tree e3efd14c1b27eba8a65381fa769023fb9f473831
parent 25c07e2c5ec80a1c7390b41e2b03ca3d0e31fc01
author Eric Dumazet <edumazet@google.com> 1476937498 -0700
committer David S. Miller <davem@davemloft.net> 1476977072 -0400

tcp: relax listening_hash operations

softirq handlers use RCU protection to lookup listeners,
and write operations all happen from process context.
We do not need to block BH for dump operations.

Also SYN_RECV since request sockets are stored in the ehash table :

 1) inet_diag_dump_icsk() no longer need to clear
    cb->args[3] and cb->args[4] that were used as cursors while
    iterating the old per listener hash table.

 2) Also factorize a test : No need to scan listening_hash[]
    if r->id.idiag_dport is not zero.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>