sys_getxpid:    
        .prologue 0 
        ldq     $2, TI_TASK($8)

        /* See linux/kernel/timer.c sys_getppid for discussion
           about this loop.  */
        ldq     $3, TASK_REAL_PARENT($2)
1:      ldl     $1, TASK_TGID($3)
#ifdef CONFIG_SMP
        mov     $3, $4
        mb
        ldq     $3, TASK_REAL_PARENT($2)
        cmpeq   $3, $4, $4
        beq     $4, 1b
#endif
        stq     $1, 80($sp)
        ldl     $0, TASK_TGID($2)
        ret
.end sys_getxpid