Merge branch 'ipv6-sr-perf-improvements'

Merge branch 'ipv6-sr-perf-improvements'

David Lebrun says:

====================
Performances improvement for IPv6 Segment Routing

This patch series improves the performances of IPv6 SR by optimizing skb head
reallocation and extending the use of dst_cache. The overall performances improve
by 35%.

Before patch series (SRH encap):
Result: OK: 7348320(c7347271+d1048) usec, 5000000 (1000byte,0frags)
  680427pps 5443Mb/sec (5443416000bps) errors: 0

After patch series (SRH encap):
Result: OK: 4774543(c4774084+d459) usec, 5000000 (1000byte,0frags)
  1047220pps 8377Mb/sec (8377760000bps) errors: 0

Baseline for plain IPv6 forwarding:
Result: OK: 4244144(c4243722+d422) usec, 5000000 (1000byte,0frags)
  1178093pps 9424Mb/sec (9424744000bps) errors: 0
====================

Signed-off-by: David S. Miller <davem@davemloft.net>