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

Pull scheduler updates from Ingo Molnar:
 "The main changes in this cycle are:

   - 'Nested Sleep Debugging', activated when CONFIG_DEBUG_ATOMIC_SLEEP=y.

     This instruments might_sleep() checks to catch places that nest
     blocking primitives - such as mutex usage in a wait loop.  Such
     bugs can result in hard to debug races/hangs.

     Another category of invalid nesting that this facility will detect
     is the calling of blocking functions from within schedule() ->
     sched_submit_work() -> blk_schedule_flush_plug().

     There's some potential for false positives (if secondary blocking
     primitives themselves are not ready yet for this facility), but the
     kernel will warn once about such bugs per bootup, so the warning
     isn't much of a nuisance.

     This feature comes with a number of fixes, for problems uncovered
     with it, so no messages are expected normally.

   - Another round of sched/numa optimizations and refinements, for
     CONFIG_NUMA_BALANCING=y.

   - Another round of sched/dl fixes and refinements.

  Plus various smaller fixes and cleanups"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
  sched: Add missing rcu protection to wake_up_all_idle_cpus
  sched/deadline: Introduce start_hrtick_dl() for !CONFIG_SCHED_HRTICK
  sched/numa: Init numa balancing fields of init_task
  sched/deadline: Remove unnecessary definitions in cpudeadline.h
  sched/cpupri: Remove unnecessary definitions in cpupri.h
  sched/deadline: Fix rq->dl.pushable_tasks bug in push_dl_task()
  sched/fair: Fix stale overloaded status in the busiest group finding logic
  sched: Move p->nr_cpus_allowed check to select_task_rq()
  sched/completion: Document when to use wait_for_completion_io_*()
  sched: Update comments about CLONE_NEWUTS and CLONE_NEWIPC
  sched/fair: Kill task_struct::numa_entry and numa_group::task_list
  sched: Refactor task_struct to use numa_faults instead of numa_* pointers
  sched/deadline: Don't check CONFIG_SMP in switched_from_dl()
  sched/deadline: Reschedule from switched_from_dl() after a successful pull
  sched/deadline: Push task away if the deadline is equal to curr during wakeup
  sched/deadline: Add deadline rq status print
  sched/deadline: Fix artificial overrun introduced by yield_task_dl()
  sched/rt: Clean up check_preempt_equal_prio()
  sched/core: Use dl_bw_of() under rcu_read_lock_sched()
  sched: Check if we got a shallowest_idle_cpu before searching for least_loaded_cpu
  ...

1 files changed, 79 insertions, 1 deletions

diff --git a/include/linux/wait.h b/include/linux/wait.h
index e4a8eb9312ea..2232ed16635a 100644
--- a/include/linux/wait.h
+++ b/include/linux/wait.h
@@ -13,9 +13,12 @@ typedef struct __wait_queue wait_queue_t;
 typedef int (*wait_queue_func_t)(wait_queue_t *wait, unsigned mode, int flags, void *key);
 int default_wake_function(wait_queue_t *wait, unsigned mode, int flags, void *key);
 
+/* __wait_queue::flags */
+#define WQ_FLAG_EXCLUSIVE	0x01
+#define WQ_FLAG_WOKEN		0x02
+
 struct __wait_queue {
 	unsigned int		flags;
-#define WQ_FLAG_EXCLUSIVE	0x01
 	void			*private;
 	wait_queue_func_t	func;
 	struct list_head	task_list;
@@ -258,11 +261,37 @@ __out:	__ret;								\
  */
 #define wait_event(wq, condition)					\
 do {									\
+	might_sleep();							\
 	if (condition)							\
 		break;							\
 	__wait_event(wq, condition);					\
 } while (0)
 
