#endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
#if defined(CONFIG_TREE_RCU) || defined(CONFIG_TREE_PREEMPT_RCU)
-extern void rcutorture_record_test_transition(void);
-extern void rcutorture_record_progress(unsigned long vernum);
-extern void do_trace_rcu_torture_read(const char *rcutorturename,
- struct rcu_head *rhp,
- unsigned long secs,
- unsigned long c_old,
- unsigned long c);
+void rcutorture_record_test_transition(void);
+void rcutorture_record_progress(unsigned long vernum);
+void do_trace_rcu_torture_read(const char *rcutorturename,
+ struct rcu_head *rhp,
+ unsigned long secs,
+ unsigned long c_old,
+ unsigned long c);
#else
static inline void rcutorture_record_test_transition(void)
{
{
}
#ifdef CONFIG_RCU_TRACE
-extern void do_trace_rcu_torture_read(const char *rcutorturename,
- struct rcu_head *rhp,
- unsigned long secs,
- unsigned long c_old,
- unsigned long c);
+void do_trace_rcu_torture_read(const char *rcutorturename,
+ struct rcu_head *rhp,
+ unsigned long secs,
+ unsigned long c_old,
+ unsigned long c);
#else
#define do_trace_rcu_torture_read(rcutorturename, rhp, secs, c_old, c) \
do { } while (0)
* if CPU A and CPU B are the same CPU (but again only if the system has
* more than one CPU).
*/
-extern void call_rcu(struct rcu_head *head,
- void (*func)(struct rcu_head *head));
+void call_rcu(struct rcu_head *head,
+ void (*func)(struct rcu_head *head));
#else /* #ifdef CONFIG_PREEMPT_RCU */
* See the description of call_rcu() for more detailed information on
* memory ordering guarantees.
*/
-extern void call_rcu_bh(struct rcu_head *head,
- void (*func)(struct rcu_head *head));
+void call_rcu_bh(struct rcu_head *head,
+ void (*func)(struct rcu_head *head));
/**
* call_rcu_sched() - Queue an RCU for invocation after sched grace period.
* See the description of call_rcu() for more detailed information on
* memory ordering guarantees.
*/
-extern void call_rcu_sched(struct rcu_head *head,
- void (*func)(struct rcu_head *rcu));
+void call_rcu_sched(struct rcu_head *head,
+ void (*func)(struct rcu_head *rcu));
-extern void synchronize_sched(void);
+void synchronize_sched(void);
#ifdef CONFIG_PREEMPT_RCU
-extern void __rcu_read_lock(void);
-extern void __rcu_read_unlock(void);
-extern void rcu_read_unlock_special(struct task_struct *t);
+void __rcu_read_lock(void);
+void __rcu_read_unlock(void);
+void rcu_read_unlock_special(struct task_struct *t);
void synchronize_rcu(void);
/*
#endif /* #else #ifdef CONFIG_PREEMPT_RCU */
/* Internal to kernel */
-extern void rcu_init(void);
-extern void rcu_sched_qs(int cpu);
-extern void rcu_bh_qs(int cpu);
-extern void rcu_check_callbacks(int cpu, int user);
+void rcu_init(void);
+void rcu_sched_qs(int cpu);
+void rcu_bh_qs(int cpu);
+void rcu_check_callbacks(int cpu, int user);
struct notifier_block;
-extern void rcu_idle_enter(void);
-extern void rcu_idle_exit(void);
-extern void rcu_irq_enter(void);
-extern void rcu_irq_exit(void);
+void rcu_idle_enter(void);
+void rcu_idle_exit(void);
+void rcu_irq_enter(void);
+void rcu_irq_exit(void);
#ifdef CONFIG_RCU_USER_QS
-extern void rcu_user_enter(void);
-extern void rcu_user_exit(void);
+void rcu_user_enter(void);
+void rcu_user_exit(void);
#else
static inline void rcu_user_enter(void) { }
static inline void rcu_user_exit(void) { }
} while (0)
#if defined(CONFIG_DEBUG_LOCK_ALLOC) || defined(CONFIG_RCU_TRACE) || defined(CONFIG_SMP)
-extern bool __rcu_is_watching(void);
+bool __rcu_is_watching(void);
#endif /* #if defined(CONFIG_DEBUG_LOCK_ALLOC) || defined(CONFIG_RCU_TRACE) || defined(CONFIG_SMP) */
/*
* initialization.
*/
#ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD
-extern void init_rcu_head_on_stack(struct rcu_head *head);
-extern void destroy_rcu_head_on_stack(struct rcu_head *head);
+void init_rcu_head_on_stack(struct rcu_head *head);
+void destroy_rcu_head_on_stack(struct rcu_head *head);
#else /* !CONFIG_DEBUG_OBJECTS_RCU_HEAD */
static inline void init_rcu_head_on_stack(struct rcu_head *head)
{
extern struct lockdep_map rcu_lock_map;
extern struct lockdep_map rcu_bh_lock_map;
extern struct lockdep_map rcu_sched_lock_map;
+extern struct lockdep_map rcu_callback_map;
extern int debug_lockdep_rcu_enabled(void);
/**
* rcu_read_lock_bh_held() is defined out of line to avoid #include-file
* hell.
