ftrace_get_call_inst
ret = ftrace_get_call_inst(rec, (unsigned long)ftrace_caller, &inst);
ret = ftrace_get_call_inst(rec, (unsigned long)ftrace_caller, &old);
ret |= ftrace_get_call_inst(rec, addr, &new);
ret = ftrace_get_call_inst(rec, (unsigned long)ftrace_caller, &nop_inst);
ret = ftrace_get_call_inst(rec, new_addr, &new_call_inst);
ret |= ftrace_get_call_inst(rec, addr, &call_inst);
ret = ftrace_get_call_inst(rec, addr, &call_inst);
ret = ftrace_get_call_inst(rec, new_addr, &call_inst);