Merge branch 'tcp_dccp_ports'

Eric Dumazet says:

====================
tcp/dccp: better use of ephemeral ports

Big servers have bloated bind table, making very hard to succeed
ephemeral port allocations, without special containers/namespace tricks.

This patch series extends the strategy added in commit 07f4c900
("tcp/dccp: try to not exhaust ip_local_port_range in connect()").

Since ports used by connect() are much likely to be shared among them,
we give a hint to both bind() and connect() to keep the crowds separated
if possible.

Of course, if on a specific host an application needs to allocate ~30000
ports using bind(), it will still be able to do so. Same for ~30000 connect()
to a unique 2-tuple (dst addr, dst port)

New implemetation is also more friendly to softirqs and reschedules.

v2: rebase after TCP SO_REUSEPORT changes
====================

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