From: Nick Piggin <npiggin@suse.de>
Date: Thu, 7 Dec 2006 04:31:50 +0000 (-0800)
Subject: [PATCH] oom: don't kill unkillable children or siblings
X-Git-Tag: v2.6.20-rc1~145^2^2~353
X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=c33e0fca3508f0aa387b1c10d0ef158102deb140;p=linux-2.6-omap-h63xx.git

[PATCH] oom: don't kill unkillable children or siblings

Abort the kill if any of our threads have OOM_DISABLE set.  Having this
test here also prevents any OOM_DISABLE child of the "selected" process
from being killed.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index 2e3ce3a928b..bc2627deb7f 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -313,15 +313,24 @@ static int oom_kill_task(struct task_struct *p, const char *message)
 	if (mm == NULL)
 		return 1;
 
+	/*
+	 * Don't kill the process if any threads are set to OOM_DISABLE
+	 */
+	do_each_thread(g, q) {
+		if (q->mm == mm && p->oomkilladj == OOM_DISABLE)
+			return 1;
+	} while_each_thread(g, q);
+
 	__oom_kill_task(p, message);
+
 	/*
 	 * kill all processes that share the ->mm (i.e. all threads),
 	 * but are in a different thread group
 	 */
-	do_each_thread(g, q)
+	do_each_thread(g, q) {
 		if (q->mm == mm && q->tgid != p->tgid)
 			__oom_kill_task(q, message);
-	while_each_thread(g, q);
+	} while_each_thread(g, q);
 
 	return 0;
 }