#define read_barrier() __asm__ __volatile__ ("" : : : "memory")
#define write_barrier() __asm__ __volatile__ ("" : : : "memory")
+typedef struct {
+ volatile unsigned char lock;
+} spinlock_t;
+
+static inline void spin_lock(spinlock_t *lock)
+{
+ __asm__ __volatile__(
+ "\n1:\n\t"
+ "ldstub [%0], %%g2\n\t"
+ "orcc %%g2, 0x0, %%g0\n\t"
+ "bne,a 2f\n\t"
+ " ldub [%0], %%g2\n\t"
+ ".subsection 2\n"
+ "2:\n\t"
+ "orcc %%g2, 0x0, %%g0\n\t"
+ "bne,a 2b\n\t"
+ " ldub [%0], %%g2\n\t"
+ "b,a 1b\n\t"
+ ".previous\n"
+ : /* no outputs */
+ : "r" (lock)
+ : "g2", "memory", "cc");
+}
+
+static inline void spin_unlock(spinlock_t *lock)
+{
+ __asm__ __volatile__("stb %%g0, [%0]" : : "r" (lock) : "memory");
+}
+
#endif