vserver 1.9.3

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

diff --git a/include/asm-alpha/spinlock.h b/include/asm-alpha/spinlock.h
index 1fc53a9..b5f3554 100644 (file)
--- a/include/asm-alpha/spinlock.h
+++ b/include/asm-alpha/spinlock.h
@@ -95,7 +95,7 @@ static inline int _raw_spin_trylock(spinlock_t *lock)
 /***********************************************************/
 
 typedef struct {
-       volatile int write_lock:1, read_counter:31;
+       volatile unsigned int write_lock:1, read_counter:31;
 } /*__attribute__((aligned(32)))*/ rwlock_t;
 
 #define RW_LOCK_UNLOCKED (rwlock_t) { 0, 0 }
@@ -124,7 +124,7 @@ static inline void _raw_write_lock(rwlock_t * lock)
        "       br      1b\n"
        ".previous"
        : "=m" (*lock), "=&r" (regx)
-       : "0" (*lock) : "memory");
+       : "m" (*lock) : "memory");
 }
 
 static inline void _raw_read_lock(rwlock_t * lock)
@@ -148,6 +148,29 @@ static inline void _raw_read_lock(rwlock_t * lock)
 }
 #endif /* CONFIG_DEBUG_RWLOCK */
 
+static inline int _raw_write_trylock(rwlock_t * lock)
+{
+       long regx;
+       int success;
+
+       __asm__ __volatile__(
+       "1:     ldl_l   %1,%0\n"
+       "       lda     %2,0\n"
+       "       bne     %1,2f\n"
+       "       or      $31,1,%1\n"
+       "       stl_c   %1,%0\n"
+       "       beq     %1,6f\n"
+       "       lda     %2,1\n"
+       "2:     mb\n"
+       ".subsection 2\n"
+       "6:     br      1b\n"
+       ".previous"
+       : "=m" (*lock), "=&r" (regx), "=&r" (success)
+       : "m" (*lock) : "memory");
+
+       return success;
+}
+
 static inline void _raw_write_unlock(rwlock_t * lock)
 {
        mb();