Re: [PATCH] memory: transaction API

[Avi Kivity <avi@redhat.com>]

On 07/21/2011 03:26 PM, Ferry Huberts wrote:
> >>  >   +void memory_region_transaction_begin(void)
> >>  >   +{
> >>  >   +    ++memory_region_transaction_depth;
> >>  >   +}
> >>  >   +
> >>
> >>  wouldn't you rather keep it safe by doing either here
> >>
> >>  if (!memory_region_transaction_depth)
> >>     memory_region_transaction_depth++;
> >>
> >
> >  Why? I want to allow nesting transactions (not that I anticipate such a
> >  case).
> >
>
> doesn't memory_region_update_topology commit all accumulated changes?

It does.

>   if
> it does then memory_region_transaction_depth is left non-zero in the
> nesting case while no more changes are actually present, resulting in
> superfluous calls to memory_region_update_topology.
>
> maybe I misunderstood memory_region_update_topology?
>

update_mapping()
{
m_r_t_begin();
// call memory API functions to change hierarchy
some_other_function() entered
   m_r_t_begin();
   // call more memory API functions to change hierarchy
   m_r_t_commit();  // nothing happens
some_other_function() exits
// call even more memory API functions to change hierarchy
m_r_t_commit();  // all accumulated changes become visible
}

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