Merge branch 'tcp-preempt'

Eric Dumazet says:

====================
net: make TCP preemptible

Most of TCP stack assumed it was running from BH handler.

This is great for most things, as TCP behavior is very sensitive
to scheduling artifacts.

However, the prequeue and backlog processing are problematic,
as they need to be flushed with BH being blocked.

To cope with modern needs, TCP sockets have big sk_rcvbuf values,
in the order of 16 MB, and soon 32 MB.
This means that backlog can hold thousands of packets, and things
like TCP coalescing or collapsing on this amount of packets can
lead to insane latency spikes, since BH are blocked for too long.

It is time to make UDP/TCP stacks preemptible.

Note that fast path still runs from BH handler.

v2: Added "tcp: make tcp_sendmsg() aware of socket backlog"
    to reduce latency problems of large sends.

v3: Fixed a typo in tcp_cdg.c
====================

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

19 files changed, 139 insertions, 157 deletions

diff --git a/net/core/sock.c b/net/core/sock.c
index e16a5db853c6..f615e9391170 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -2019,33 +2019,27 @@ static void __release_sock(struct sock *sk)
 	__releases(&sk->sk_lock.slock)
 	__acquires(&sk->sk_lock.slock)
 {
-	struct sk_buff *skb = sk->sk_backlog.head;
+	struct sk_buff *skb, *next;
 
-	do {
+	while ((skb = sk->sk_backlog.head) != NULL) {
 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
-		bh_unlock_sock(sk);
 
-		do {
-			struct sk_buff *next = skb->next;
+		spin_unlock_bh(&sk->sk_lock.slock);
 
+		do {
+			next = skb->next;
 			prefetch(next);
 			WARN_ON_ONCE(skb_dst_is_noref(skb));
 			skb->next = NULL;
 			sk_backlog_rcv(sk, skb);
 
-			/*
-			 * We are in process context here with softirqs
-			 * disabled, use cond_resched_softirq() to preempt.
-			 * This is safe to do because we've taken the backlog
-			 * queue private:
-			 */
-			cond_resched_softirq();
+			cond_resched();
 
 			skb = next;
 		} while (skb != NULL);
 
-		bh_lock_sock(sk);
-	} while ((skb = sk->sk_backlog.head) != NULL);
+		spin_lock_bh(&sk->sk_lock.slock);
+	}
 
 	/*
 	 * Doing the zeroing here guarantee we can not loop forever
@@ -2054,6 +2048,13 @@ static void __release_sock(struct sock *sk)
 	sk->sk_backlog.len = 0;
 }
 
+void __sk_flush_backlog(struct sock *sk)
+{
+	spin_lock_bh(&sk->sk_lock.slock);
+	__release_sock(sk);
+	spin_unlock_bh(&sk->sk_lock.slock);
+}
+
 /**
  * sk_wait_data - wait for data to arrive at sk_receive_queue
  * @sk:    sock to wait on
diff --git a/net/dccp/input.c b/net/dccp/input.c
index 2437ecc13b82..ba347184bda9 100644
--- a/net/dccp/input.c
+++ b/net/dccp/input.c
@@ -359,7 +359,7 @@ send_sync:
 		goto discard;
 	}
 
-	__DCCP_INC_STATS(DCCP_MIB_INERRS);
+	DCCP_INC_STATS(DCCP_MIB_INERRS);
 discard:
 	__kfree_skb(skb);
 	return 0;
diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index a8164272e0f4..5c7e413a3ae4 100644
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -533,8 +533,8 @@ static void dccp_v4_ctl_send_reset(const struct sock *sk, struct sk_buff *rxskb)
 	bh_unlock_sock(ctl_sk);
 
 	if (net_xmit_eval(err) == 0) {
-		__DCCP_INC_STATS(DCCP_MIB_OUTSEGS);
-		__DCCP_INC_STATS(DCCP_MIB_OUTRSTS);
+		DCCP_INC_STATS(DCCP_MIB_OUTSEGS);
+		DCCP_INC_STATS(DCCP_MIB_OUTRSTS);
 	}
 out:
 	 dst_release(dst);
diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index 0f4eb4ea57a5..d176f4e66369 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -277,8 +277,8 @@ static void dccp_v6_ctl_send_reset(const struct sock *sk, struct sk_buff *rxskb)
 	if (!IS_ERR(dst)) {
 		skb_dst_set(skb, dst);
 		ip6_xmit(ctl_sk, skb, &fl6, NULL, 0);
-		__DCCP_INC_STATS(DCCP_MIB_OUTSEGS);
-		__DCCP_INC_STATS(DCCP_MIB_OUTRSTS);
+		DCCP_INC_STATS(DCCP_MIB_OUTSEGS);
+		DCCP_INC_STATS(DCCP_MIB_OUTRSTS);
 		return;
 	}
 
diff --git a/net/dccp/options.c b/net/dccp/options.c
index b82b7ee9a1d2..74d29c56c367 100644
--- a/net/dccp/options.c
+++ b/net/dccp/options.c
@@ -253,7 +253,7 @@ out_nonsensical_length:
 	return 0;
 
 out_invalid_option:
-	__DCCP_INC_STATS(DCCP_MIB_INVALIDOPT);
+	DCCP_INC_STATS(DCCP_MIB_INVALIDOPT);
 	rc = DCCP_RESET_CODE_OPTION_ERROR;
 out_featneg_failed:
 	DCCP_WARN("DCCP(%p): Option %d (len=%d) error=%u\n", sk, opt, len, rc);
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index cb4d1cabb42c..b945c2b046c5 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1136,11 +1136,12 @@ int tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
 	/* This should be in poll */
 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
 
