* [PATCH net-next 0/6] net: make TCP preemptible
@ 2016-04-28 5:25 Eric Dumazet
2016-04-28 5:25 ` [PATCH net-next 1/6] tcp: do not assume TCP code is non preemptible Eric Dumazet
` (7 more replies)
0 siblings, 8 replies; 13+ messages in thread
From: Eric Dumazet @ 2016-04-28 5:25 UTC (permalink / raw)
To: David S . Miller; +Cc: netdev, Eric Dumazet, Eric Dumazet
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.
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.
Eric Dumazet (6):
tcp: do not assume TCP code is non preemptible
tcp: do not block bh during prequeue processing
dccp: do not assume DCCP code is non preemptible
udp: prepare for non BH masking at backlog processing
sctp: prepare for socket backlog behavior change
net: do not block BH while processing socket backlog
net/core/sock.c | 22 +++------
net/dccp/input.c | 2 +-
net/dccp/ipv4.c | 4 +-
net/dccp/ipv6.c | 4 +-
net/dccp/options.c | 2 +-
net/ipv4/tcp.c | 6 +--
net/ipv4/tcp_cdg.c | 20 ++++----
net/ipv4/tcp_cubic.c | 20 ++++----
net/ipv4/tcp_fastopen.c | 12 ++---
net/ipv4/tcp_input.c | 126 +++++++++++++++++++----------------------------
net/ipv4/tcp_ipv4.c | 14 ++++--
net/ipv4/tcp_minisocks.c | 2 +-
net/ipv4/tcp_output.c | 7 ++-
net/ipv4/tcp_recovery.c | 4 +-
net/ipv4/tcp_timer.c | 10 ++--
net/ipv4/udp.c | 4 +-
net/ipv6/tcp_ipv6.c | 12 ++---
net/ipv6/udp.c | 4 +-
net/sctp/inqueue.c | 2 +
19 files changed, 124 insertions(+), 153 deletions(-)
--
2.8.0.rc3.226.g39d4020
^ permalink raw reply [flat|nested] 13+ messages in thread
* [PATCH net-next 1/6] tcp: do not assume TCP code is non preemptible
2016-04-28 5:25 [PATCH net-next 0/6] net: make TCP preemptible Eric Dumazet
@ 2016-04-28 5:25 ` Eric Dumazet
2016-04-29 1:08 ` Eric Dumazet
2016-04-28 5:25 ` [PATCH net-next 2/6] tcp: do not block bh during prequeue processing Eric Dumazet
` (6 subsequent siblings)
7 siblings, 1 reply; 13+ messages in thread
From: Eric Dumazet @ 2016-04-28 5:25 UTC (permalink / raw)
To: David S . Miller; +Cc: netdev, Eric Dumazet, Eric Dumazet
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>
---
net/ipv4/tcp.c | 2 +-
net/ipv4/tcp_cdg.c | 20 +++++-----
net/ipv4/tcp_cubic.c | 20 +++++-----
net/ipv4/tcp_fastopen.c | 12 +++---
net/ipv4/tcp_input.c | 96 ++++++++++++++++++++++++------------------------
net/ipv4/tcp_ipv4.c | 14 ++++---
net/ipv4/tcp_minisocks.c | 2 +-
net/ipv4/tcp_output.c | 7 ++--
net/ipv4/tcp_recovery.c | 4 +-
net/ipv4/tcp_timer.c | 10 +++--
net/ipv6/tcp_ipv6.c | 12 +++---
11 files changed, 102 insertions(+), 97 deletions(-)
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 040f35e7efe0..7f51389814e6 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -3091,7 +3091,7 @@ 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..4e3007845888 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,
+ pp>>sn__cwdd);
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 0d5239c283cb..0eb31df8edfa 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;
}
@@ -1313,7 +1313,7 @@ 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;
}
@@ -1469,7 +1469,7 @@ noop:
return skb;
fallback:
- __NET_INC_STATS(sock_net(sk), LINUX_MIB_SACKSHIFTFALLBACK);
+ NET_INC_STATS(sock_net(sk), LINUX_MIB_SACKSHIFTFALLBACK);
return NULL;
}
@@ -1657,7 +1657,7 @@ 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;
@@ -1909,7 +1909,7 @@ 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;
}
@@ -2395,7 +2395,7 @@ 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
@@ -2417,7 +2417,7 @@ 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;
@@ -2432,9 +2432,9 @@ 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))
@@ -2559,7 +2559,7 @@ 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)
@@ -2579,7 +2579,7 @@ 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
@@ -2643,7 +2643,7 @@ 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);
@@ -2736,7 +2736,7 @@ 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;
}
@@ -3431,7 +3431,7 @@ 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! */
}
}
@@ -3464,7 +3464,7 @@ 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);
}
}
