[patch 1/5] oom: don't kill unkillable children or siblings

Nick Piggin
2006-10-12T14:09:48Z

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>

Index: linux-2.6/mm/oom_kill.c
===================================================================
--- linux-2.6.orig/mm/oom_kill.c
+++ linux-2.6/mm/oom_kill.c
@@ -312,15 +312,24 @@ static int oom_kill_task(struct task_str
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;
}