gistfile1.c

static inline void arch_spin_lock(arch_spinlock_t *lock)
{
	unsigned long tmp;
	__asm__ __volatile__(
1: "1:	ldrex	%0, [%1]\n"
2: "	teq	%0, #0\n"
3:	WFE("ne")
4: "	strexeq	%0, %2, [%1]\n"
5: "	teqeq	%0, #0\n"
6: "	bne	1b"
 	: "=&r" (tmp)
	: "r" (&lock->lock), "r" (1)
	: "cc");
7:	smp_mb();
}