@@ -3513,7 +3513,7 @@ 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))) {
@@ -3618,14 +3618,14 @@ 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);
@@ -4128,7 +4128,7 @@ 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;
@@ -4152,7 +4152,7 @@ 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) {
@@ -4302,7 +4302,7 @@ 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;
@@ -4390,7 +4390,7 @@ 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;
}
@@ -4399,7 +4399,7 @@ 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);
@@ -4454,7 +4454,7 @@ 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);
@@ -4493,7 +4493,7 @@ 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);
}
@@ -4658,7 +4658,7 @@ 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:
@@ -4704,7 +4704,7 @@ 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;
}
@@ -4863,7 +4863,7 @@ 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
@@ -4892,7 +4892,7 @@ 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);
@@ -4922,7 +4922,7 @@ 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;
@@ -5181,7 +5181,7 @@ 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))
@@ -5233,8 +5233,8 @@ 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;
}
@@ -5349,7 +5349,7 @@ 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 {
@@ -5377,7 +5377,7 @@ 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;
}
@@ -5400,7 +5400,7 @@ 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,
@@ -5457,8 +5457,8 @@ 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);
@@ -5550,13 +5550,13 @@ 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);
@@ -5592,7 +5592,7 @@ 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;
}
@@ -5962,7 +5962,7 @@ 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;
}
@@ -6019,7 +6019,7 @@ 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;
}
@@ -6221,7 +6221,7 @@ 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;
}
@@ -6268,7 +6268,7 @@ 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 510f7a3c758b..fc89f2ce75f1 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 b1b2045ac3a9..411650ae3a19 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -2206,14 +2206,13 @@ 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;
@@ -2275,7 +2274,7 @@ 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:
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/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;
--
2.8.0.rc3.226.g39d4020
^ permalink raw reply related [flat|nested] 13+ messages in thread
* [PATCH net-next 2/6] tcp: do not block bh during prequeue processing
2016-04-28 5:25 [PATCH net-next 0/6] net: make TCP preemptible Eric Dumazet
2016-04-28 5:25 ` [PATCH net-next 1/6] tcp: do not assume TCP code is non preemptible Eric Dumazet
@ 2016-04-28 5:25 ` Eric Dumazet
2016-04-28 5:25 ` [PATCH net-next 3/6] dccp: do not assume DCCP code is non preemptible Eric Dumazet
` (5 subsequent siblings)
7 siblings, 0 replies; 13+ messages in thread
From: Eric Dumazet @ 2016-04-28 5:25 UTC (permalink / raw)
To: David S . Miller; +Cc: netdev, Eric Dumazet, Eric Dumazet
AFAIK, nothing in current TCP stack absolutely wants BH
being disabled once socket is owned by a thread running in
process context.
As mentioned in my prior patch ("tcp: give prequeue mode some care"),
processing a batch of packets might take time, better not block BH
at all.
Signed-off-by: Eric Dumazet <edumazet@google.com>
---
net/ipv4/tcp.c | 4 ----
net/ipv4/tcp_input.c | 30 ++----------------------------
2 files changed, 2 insertions(+), 32 deletions(-)
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 7f51389814e6..f8856b76f941 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1445,12 +1445,8 @@ 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;
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 0eb31df8edfa..44e0f9f15f32 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -4608,14 +4608,12 @@ 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) {
@@ -5131,7 +5129,6 @@ 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
@@ -5143,32 +5140,9 @@ 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.
