Merge branch 'sched/rt' into sched/core, to pick up -rt changes

Pick up the first couple of patches working towards PREEMPT_RT.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

include/linux/blk-cgroup.h

@@ -181,6 +181,7 @@ struct blkcg_policy {
 
 extern struct blkcg blkcg_root;
 extern struct cgroup_subsys_state * const blkcg_root_css;
+extern bool blkcg_debug_stats;
 
 struct blkcg_gq *blkg_lookup_slowpath(struct blkcg *blkcg,
 				      struct request_queue *q, bool update_hint);

include/linux/blk_types.h

@@ -311,6 +311,7 @@ enum req_flag_bits {
 	__REQ_RAHEAD,		/* read ahead, can fail anytime */
 	__REQ_BACKGROUND,	/* background IO */
 	__REQ_NOWAIT,           /* Don't wait if request will block */
+	__REQ_NOWAIT_INLINE,	/* Return would-block error inline */
 	/*
 	 * When a shared kthread needs to issue a bio for a cgroup, doing
 	 * so synchronously can lead to priority inversions as the kthread
@@ -345,6 +346,7 @@ enum req_flag_bits {
 #define REQ_RAHEAD		(1ULL << __REQ_RAHEAD)
 #define REQ_BACKGROUND		(1ULL << __REQ_BACKGROUND)
 #define REQ_NOWAIT		(1ULL << __REQ_NOWAIT)
+#define REQ_NOWAIT_INLINE	(1ULL << __REQ_NOWAIT_INLINE)
 #define REQ_CGROUP_PUNT		(1ULL << __REQ_CGROUP_PUNT)
 
 #define REQ_NOUNMAP		(1ULL << __REQ_NOUNMAP)
@@ -418,12 +420,13 @@ static inline int op_stat_group(unsigned int op)
 
 typedef unsigned int blk_qc_t;
 #define BLK_QC_T_NONE		-1U
+#define BLK_QC_T_EAGAIN		-2U
 #define BLK_QC_T_SHIFT		16
 #define BLK_QC_T_INTERNAL	(1U << 31)
 
 static inline bool blk_qc_t_valid(blk_qc_t cookie)
 {
-	return cookie != BLK_QC_T_NONE;
+	return cookie != BLK_QC_T_NONE && cookie != BLK_QC_T_EAGAIN;
 }
 
 static inline unsigned int blk_qc_t_to_queue_num(blk_qc_t cookie)

include/linux/cred.h

@@ -145,7 +145,11 @@ struct cred {
 	struct user_struct *user;	/* real user ID subscription */
 	struct user_namespace *user_ns; /* user_ns the caps and keyrings are relative to. */
 	struct group_info *group_info;	/* supplementary groups for euid/fsgid */
-	struct rcu_head	rcu;		/* RCU deletion hook */
+	/* RCU deletion */
+	union {
+		int non_rcu;			/* Can we skip RCU deletion? */
+		struct rcu_head	rcu;		/* RCU deletion hook */
+	};
 } __randomize_layout;
 
 extern void __put_cred(struct cred *);
@@ -246,6 +250,7 @@ static inline const struct cred *get_cred(const struct cred *cred)
 	if (!cred)
 		return cred;
 	validate_creds(cred);
+	nonconst_cred->non_rcu = 0;
 	return get_new_cred(nonconst_cred);
 }
 
@@ -257,6 +262,7 @@ static inline const struct cred *get_cred_rcu(const struct cred *cred)
 	if (!atomic_inc_not_zero(&nonconst_cred->usage))
 		return NULL;
 	validate_creds(cred);
+	nonconst_cred->non_rcu = 0;
 	return cred;
 }
 

