On Wed, Dec 24, 2008 at 08:46:56PM +0300, Vladislav Bolkhovitin (vst@vlnb.net) wrote:

I think in most cases there would be possibility to embed 
sk_transaction_token to some higher level structure. E.g. Xen apparently 
should have something to track packets passed through host/guest 
boundary. From other side, kmem cache is too well polished to have much 
overhead. I doubt, you would even notice it in this application. In most 
cases allocation of such small object in it using SLUB is just about the 
same as a list_del() under disabled IRQs.

I definitely would not rely on that, especially at cache reclaim time.
But it of course depends on the workload and maybe appropriate for the
cases in question. The best solution I think is to combine tag and
separate destructur, so that those who do not want to allocate a token
could still get notification via destructor callback.

-- 
	Evgeniy Polyakov