Initial import

1 files changed, 429 insertions, 0 deletions

diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h
new file mode 100644
index 000000000..3e18379df
--- /dev/null
+++ b/include/linux/spinlock.h
@@ -0,0 +1,429 @@
+#ifndef __LINUX_SPINLOCK_H
+#define __LINUX_SPINLOCK_H
+
+/*
+ * include/linux/spinlock.h - generic spinlock/rwlock declarations
+ *
+ * here's the role of the various spinlock/rwlock related include files:
+ *
+ * on SMP builds:
+ *
+ *  asm/spinlock_types.h: contains the arch_spinlock_t/arch_rwlock_t and the
+ *                        initializers
+ *
+ *  linux/spinlock_types.h:
+ *                        defines the generic type and initializers
+ *
+ *  asm/spinlock.h:       contains the arch_spin_*()/etc. lowlevel
+ *                        implementations, mostly inline assembly code
+ *
+ *   (also included on UP-debug builds:)
+ *
+ *  linux/spinlock_api_smp.h:
+ *                        contains the prototypes for the _spin_*() APIs.
+ *
+ *  linux/spinlock.h:     builds the final spin_*() APIs.
+ *
+ * on UP builds:
+ *
+ *  linux/spinlock_type_up.h:
+ *                        contains the generic, simplified UP spinlock type.
+ *                        (which is an empty structure on non-debug builds)
+ *
+ *  linux/spinlock_types.h:
+ *                        defines the generic type and initializers
+ *
+ *  linux/spinlock_up.h:
+ *                        contains the arch_spin_*()/etc. version of UP
+ *                        builds. (which are NOPs on non-debug, non-preempt
+ *                        builds)
+ *
+ *   (included on UP-non-debug builds:)
+ *
+ *  linux/spinlock_api_up.h:
+ *                        builds the _spin_*() APIs.
+ *
+ *  linux/spinlock.h:     builds the final spin_*() APIs.
+ */
+
+#include <linux/typecheck.h>
+#include <linux/preempt.h>
+#include <linux/linkage.h>
+#include <linux/compiler.h>
+#include <linux/irqflags.h>
+#include <linux/thread_info.h>
+#include <linux/kernel.h>
+#include <linux/stringify.h>
+#include <linux/bottom_half.h>
+#include <asm/barrier.h>
+
+
+/*
+ * Must define these before including other files, inline functions need them
+ */
+#define LOCK_SECTION_NAME ".text..lock."KBUILD_BASENAME
+
+#define LOCK_SECTION_START(extra)               \
+        ".subsection 1\n\t"                     \
+        extra                                   \
+        ".ifndef " LOCK_SECTION_NAME "\n\t"     \
+        LOCK_SECTION_NAME ":\n\t"               \
+        ".endif\n"
+
+#define LOCK_SECTION_END                        \
+        ".previous\n\t"
+
+#define __lockfunc __attribute__((section(".spinlock.text")))
+
+/*
+ * Pull the arch_spinlock_t and arch_rwlock_t definitions:
+ */
+#include <linux/spinlock_types.h>
+
+/*
+ * Pull the arch_spin*() functions/declarations (UP-nondebug doesn't need them):
+ */
+#ifdef CONFIG_SMP
+# include <asm/spinlock.h>
+#else
+# include <linux/spinlock_up.h>
+#endif
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+  extern void __raw_spin_lock_init(raw_spinlock_t *lock, const char *name,
+				   struct lock_class_key *key);
+# define raw_spin_lock_init(lock)				\
+do {								\
+	static struct lock_class_key __key;			\
+								\
+	__raw_spin_lock_init((lock), #lock, &__key);		\
+} while (0)
+
+#else
+# define raw_spin_lock_init(lock)				\
+	do { *(lock) = __RAW_SPIN_LOCK_UNLOCKED(lock); } while (0)
+#endif
+
+#define raw_spin_is_locked(lock)	arch_spin_is_locked(&(lock)->raw_lock)
+
+#ifdef CONFIG_GENERIC_LOCKBREAK
+#define raw_spin_is_contended(lock) ((lock)->break_lock)
+#else
+
+#ifdef arch_spin_is_contended
+#define raw_spin_is_contended(lock)	arch_spin_is_contended(&(lock)->raw_lock)
+#else
+#define raw_spin_is_contended(lock)	(((void)(lock), 0))
+#endif /*arch_spin_is_contended*/
+#endif
+
+/*
+ * Despite its name it doesn't necessarily has to be a full barrier.