include/linux/device.h

@@ -915,6 +915,8 @@ struct dev_links_info {
  * 		This identifies the device type and carries type-specific
  * 		information.
  * @mutex:	Mutex to synchronize calls to its driver.
+ * @lockdep_mutex: An optional debug lock that a subsystem can use as a
+ * 		peer lock to gain localized lockdep coverage of the device_lock.
  * @bus:	Type of bus device is on.
  * @driver:	Which driver has allocated this
  * @platform_data: Platform data specific to the device.
@@ -998,6 +1000,9 @@ struct device {
 					   core doesn't touch it */
 	void		*driver_data;	/* Driver data, set and get with
 					   dev_set_drvdata/dev_get_drvdata */
+#ifdef CONFIG_PROVE_LOCKING
+	struct mutex		lockdep_mutex;
+#endif
 	struct mutex		mutex;	/* mutex to synchronize calls to
 					 * its driver.
 					 */
@@ -1383,6 +1388,7 @@ extern int (*platform_notify_remove)(struct device *dev);
  */
 extern struct device *get_device(struct device *dev);
 extern void put_device(struct device *dev);
+extern bool kill_device(struct device *dev);
 
 #ifdef CONFIG_DEVTMPFS
 extern int devtmpfs_create_node(struct device *dev);

include/linux/dma-mapping.h

@@ -689,8 +689,8 @@ static inline int dma_coerce_mask_and_coherent(struct device *dev, u64 mask)
  */
 static inline bool dma_addressing_limited(struct device *dev)
 {
-	return min_not_zero(*dev->dma_mask, dev->bus_dma_mask) <
-		dma_get_required_mask(dev);
+	return min_not_zero(dma_get_mask(dev), dev->bus_dma_mask) <
+			    dma_get_required_mask(dev);
 }
 
 #ifdef CONFIG_ARCH_HAS_SETUP_DMA_OPS

include/linux/elevator.h

@@ -45,7 +45,6 @@ struct elevator_mq_ops {
 	struct request *(*dispatch_request)(struct blk_mq_hw_ctx *);
 	bool (*has_work)(struct blk_mq_hw_ctx *);
 	void (*completed_request)(struct request *, u64);
-	void (*started_request)(struct request *);
 	void (*requeue_request)(struct request *);
 	struct request *(*former_request)(struct request_queue *, struct request *);
 	struct request *(*next_request)(struct request_queue *, struct request *);

include/linux/iova.h

@@ -155,6 +155,7 @@ struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
 void copy_reserved_iova(struct iova_domain *from, struct iova_domain *to);
 void init_iova_domain(struct iova_domain *iovad, unsigned long granule,
 	unsigned long start_pfn);
+bool has_iova_flush_queue(struct iova_domain *iovad);
 int init_iova_flush_queue(struct iova_domain *iovad,
 			  iova_flush_cb flush_cb, iova_entry_dtor entry_dtor);
 struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
@@ -235,6 +236,11 @@ static inline void init_iova_domain(struct iova_domain *iovad,
 {
 }
 
+static inline bool has_iova_flush_queue(struct iova_domain *iovad)
+{
+	return false;
+}
+
 static inline int init_iova_flush_queue(struct iova_domain *iovad,
 					iova_flush_cb flush_cb,
 					iova_entry_dtor entry_dtor)

include/linux/mod_devicetable.h

@@ -814,6 +814,7 @@ struct tee_client_device_id {
 /**
  * struct wmi_device_id - WMI device identifier
  * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
+ * @context: pointer to driver specific data
  */
 struct wmi_device_id {
 	const char guid_string[UUID_STRING_LEN+1];

include/linux/of.h

@@ -1164,7 +1164,7 @@ static inline int of_property_read_string_index(const struct device_node *np,
 }
 
 /**
- * of_property_read_bool - Findfrom a property
+ * of_property_read_bool - Find a property
  * @np:		device node from which the property value is to be read.
  * @propname:	name of the property to be searched.
  *

include/linux/preempt.h

@@ -182,7 +182,7 @@ do { \
 
 #define preemptible()	(preempt_count() == 0 && !irqs_disabled())
 
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
 #define preempt_enable() \
 do { \
 	barrier(); \
@@ -203,7 +203,7 @@ do { \
 		__preempt_schedule(); \
 } while (0)
 
-#else /* !CONFIG_PREEMPT */
+#else /* !CONFIG_PREEMPTION */
 #define preempt_enable() \
 do { \
 	barrier(); \
@@ -217,7 +217,7 @@ do { \
 } while (0)
 
 #define preempt_check_resched() do { } while (0)
-#endif /* CONFIG_PREEMPT */
+#endif /* CONFIG_PREEMPTION */
 
