locking: Implement new raw_spinlock
Now that the raw_spin name space is freed up, we can implement
raw_spinlock and the related functions which are used to annotate the
locks which are not converted to sleeping spinlocks in preempt-rt.
A side effect is that only such locks can be used with the low level
lock fsunctions which circumvent lockdep.
For !rt spin_* functions are mapped to the raw_spin* implementations.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h
index 53bc221..ef5a55d 100644
--- a/include/linux/spinlock.h
+++ b/include/linux/spinlock.h
@@ -80,7 +80,7 @@
#include <linux/spinlock_types.h>
/*
- * Pull the __raw*() functions/declarations (UP-nondebug doesnt need them):
+ * Pull the arch_spin*() functions/declarations (UP-nondebug doesnt need them):
*/
#ifdef CONFIG_SMP
# include <asm/spinlock.h>
@@ -89,30 +89,30 @@
#endif
#ifdef CONFIG_DEBUG_SPINLOCK
- extern void __spin_lock_init(spinlock_t *lock, const char *name,
- struct lock_class_key *key);
-# define spin_lock_init(lock) \
+ 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; \
\
- __spin_lock_init((lock), #lock, &__key); \
+ __raw_spin_lock_init((lock), #lock, &__key); \
} while (0)
#else
-# define spin_lock_init(lock) \
- do { *(lock) = __SPIN_LOCK_UNLOCKED(lock); } while (0)
+# define raw_spin_lock_init(lock) \
+ do { *(lock) = __RAW_SPIN_LOCK_UNLOCKED(lock); } while (0)
#endif
-#define spin_is_locked(lock) arch_spin_is_locked(&(lock)->raw_lock)
+#define raw_spin_is_locked(lock) arch_spin_is_locked(&(lock)->raw_lock)
#ifdef CONFIG_GENERIC_LOCKBREAK
-#define spin_is_contended(lock) ((lock)->break_lock)
+#define raw_spin_is_contended(lock) ((lock)->break_lock)
#else
#ifdef arch_spin_is_contended
-#define spin_is_contended(lock) arch_spin_is_contended(&(lock)->raw_lock)
+#define raw_spin_is_contended(lock) arch_spin_is_contended(&(lock)->raw_lock)
#else
-#define spin_is_contended(lock) (((void)(lock), 0))
+#define raw_spin_is_contended(lock) (((void)(lock), 0))
#endif /*arch_spin_is_contended*/
#endif
@@ -122,22 +122,37 @@
#endif
/**
- * spin_unlock_wait - wait until the spinlock gets unlocked
+ * raw_spin_unlock_wait - wait until the spinlock gets unlocked
* @lock: the spinlock in question.
*/
-#define spin_unlock_wait(lock) arch_spin_unlock_wait(&(lock)->raw_lock)
+#define raw_spin_unlock_wait(lock) arch_spin_unlock_wait(&(lock)->raw_lock)
#ifdef CONFIG_DEBUG_SPINLOCK
- extern void _raw_spin_lock(spinlock_t *lock);
+ extern void _raw_spin_lock(raw_spinlock_t *lock);
#define _raw_spin_lock_flags(lock, flags) _raw_spin_lock(lock)
- extern int _raw_spin_trylock(spinlock_t *lock);
- extern void _raw_spin_unlock(spinlock_t *lock);
+ extern int _raw_spin_trylock(raw_spinlock_t *lock);
+ extern void _raw_spin_unlock(raw_spinlock_t *lock);
#else
-# define _raw_spin_lock(lock) arch_spin_lock(&(lock)->raw_lock)
-# define _raw_spin_lock_flags(lock, flags) \
- arch_spin_lock_flags(&(lock)->raw_lock, *(flags))
-# define _raw_spin_trylock(lock) arch_spin_trylock(&(lock)->raw_lock)
-# define _raw_spin_unlock(lock) arch_spin_unlock(&(lock)->raw_lock)
+static inline void _raw_spin_lock(raw_spinlock_t *lock)
+{
+ arch_spin_lock(&lock->raw_lock);
+}
+
+static inline void
+_raw_spin_lock_flags(raw_spinlock_t *lock, unsigned long *flags)
+{
+ arch_spin_lock_flags(&lock->raw_lock, *flags);
+}
+
+static inline int _raw_spin_trylock(raw_spinlock_t *lock)
+{
+ return arch_spin_trylock(&(lock)->raw_lock);
+}
+
+static inline void _raw_spin_unlock(raw_spinlock_t *lock)
+{
+ arch_spin_unlock(&lock->raw_lock);
+}
#endif
/*
@@ -146,38 +161,38 @@
* various methods are defined as nops in the case they are not
* required.
