Re: [PATCH net-next 0/6] xfrm: convert xfrm_state_find to rcu

[Steffen Klassert <steffen.klassert@secunet.com>]

On Tue, Aug 09, 2016 at 12:16:03PM +0200, Florian Westphal wrote:
> This series converts state_by{dst,src,spi} to allow lookups without
> holding xfrm_state_lock.
> 
> Only xfrm_state_find() is converted here for the (more common) case where
> we do not query key manager.
> 
> Once more flows are created/destroyed (or the flow cache is overloaded and
> often cleans out other entries) this function (and the state lock)
> start to show up in perf.
> 
> Florian Westphal (6):
>       xfrm: state: use hlist_for_each_entry_rcu helper
>       xfrm: state: use atomic_inc_not_zero to increment refcount
>       xfrm: state: delay freeing until rcu grace period has elapsed
>       xfrm: state: add sequence count to detect hash resizes
>       xfrm: state: use rcu_deref and assign_pointer helpers
>       xfrm: state: don't use lock anymore unless acquire operation is needed
> 
>  include/net/netns/xfrm.h |    6 +-
>  net/xfrm/xfrm_state.c    |  103 +++++++++++++++++++++++++++++++----------------
>  2 files changed, 72 insertions(+), 37 deletions(-)

All applied to the ipsec-next tree, thanks Florian!