetsuo Handa]

>From 4924ca3031444bfb831b2d4f004e5a613ad48d68 Mon Sep 17 00:00:00 2001
From: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
Date: Wed, 17 Feb 2016 16:35:12 +0900
Subject: [PATCH 4/6] mm,oom: exclude oom_task_origin processes if they are OOM-unkillable.

oom_scan_process_thread() returns OOM_SCAN_SELECT when there is a
thread which returns oom_task_origin() == true. But it is possible
that that thread is marked as OOM-unkillable.

This patch changes oom_scan_process_thread() not to select it
if it is marked as OOM-unkillable.

Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
---
 mm/oom_kill.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index b0c327d..ebc6764 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -308,7 +308,8 @@ enum oom_scan_t oom_scan_process_thread(struct oom_control *oc,
 	 * If task is allocating a lot of memory and has been marked to be
 	 * killed first if it triggers an oom, then select it.
 	 */
-	if (oom_task_origin(task) && !test_tsk_thread_flag(task, TIF_MEMDIE))
+	if (oom_task_origin(task) && !test_tsk_thread_flag(task, TIF_MEMDIE) &&
+	    task->signal->oom_score_adj != OOM_SCORE_ADJ_MIN)
 		return OOM_SCAN_SELECT;
 
 	return OOM_SCAN_OK;
-- 
1.8.3.1