*/
@@ -5383,7 +5357,7 @@ void tcp_rcv_established(struct sock *sk, struct sk_buff *skb,
}
}
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)
@@ -5427,7 +5401,7 @@ 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)
--
2.8.0.rc3.226.g39d4020
^ permalink raw reply related [flat|nested] 13+ messages in thread
* [PATCH net-next 3/6] dccp: do not assume DCCP code is non preemptible
2016-04-28 5:25 [PATCH net-next 0/6] net: make TCP preemptible Eric Dumazet
2016-04-28 5:25 ` [PATCH net-next 1/6] tcp: do not assume TCP code is non preemptible Eric Dumazet
2016-04-28 5:25 ` [PATCH net-next 2/6] tcp: do not block bh during prequeue processing Eric Dumazet
@ 2016-04-28 5:25 ` Eric Dumazet
2016-04-28 5:25 ` [PATCH net-next 4/6] udp: prepare for non BH masking at backlog processing Eric Dumazet
` (4 subsequent siblings)
7 siblings, 0 replies; 13+ messages in thread
From: Eric Dumazet @ 2016-04-28 5:25 UTC (permalink / raw)
To: David S . Miller; +Cc: netdev, Eric Dumazet, Eric Dumazet
DCCP uses the generic backlog code, and this will soon
be changed to not disable BH when protocol is called back.
Signed-off-by: Eric Dumazet <edumazet@google.com>
---
net/dccp/input.c | 2 +-
net/dccp/ipv4.c | 4 ++--
net/dccp/ipv6.c | 4 ++--
net/dccp/options.c | 2 +-
4 files changed, 6 insertions(+), 6 deletions(-)
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);
--
2.8.0.rc3.226.g39d4020
^ permalink raw reply related [flat|nested] 13+ messages in thread
* [PATCH net-next 4/6] udp: prepare for non BH masking at backlog processing
2016-04-28 5:25 [PATCH net-next 0/6] net: make TCP preemptible Eric Dumazet
` (2 preceding siblings ...)
2016-04-28 5:25 ` [PATCH net-next 3/6] dccp: do not assume DCCP code is non preemptible Eric Dumazet
@ 2016-04-28 5:25 ` Eric Dumazet
2016-04-28 5:25 ` [PATCH net-next 5/6] sctp: prepare for socket backlog behavior change Eric Dumazet
` (3 subsequent siblings)
7 siblings, 0 replies; 13+ messages in thread
From: Eric Dumazet @ 2016-04-28 5:25 UTC (permalink / raw)
To: David S . Miller; +Cc: netdev, Eric Dumazet, Eric Dumazet
UDP uses the generic socket backlog code, and this will soon
be changed to not disable BH when protocol is called back.
We need to use appropriate SNMP accessors.
Signed-off-by: Eric Dumazet <edumazet@google.com>
---
net/ipv4/udp.c | 4 ++--
net/ipv6/udp.c | 4 ++--
2 files changed, 4 insertions(+), 4 deletions(-)
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/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;
}
--
2.8.0.rc3.226.g39d4020
^ permalink raw reply related [flat|nested] 13+ messages in thread
* [PATCH net-next 5/6] sctp: prepare for socket backlog behavior change
2016-04-28 5:25 [PATCH net-next 0/6] net: make TCP preemptible Eric Dumazet
` (3 preceding siblings ...)
2016-04-28 5:25 ` [PATCH net-next 4/6] udp: prepare for non BH masking at backlog processing Eric Dumazet
@ 2016-04-28 5:25 ` Eric Dumazet
2016-04-28 5:25 ` [PATCH net-next 6/6] net: do not block BH while processing socket backlog Eric Dumazet
` (2 subsequent siblings)
7 siblings, 0 replies; 13+ messages in thread
From: Eric Dumazet @ 2016-04-28 5:25 UTC (permalink / raw)
To: David S . Miller; +Cc: netdev, Eric Dumazet, Eric Dumazet
sctp_inq_push() will soon be called without BH being blocked
when generic socket code flushes the socket backlog.
It is very possible SCTP can be converted to not rely on BH,
but this needs to be done by SCTP experts.
Signed-off-by: Eric Dumazet <edumazet@google.com>
---
net/sctp/inqueue.c | 2 ++
1 file changed, 2 insertions(+)
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. */
--
2.8.0.rc3.226.g39d4020
^ permalink raw reply related [flat|nested] 13+ messages in thread
* [PATCH net-next 6/6] net: do not block BH while processing socket backlog
2016-04-28 5:25 [PATCH net-next 0/6] net: make TCP preemptible Eric Dumazet
` (4 preceding siblings ...)
