Merge branch 'bulk-cpumap-redirect'

Jesper Dangaard Brouer says:

====================
This patchset utilize a number of different kernel bulk APIs for optimizing
the performance for the XDP cpumap redirect feature.

Benchmark details are available here:
 https://github.com/xdp-project/xdp-project/blob/master/areas/cpumap/cpumap03-optimizations.org

Performance measurements can be considered micro benchmarks, as they measure
dropping packets at different stages in the network stack.
Summary based on above:

Baseline benchmarks
- baseline-redirect: UdpNoPorts: 3,180,074
- baseline-redirect: iptables-raw drop: 6,193,534

Patch1: bpf: cpumap use ptr_ring_consume_batched
- redirect: UdpNoPorts: 3,327,729
- redirect: iptables-raw drop: 6,321,540

Patch2: net: core: introduce build_skb_around
- redirect: UdpNoPorts: 3,221,303
- redirect: iptables-raw drop: 6,320,066

Patch3: bpf: cpumap do bulk allocation of SKBs
- redirect: UdpNoPorts: 3,290,563
- redirect: iptables-raw drop: 6,650,112

Patch4: bpf: cpumap memory prefetchw optimizations for struct page
- redirect: UdpNoPorts: 3,520,250
- redirect: iptables-raw drop: 7,649,604

In this V2 submission I have chosen drop the SKB-list patch using
netif_receive_skb_list() as it was not showing a performance improvement for
these micro benchmarks.
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>