Re: [PATCH] x86/paravirt: Cleanup native_patch()

[Juergen Gross]

On 10/09/18 09:01, Borislav Petkov wrote:
> On Mon, Sep 10, 2018 at 08:54:12AM +0200, Juergen Gross wrote:
>>> +	case PARAVIRT_PATCH(lock.queued_spin_unlock):
>>> +		if (pv_is_native_spin_unlock())
>>> +			return paravirt_patch_insns(ibuf, len,
>>> +						    start_lock_queued_spin_unlock,
>>> +						    end_lock_queued_spin_unlock);
>>> +		else
>>> +			return paravirt_patch_default(type, ibuf, addr, len);
>>
>> Why not replace the else clause by a "break;" and ...
> 
> Because I think that exiting right then and there is much easier to
> follow than adding all those breaks and wading through ifdeffery
> to realize that this is the default path and we'll end up calling
> paravirt_patch_default() in the end.
> 

Really? All of the remaining coding would fit easily on one screen. No
hidden breaks anywhere and no deep nesting involved. And the ifdefs
hardly makes it more difficult to understand, as they are not even
nested.


Juergen