Re: [PATCH v2 1/4] virtio_balloon: separate vm events into a function

[David Hildenbrand]

On 22.04.24 10:04, zhenwei pi wrote:
> On 4/22/24 15:47, David Hildenbrand wrote:
> > On 22.04.24 09:42, zhenwei pi wrote:
> > > All the VM events related statistics have dependence on
> > > 'CONFIG_VM_EVENT_COUNTERS', once any stack variable is required by any
> > > VM events in future, we would have codes like:
> > >    #ifdef CONFIG_VM_EVENT_COUNTERS
> > >         unsigned long foo;
> > >    #endif
> > >         ...
> > >    #ifdef CONFIG_VM_EVENT_COUNTERS
> > >         foo = events[XXX] + events[YYY];
> > >         update_stat(vb, idx++, VIRTIO_BALLOON_S_XXX, foo);
> > >    #endif
> > >
> > > Separate vm events into a single function, also remove
> >
> > Why not simply use __maybe_unused for that variable?
>
> 1>
> static unsigned int update_balloon_stats()
> {
>       unsigned __maybe_unused long foo;
>
>       ...
> #ifdef CONFIG_VM_EVENT_COUNTERS
>       foo = events[XXX] + events[YYY];
>       update_stat(vb, idx++, VIRTIO_BALLOON_S_XXX, foo);
> #endif
> }
>
> 2>
> static inline unsigned int update_balloon_vm_stats()
> {
> #ifdef CONFIG_VM_EVENT_COUNTERS
>       unsigned long foo;
>
>       foo = events[XXX] + events[YYY];
>       update_stat(vb, idx++, VIRTIO_BALLOON_S_XXX, foo);
> #endif
> }
>
>   From the point of my view, I don't need to compile code in my brain
> when reading codes for case 2. :)

But for #1? :)

I mean, you didn't compile the code in your brain when you sent out v1 :P

But I agree that moving that to a separate function ins cleaner, staring 
at resulting update_balloon_stats().

Let me comment on some nits as a fresh reply.

--
Cheers,

David / dhildenb