+#define __wait_event_freezable(wq, condition)				\
+	___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0,		\
+			    schedule(); try_to_freeze())
+
+/**
+ * wait_event - sleep (or freeze) until a condition gets true
+ * @wq: the waitqueue to wait on
+ * @condition: a C expression for the event to wait for
+ *
+ * The process is put to sleep (TASK_INTERRUPTIBLE -- so as not to contribute
+ * to system load) until the @condition evaluates to true. The
+ * @condition is checked each time the waitqueue @wq is woken up.
+ *
+ * wake_up() has to be called after changing any variable that could
+ * change the result of the wait condition.
+ */
+#define wait_event_freezable(wq, condition)				\
+({									\
+	int __ret = 0;							\
+	might_sleep();							\
+	if (!(condition))						\
+		__ret = __wait_event_freezable(wq, condition);		\
+	__ret;								\
+})
+
 #define __wait_event_timeout(wq, condition, timeout)			\
 	___wait_event(wq, ___wait_cond_timeout(condition),		\
 		      TASK_UNINTERRUPTIBLE, 0, timeout,			\
@@ -290,11 +319,30 @@ do {									\
 #define wait_event_timeout(wq, condition, timeout)			\
 ({									\
 	long __ret = timeout;						\
+	might_sleep();							\
 	if (!___wait_cond_timeout(condition))				\
 		__ret = __wait_event_timeout(wq, condition, timeout);	\
 	__ret;								\
 })
 
+#define __wait_event_freezable_timeout(wq, condition, timeout)		\
+	___wait_event(wq, ___wait_cond_timeout(condition),		\
+		      TASK_INTERRUPTIBLE, 0, timeout,			\
+		      __ret = schedule_timeout(__ret); try_to_freeze())
+
+/*
+ * like wait_event_timeout() -- except it uses TASK_INTERRUPTIBLE to avoid
+ * increasing load and is freezable.
+ */
+#define wait_event_freezable_timeout(wq, condition, timeout)		\
+({									\
+	long __ret = timeout;						\
+	might_sleep();							\
+	if (!___wait_cond_timeout(condition))				\
+		__ret = __wait_event_freezable_timeout(wq, condition, timeout);	\
+	__ret;								\
+})
+
 #define __wait_event_cmd(wq, condition, cmd1, cmd2)			\
 	(void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, 0,	\
 			    cmd1; schedule(); cmd2)
@@ -315,6 +363,7 @@ do {									\
  */
 #define wait_event_cmd(wq, condition, cmd1, cmd2)			\
 do {									\
+	might_sleep();							\
 	if (condition)							\
 		break;							\
 	__wait_event_cmd(wq, condition, cmd1, cmd2);			\
@@ -342,6 +391,7 @@ do {									\
 #define wait_event_interruptible(wq, condition)				\
 ({									\
 	int __ret = 0;							\
+	might_sleep();							\
 	if (!(condition))						\
 		__ret = __wait_event_interruptible(wq, condition);	\
 	__ret;								\
@@ -375,6 +425,7 @@ do {									\
 #define wait_event_interruptible_timeout(wq, condition, timeout)	\
 ({									\
 	long __ret = timeout;						\
+	might_sleep();							\
 	if (!___wait_cond_timeout(condition))				\
 		__ret = __wait_event_interruptible_timeout(wq,		\
 						condition, timeout);	\
@@ -425,6 +476,7 @@ do {									\
 #define wait_event_hrtimeout(wq, condition, timeout)			\
 ({									\
 	int __ret = 0;							\
+	might_sleep();							\
 	if (!(condition))						\
 		__ret = __wait_event_hrtimeout(wq, condition, timeout,	\
 					       TASK_UNINTERRUPTIBLE);	\
@@ -450,6 +502,7 @@ do {									\
 #define wait_event_interruptible_hrtimeout(wq, condition, timeout)	\
 ({									\
 	long __ret = 0;							\
+	might_sleep();							\
 	if (!(condition))						\
 		__ret = __wait_event_hrtimeout(wq, condition, timeout,	\
 					       TASK_INTERRUPTIBLE);	\
@@ -463,12 +516,27 @@ do {									\
 #define wait_event_interruptible_exclusive(wq, condition)		\
 ({									\
 	int __ret = 0;							\
+	might_sleep();							\
 	if (!(condition))						\
 		__ret = __wait_event_interruptible_exclusive(wq, condition);\
 	__ret;								\
 })
 