+ * It should only guarantee that a STORE before the critical section
+ * can not be reordered with a LOAD inside this section.
+ * spin_lock() is the one-way barrier, this LOAD can not escape out
+ * of the region. So the default implementation simply ensures that
+ * a STORE can not move into the critical section, smp_wmb() should
+ * serialize it with another STORE done by spin_lock().
+ */
+#ifndef smp_mb__before_spinlock
+#define smp_mb__before_spinlock()	smp_wmb()
+#endif
+
+/*
+ * Place this after a lock-acquisition primitive to guarantee that
+ * an UNLOCK+LOCK pair act as a full barrier.  This guarantee applies
+ * if the UNLOCK and LOCK are executed by the same CPU or if the
+ * UNLOCK and LOCK operate on the same lock variable.
+ */
+#ifndef smp_mb__after_unlock_lock
+#define smp_mb__after_unlock_lock()	do { } while (0)
+#endif
+
+/**
+ * raw_spin_unlock_wait - wait until the spinlock gets unlocked
+ * @lock: the spinlock in question.
+ */
+#define raw_spin_unlock_wait(lock)	arch_spin_unlock_wait(&(lock)->raw_lock)
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+ extern void do_raw_spin_lock(raw_spinlock_t *lock) __acquires(lock);
+#define do_raw_spin_lock_flags(lock, flags) do_raw_spin_lock(lock)
+ extern int do_raw_spin_trylock(raw_spinlock_t *lock);
+ extern void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock);
+#else
+static inline void do_raw_spin_lock(raw_spinlock_t *lock) __acquires(lock)
+{
+	__acquire(lock);
+	arch_spin_lock(&lock->raw_lock);
+}
+
+static inline void
+do_raw_spin_lock_flags(raw_spinlock_t *lock, unsigned long *flags) __acquires(lock)
+{
+	__acquire(lock);
+	arch_spin_lock_flags(&lock->raw_lock, *flags);
+}
+
+static inline int do_raw_spin_trylock(raw_spinlock_t *lock)
+{
+	return arch_spin_trylock(&(lock)->raw_lock);
+}
+
+static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
+{
+	arch_spin_unlock(&lock->raw_lock);
+	__release(lock);
+}
+#endif
+
+/*
+ * Define the various spin_lock methods.  Note we define these
+ * regardless of whether CONFIG_SMP or CONFIG_PREEMPT are set. The
+ * various methods are defined as nops in the case they are not
+ * required.
+ */
+#define raw_spin_trylock(lock)	__cond_lock(lock, _raw_spin_trylock(lock))
+
+#define raw_spin_lock(lock)	_raw_spin_lock(lock)
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define raw_spin_lock_nested(lock, subclass) \
+	_raw_spin_lock_nested(lock, subclass)
+# define raw_spin_lock_bh_nested(lock, subclass) \
+	_raw_spin_lock_bh_nested(lock, subclass)
+
+# define raw_spin_lock_nest_lock(lock, nest_lock)			\
+	 do {								\
+		 typecheck(struct lockdep_map *, &(nest_lock)->dep_map);\
+		 _raw_spin_lock_nest_lock(lock, &(nest_lock)->dep_map);	\
+	 } while (0)
+#else
+/*
+ * Always evaluate the 'subclass' argument to avoid that the compiler
+ * warns about set-but-not-used variables when building with
+ * CONFIG_DEBUG_LOCK_ALLOC=n and with W=1.