2016-04-28 5:25 ` [PATCH net-next 5/6] sctp: prepare for socket backlog behavior change Eric Dumazet
@ 2016-04-28 5:25 ` Eric Dumazet
2016-04-28 17:23 ` [PATCH net-next 0/6] net: make TCP preemptible Alexei Starovoitov
2016-04-28 21:18 ` Marcelo Ricardo Leitner
7 siblings, 0 replies; 13+ messages in thread
From: Eric Dumazet @ 2016-04-28 5:25 UTC (permalink / raw)
To: David S . Miller; +Cc: netdev, Eric Dumazet, Eric Dumazet
Socket backlog processing is a major latency source.
With current TCP socket sk_rcvbuf limits, I have sampled __release_sock()
holding cpu for more than 5 ms, and packets being dropped by the NIC
once ring buffer is filled.
All users are now ready to be called from process context,
we can unblock BH and let interrupts be serviced faster.
cond_resched_softirq() could be removed, as it has no more user.
Signed-off-by: Eric Dumazet <edumazet@google.com>
---
net/core/sock.c | 22 ++++++++--------------
1 file changed, 8 insertions(+), 14 deletions(-)
diff --git a/net/core/sock.c b/net/core/sock.c
index e16a5db853c6..70744dbb6c3f 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
--
2.8.0.rc3.226.g39d4020
^ permalink raw reply related [flat|nested] 13+ messages in thread
* Re: [PATCH net-next 0/6] net: make TCP preemptible
2016-04-28 5:25 [PATCH net-next 0/6] net: make TCP preemptible Eric Dumazet
` (5 preceding siblings ...)
2016-04-28 5:25 ` [PATCH net-next 6/6] net: do not block BH while processing socket backlog Eric Dumazet
@ 2016-04-28 17:23 ` Alexei Starovoitov
2016-04-28 17:41 ` Eric Dumazet
2016-04-28 21:18 ` Marcelo Ricardo Leitner
7 siblings, 1 reply; 13+ messages in thread
From: Alexei Starovoitov @ 2016-04-28 17:23 UTC (permalink / raw)
To: Eric Dumazet; +Cc: David S . Miller, netdev, Eric Dumazet
On Wed, Apr 27, 2016 at 10:25:46PM -0700, Eric Dumazet wrote:
> 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.
> 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.
this looks pretty awesome.
the change will make the backlog run in bh enabled, so that one
large flow reciever will not penalize the rest of the system, right?
but you're saying that prequeue is also expensive, but not touched
by this patchset? was it addressed by your eariler patch?
Or more work still tbd?
I'm just trying to understand more about tcp stack.
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH net-next 0/6] net: make TCP preemptible
2016-04-28 17:23 ` [PATCH net-next 0/6] net: make TCP preemptible Alexei Starovoitov
@ 2016-04-28 17:41 ` Eric Dumazet
2016-04-28 17:51 ` Alexei Starovoitov
0 siblings, 1 reply; 13+ messages in thread
From: Eric Dumazet @ 2016-04-28 17:41 UTC (permalink / raw)
To: Alexei Starovoitov; +Cc: Eric Dumazet, David S . Miller, netdev
On Thu, 2016-04-28 at 10:23 -0700, Alexei Starovoitov wrote:
> On Wed, Apr 27, 2016 at 10:25:46PM -0700, Eric Dumazet wrote:
> > 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.
> > 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.
>
> this looks pretty awesome.
Yes, I am pretty excited ;)
> the change will make the backlog run in bh enabled, so that one
> large flow reciever will not penalize the rest of the system, right?
Not only large flows, but flows with losses/reorders.
Typically many flows are in this case when a congestion collapse
happens.
> but you're saying that prequeue is also expensive, but not touched
> by this patchset? was it addressed by your eariler patch?
> Or more work still tbd?
prequeue is handled by "[2/6] tcp: do not block bh during prequeue
processing"
Note that I also sent a patch earlier (("tcp: give prequeue mode some
care")) to control max size of prequeue to 32 packets.
