X-Git-Url: http://git.osdn.net/view?a=blobdiff_plain;f=kernel%2Fsched%2Ffair.c;h=f01eb276835d74e13fb24bc02920eb71c62b725f;hb=ae145f3c296b09548abddea97a21f9e984e0ccc9;hp=1eac0642fa86cf5cebcb2e3572e499b93045a8e8;hpb=a32f2cd759060ad2dd0a087177dfa108d48d2574;p=sagit-ice-cold%2Fkernel_xiaomi_msm8998.git

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 1eac0642fa86..f01eb276835d 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -2233,13 +2233,23 @@ no_join:
 	return;
 }
 
-void task_numa_free(struct task_struct *p)
+/*
+ * Get rid of NUMA staticstics associated with a task (either current or dead).
+ * If @final is set, the task is dead and has reached refcount zero, so we can
+ * safely free all relevant data structures. Otherwise, there might be
+ * concurrent reads from places like load balancing and procfs, and we should
+ * reset the data back to default state without freeing ->numa_faults.
+ */
+void task_numa_free(struct task_struct *p, bool final)
 {
 	struct numa_group *grp = p->numa_group;
-	void *numa_faults = p->numa_faults;
+	unsigned long *numa_faults = p->numa_faults;
 	unsigned long flags;
 	int i;
 
+	if (!numa_faults)
+		return;
+
 	if (grp) {
 		spin_lock_irqsave(&grp->lock, flags);
 		for (i = 0; i < NR_NUMA_HINT_FAULT_STATS * nr_node_ids; i++)
@@ -2252,8 +2262,14 @@ void task_numa_free(struct task_struct *p)
 		put_numa_group(grp);
 	}
 
-	p->numa_faults = NULL;
-	kfree(numa_faults);
+	if (final) {
+		p->numa_faults = NULL;
+		kfree(numa_faults);
+	} else {
+		p->total_numa_faults = 0;
+		for (i = 0; i < NR_NUMA_HINT_FAULT_STATS * nr_node_ids; i++)
+			numa_faults[i] = 0;
+	}
 }
 
 /*
@@ -10713,9 +10729,10 @@ no_move:
 out_balanced:
 	/*
 	 * We reach balance although we may have faced some affinity
-	 * constraints. Clear the imbalance flag if it was set.
+	 * constraints. Clear the imbalance flag only if other tasks got
+	 * a chance to move and fix the imbalance.
 	 */
-	if (sd_parent) {
+	if (sd_parent && !(env.flags & LBF_ALL_PINNED)) {
 		int *group_imbalance = &sd_parent->groups->sgc->imbalance;
 
 		if (*group_imbalance)