+ */
+# define raw_spin_lock_nested(lock, subclass)		\
+	_raw_spin_lock(((void)(subclass), (lock)))
+# define raw_spin_lock_nest_lock(lock, nest_lock)	_raw_spin_lock(lock)
+# define raw_spin_lock_bh_nested(lock, subclass)	_raw_spin_lock_bh(lock)
+#endif
+
+#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
+
+#define raw_spin_lock_irqsave(lock, flags)			\
+	do {						\
+		typecheck(unsigned long, flags);	\
+		flags = _raw_spin_lock_irqsave(lock);	\
+	} while (0)
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+#define raw_spin_lock_irqsave_nested(lock, flags, subclass)		\
+	do {								\
+		typecheck(unsigned long, flags);			\
+		flags = _raw_spin_lock_irqsave_nested(lock, subclass);	\
+	} while (0)
+#else
+#define raw_spin_lock_irqsave_nested(lock, flags, subclass)		\
+	do {								\
+		typecheck(unsigned long, flags);			\
+		flags = _raw_spin_lock_irqsave(lock);			\
+	} while (0)
+#endif
+
+#else
+
+#define raw_spin_lock_irqsave(lock, flags)		\
+	do {						\
+		typecheck(unsigned long, flags);	\
+		_raw_spin_lock_irqsave(lock, flags);	\
+	} while (0)
+
+#define raw_spin_lock_irqsave_nested(lock, flags, subclass)	\
+	raw_spin_lock_irqsave(lock, flags)
+
+#endif
+
+#define raw_spin_lock_irq(lock)		_raw_spin_lock_irq(lock)
+#define raw_spin_lock_bh(lock)		_raw_spin_lock_bh(lock)
+#define raw_spin_unlock(lock)		_raw_spin_unlock(lock)
+#define raw_spin_unlock_irq(lock)	_raw_spin_unlock_irq(lock)
+
+#define raw_spin_unlock_irqrestore(lock, flags)		\
+	do {							\
+		typecheck(unsigned long, flags);		\
+		_raw_spin_unlock_irqrestore(lock, flags);	\
+	} while (0)
+#define raw_spin_unlock_bh(lock)	_raw_spin_unlock_bh(lock)
+
+#define raw_spin_trylock_bh(lock) \
+	__cond_lock(lock, _raw_spin_trylock_bh(lock))
+
+#define raw_spin_trylock_irq(lock) \
+({ \
+	local_irq_disable(); \
+	raw_spin_trylock(lock) ? \
+	1 : ({ local_irq_enable(); 0;  }); \
+})
+
+#define raw_spin_trylock_irqsave(lock, flags) \
+({ \
+	local_irq_save(flags); \
+	raw_spin_trylock(lock) ? \
+	1 : ({ local_irq_restore(flags); 0; }); \
+})
+
+/**
+ * raw_spin_can_lock - would raw_spin_trylock() succeed?
+ * @lock: the spinlock in question.