-	mss_now = tcp_send_mss(sk, &size_goal, flags);
-
 	/* Ok commence sending. */
 	copied = 0;
 
+restart:
+	mss_now = tcp_send_mss(sk, &size_goal, flags);
+
 	err = -EPIPE;
 	if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
 		goto out_err;
@@ -1166,6 +1167,9 @@ new_segment:
 			if (!sk_stream_memory_free(sk))
 				goto wait_for_sndbuf;
 
+			if (sk_flush_backlog(sk))
+				goto restart;
+
 			skb = sk_stream_alloc_skb(sk,
 						  select_size(sk, sg),
 						  sk->sk_allocation,
@@ -1449,12 +1453,8 @@ static void tcp_prequeue_process(struct sock *sk)
 
 	NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPPREQUEUED);
 
-	/* RX process wants to run with disabled BHs, though it is not
-	 * necessary */
-	local_bh_disable();
 	while ((skb = __skb_dequeue(&tp->ucopy.prequeue)) != NULL)
 		sk_backlog_rcv(sk, skb);
-	local_bh_enable();
 
 	/* Clear memory counter. */
 	tp->ucopy.memory = 0;
@@ -3095,7 +3095,7 @@ void tcp_done(struct sock *sk)
 	struct request_sock *req = tcp_sk(sk)->fastopen_rsk;
 
 	if (sk->sk_state == TCP_SYN_SENT || sk->sk_state == TCP_SYN_RECV)
-		__TCP_INC_STATS(sock_net(sk), TCP_MIB_ATTEMPTFAILS);
+		TCP_INC_STATS(sock_net(sk), TCP_MIB_ATTEMPTFAILS);
 
 	tcp_set_state(sk, TCP_CLOSE);
 	tcp_clear_xmit_timers(sk);
diff --git a/net/ipv4/tcp_cdg.c b/net/ipv4/tcp_cdg.c
index 3c00208c37f4..ccce8a55f1e1 100644
--- a/net/ipv4/tcp_cdg.c
+++ b/net/ipv4/tcp_cdg.c
@@ -155,11 +155,11 @@ static void tcp_cdg_hystart_update(struct sock *sk)
 
 			ca->last_ack = now_us;
 			if (after(now_us, ca->round_start + base_owd)) {
-				__NET_INC_STATS(sock_net(sk),
-						LINUX_MIB_TCPHYSTARTTRAINDETECT);
-				__NET_ADD_STATS(sock_net(sk),
-						LINUX_MIB_TCPHYSTARTTRAINCWND,
-						tp->snd_cwnd);
+				NET_INC_STATS(sock_net(sk),
+					      LINUX_MIB_TCPHYSTARTTRAINDETECT);
+				NET_ADD_STATS(sock_net(sk),
+					      LINUX_MIB_TCPHYSTARTTRAINCWND,
+					      tp->snd_cwnd);
 				tp->snd_ssthresh = tp->snd_cwnd;
 				return;
 			}
@@ -174,11 +174,11 @@ static void tcp_cdg_hystart_update(struct sock *sk)
 					 125U);
 
 			if (ca->rtt.min > thresh) {
-				__NET_INC_STATS(sock_net(sk),
-						LINUX_MIB_TCPHYSTARTDELAYDETECT);
-				__NET_ADD_STATS(sock_net(sk),
-						LINUX_MIB_TCPHYSTARTDELAYCWND,
-						tp->snd_cwnd);
+				NET_INC_STATS(sock_net(sk),
+					      LINUX_MIB_TCPHYSTARTDELAYDETECT);
+				NET_ADD_STATS(sock_net(sk),
+					      LINUX_MIB_TCPHYSTARTDELAYCWND,
+					      tp->snd_cwnd);
 				tp->snd_ssthresh = tp->snd_cwnd;
 			}
 		}
diff --git a/net/ipv4/tcp_cubic.c b/net/ipv4/tcp_cubic.c
index 59155af9de5d..0ce946e395e1 100644
--- a/net/ipv4/tcp_cubic.c
+++ b/net/ipv4/tcp_cubic.c
@@ -402,11 +402,11 @@ static void hystart_update(struct sock *sk, u32 delay)
 			ca->last_ack = now;
 			if ((s32)(now - ca->round_start) > ca->delay_min >> 4) {
 				ca->found |= HYSTART_ACK_TRAIN;
-				__NET_INC_STATS(sock_net(sk),
-						LINUX_MIB_TCPHYSTARTTRAINDETECT);
-				__NET_ADD_STATS(sock_net(sk),
-						LINUX_MIB_TCPHYSTARTTRAINCWND,
-						tp->snd_cwnd);
+				NET_INC_STATS(sock_net(sk),
+					      LINUX_MIB_TCPHYSTARTTRAINDETECT);
+				NET_ADD_STATS(sock_net(sk),
+					      LINUX_MIB_TCPHYSTARTTRAINCWND,
+					      tp->snd_cwnd);
 				tp->snd_ssthresh = tp->snd_cwnd;
 			}
 		}
@@ -423,11 +423,11 @@ static void hystart_update(struct sock *sk, u32 delay)
 			if (ca->curr_rtt > ca->delay_min +
 			    HYSTART_DELAY_THRESH(ca->delay_min >> 3)) {
 				ca->found |= HYSTART_DELAY;
-				__NET_INC_STATS(sock_net(sk),
-						LINUX_MIB_TCPHYSTARTDELAYDETECT);
-				__NET_ADD_STATS(sock_net(sk),
-						LINUX_MIB_TCPHYSTARTDELAYCWND,
-						tp->snd_cwnd);
+				NET_INC_STATS(sock_net(sk),
+					      LINUX_MIB_TCPHYSTARTDELAYDETECT);
+				NET_ADD_STATS(sock_net(sk),
+					      LINUX_MIB_TCPHYSTARTDELAYCWND,
+					      tp->snd_cwnd);
 				tp->snd_ssthresh = tp->snd_cwnd;
 			}
 		}
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;
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 1fb19c91e091..6171f92be090 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -869,7 +869,7 @@ static void tcp_update_reordering(struct sock *sk, const int metric,
 		else
 			mib_idx = LINUX_MIB_TCPSACKREORDER;
 