 #define preempt_disable_notrace() \
 do { \

include/linux/rcupdate.h

@@ -578,7 +578,7 @@ do {									      \
  *
  * In non-preemptible RCU implementations (TREE_RCU and TINY_RCU),
  * it is illegal to block while in an RCU read-side critical section.
- * In preemptible RCU implementations (PREEMPT_RCU) in CONFIG_PREEMPT
+ * In preemptible RCU implementations (PREEMPT_RCU) in CONFIG_PREEMPTION
  * kernel builds, RCU read-side critical sections may be preempted,
  * but explicit blocking is illegal.  Finally, in preemptible RCU
  * implementations in real-time (with -rt patchset) kernel builds, RCU

include/linux/rcutree.h

@@ -53,7 +53,7 @@ void rcu_scheduler_starting(void);
 extern int rcu_scheduler_active __read_mostly;
 void rcu_end_inkernel_boot(void);
 bool rcu_is_watching(void);
-#ifndef CONFIG_PREEMPT
+#ifndef CONFIG_PREEMPTION
 void rcu_all_qs(void);
 #endif
 

include/linux/sched.h

@@ -1772,7 +1772,7 @@ static inline int test_tsk_need_resched(struct task_struct *tsk)
  * value indicates whether a reschedule was done in fact.
  * cond_resched_lock() will drop the spinlock before scheduling,
  */
-#ifndef CONFIG_PREEMPT
+#ifndef CONFIG_PREEMPTION
 extern int _cond_resched(void);
 #else
 static inline int _cond_resched(void) { return 0; }
@@ -1801,12 +1801,12 @@ static inline void cond_resched_rcu(void)
 
 /*
  * Does a critical section need to be broken due to another
- * task waiting?: (technically does not depend on CONFIG_PREEMPT,
+ * task waiting?: (technically does not depend on CONFIG_PREEMPTION,
  * but a general need for low latency)
  */
 static inline int spin_needbreak(spinlock_t *lock)
 {
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
 	return spin_is_contended(lock);
 #else
 	return 0;

include/linux/spinlock.h

@@ -214,7 +214,7 @@ static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
 
 /*
  * Define the various spin_lock methods.  Note we define these
- * regardless of whether CONFIG_SMP or CONFIG_PREEMPT are set. The
+ * regardless of whether CONFIG_SMP or CONFIG_PREEMPTION are set. The
  * various methods are defined as nops in the case they are not
  * required.
  */

include/linux/spinlock_api_smp.h

@@ -96,7 +96,7 @@ static inline int __raw_spin_trylock(raw_spinlock_t *lock)
 
 /*
  * If lockdep is enabled then we use the non-preemption spin-ops
- * even on CONFIG_PREEMPT, because lockdep assumes that interrupts are
+ * even on CONFIG_PREEMPTION, because lockdep assumes that interrupts are
  * not re-enabled during lock-acquire (which the preempt-spin-ops do):
  */
 #if !defined(CONFIG_GENERIC_LOCKBREAK) || defined(CONFIG_DEBUG_LOCK_ALLOC)

include/linux/torture.h

@@ -86,7 +86,7 @@ void _torture_stop_kthread(char *m, struct task_struct **tp);
 #define torture_stop_kthread(n, tp) \
 	_torture_stop_kthread("Stopping " #n " task", &(tp))
 
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
 #define torture_preempt_schedule() preempt_schedule()
 #else
 #define torture_preempt_schedule()

include/linux/wait.h

@@ -126,6 +126,19 @@ static inline int waitqueue_active(struct wait_queue_head *wq_head)
 	return !list_empty(&wq_head->head);
 }
 
+/**
+ * wq_has_single_sleeper - check if there is only one sleeper
+ * @wq_head: wait queue head
+ *
+ * Returns true of wq_head has only one sleeper on the list.
+ *
+ * Please refer to the comment for waitqueue_active.
+ */
+static inline bool wq_has_single_sleeper(struct wait_queue_head *wq_head)
+{
+	return list_is_singular(&wq_head->head);
+}
+
 /**
  * wq_has_sleeper - check if there are any waiting processes
  * @wq_head: wait queue head