> I'm just trying to understand more about tcp stack.
>
Sure ;)
I also have a patch to add scheduling point in sendmsg() (ie : draining
the backlog if not empty) for each new skb added to the write queue.
Since each skb is about 64KB (with GSO/TSO), it means an application no
longer will hold the socket lock too long, even when doing a
write()/sendmsg() of say 8 MB at once ;)
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH net-next 0/6] net: make TCP preemptible
2016-04-28 17:41 ` Eric Dumazet
@ 2016-04-28 17:51 ` Alexei Starovoitov
2016-04-28 18:04 ` Eric Dumazet
0 siblings, 1 reply; 13+ messages in thread
From: Alexei Starovoitov @ 2016-04-28 17:51 UTC (permalink / raw)
To: Eric Dumazet; +Cc: Eric Dumazet, David S . Miller, netdev
On Thu, Apr 28, 2016 at 10:41:10AM -0700, Eric Dumazet wrote:
> On Thu, 2016-04-28 at 10:23 -0700, Alexei Starovoitov wrote:
> > On Wed, Apr 27, 2016 at 10:25:46PM -0700, Eric Dumazet wrote:
> > > 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.
> > > 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.
> >
> > this looks pretty awesome.
>
> Yes, I am pretty excited ;)
>
> > the change will make the backlog run in bh enabled, so that one
> > large flow reciever will not penalize the rest of the system, right?
>
> Not only large flows, but flows with losses/reorders.
> Typically many flows are in this case when a congestion collapse
> happens.
>
>
>
> > but you're saying that prequeue is also expensive, but not touched
> > by this patchset? was it addressed by your eariler patch?
> > Or more work still tbd?
>
> prequeue is handled by "[2/6] tcp: do not block bh during prequeue
> processing"
got it. It applies to both v4 and v6, right?
> Note that I also sent a patch earlier (("tcp: give prequeue mode some
> care")) to control max size of prequeue to 32 packets.
>
> > I'm just trying to understand more about tcp stack.
> >
> Sure ;)
>
> I also have a patch to add scheduling point in sendmsg() (ie : draining
> the backlog if not empty) for each new skb added to the write queue.
>
> Since each skb is about 64KB (with GSO/TSO), it means an application no
> longer will hold the socket lock too long, even when doing a
> write()/sendmsg() of say 8 MB at once ;)
that would be awesome. I think map/reduce type jobs typically
do large sendmsg, so it should help p99 latency.
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH net-next 0/6] net: make TCP preemptible
2016-04-28 17:51 ` Alexei Starovoitov
@ 2016-04-28 18:04 ` Eric Dumazet
0 siblings, 0 replies; 13+ messages in thread
From: Eric Dumazet @ 2016-04-28 18:04 UTC (permalink / raw)
To: Alexei Starovoitov; +Cc: Eric Dumazet, David S . Miller, netdev
On Thu, 2016-04-28 at 10:51 -0700, Alexei Starovoitov wrote:
> got it. It applies to both v4 and v6, right?
You mean IPv6 ?
Well, you know, I decided to skip IPv6 and go to IPv8 anyway ;)
Yes, these changes apply for both IPv4 and IPv6 in the meantime.
> that would be awesome. I think map/reduce type jobs typically
> do large sendmsg, so it should help p99 latency.
Note that it should even help to send faster, since the ACK packets or
TCP Small Queue handlers are blocked until the sendmsg() was complete.
ACK packets usually open the window for more sends.
Many applications are using a loop and multiple sendmsg( ) with ~64KB
chunks to work around these latency issues.
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH net-next 0/6] net: make TCP preemptible
2016-04-28 5:25 [PATCH net-next 0/6] net: make TCP preemptible Eric Dumazet
` (6 preceding siblings ...)
2016-04-28 17:23 ` [PATCH net-next 0/6] net: make TCP preemptible Alexei Starovoitov
@ 2016-04-28 21:18 ` Marcelo Ricardo Leitner
7 siblings, 0 replies; 13+ messages in thread
From: Marcelo Ricardo Leitner @ 2016-04-28 21:18 UTC (permalink / raw)
To: Eric Dumazet; +Cc: David S . Miller, netdev, Eric Dumazet
On Wed, Apr 27, 2016 at 10:25:46PM -0700, Eric Dumazet wrote:
> 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.
