v1: https://lists.gnu.org/archive/html/qemu-devel/2016-05/msg03661.html
Patch 1 hasn't changed from v1 (where it was patch 2 though).
Patches 2 and 3 fix a not-so-small-after-all RCU performance regression
we introduced when transitioning to __atomic primitives. I got
an arm64 machine to test today and a workload that issues a lot of
atomic_read_rcu's, such as a 100%-lookup qht-bench test,
can gain ~12% in performance. [ in v1's 0/2 message I mentioned rcutorture;
It turns out it's not as dependent on atomic_read_rcu as I thought,
so it's not a good benchmark to measure this effect. ]
Thanks,
Emilio
