From mboxrd@z Thu Jan  1 00:00:00 1970
From: Florian Westphal <fw@strlen.de>
Subject: [PATCH ipsec-next 0/6] xfrm: remove xfrm_state_get_afinfo conditional rcu locking
Date: Mon,  9 Jan 2017 14:20:44 +0100
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xfrm_state_get_afinfo still uses a conditional locking scheme
dating back to when this still used an rwlock:

If return value is NULL, no lock (rcu readlock) was taken,
otherwise, rcu_read_unlock has to be called.

This series moves rcu read lock/unlock responsibility to the callers.

xfrm_state_put_afinfo is removed (it is equivalent
to rcu_read_unlock so thats what will be used instead).

xfrm_state_get_afinfo is renamed to xfrm_state_afinfo_get_rcu()
and is only a rcu dereference wrapper.

In one case, rcu read/unlock can be avoided as we're always
called with rcu read lock held.