Re: [PATCH 1/2] tracing/events: clean up for ftrace_set_clr_event()

[Li Zefan <lizf@cn.fujitsu.com>]

>> @@ -500,30 +505,16 @@ system_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
>>  	if (ret < 0)
>>  		return ret;
>>  
>> -	switch (val) {
>> -	case 0:
>> -	case 1:
>> -		break;
>> -
>> -	default:
>> +	if (val != 0 && val != 1)
> 
> What about "if (val & ~1UL)"?
> 

I tried it just now:

   text    data     bss     dec     hex filename
   7480     104       8    7592    1da8 kernel/trace/trace_events.o.orig
   text    data     bss     dec     hex filename
   7482     104       8    7594    1daa kernel/trace/trace_events.o

It increased text size by 2 bytes, gcc did a better work. ;)

And it's not so intuitive what's the limit of val.