-		__NET_INC_STATS(sock_net(sk), mib_idx);
+		NET_INC_STATS(sock_net(sk), mib_idx);
 #if FASTRETRANS_DEBUG > 1
 		pr_debug("Disorder%d %d %u f%u s%u rr%d\n",
 			 tp->rx_opt.sack_ok, inet_csk(sk)->icsk_ca_state,
@@ -1062,7 +1062,7 @@ static bool tcp_check_dsack(struct sock *sk, const struct sk_buff *ack_skb,
 	if (before(start_seq_0, TCP_SKB_CB(ack_skb)->ack_seq)) {
 		dup_sack = true;
 		tcp_dsack_seen(tp);
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPDSACKRECV);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPDSACKRECV);
 	} else if (num_sacks > 1) {
 		u32 end_seq_1 = get_unaligned_be32(&sp[1].end_seq);
 		u32 start_seq_1 = get_unaligned_be32(&sp[1].start_seq);
@@ -1071,7 +1071,7 @@ static bool tcp_check_dsack(struct sock *sk, const struct sk_buff *ack_skb,
 		    !before(start_seq_0, start_seq_1)) {
 			dup_sack = true;
 			tcp_dsack_seen(tp);
-			__NET_INC_STATS(sock_net(sk),
+			NET_INC_STATS(sock_net(sk),
 					LINUX_MIB_TCPDSACKOFORECV);
 		}
 	}
@@ -1289,7 +1289,7 @@ static bool tcp_shifted_skb(struct sock *sk, struct sk_buff *skb,
 
 	if (skb->len > 0) {
 		BUG_ON(!tcp_skb_pcount(skb));
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_SACKSHIFTED);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_SACKSHIFTED);
 		return false;
 	}
 
@@ -1314,7 +1314,7 @@ static bool tcp_shifted_skb(struct sock *sk, struct sk_buff *skb,
 	tcp_unlink_write_queue(skb, sk);
 	sk_wmem_free_skb(sk, skb);
 
-	__NET_INC_STATS(sock_net(sk), LINUX_MIB_SACKMERGED);
+	NET_INC_STATS(sock_net(sk), LINUX_MIB_SACKMERGED);
 
 	return true;
 }
@@ -1473,7 +1473,7 @@ noop:
 	return skb;
 
 fallback:
-	__NET_INC_STATS(sock_net(sk), LINUX_MIB_SACKSHIFTFALLBACK);
+	NET_INC_STATS(sock_net(sk), LINUX_MIB_SACKSHIFTFALLBACK);
 	return NULL;
 }
 
@@ -1661,7 +1661,7 @@ tcp_sacktag_write_queue(struct sock *sk, const struct sk_buff *ack_skb,
 				mib_idx = LINUX_MIB_TCPSACKDISCARD;
 			}
 
-			__NET_INC_STATS(sock_net(sk), mib_idx);
+			NET_INC_STATS(sock_net(sk), mib_idx);
 			if (i == 0)
 				first_sack_index = -1;
 			continue;
@@ -1913,7 +1913,7 @@ void tcp_enter_loss(struct sock *sk)
 	skb = tcp_write_queue_head(sk);
 	is_reneg = skb && (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED);
 	if (is_reneg) {
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSACKRENEGING);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSACKRENEGING);
 		tp->sacked_out = 0;
 		tp->fackets_out = 0;
 	}
@@ -2399,7 +2399,7 @@ static bool tcp_try_undo_recovery(struct sock *sk)
 		else
 			mib_idx = LINUX_MIB_TCPFULLUNDO;
 
-		__NET_INC_STATS(sock_net(sk), mib_idx);
+		NET_INC_STATS(sock_net(sk), mib_idx);
 	}
 	if (tp->snd_una == tp->high_seq && tcp_is_reno(tp)) {
 		/* Hold old state until something *above* high_seq
@@ -2421,7 +2421,7 @@ static bool tcp_try_undo_dsack(struct sock *sk)
 	if (tp->undo_marker && !tp->undo_retrans) {
 		DBGUNDO(sk, "D-SACK");
 		tcp_undo_cwnd_reduction(sk, false);
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPDSACKUNDO);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPDSACKUNDO);
 		return true;
 	}
 	return false;
@@ -2436,9 +2436,9 @@ static bool tcp_try_undo_loss(struct sock *sk, bool frto_undo)
 		tcp_undo_cwnd_reduction(sk, true);
 
