From c10d9310edf5aa4a676991139d1a43ec7d87e56b Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 29 Apr 2016 14:16:47 -0700 Subject: 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 Acked-by: Soheil Hassas Yeganeh Signed-off-by: David S. Miller --- net/ipv4/tcp_fastopen.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'net/ipv4/tcp_fastopen.c') diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c index a1498d507e42..54d9f9b0120f 100644 --- a/net/ipv4/tcp_fastopen.c +++ b/net/ipv4/tcp_fastopen.c @@ -255,9 +255,9 @@ static bool tcp_fastopen_queue_check(struct sock *sk) spin_lock(&fastopenq->lock); req1 = fastopenq->rskq_rst_head; if (!req1 || time_after(req1->rsk_timer.expires, jiffies)) { - spin_unlock(&fastopenq->lock); __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENLISTENOVERFLOW); + spin_unlock(&fastopenq->lock); return false; } fastopenq->rskq_rst_head = req1->dl_next; @@ -282,7 +282,7 @@ struct sock *tcp_try_fastopen(struct sock *sk, struct sk_buff *skb, struct sock *child; if (foc->len == 0) /* Client requests a cookie */ - __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENCOOKIEREQD); + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENCOOKIEREQD); if (!((sysctl_tcp_fastopen & TFO_SERVER_ENABLE) && (syn_data || foc->len >= 0) && @@ -311,13 +311,13 @@ fastopen: child = tcp_fastopen_create_child(sk, skb, dst, req); if (child) { foc->len = -1; - __NET_INC_STATS(sock_net(sk), - LINUX_MIB_TCPFASTOPENPASSIVE); + NET_INC_STATS(sock_net(sk), + LINUX_MIB_TCPFASTOPENPASSIVE); return child; } - __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENPASSIVEFAIL); + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENPASSIVEFAIL); } else if (foc->len > 0) /* Client presents an invalid cookie */ - __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENPASSIVEFAIL); + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENPASSIVEFAIL); valid_foc.exp = foc->exp; *foc = valid_foc; -- cgit v1.2.3