vserver 1.9.5.x5

[linux-2.6.git] / include / asm-x86_64 / spinlock.h

diff --git a/include/asm-x86_64/spinlock.h b/include/asm-x86_64/spinlock.h
index 185e087..5aeb57a 100644 (file)
--- a/include/asm-x86_64/spinlock.h
+++ b/include/asm-x86_64/spinlock.h
@@ -18,6 +18,9 @@ typedef struct {
 #ifdef CONFIG_DEBUG_SPINLOCK
        unsigned magic;
 #endif
+#ifdef CONFIG_PREEMPT
+       unsigned int break_lock;
+#endif
 } spinlock_t;
 
 #define SPINLOCK_MAGIC 0xdead4ead
@@ -72,7 +75,7 @@ static inline void _raw_spin_unlock(spinlock_t *lock)
 {
 #ifdef CONFIG_DEBUG_SPINLOCK
        BUG_ON(lock->magic != SPINLOCK_MAGIC);
-       BUG_ON(!spin_is_locked(lock));
+       assert_spin_locked(lock);
 #endif
        __asm__ __volatile__(
                spin_unlock_string
@@ -91,7 +94,7 @@ static inline void _raw_spin_unlock(spinlock_t *lock)
        char oldval = 1;
 #ifdef CONFIG_DEBUG_SPINLOCK
        BUG_ON(lock->magic != SPINLOCK_MAGIC);
-       BUG_ON(!spin_is_locked(lock));
+       assert_spin_locked(lock);
 #endif
        __asm__ __volatile__(
                spin_unlock_string
@@ -139,6 +142,9 @@ typedef struct {
 #ifdef CONFIG_DEBUG_SPINLOCK
        unsigned magic;
 #endif
+#ifdef CONFIG_PREEMPT
+       unsigned int break_lock;
+#endif
 } rwlock_t;
 
 #define RWLOCK_MAGIC   0xdeaf1eed
@@ -153,7 +159,8 @@ typedef struct {
 
 #define rwlock_init(x) do { *(x) = RW_LOCK_UNLOCKED; } while(0)
 
-#define rwlock_is_locked(x) ((x)->lock != RW_LOCK_BIAS)
+#define read_can_lock(x)       ((int)(x)->lock > 0)
+#define write_can_lock(x)      ((x)->lock == RW_LOCK_BIAS)
 
 /*
  * On x86, we implement read-write locks as a 32-bit counter
@@ -185,6 +192,16 @@ static inline void _raw_write_lock(rwlock_t *rw)
 #define _raw_read_unlock(rw)           asm volatile("lock ; incl %0" :"=m" ((rw)->lock) : : "memory")
 #define _raw_write_unlock(rw)  asm volatile("lock ; addl $" RW_LOCK_BIAS_STR ",%0":"=m" ((rw)->lock) : : "memory")
 
+static inline int _raw_read_trylock(rwlock_t *lock)
+{
+       atomic_t *count = (atomic_t *)lock;
+       atomic_dec(count);
+       if (atomic_read(count) >= 0)
+               return 1;
+       atomic_inc(count);
+       return 0;
+}
+
 static inline int _raw_write_trylock(rwlock_t *lock)
 {
        atomic_t *count = (atomic_t *)lock;