 		DBGUNDO(sk, "partial loss");
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPLOSSUNDO);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPLOSSUNDO);
 		if (frto_undo)
-			__NET_INC_STATS(sock_net(sk),
+			NET_INC_STATS(sock_net(sk),
 					LINUX_MIB_TCPSPURIOUSRTOS);
 		inet_csk(sk)->icsk_retransmits = 0;
 		if (frto_undo || tcp_is_sack(tp))
@@ -2563,7 +2563,7 @@ static void tcp_mtup_probe_failed(struct sock *sk)
 
 	icsk->icsk_mtup.search_high = icsk->icsk_mtup.probe_size - 1;
 	icsk->icsk_mtup.probe_size = 0;
-	__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMTUPFAIL);
+	NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMTUPFAIL);
 }
 
 static void tcp_mtup_probe_success(struct sock *sk)
@@ -2583,7 +2583,7 @@ static void tcp_mtup_probe_success(struct sock *sk)
 	icsk->icsk_mtup.search_low = icsk->icsk_mtup.probe_size;
 	icsk->icsk_mtup.probe_size = 0;
 	tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
-	__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMTUPSUCCESS);
+	NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMTUPSUCCESS);
 }
 
 /* Do a simple retransmit without using the backoff mechanisms in
@@ -2647,7 +2647,7 @@ static void tcp_enter_recovery(struct sock *sk, bool ece_ack)
 	else
 		mib_idx = LINUX_MIB_TCPSACKRECOVERY;
 
-	__NET_INC_STATS(sock_net(sk), mib_idx);
+	NET_INC_STATS(sock_net(sk), mib_idx);
 
 	tp->prior_ssthresh = 0;
 	tcp_init_undo(tp);
@@ -2740,7 +2740,7 @@ static bool tcp_try_undo_partial(struct sock *sk, const int acked)
 
 		DBGUNDO(sk, "partial recovery");
 		tcp_undo_cwnd_reduction(sk, true);
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPPARTIALUNDO);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPPARTIALUNDO);
 		tcp_try_keep_open(sk);
 		return true;
 	}
@@ -3434,7 +3434,7 @@ bool tcp_oow_rate_limited(struct net *net, const struct sk_buff *skb,
 		s32 elapsed = (s32)(tcp_time_stamp - *last_oow_ack_time);
 
 		if (0 <= elapsed && elapsed < sysctl_tcp_invalid_ratelimit) {
-			__NET_INC_STATS(net, mib_idx);
+			NET_INC_STATS(net, mib_idx);
 			return true;	/* rate-limited: don't send yet! */
 		}
 	}
@@ -3467,7 +3467,7 @@ static void tcp_send_challenge_ack(struct sock *sk, const struct sk_buff *skb)
 		challenge_count = 0;
 	}
 	if (++challenge_count <= sysctl_tcp_challenge_ack_limit) {
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPCHALLENGEACK);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPCHALLENGEACK);
 		tcp_send_ack(sk);
 	}
 }
@@ -3516,7 +3516,7 @@ static void tcp_process_tlp_ack(struct sock *sk, u32 ack, int flag)
 		tcp_set_ca_state(sk, TCP_CA_CWR);
 		tcp_end_cwnd_reduction(sk);
 		tcp_try_keep_open(sk);
-		__NET_INC_STATS(sock_net(sk),
+		NET_INC_STATS(sock_net(sk),
 				LINUX_MIB_TCPLOSSPROBERECOVERY);
 	} else if (!(flag & (FLAG_SND_UNA_ADVANCED |
 			     FLAG_NOT_DUP | FLAG_DATA_SACKED))) {
@@ -3621,14 +3621,14 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 
 		tcp_in_ack_event(sk, CA_ACK_WIN_UPDATE);
 
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPHPACKS);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPHPACKS);
 	} else {
 		u32 ack_ev_flags = CA_ACK_SLOWPATH;
 
 		if (ack_seq != TCP_SKB_CB(skb)->end_seq)
 			flag |= FLAG_DATA;
 		else
-			__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPPUREACKS);
+			NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPPUREACKS);
 
 		flag |= tcp_ack_update_window(sk, skb, ack, ack_seq);
 
@@ -4131,7 +4131,7 @@ static void tcp_dsack_set(struct sock *sk, u32 seq, u32 end_seq)
 		else
 			mib_idx = LINUX_MIB_TCPDSACKOFOSENT;
 
-		__NET_INC_STATS(sock_net(sk), mib_idx);
+		NET_INC_STATS(sock_net(sk), mib_idx);
 
 		tp->rx_opt.dsack = 1;
 		tp->duplicate_sack[0].start_seq = seq;
@@ -4155,7 +4155,7 @@ static void tcp_send_dupack(struct sock *sk, const struct sk_buff *skb)
 
 	if (TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq &&
 	    before(TCP_SKB_CB(skb)->seq, tp->rcv_nxt)) {
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKLOST);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKLOST);
 		tcp_enter_quickack_mode(sk);
 
 		if (tcp_is_sack(tp) && sysctl_tcp_dsack) {
@@ -4305,7 +4305,7 @@ static bool tcp_try_coalesce(struct sock *sk,
 
 	atomic_add(delta, &sk->sk_rmem_alloc);
 	sk_mem_charge(sk, delta);
-	__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRCVCOALESCE);
+	NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRCVCOALESCE);
 	TCP_SKB_CB(to)->end_seq = TCP_SKB_CB(from)->end_seq;
 	TCP_SKB_CB(to)->ack_seq = TCP_SKB_CB(from)->ack_seq;
 	TCP_SKB_CB(to)->tcp_flags |= TCP_SKB_CB(from)->tcp_flags;
@@ -4393,7 +4393,7 @@ static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb)
 	tcp_ecn_check_ce(tp, skb);
 
 	if (unlikely(tcp_try_rmem_schedule(sk, skb, skb->truesize))) {
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFODROP);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFODROP);
 		tcp_drop(sk, skb);
 		return;
 	}
@@ -4402,7 +4402,7 @@ static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb)
 	tp->pred_flags = 0;
 	inet_csk_schedule_ack(sk);
 
