X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Fasm-x86_64%2Fspinlock.h;h=5aeb57a3baad30b7111aa28cc6149cf891394bd5;hb=6a77f38946aaee1cd85eeec6cf4229b204c15071;hp=185e087e88ab821acd287082ecd506a4335691e9;hpb=87fc8d1bb10cd459024a742c6a10961fefcef18f;p=linux-2.6.git

diff --git a/include/asm-x86_64/spinlock.h b/include/asm-x86_64/spinlock.h
index 185e087e8..5aeb57a3b 100644
--- 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;