+ */
+#define raw_spin_can_lock(lock)	(!raw_spin_is_locked(lock))
+
+/* Include rwlock functions */
+#include <linux/rwlock.h>
+
+/*
+ * Pull the _spin_*()/_read_*()/_write_*() functions/declarations:
+ */
+#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
+# include <linux/spinlock_api_smp.h>
+#else
+# include <linux/spinlock_api_up.h>
+#endif
+
+/*
+ * Map the spin_lock functions to the raw variants for PREEMPT_RT=n
+ */
+
+static inline raw_spinlock_t *spinlock_check(spinlock_t *lock)
+{
+	return &lock->rlock;
+}
+
+#define spin_lock_init(_lock)				\
+do {							\
+	spinlock_check(_lock);				\
+	raw_spin_lock_init(&(_lock)->rlock);		\
+} while (0)
+
+static inline void spin_lock(spinlock_t *lock)
+{
+	raw_spin_lock(&lock->rlock);
+}
+
+static inline void spin_lock_bh(spinlock_t *lock)
+{
+	raw_spin_lock_bh(&lock->rlock);
+}
+
+static inline int spin_trylock(spinlock_t *lock)
+{
+	return raw_spin_trylock(&lock->rlock);
+}
+
+#define spin_lock_nested(lock, subclass)			\
+do {								\
+	raw_spin_lock_nested(spinlock_check(lock), subclass);	\
+} while (0)
+
+#define spin_lock_bh_nested(lock, subclass)			\
+do {								\
+	raw_spin_lock_bh_nested(spinlock_check(lock), subclass);\
+} while (0)
+
+#define spin_lock_nest_lock(lock, nest_lock)				\
+do {									\
+	raw_spin_lock_nest_lock(spinlock_check(lock), nest_lock);	\
+} while (0)
+
+static inline void spin_lock_irq(spinlock_t *lock)
+{
+	raw_spin_lock_irq(&lock->rlock);
+}
+
+#define spin_lock_irqsave(lock, flags)				\
+do {								\
+	raw_spin_lock_irqsave(spinlock_check(lock), flags);	\
+} while (0)
+
+#define spin_lock_irqsave_nested(lock, flags, subclass)			\
+do {									\
+	raw_spin_lock_irqsave_nested(spinlock_check(lock), flags, subclass); \
+} while (0)
+
+static inline void spin_unlock(spinlock_t *lock)
+{
+	raw_spin_unlock(&lock->rlock);
+}
+
+static inline void spin_unlock_bh(spinlock_t *lock)
+{
+	raw_spin_unlock_bh(&lock->rlock);
+}
+
+static inline void spin_unlock_irq(spinlock_t *lock)
+{
+	raw_spin_unlock_irq(&lock->rlock);
+}
+
+static inline void spin_unlock_irqrestore(spinlock_t *lock, unsigned long flags)
+{
+	raw_spin_unlock_irqrestore(&lock->rlock, flags);
+}
+
+static inline int spin_trylock_bh(spinlock_t *lock)
+{
+	return raw_spin_trylock_bh(&lock->rlock);
+}
+
+static inline int spin_trylock_irq(spinlock_t *lock)
+{
+	return raw_spin_trylock_irq(&lock->rlock);
+}
+
+#define spin_trylock_irqsave(lock, flags)			\
+({								\
+	raw_spin_trylock_irqsave(spinlock_check(lock), flags); \
+})
+
+static inline void spin_unlock_wait(spinlock_t *lock)
+{
+	raw_spin_unlock_wait(&lock->rlock);
+}
+
+static inline int spin_is_locked(spinlock_t *lock)
+{
+	return raw_spin_is_locked(&lock->rlock);
+}
+
+static inline int spin_is_contended(spinlock_t *lock)
+{
+	return raw_spin_is_contended(&lock->rlock);
+}
+
+static inline int spin_can_lock(spinlock_t *lock)
+{
+	return raw_spin_can_lock(&lock->rlock);
+}
+
+#define assert_spin_locked(lock)	assert_raw_spin_locked(&(lock)->rlock)
+
+/*
+ * Pull the atomic_t declaration:
+ * (asm-mips/atomic.h needs above definitions)
+ */
+#include <linux/atomic.h>
+/**
+ * atomic_dec_and_lock - lock on reaching reference count zero
+ * @atomic: the atomic counter
+ * @lock: the spinlock in question
+ *
+ * Decrements @atomic by 1.  If the result is 0, returns true and locks
+ * @lock.  Returns false for all other cases.
+ */
+extern int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock);
+#define atomic_dec_and_lock(atomic, lock) \
+		__cond_lock(lock, _atomic_dec_and_lock(atomic, lock))
+
+#endif /* __LINUX_SPINLOCK_H */