-	__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFOQUEUE);
+	NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFOQUEUE);
 	SOCK_DEBUG(sk, "out of order segment: rcv_next %X seq %X - %X\n",
 		   tp->rcv_nxt, TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq);
 
@@ -4457,7 +4457,7 @@ static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb)
 	if (skb1 && before(seq, TCP_SKB_CB(skb1)->end_seq)) {
 		if (!after(end_seq, TCP_SKB_CB(skb1)->end_seq)) {
 			/* All the bits are present. Drop. */
-			__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFOMERGE);
+			NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFOMERGE);
 			tcp_drop(sk, skb);
 			skb = NULL;
 			tcp_dsack_set(sk, seq, end_seq);
@@ -4496,7 +4496,7 @@ static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb)
 		__skb_unlink(skb1, &tp->out_of_order_queue);
 		tcp_dsack_extend(sk, TCP_SKB_CB(skb1)->seq,
 				 TCP_SKB_CB(skb1)->end_seq);
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFOMERGE);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFOMERGE);
 		tcp_drop(sk, skb1);
 	}
 
@@ -4611,14 +4611,12 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb)
 
 			__set_current_state(TASK_RUNNING);
 
-			local_bh_enable();
 			if (!skb_copy_datagram_msg(skb, 0, tp->ucopy.msg, chunk)) {
 				tp->ucopy.len -= chunk;
 				tp->copied_seq += chunk;
 				eaten = (chunk == skb->len);
 				tcp_rcv_space_adjust(sk);
 			}
-			local_bh_disable();
 		}
 
 		if (eaten <= 0) {
@@ -4661,7 +4659,7 @@ queue_and_out:
 
 	if (!after(TCP_SKB_CB(skb)->end_seq, tp->rcv_nxt)) {
 		/* A retransmit, 2nd most common case.  Force an immediate ack. */
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKLOST);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKLOST);
 		tcp_dsack_set(sk, TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq);
 
 out_of_window:
@@ -4707,7 +4705,7 @@ static struct sk_buff *tcp_collapse_one(struct sock *sk, struct sk_buff *skb,
 
 	__skb_unlink(skb, list);
 	__kfree_skb(skb);
-	__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRCVCOLLAPSED);
+	NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRCVCOLLAPSED);
 
 	return next;
 }
@@ -4866,7 +4864,7 @@ static bool tcp_prune_ofo_queue(struct sock *sk)
 	bool res = false;
 
 	if (!skb_queue_empty(&tp->out_of_order_queue)) {
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_OFOPRUNED);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_OFOPRUNED);
 		__skb_queue_purge(&tp->out_of_order_queue);
 
 		/* Reset SACK state.  A conforming SACK implementation will
@@ -4895,7 +4893,7 @@ static int tcp_prune_queue(struct sock *sk)
 
 	SOCK_DEBUG(sk, "prune_queue: c=%x\n", tp->copied_seq);
 
-	__NET_INC_STATS(sock_net(sk), LINUX_MIB_PRUNECALLED);
+	NET_INC_STATS(sock_net(sk), LINUX_MIB_PRUNECALLED);
 
 	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
 		tcp_clamp_window(sk);
@@ -4925,7 +4923,7 @@ static int tcp_prune_queue(struct sock *sk)
 	 * drop receive data on the floor.  It will get retransmitted
 	 * and hopefully then we'll have sufficient space.
 	 */
-	__NET_INC_STATS(sock_net(sk), LINUX_MIB_RCVPRUNED);
+	NET_INC_STATS(sock_net(sk), LINUX_MIB_RCVPRUNED);
 
 	/* Massive buffer overcommit. */
 	tp->pred_flags = 0;
@@ -5134,7 +5132,6 @@ static int tcp_copy_to_iovec(struct sock *sk, struct sk_buff *skb, int hlen)
 	int chunk = skb->len - hlen;
 	int err;
 
-	local_bh_enable();
 	if (skb_csum_unnecessary(skb))
 		err = skb_copy_datagram_msg(skb, hlen, tp->ucopy.msg, chunk);
 	else
@@ -5146,32 +5143,9 @@ static int tcp_copy_to_iovec(struct sock *sk, struct sk_buff *skb, int hlen)
 		tcp_rcv_space_adjust(sk);
 	}
 
