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From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH v2 1/2] tcp: add generic netlink support for tcp_metrics
Date: Tue, 04 Sep 2012 15:47:08 -0400 (EDT)
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From: Julian Anastasov <ja@ssi.bg>
Date: Mon, 3 Sep 2012 11:22:15 +0300 (EEST)

> 	BTW, is it appropriate to use kmem_cache for
> metrics and as result call_rcu for freeing?

I think it would work as things are implemented currently in
slab/slub/slob, however I would not rely upon it.

If you do move to a SLAB cache for the tcp metrics objects,
you might consider SLAB_DESTROY_BY_RCU.  It's a very delicate
facility (read the huge comment in linux/slab.h) but I think
it provides the semantics we need for TCP metrics blobs.

Looking forward to v3 :-)