Re: [PATCH 3/4] KVM-S390: Less function calls in kvm_s390_import_bp_data() after error detection

SF Markus Elfring
2016-08-22T21:17:26Z

>>>> @@ -273,10 +273,12 @@ int kvm_s390_import_bp_data(struct kvm_vcpu *vcpu,
>>>> vcpu->arch.guestdbg.nr_hw_wp = nr_wp;
>>>> vcpu->arch.guestdbg.hw_wp_info = wp_info;
>>>> return 0;
>>>> -error:
>>>> - kfree(bp_data);
>>>> - kfree(wp_info);
>>>> +free_bp_info:
>>>> kfree(bp_info);
>>>> +free_wp_info:
>>>> + kfree(wp_info);
>>>> +free_bp_data:
>>>> + kfree(bp_data);
>>>> return ret;
>>>> }
>>>>
>>>
>>> This replaces a perfectly fine fallthrough
>>
>> The usage of a single goto label like "error" seems to be convenient.
>> But how do these habits fit to the current Linux coding style convention?
>>
>>
>>> with some horrible labels.
>>
>> Do they explain better which processing steps should be performed
>> for an efficient exception handling in this function implementation?
>
> *sigh*
>
> It's _exception handling_. It does not need to be "efficient",

I imagine that run time situations could evolve where software efficiency
will also matter for this purpose.

> it needs to be easily parsable by humans.

I guess that we have got different preferences for this detail.

> If in doubt, the compiler will be _much_ better at optimizing
> that kind of stuff anyway.

Which compiler (or optimizer) implementation is capable to restructure
the jump targets for you automatically in the way I propose here?

Regards,
Markus