# error "please don't include this file directly"
#endif
+ #include <linux/types.h>
+
+ #if (CONFIG_NR_CPUS < 256)
+ typedef u8 __ticket_t;
+ typedef u16 __ticketpair_t;
+ #else
+ typedef u16 __ticket_t;
+ typedef u32 __ticketpair_t;
+ #endif
+
+ #define TICKET_SHIFT (sizeof(__ticket_t) * 8)
+ #define TICKET_MASK ((__ticket_t)((1 << TICKET_SHIFT) - 1))
+
typedef struct arch_spinlock {
- unsigned int slock;
+ union {
+ __ticketpair_t head_tail;
+ struct __raw_tickets {
+ __ticket_t head, tail;
+ } tickets;
+ };
} arch_spinlock_t;
- #define __ARCH_SPIN_LOCK_UNLOCKED { 0 }
+ #define __ARCH_SPIN_LOCK_UNLOCKED { { 0 } }
-typedef struct {
- unsigned int lock;
-} arch_rwlock_t;
-
-#define __ARCH_RW_LOCK_UNLOCKED { RW_LOCK_BIAS }
+#include <asm/rwlock.h>
#endif /* _ASM_X86_SPINLOCK_TYPES_H */
*
* Atomically adds @i to @v and returns @i + @v
*/
-static inline int atomic_add_short_return(short i, struct atomic_short *v)
+static inline int atom_asr(short i, struct atomic_short *v)
{
- short __i = i;
- asm volatile(LOCK_PREFIX "xaddw %0, %1"
- : "+r" (i), "+m" (v->counter)
- : : "memory");
- return i + __i;
+ return i + xadd(&v->counter, i);
}
+/*
+ * conditionally add 1 to *v, unless *v is >= u
+ * return 0 if we cannot add 1 to *v because it is >= u
+ * return 1 if we can add 1 to *v because it is < u
+ * the add is atomic
+ *
+ * This is close to atomic_add_unless(), but this allows the 'u' value
+ * to be lowered below the current 'v'. atomic_add_unless can only stop
+ * on equal.
+ */
+static inline int atomic_inc_unless_ge(spinlock_t *lock, atomic_t *v, int u)
+{
+ spin_lock(lock);
+ if (atomic_read(v) >= u) {
+ spin_unlock(lock);
+ return 0;
+ }
+ atomic_inc(v);
+ spin_unlock(lock);
+ return 1;
+}
+
#endif /* _ASM_X86_UV_UV_BAU_H */