-	local_bh_disable();
 	return err;
 }
 
-static __sum16 __tcp_checksum_complete_user(struct sock *sk,
-					    struct sk_buff *skb)
-{
-	__sum16 result;
-
-	if (sock_owned_by_user(sk)) {
-		local_bh_enable();
-		result = __tcp_checksum_complete(skb);
-		local_bh_disable();
-	} else {
-		result = __tcp_checksum_complete(skb);
-	}
-	return result;
-}
-
-static inline bool tcp_checksum_complete_user(struct sock *sk,
-					     struct sk_buff *skb)
-{
-	return !skb_csum_unnecessary(skb) &&
-	       __tcp_checksum_complete_user(sk, skb);
-}
-
 /* Does PAWS and seqno based validation of an incoming segment, flags will
  * play significant role here.
  */
@@ -5184,7 +5158,7 @@ static bool tcp_validate_incoming(struct sock *sk, struct sk_buff *skb,
 	if (tcp_fast_parse_options(skb, th, tp) && tp->rx_opt.saw_tstamp &&
 	    tcp_paws_discard(sk, skb)) {
 		if (!th->rst) {
-			__NET_INC_STATS(sock_net(sk), LINUX_MIB_PAWSESTABREJECTED);
+			NET_INC_STATS(sock_net(sk), LINUX_MIB_PAWSESTABREJECTED);
 			if (!tcp_oow_rate_limited(sock_net(sk), skb,
 						  LINUX_MIB_TCPACKSKIPPEDPAWS,
 						  &tp->last_oow_ack_time))
@@ -5236,8 +5210,8 @@ static bool tcp_validate_incoming(struct sock *sk, struct sk_buff *skb,
 	if (th->syn) {
 syn_challenge:
 		if (syn_inerr)
-			__TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS);
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSYNCHALLENGE);
+			TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSYNCHALLENGE);
 		tcp_send_challenge_ack(sk, skb);
 		goto discard;
 	}
@@ -5352,7 +5326,7 @@ void tcp_rcv_established(struct sock *sk, struct sk_buff *skb,
 				tcp_data_snd_check(sk);
 				return;
 			} else { /* Header too small */
-				__TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS);
+				TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS);
 				goto discard;
 			}
 		} else {
@@ -5380,13 +5354,13 @@ void tcp_rcv_established(struct sock *sk, struct sk_buff *skb,
 
 					__skb_pull(skb, tcp_header_len);
 					tcp_rcv_nxt_update(tp, TCP_SKB_CB(skb)->end_seq);
-					__NET_INC_STATS(sock_net(sk),
+					NET_INC_STATS(sock_net(sk),
 							LINUX_MIB_TCPHPHITSTOUSER);
 					eaten = 1;
 				}
 			}
 			if (!eaten) {
-				if (tcp_checksum_complete_user(sk, skb))
+				if (tcp_checksum_complete(skb))
 					goto csum_error;
 
 				if ((int)skb->truesize > sk->sk_forward_alloc)
@@ -5403,7 +5377,7 @@ void tcp_rcv_established(struct sock *sk, struct sk_buff *skb,
 
 				tcp_rcv_rtt_measure_ts(sk, skb);
 
-				__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPHPHITS);
+				NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPHPHITS);
 
 				/* Bulk data transfer: receiver */
 				eaten = tcp_queue_rcv(sk, skb, tcp_header_len,
@@ -5430,7 +5404,7 @@ no_ack:
 	}
 
 slow_path:
-	if (len < (th->doff << 2) || tcp_checksum_complete_user(sk, skb))
+	if (len < (th->doff << 2) || tcp_checksum_complete(skb))
 		goto csum_error;
 
 	if (!th->ack && !th->rst && !th->syn)
@@ -5460,8 +5434,8 @@ step5:
 	return;
 
 csum_error:
-	__TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS);
-	__TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS);
+	TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS);
+	TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS);
 
 discard:
 	tcp_drop(sk, skb);
@@ -5553,13 +5527,13 @@ static bool tcp_rcv_fastopen_synack(struct sock *sk, struct sk_buff *synack,
 				break;
 		}
 		tcp_rearm_rto(sk);
-		__NET_INC_STATS(sock_net(sk),
+		NET_INC_STATS(sock_net(sk),
 				LINUX_MIB_TCPFASTOPENACTIVEFAIL);
 		return true;
 	}
 	tp->syn_data_acked = tp->syn_data;
 	if (tp->syn_data_acked)
-		__NET_INC_STATS(sock_net(sk),
+		NET_INC_STATS(sock_net(sk),
 				LINUX_MIB_TCPFASTOPENACTIVE);
 
 	tcp_fastopen_add_skb(sk, synack);
@@ -5595,7 +5569,7 @@ static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb,
 		if (tp->rx_opt.saw_tstamp && tp->rx_opt.rcv_tsecr &&
 		    !between(tp->rx_opt.rcv_tsecr, tp->retrans_stamp,
 			     tcp_time_stamp)) {
-			__NET_INC_STATS(sock_net(sk),
+			NET_INC_STATS(sock_net(sk),
 					LINUX_MIB_PAWSACTIVEREJECTED);
 			goto reset_and_undo;
 		}
@@ -5965,7 +5939,7 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb)
 		    (TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq &&
 		     after(TCP_SKB_CB(skb)->end_seq - th->fin, tp->rcv_nxt))) {
 			tcp_done(sk);
-			__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONDATA);
+			NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONDATA);
 			return 1;
 		}
 
@@ -6022,7 +5996,7 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb)
 		if (sk->sk_shutdown & RCV_SHUTDOWN) {
 			if (TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq &&
 			    after(TCP_SKB_CB(skb)->end_seq - th->fin, tp->rcv_nxt)) {
-				__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONDATA);
+				NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONDATA);
 				tcp_reset(sk);
 				return 1;
 			}
@@ -6224,7 +6198,7 @@ int tcp_conn_request(struct request_sock_ops *rsk_ops,
 	 * timeout.
 	 */
 	if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) {
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
 		goto drop;
 	}
 