 
+#define __wait_event_freezable_exclusive(wq, condition)			\
+	___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, 0,		\
+			schedule(); try_to_freeze())
+
+#define wait_event_freezable_exclusive(wq, condition)			\
+({									\
+	int __ret = 0;							\
+	might_sleep();							\
+	if (!(condition))						\
+		__ret = __wait_event_freezable_exclusive(wq, condition);\
+	__ret;								\
+})
+
+
 #define __wait_event_interruptible_locked(wq, condition, exclusive, irq) \
 ({									\
 	int __ret = 0;							\
@@ -637,6 +705,7 @@ do {									\
 #define wait_event_killable(wq, condition)				\
 ({									\
 	int __ret = 0;							\
+	might_sleep();							\
 	if (!(condition))						\
 		__ret = __wait_event_killable(wq, condition);		\
 	__ret;								\
@@ -830,6 +899,8 @@ void prepare_to_wait_exclusive(wait_queue_head_t *q, wait_queue_t *wait, int sta
 long prepare_to_wait_event(wait_queue_head_t *q, wait_queue_t *wait, int state);
 void finish_wait(wait_queue_head_t *q, wait_queue_t *wait);
 void abort_exclusive_wait(wait_queue_head_t *q, wait_queue_t *wait, unsigned int mode, void *key);
+long wait_woken(wait_queue_t *wait, unsigned mode, long timeout);
+int woken_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key);
 int autoremove_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key);
 int wake_bit_function(wait_queue_t *wait, unsigned mode, int sync, void *key);
 
@@ -886,6 +957,7 @@ extern int bit_wait_io_timeout(struct wait_bit_key *);
 static inline int
 wait_on_bit(void *word, int bit, unsigned mode)
 {
+	might_sleep();
 	if (!test_bit(bit, word))
 		return 0;
 	return out_of_line_wait_on_bit(word, bit,
@@ -910,6 +982,7 @@ wait_on_bit(void *word, int bit, unsigned mode)
 static inline int
 wait_on_bit_io(void *word, int bit, unsigned mode)
 {
+	might_sleep();
 	if (!test_bit(bit, word))
 		return 0;
 	return out_of_line_wait_on_bit(word, bit,
@@ -936,6 +1009,7 @@ wait_on_bit_io(void *word, int bit, unsigned mode)
 static inline int
 wait_on_bit_action(void *word, int bit, wait_bit_action_f *action, unsigned mode)
 {
+	might_sleep();
 	if (!test_bit(bit, word))
 		return 0;
 	return out_of_line_wait_on_bit(word, bit, action, mode);
@@ -963,6 +1037,7 @@ wait_on_bit_action(void *word, int bit, wait_bit_action_f *action, unsigned mode
 static inline int
 wait_on_bit_lock(void *word, int bit, unsigned mode)
 {
+	might_sleep();
 	if (!test_and_set_bit(bit, word))
 		return 0;
 	return out_of_line_wait_on_bit_lock(word, bit, bit_wait, mode);
@@ -986,6 +1061,7 @@ wait_on_bit_lock(void *word, int bit, unsigned mode)
 static inline int
 wait_on_bit_lock_io(void *word, int bit, unsigned mode)
 {
+	might_sleep();
 	if (!test_and_set_bit(bit, word))
 		return 0;
 	return out_of_line_wait_on_bit_lock(word, bit, bit_wait_io, mode);
@@ -1011,6 +1087,7 @@ wait_on_bit_lock_io(void *word, int bit, unsigned mode)
 static inline int
 wait_on_bit_lock_action(void *word, int bit, wait_bit_action_f *action, unsigned mode)
 {
+	might_sleep();
 	if (!test_and_set_bit(bit, word))
 		return 0;
 	return out_of_line_wait_on_bit_lock(word, bit, action, mode);
@@ -1029,6 +1106,7 @@ wait_on_bit_lock_action(void *word, int bit, wait_bit_action_f *action, unsigned
 static inline
 int wait_on_atomic_t(atomic_t *val, int (*action)(atomic_t *), unsigned mode)
 {
+	might_sleep();
 	if (atomic_read(val) == 0)
 		return 0;
 	return out_of_line_wait_on_atomic_t(val, action, mode);