---

yaml
---
r: 7423
b: refs/heads/master
c: ef08e3b
h: refs/heads/master
i:
  7421: 8643f6f
  7419: bc0d691
  7415: 102f3bc
  7407: 4071ce0
  7391: f6f16c1
  7359: b1984f2
  7295: 94638a8
  7167: 4561ccd
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 9bf2229f8817677127a60c177aefce1badd22d7b
+refs/heads/master: ef08e3b4981aebf2ba9bd7025ef7210e8eec07ce

trunk/include/linux/cpuset.h

@@ -24,6 +24,7 @@ void cpuset_update_current_mems_allowed(void);
 void cpuset_restrict_to_mems_allowed(unsigned long *nodes);
 int cpuset_zonelist_valid_mems_allowed(struct zonelist *zl);
 extern int cpuset_zone_allowed(struct zone *z, unsigned int __nocast gfp_mask);
+extern int cpuset_excl_nodes_overlap(const struct task_struct *p);
 extern struct file_operations proc_cpuset_operations;
 extern char *cpuset_task_status_allowed(struct task_struct *task, char *buffer);
 
@@ -54,6 +55,11 @@ static inline int cpuset_zone_allowed(struct zone *z,
 	return 1;
 }
 
+static inline int cpuset_excl_nodes_overlap(const struct task_struct *p)
+{
+	return 1;
+}
+
 static inline char *cpuset_task_status_allowed(struct task_struct *task,
 							char *buffer)
 {

trunk/kernel/cpuset.c

@@ -1688,6 +1688,39 @@ int cpuset_zone_allowed(struct zone *z, unsigned int __nocast gfp_mask)
 	return allowed;
 }
 
+/**
+ * cpuset_excl_nodes_overlap - Do we overlap @p's mem_exclusive ancestors?
+ * @p: pointer to task_struct of some other task.
+ *
+ * Description: Return true if the nearest mem_exclusive ancestor
+ * cpusets of tasks @p and current overlap.  Used by oom killer to
+ * determine if task @p's memory usage might impact the memory
+ * available to the current task.
+ *
+ * Acquires cpuset_sem - not suitable for calling from a fast path.
+ **/
+
+int cpuset_excl_nodes_overlap(const struct task_struct *p)
+{
+	const struct cpuset *cs1, *cs2;	/* my and p's cpuset ancestors */
+	int overlap = 0;		/* do cpusets overlap? */
+
+	down(&cpuset_sem);
+	cs1 = current->cpuset;
+	if (!cs1)
+		goto done;		/* current task exiting */
+	cs2 = p->cpuset;
+	if (!cs2)
+		goto done;		/* task p is exiting */
+	cs1 = nearest_exclusive_ancestor(cs1);
+	cs2 = nearest_exclusive_ancestor(cs2);
+	overlap = nodes_intersects(cs1->mems_allowed, cs2->mems_allowed);
+done:
+	up(&cpuset_sem);
+
+	return overlap;
+}
+
 /*
  * proc_cpuset_show()
  *  - Print tasks cpuset path into seq_file.

trunk/mm/oom_kill.c

@@ -20,6 +20,7 @@
 #include <linux/swap.h>
 #include <linux/timex.h>
 #include <linux/jiffies.h>
+#include <linux/cpuset.h>
 
 /* #define DEBUG */
 
@@ -152,6 +153,10 @@ static struct task_struct * select_bad_process(void)
 			continue;
 		if (p->oomkilladj == OOM_DISABLE)
 			continue;
+		/* If p's nodes don't overlap ours, it won't help to kill p. */
+		if (!cpuset_excl_nodes_overlap(p))
+			continue;
+
 		/*
 		 * This is in the process of releasing memory so for wait it
 		 * to finish before killing some other task by mistake.