tcp: do not assume TCP code is non preemptible
commitc10d9310edf5aa4a676991139d1a43ec7d87e56b
authorEric Dumazet <edumazet@google.com>
Fri, 29 Apr 2016 21:16:47 +0000 (29 14:16 -0700)
committerDavid S. Miller <davem@davemloft.net>
Mon, 2 May 2016 21:02:25 +0000 (2 17:02 -0400)
tree8ba2a9ec1a83011976369f96481220cd7945eab6
parent5e59c83f2335d634946e1a4fe7bc1e921930f132
tcp: do not assume TCP code is non preemptible

We want to to make TCP stack preemptible, as draining prequeue
and backlog queues can take lot of time.

Many SNMP updates were assuming that BH (and preemption) was disabled.

Need to convert some __NET_INC_STATS() calls to NET_INC_STATS()
and some __TCP_INC_STATS() to TCP_INC_STATS()

Before using this_cpu_ptr(net->ipv4.tcp_sk) in tcp_v4_send_reset()
and tcp_v4_send_ack(), we add an explicit preempt disabled section.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/ipv4/tcp.c
net/ipv4/tcp_cdg.c
net/ipv4/tcp_cubic.c
net/ipv4/tcp_fastopen.c
net/ipv4/tcp_input.c
net/ipv4/tcp_ipv4.c
net/ipv4/tcp_minisocks.c
net/ipv4/tcp_output.c
net/ipv4/tcp_recovery.c
net/ipv4/tcp_timer.c
net/ipv6/tcp_ipv6.c