> 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.
And due to that, it may potentially lead to packet drops on NIC ring
buffers. Great, thanks Eric.
> It is time to make UDP/TCP stacks preemptible.
>
> Note that fast path still runs from BH handler.
>
> Eric Dumazet (6):
> tcp: do not assume TCP code is non preemptible
> tcp: do not block bh during prequeue processing
> dccp: do not assume DCCP code is non preemptible
> udp: prepare for non BH masking at backlog processing
> sctp: prepare for socket backlog behavior change
> net: do not block BH while processing socket backlog
>
> net/core/sock.c | 22 +++------
> net/dccp/input.c | 2 +-
> net/dccp/ipv4.c | 4 +-
> net/dccp/ipv6.c | 4 +-
> net/dccp/options.c | 2 +-
> net/ipv4/tcp.c | 6 +--
> net/ipv4/tcp_cdg.c | 20 ++++----
> net/ipv4/tcp_cubic.c | 20 ++++----
> net/ipv4/tcp_fastopen.c | 12 ++---
> net/ipv4/tcp_input.c | 126 +++++++++++++++++++----------------------------
> net/ipv4/tcp_ipv4.c | 14 ++++--
> net/ipv4/tcp_minisocks.c | 2 +-
> net/ipv4/tcp_output.c | 7 ++-
> net/ipv4/tcp_recovery.c | 4 +-
> net/ipv4/tcp_timer.c | 10 ++--
> net/ipv4/udp.c | 4 +-
> net/ipv6/tcp_ipv6.c | 12 ++---
> net/ipv6/udp.c | 4 +-
> net/sctp/inqueue.c | 2 +
> 19 files changed, 124 insertions(+), 153 deletions(-)
>
> --
> 2.8.0.rc3.226.g39d4020
>
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH net-next 1/6] tcp: do not assume TCP code is non preemptible
2016-04-28 5:25 ` [PATCH net-next 1/6] tcp: do not assume TCP code is non preemptible Eric Dumazet
@ 2016-04-29 1:08 ` Eric Dumazet
0 siblings, 0 replies; 13+ messages in thread
From: Eric Dumazet @ 2016-04-29 1:08 UTC (permalink / raw)
To: Eric Dumazet, David Miller; +Cc: netdev
On Wed, 2016-04-27 at 22:25 -0700, Eric Dumazet wrote:
> 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>
> ---
I'll send a V2 including following changes I missed :
I'll also include the sendmsg() latency breaker.
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 0509a685d90c..25d527922b18 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -2698,7 +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)
@@ -2822,7 +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);
^ permalink raw reply related [flat|nested] 13+ messages in thread
end of thread, other threads:[~2016-04-29 1:08 UTC | newest]
Thread overview: 13+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2016-04-28 5:25 [PATCH net-next 0/6] net: make TCP preemptible Eric Dumazet
2016-04-28 5:25 ` [PATCH net-next 1/6] tcp: do not assume TCP code is non preemptible Eric Dumazet
2016-04-29 1:08 ` Eric Dumazet
2016-04-28 5:25 ` [PATCH net-next 2/6] tcp: do not block bh during prequeue processing Eric Dumazet
2016-04-28 5:25 ` [PATCH net-next 3/6] dccp: do not assume DCCP code is non preemptible Eric Dumazet
2016-04-28 5:25 ` [PATCH net-next 4/6] udp: prepare for non BH masking at backlog processing Eric Dumazet
2016-04-28 5:25 ` [PATCH net-next 5/6] sctp: prepare for socket backlog behavior change Eric Dumazet
2016-04-28 5:25 ` [PATCH net-next 6/6] net: do not block BH while processing socket backlog Eric Dumazet
2016-04-28 17:23 ` [PATCH net-next 0/6] net: make TCP preemptible Alexei Starovoitov
2016-04-28 17:41 ` Eric Dumazet
2016-04-28 17:51 ` Alexei Starovoitov
2016-04-28 18:04 ` Eric Dumazet
2016-04-28 21:18 ` Marcelo Ricardo Leitner
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