[PATCH v5 net-next 0/4] net: low latency sockets follow ups

[Eliezer Tamir <eliezer.tamir@linux.intel.com>]

David,

Here are three clean up patches, plus one that adds a socket option for LLS.

Patch 1 converts sysctl_net_ll_poll into an unsigned int
Patch 2 converts low latency sockets to sched_clock.
Patch 3 removes the config menu for NET_LL_RX_POLL and defaults to y.
Patch 4 adds an SO_LL socket option to allow per-socket control of busy polling.

I will reply to this thread with a patch to sockperf that enables
the socket option. (unchanged from v2)

Again, thanks to everyone for their comments.

-Eliezer


Change log:
v5 
- use time_after64() instead of time_after, suggested by Eric Dumazet.

v4
- Fixed possible overflow, pointed out by Eric Dumazet.
  (reordered the patches)

v3
- Suggested by David Miller and Stephen Hemminger:
  added a patch to covert from get_cycles() to sched_clock(),
  remove dependency on X86_TSC.
- Suggested by Eric Dumazet:
  un-exported sysctl_net_ll_poll since for now it's not needed in modules.

v2
- added a patch to convert sysctl_net_ll_poll into an unsigned int.
- suggested by Eric Dimazet: treat sk_ll_usec as a u_int rather than a u_long.
- suggested by Ben Huchings: allow unprivileged user to decrease SO_LL value,
  correct return value when operation is not allowed.