@@ -6271,7 +6245,7 @@ int tcp_conn_request(struct request_sock_ops *rsk_ops,
 			if (dst && strict &&
 			    !tcp_peer_is_proven(req, dst, true,
 						tmp_opt.saw_tstamp)) {
-				__NET_INC_STATS(sock_net(sk), LINUX_MIB_PAWSPASSIVEREJECTED);
+				NET_INC_STATS(sock_net(sk), LINUX_MIB_PAWSPASSIVEREJECTED);
 				goto drop_and_release;
 			}
 		}
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 87b173b563b0..761bc492c5e3 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -692,6 +692,7 @@ static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb)
 		     offsetof(struct inet_timewait_sock, tw_bound_dev_if));
 
 	arg.tos = ip_hdr(skb)->tos;
+	preempt_disable();
 	ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk),
 			      skb, &TCP_SKB_CB(skb)->header.h4.opt,
 			      ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
@@ -699,6 +700,7 @@ static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb)
 
 	__TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
 	__TCP_INC_STATS(net, TCP_MIB_OUTRSTS);
+	preempt_enable();
 
 #ifdef CONFIG_TCP_MD5SIG
 out:
@@ -774,12 +776,14 @@ static void tcp_v4_send_ack(struct net *net,
 	if (oif)
 		arg.bound_dev_if = oif;
 	arg.tos = tos;
+	preempt_disable();
 	ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk),
 			      skb, &TCP_SKB_CB(skb)->header.h4.opt,
 			      ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
 			      &arg, arg.iov[0].iov_len);
 
 	__TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
+	preempt_enable();
 }
 
 static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb)
@@ -1151,12 +1155,12 @@ static bool tcp_v4_inbound_md5_hash(const struct sock *sk,
 		return false;
 
 	if (hash_expected && !hash_location) {
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND);
 		return true;
 	}
 
 	if (!hash_expected && hash_location) {
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED);
 		return true;
 	}
 
@@ -1342,7 +1346,7 @@ struct sock *tcp_v4_syn_recv_sock(const struct sock *sk, struct sk_buff *skb,
 	return newsk;
 
 exit_overflow:
-	__NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
+	NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
 exit_nonewsk:
 	dst_release(dst);
 exit:
@@ -1432,8 +1436,8 @@ discard:
 	return 0;
 
 csum_err:
-	__TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS);
-	__TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS);
+	TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS);
+	TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS);
 	goto discard;
 }
 EXPORT_SYMBOL(tcp_v4_do_rcv);
diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index ffbfecdae471..4b95ec4ed2c8 100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -337,7 +337,7 @@ void tcp_time_wait(struct sock *sk, int state, int timeo)
 		 * socket up.  We've got bigger problems than
 		 * non-graceful socket closings.
 		 */
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPTIMEWAITOVERFLOW);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPTIMEWAITOVERFLOW);
 	}
 
 	tcp_update_metrics(sk);
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 1a487ff95d4c..25d527922b18 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -2221,14 +2221,13 @@ bool tcp_schedule_loss_probe(struct sock *sk)
 /* Thanks to skb fast clones, we can detect if a prior transmit of
  * a packet is still in a qdisc or driver queue.
  * In this case, there is very little point doing a retransmit !
- * Note: This is called from BH context only.
  */
 static bool skb_still_in_host_queue(const struct sock *sk,
 				    const struct sk_buff *skb)
 {
 	if (unlikely(skb_fclone_busy(sk, skb))) {
-		__NET_INC_STATS(sock_net(sk),
-				LINUX_MIB_TCPSPURIOUS_RTX_HOSTQUEUES);
+		NET_INC_STATS(sock_net(sk),
+			      LINUX_MIB_TCPSPURIOUS_RTX_HOSTQUEUES);
 		return true;
 	}
 	return false;
@@ -2290,7 +2289,7 @@ void tcp_send_loss_probe(struct sock *sk)
 	tp->tlp_high_seq = tp->snd_nxt;
 
 probe_sent:
-	__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPLOSSPROBES);
+	NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPLOSSPROBES);
 	/* Reset s.t. tcp_rearm_rto will restart timer from now */
 	inet_csk(sk)->icsk_pending = 0;
 rearm_timer:
@@ -2699,7 +2698,7 @@ int tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs)
 			tp->retrans_stamp = tcp_skb_timestamp(skb);
 
 	} else if (err != -EBUSY) {
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRETRANSFAIL);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRETRANSFAIL);
 	}
 
 	if (tp->undo_retrans < 0)
@@ -2823,7 +2822,7 @@ begin_fwd:
 		if (tcp_retransmit_skb(sk, skb, segs))
 			return;
 
