Re: [PATCH] ioeventfd: Introduce KVM_IOEVENTFD_FLAG_PIPE

[Avi Kivity <avi@redhat.com>]

On 07/04/2011 05:52 PM, Sasha Levin wrote:
> >
> >  I can't really see that as useful.  eventfds destroy information;
> >  without datamatch, you have no idea what value was written.  Even with
> >  datamatch, you have no idea how many times it was written.  With a
> >  range, you also have no idea which address was written.  It's pretty
> >  meaningless.
> >
>
> It is pretty useless, but I didn't want the ioctl to behave differently
> when passing a socket or an eventfd.
>
> If we do go for a new ioctl as you suggested then yes, problem solved.
>

Yes.  I guess it depends on the numbers of if () s introduced into the 
code.  If it starts to feel dirty, split it into a separate ioctl (they 
can both call common helpers).

It's fine to allow size > 8 for eventfds.  Yes it's meaningless, but 
it's not harmful and I can't see it breaking anything.  Note that we may 
need to change the way we do matches - currently 'size' means the access 
size, with an exact match on the address, but the new meaning is 'any 
address from start to start+size-1'.

-- 
error compiling committee.c: too many arguments to function