Re: [RFC][PATCH] module: Optimize __module_address() using a latched RB-tree

From: Peter Zijlstra
Date: Sat Feb 28 2015 - 11:57:07 EST


On Sat, Feb 28, 2015 at 05:41:12PM +0100, Peter Zijlstra wrote:
> > > > + rb_link_node(&mn->node, parent, link);
> > >
> > > This makes the new module visible to readers, if I understand correctly.
> >
> > You do.
>
> I think I have reconsidered; this does not in fact make it visible.

Ah; never mind, it is. An iterator could have started in data[0], gone
on holiday while the modification took place, and resumed once it is
done and magically see the element appear.

Therefore we do indeed need the atomic publishing and I think this also
settles my question about Alpha.
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