-		__NET_INC_STATS(sock_net(sk), mib_idx);
+		NET_INC_STATS(sock_net(sk), mib_idx);
 
 		if (tcp_in_cwnd_reduction(sk))
 			tp->prr_out += tcp_skb_pcount(skb);
diff --git a/net/ipv4/tcp_recovery.c b/net/ipv4/tcp_recovery.c
index e0d0afaf15be..e36df4fcfeba 100644
--- a/net/ipv4/tcp_recovery.c
+++ b/net/ipv4/tcp_recovery.c
@@ -65,8 +65,8 @@ int tcp_rack_mark_lost(struct sock *sk)
 			if (scb->sacked & TCPCB_SACKED_RETRANS) {
 				scb->sacked &= ~TCPCB_SACKED_RETRANS;
 				tp->retrans_out -= tcp_skb_pcount(skb);
-				__NET_INC_STATS(sock_net(sk),
-						LINUX_MIB_TCPLOSTRETRANSMIT);
+				NET_INC_STATS(sock_net(sk),
+					      LINUX_MIB_TCPLOSTRETRANSMIT);
 			}
 		} else if (!(scb->sacked & TCPCB_RETRANS)) {
 			/* Original data are sent sequentially so stop early
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index 35f643d8ffbb..debdd8b33e69 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -162,8 +162,8 @@ static int tcp_write_timeout(struct sock *sk)
 			if (tp->syn_fastopen || tp->syn_data)
 				tcp_fastopen_cache_set(sk, 0, NULL, true, 0);
 			if (tp->syn_data && icsk->icsk_retransmits == 1)
-				__NET_INC_STATS(sock_net(sk),
-						LINUX_MIB_TCPFASTOPENACTIVEFAIL);
+				NET_INC_STATS(sock_net(sk),
+					      LINUX_MIB_TCPFASTOPENACTIVEFAIL);
 		}
 		retry_until = icsk->icsk_syn_retries ? : net->ipv4.sysctl_tcp_syn_retries;
 		syn_set = true;
@@ -178,8 +178,8 @@ static int tcp_write_timeout(struct sock *sk)
 			    tp->bytes_acked <= tp->rx_opt.mss_clamp) {
 				tcp_fastopen_cache_set(sk, 0, NULL, true, 0);
 				if (icsk->icsk_retransmits == net->ipv4.sysctl_tcp_retries1)
-					__NET_INC_STATS(sock_net(sk),
-							LINUX_MIB_TCPFASTOPENACTIVEFAIL);
+					NET_INC_STATS(sock_net(sk),
+						      LINUX_MIB_TCPFASTOPENACTIVEFAIL);
 			}
 			/* Black hole detection */
 			tcp_mtu_probing(icsk, sk);
@@ -209,6 +209,7 @@ static int tcp_write_timeout(struct sock *sk)
 	return 0;
 }
 
+/* Called with BH disabled */
 void tcp_delack_timer_handler(struct sock *sk)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
@@ -493,6 +494,7 @@ out_reset_timer:
 out:;
 }
 
+/* Called with BH disabled */
 void tcp_write_timer_handler(struct sock *sk)
 {
 	struct inet_connection_sock *icsk = inet_csk(sk);
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 093284c5c03b..f67f52ba4809 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1514,9 +1514,9 @@ static int __udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 
 		/* Note that an ENOMEM error is charged twice */
 		if (rc == -ENOMEM)
-			__UDP_INC_STATS(sock_net(sk), UDP_MIB_RCVBUFERRORS,
+			UDP_INC_STATS(sock_net(sk), UDP_MIB_RCVBUFERRORS,
 					is_udplite);
-		__UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
+		UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 		kfree_skb(skb);
 		trace_udp_fail_queue_rcv_skb(rc, sk);
 		return -1;
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 52914714b923..7bdc9c9c231b 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -649,12 +649,12 @@ static bool tcp_v6_inbound_md5_hash(const struct sock *sk,
 		return false;
 
 	if (hash_expected && !hash_location) {
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND);
 		return true;
 	}
 
 	if (!hash_expected && hash_location) {
-		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED);
+		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED);
 		return true;
 	}
 
@@ -825,9 +825,9 @@ static void tcp_v6_send_response(const struct sock *sk, struct sk_buff *skb, u32
 	if (!IS_ERR(dst)) {
 		skb_dst_set(buff, dst);
 		ip6_xmit(ctl_sk, buff, &fl6, NULL, tclass);
-		__TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
+		TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
 		if (rst)
-			__TCP_INC_STATS(net, TCP_MIB_OUTRSTS);
+			TCP_INC_STATS(net, TCP_MIB_OUTRSTS);
 		return;
 	}
 
@@ -1276,8 +1276,8 @@ discard:
 	kfree_skb(skb);
 	return 0;
 csum_err:
-	__TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS);
-	__TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS);
+	TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS);
+	TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS);
 	goto discard;
 
 
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 1ba5a74ac18f..f911c63f79e6 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -570,9 +570,9 @@ static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 
 		/* Note that an ENOMEM error is charged twice */
 		if (rc == -ENOMEM)
-			__UDP6_INC_STATS(sock_net(sk),
+			UDP6_INC_STATS(sock_net(sk),
 					 UDP_MIB_RCVBUFERRORS, is_udplite);
-		__UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
+		UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 		kfree_skb(skb);
 		return -1;
 	}
diff --git a/net/sctp/inqueue.c b/net/sctp/inqueue.c
index b335ffcef0b9..9d87bba0ff1d 100644
--- a/net/sctp/inqueue.c
+++ b/net/sctp/inqueue.c
@@ -89,10 +89,12 @@ void sctp_inq_push(struct sctp_inq *q, struct sctp_chunk *chunk)
 	 * Eventually, we should clean up inqueue to not rely
 	 * on the BH related data structures.
 	 */
+	local_bh_disable();
 	list_add_tail(&chunk->list, &q->in_chunk_list);
 	if (chunk->asoc)
 		chunk->asoc->stats.ipackets++;
 	q->immediate.func(&q->immediate);
+	local_bh_enable();
 }
 
 /* Peek at the next chunk on the inqeue. */