[Cbe-oss-dev] [PATCH] spusched: extend list_mutex coverage

[Christoph Hellwig]

On Wed, Jul 23, 2008 at 09:16:48PM +1000, Jeremy Kerr wrote:
> Christoph,
> 
> > In both cases we take list_mutex check for spu->ctx, the unlock it
> > <-- race happens here --> then take the state_mutex.
> 
> Sure, but:
> 
>  * in find_victim() we re-check victim->ctx after taking the  
>    victim's state_mutex; and

Stable doesn't only mean it's the same, it also implies that it's
still there.  Without the list_mutex there is no guarantee victim
hasn't been freed in the meantime.  The same also applies to the
scheduler thread.