Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Fix lockup by limiting load-balance retries on lock-break
  sched: Fix CONFIG_CGROUP_SCHED dependency
  sched: Remove empty #ifdefs

2 files changed, 7 insertions, 10 deletions

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index cecbb64be05f..fd7b25e90079 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7134,10 +7134,6 @@ void set_curr_task(int cpu, struct task_struct *p)
 
 #endif
 
-#ifdef CONFIG_RT_GROUP_SCHED
-#else /* !CONFIG_RT_GROUP_SCHED */
-#endif /* CONFIG_RT_GROUP_SCHED */
-
 #ifdef CONFIG_CGROUP_SCHED
 /* task_group_lock serializes the addition/removal of task groups */
 static DEFINE_SPINLOCK(task_group_lock);
@@ -7246,9 +7242,6 @@ void sched_move_task(struct task_struct *tsk)
 }
 #endif /* CONFIG_CGROUP_SCHED */
 
-#ifdef CONFIG_FAIR_GROUP_SCHED
-#endif
-
 #if defined(CONFIG_RT_GROUP_SCHED) || defined(CONFIG_CFS_BANDWIDTH)
 static unsigned long to_ratio(u64 period, u64 runtime)
 {
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 8e42de9105f8..84adb2d66cbd 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -3130,8 +3130,10 @@ task_hot(struct task_struct *p, u64 now, struct sched_domain *sd)
 }
 
 #define LBF_ALL_PINNED  0x01
-#define LBF_NEED_BREAK  0x02
-#define LBF_ABORT       0x04
+#define LBF_NEED_BREAK  0x02    /* clears into HAD_BREAK */
+#define LBF_HAD_BREAK   0x04
+#define LBF_HAD_BREAKS  0x0C    /* count HAD_BREAKs overflows into ABORT */
+#define LBF_ABORT       0x10
 
 /*
  * can_migrate_task - may task p from runqueue rq be migrated to this_cpu?
@@ -4508,7 +4510,9 @@ redo:
                         goto out_balanced;
 
                 if (lb_flags & LBF_NEED_BREAK) {
-                        lb_flags &= ~LBF_NEED_BREAK;
+                        lb_flags += LBF_HAD_BREAK - LBF_NEED_BREAK;
+                        if (lb_flags & LBF_ABORT)
+                                goto out_balanced;
                         goto redo;
                 }