Re: Adding pool_cache_invalidate_local() to pool_cache(9) API

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Fri, Oct 09, 2009 at 07:35:14AM -0700, Matt Thomas wrote:
> Do it lazily.  Set a flag in each per-cpu queue and next time an item  
> that
> cpu accesses its per-cpu cache, it can see the cache is invalid and  
> discard it.
> This doesn't solve the window of that cpu already actively using the  
> pool
> while the flag is set but it could that could solved by get testing the 
> test on
> exit, if set discarding the item, and retrying.

This doesn't really fix the Xen issue where we need to destroy the cache
content *now*.

>
> No reason for exposing the mechanics of how to do this to the users of  
> the
> poll APIs.

I see no reason to hide it either, especially when we know that the
CPU is being shut down and the cache won't be of any use after that.

-- 
Manuel Bouyer, LIP6, Universite Paris VI.           
Manuel.Bouyer%lip6.fr@localhost
     NetBSD: 26 ans d'experience feront toujours la difference
--