*/
-extern int rcu_read_lock_bh_held(void);
+int rcu_read_lock_bh_held(void);
/**
* rcu_read_lock_sched_held() - might we be in RCU-sched read-side critical section?
smp_read_barrier_depends(); \
(_________p1); \
})
-#define __rcu_assign_pointer(p, v, space) \
+
+/**
+ * RCU_INITIALIZER() - statically initialize an RCU-protected global variable
+ * @v: The value to statically initialize with.
+ */
+#define RCU_INITIALIZER(v) (typeof(*(v)) __force __rcu *)(v)
+
+/**
+ * rcu_assign_pointer() - assign to RCU-protected pointer
+ * @p: pointer to assign to
+ * @v: value to assign (publish)
+ *
+ * Assigns the specified value to the specified RCU-protected
+ * pointer, ensuring that any concurrent RCU readers will see
+ * any prior initialization.
+ *
+ * Inserts memory barriers on architectures that require them
+ * (which is most of them), and also prevents the compiler from
+ * reordering the code that initializes the structure after the pointer
+ * assignment. More importantly, this call documents which pointers
+ * will be dereferenced by RCU read-side code.
+ *
+ * In some special cases, you may use RCU_INIT_POINTER() instead
+ * of rcu_assign_pointer(). RCU_INIT_POINTER() is a bit faster due
+ * to the fact that it does not constrain either the CPU or the compiler.
+ * That said, using RCU_INIT_POINTER() when you should have used
+ * rcu_assign_pointer() is a very bad thing that results in
+ * impossible-to-diagnose memory corruption. So please be careful.
+ * See the RCU_INIT_POINTER() comment header for details.
+ *
+ * Note that rcu_assign_pointer() evaluates each of its arguments only
+ * once, appearances notwithstanding. One of the "extra" evaluations
+ * is in typeof() and the other visible only to sparse (__CHECKER__),
+ * neither of which actually execute the argument. As with most cpp
+ * macros, this execute-arguments-only-once property is important, so
+ * please be careful when making changes to rcu_assign_pointer() and the
+ * other macros that it invokes.
+ */
+#define rcu_assign_pointer(p, v) \
do { \
smp_wmb(); \
- (p) = (typeof(*v) __force space *)(v); \
+ ACCESS_ONCE(p) = RCU_INITIALIZER(v); \
} while (0)
preempt_enable_notrace();
}
-/**
- * rcu_assign_pointer() - assign to RCU-protected pointer
- * @p: pointer to assign to
- * @v: value to assign (publish)
- *
- * Assigns the specified value to the specified RCU-protected
- * pointer, ensuring that any concurrent RCU readers will see
- * any prior initialization.
- *
- * Inserts memory barriers on architectures that require them
- * (which is most of them), and also prevents the compiler from
- * reordering the code that initializes the structure after the pointer
- * assignment. More importantly, this call documents which pointers
- * will be dereferenced by RCU read-side code.
- *
- * In some special cases, you may use RCU_INIT_POINTER() instead
- * of rcu_assign_pointer(). RCU_INIT_POINTER() is a bit faster due
- * to the fact that it does not constrain either the CPU or the compiler.
- * That said, using RCU_INIT_POINTER() when you should have used
- * rcu_assign_pointer() is a very bad thing that results in
- * impossible-to-diagnose memory corruption. So please be careful.
- * See the RCU_INIT_POINTER() comment header for details.
- */
-#define rcu_assign_pointer(p, v) \
- __rcu_assign_pointer((p), (v), __rcu)
-
/**
* RCU_INIT_POINTER() - initialize an RCU protected pointer
*
*/
#define RCU_INIT_POINTER(p, v) \
do { \
- p = (typeof(*v) __force __rcu *)(v); \
+ p = RCU_INITIALIZER(v); \
} while (0)
/**
* GCC-style initialization for an RCU-protected pointer in a structure field.
*/
#define RCU_POINTER_INITIALIZER(p, v) \
- .p = (typeof(*v) __force __rcu *)(v)
+ .p = RCU_INITIALIZER(v)
/*
* Does the specified offset indicate that the corresponding rcu_head
__kfree_rcu(&((ptr)->rcu_head), offsetof(typeof(*(ptr)), rcu_head))
#ifdef CONFIG_RCU_NOCB_CPU
-extern bool rcu_is_nocb_cpu(int cpu);
+bool rcu_is_nocb_cpu(int cpu);
#else
static inline bool rcu_is_nocb_cpu(int cpu) { return false; }
#endif /* #else #ifdef CONFIG_RCU_NOCB_CPU */
/* Only for use by adaptive-ticks code. */
#ifdef CONFIG_NO_HZ_FULL_SYSIDLE
-extern bool rcu_sys_is_idle(void);
-extern void rcu_sysidle_force_exit(void);
+bool rcu_sys_is_idle(void);
+void rcu_sysidle_force_exit(void);
#else /* #ifdef CONFIG_NO_HZ_FULL_SYSIDLE */
static inline bool rcu_sys_is_idle(void)
projects / ~andy / linux / blobdiff