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Re: pool_cache_invalidate(9) (wrong?) semantic -- enable xcall invalidation



Jean-Yves Migeon <jeanyves.migeon%free.fr@localhost> wrote:
> On 25.09.2011 01:50, Jean-Yves Migeon wrote:
> > I would like to turn back on the xcall(9) block found in
> > pool_cache_invalidate(), now that rmind@ has implemented high priority
> > cross calls [1].
> 
> FWIW, I am still struggling with this, without really having an idea on 
> how to fix this once and for all.
> 
> I only investigated two solutions, each one has its own share of 
> problems. Please let me if you see other possibilities:
> 
> 1 # adding an "invalidate flag" to the pool cache, for each CPU. <...>
> 

It is not really desirable to have extra (even if very small) overhead in
pool_cache_get() for a case which is particularly rare.  The real problem
is the synchronisation in interrupt context.  How about looking for a
solution which avoids interrupt context?

-- 
Mindaugas


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