*/
-#define spin_trylock(lock) __cond_lock(lock, _spin_trylock(lock))
+#define raw_spin_trylock(lock) __cond_lock(lock, _spin_trylock(lock))
-#define spin_lock(lock) _spin_lock(lock)
+#define raw_spin_lock(lock) _spin_lock(lock)
#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define spin_lock_nested(lock, subclass) _spin_lock_nested(lock, subclass)
-# define spin_lock_nest_lock(lock, nest_lock) \
+# define raw_spin_lock_nested(lock, subclass) _spin_lock_nested(lock, subclass)
+# define raw_spin_lock_nest_lock(lock, nest_lock) \
do { \
typecheck(struct lockdep_map *, &(nest_lock)->dep_map);\
_spin_lock_nest_lock(lock, &(nest_lock)->dep_map); \
} while (0)
#else
-# define spin_lock_nested(lock, subclass) _spin_lock(lock)
-# define spin_lock_nest_lock(lock, nest_lock) _spin_lock(lock)
+# define raw_spin_lock_nested(lock, subclass) _spin_lock(lock)
+# define raw_spin_lock_nest_lock(lock, nest_lock) _spin_lock(lock)
#endif
#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
-#define spin_lock_irqsave(lock, flags) \
+#define raw_spin_lock_irqsave(lock, flags) \
do { \
typecheck(unsigned long, flags); \
flags = _spin_lock_irqsave(lock); \
} while (0)
#ifdef CONFIG_DEBUG_LOCK_ALLOC
-#define spin_lock_irqsave_nested(lock, flags, subclass) \
+#define raw_spin_lock_irqsave_nested(lock, flags, subclass) \
do { \
typecheck(unsigned long, flags); \
flags = _spin_lock_irqsave_nested(lock, subclass); \
} while (0)
#else
-#define spin_lock_irqsave_nested(lock, flags, subclass) \
+#define raw_spin_lock_irqsave_nested(lock, flags, subclass) \
do { \
typecheck(unsigned long, flags); \
flags = _spin_lock_irqsave(lock); \
@@ -186,45 +201,178 @@
#else
-#define spin_lock_irqsave(lock, flags) \
+#define raw_spin_lock_irqsave(lock, flags) \
do { \
typecheck(unsigned long, flags); \
_spin_lock_irqsave(lock, flags); \
} while (0)
-#define spin_lock_irqsave_nested(lock, flags, subclass) \
- spin_lock_irqsave(lock, flags)
+#define raw_spin_lock_irqsave_nested(lock, flags, subclass) \
+ raw_spin_lock_irqsave(lock, flags)
#endif
-#define spin_lock_irq(lock) _spin_lock_irq(lock)
-#define spin_lock_bh(lock) _spin_lock_bh(lock)
-#define spin_unlock(lock) _spin_unlock(lock)
-#define spin_unlock_irq(lock) _spin_unlock_irq(lock)
+#define raw_spin_lock_irq(lock) _spin_lock_irq(lock)
+#define raw_spin_lock_bh(lock) _spin_lock_bh(lock)
+#define raw_spin_unlock(lock) _spin_unlock(lock)
+#define raw_spin_unlock_irq(lock) _spin_unlock_irq(lock)
-#define spin_unlock_irqrestore(lock, flags) \
- do { \
- typecheck(unsigned long, flags); \
+#define raw_spin_unlock_irqrestore(lock, flags) \
+ do { \
+ typecheck(unsigned long, flags); \
_spin_unlock_irqrestore(lock, flags); \
} while (0)
-#define spin_unlock_bh(lock) _spin_unlock_bh(lock)
+#define raw_spin_unlock_bh(lock) _spin_unlock_bh(lock)
-#define spin_trylock_bh(lock) __cond_lock(lock, _spin_trylock_bh(lock))
+#define raw_spin_trylock_bh(lock) __cond_lock(lock, _spin_trylock_bh(lock))
-#define spin_trylock_irq(lock) \
+#define raw_spin_trylock_irq(lock) \
({ \
local_irq_disable(); \
- spin_trylock(lock) ? \
+ raw_spin_trylock(lock) ? \
1 : ({ local_irq_enable(); 0; }); \
})
-#define spin_trylock_irqsave(lock, flags) \
+#define raw_spin_trylock_irqsave(lock, flags) \
({ \
local_irq_save(flags); \
- spin_trylock(lock) ? \
+ 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_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);
+}
+
+static inline void assert_spin_locked(spinlock_t *lock)
+{
+ assert_raw_spin_locked(&lock->rlock);
+}
+
/*
* Pull the atomic_t declaration:
* (asm-mips/atomic.h needs above definitions)
@@ -242,22 +390,4 @@
#define atomic_dec_and_lock(atomic, lock) \
__cond_lock(lock, _atomic_dec_and_lock(atomic, lock))
-/**
- * spin_can_lock - would spin_trylock() succeed?
- * @lock: the spinlock in question.
- */
-#define spin_can_lock(lock) (!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
-
#endif /* __LINUX_SPINLOCK_H */