summaryrefslogtreecommitdiff
path: root/net/ipv4/tcp_input.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2015-06-25 02:49:49 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2015-06-25 02:49:49 +0300
commite0456717e483bb8a9431b80a5bdc99a928b9b003 (patch)
tree5eb5add2bafd1f20326d70f5cb3b711d00a40b10 /net/ipv4/tcp_input.c
parent98ec21a01896751b673b6c731ca8881daa8b2c6d (diff)
parent1ea2d020ba477cb7011a7174e8501a9e04a325d4 (diff)
downloadlinux-e0456717e483bb8a9431b80a5bdc99a928b9b003.tar.xz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller: 1) Add TX fast path in mac80211, from Johannes Berg. 2) Add TSO/GRO support to ibmveth, from Thomas Falcon 3) Move away from cached routes in ipv6, just like ipv4, from Martin KaFai Lau. 4) Lots of new rhashtable tests, from Thomas Graf. 5) Run ingress qdisc lockless, from Alexei Starovoitov. 6) Allow servers to fetch TCP packet headers for SYN packets of new connections, for fingerprinting. From Eric Dumazet. 7) Add mode parameter to pktgen, for testing receive. From Alexei Starovoitov. 8) Cache access optimizations via simplifications of build_skb(), from Alexander Duyck. 9) Move page frag allocator under mm/, also from Alexander. 10) Add xmit_more support to hv_netvsc, from KY Srinivasan. 11) Add a counter guard in case we try to perform endless reclassify loops in the packet scheduler. 12) Extern flow dissector to be programmable and use it in new "Flower" classifier. From Jiri Pirko. 13) AF_PACKET fanout rollover fixes, performance improvements, and new statistics. From Willem de Bruijn. 14) Add netdev driver for GENEVE tunnels, from John W Linville. 15) Add ingress netfilter hooks and filtering, from Pablo Neira Ayuso. 16) Fix handling of epoll edge triggers in TCP, from Eric Dumazet. 17) Add an ECN retry fallback for the initial TCP handshake, from Daniel Borkmann. 18) Add tail call support to BPF, from Alexei Starovoitov. 19) Add several pktgen helper scripts, from Jesper Dangaard Brouer. 20) Add zerocopy support to AF_UNIX, from Hannes Frederic Sowa. 21) Favor even port numbers for allocation to connect() requests, and odd port numbers for bind(0), in an effort to help avoid ip_local_port_range exhaustion. From Eric Dumazet. 22) Add Cavium ThunderX driver, from Sunil Goutham. 23) Allow bpf programs to access skb_iif and dev->ifindex SKB metadata, from Alexei Starovoitov. 24) Add support for T6 chips in cxgb4vf driver, from Hariprasad Shenai. 25) Double TCP Small Queues default to 256K to accomodate situations like the XEN driver and wireless aggregation. From Wei Liu. 26) Add more entropy inputs to flow dissector, from Tom Herbert. 27) Add CDG congestion control algorithm to TCP, from Kenneth Klette Jonassen. 28) Convert ipset over to RCU locking, from Jozsef Kadlecsik. 29) Track and act upon link status of ipv4 route nexthops, from Andy Gospodarek. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1670 commits) bridge: vlan: flush the dynamically learned entries on port vlan delete bridge: multicast: add a comment to br_port_state_selection about blocking state net: inet_diag: export IPV6_V6ONLY sockopt stmmac: troubleshoot unexpected bits in des0 & des1 net: ipv4 sysctl option to ignore routes when nexthop link is down net: track link-status of ipv4 nexthops net: switchdev: ignore unsupported bridge flags net: Cavium: Fix MAC address setting in shutdown state drivers: net: xgene: fix for ACPI support without ACPI ip: report the original address of ICMP messages net/mlx5e: Prefetch skb data on RX net/mlx5e: Pop cq outside mlx5e_get_cqe net/mlx5e: Remove mlx5e_cq.sqrq back-pointer net/mlx5e: Remove extra spaces net/mlx5e: Avoid TX CQE generation if more xmit packets expected net/mlx5e: Avoid redundant dev_kfree_skb() upon NOP completion net/mlx5e: Remove re-assignment of wq type in mlx5e_enable_rq() net/mlx5e: Use skb_shinfo(skb)->gso_segs rather than counting them net/mlx5e: Static mapping of netdev priv resources to/from netdev TX queues net/mlx4_en: Use HW counters for rx/tx bytes/packets in PF device ...
Diffstat (limited to 'net/ipv4/tcp_input.c')
-rw-r--r--net/ipv4/tcp_input.c139
1 files changed, 78 insertions, 61 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index c9ab964189a0..684f095d196e 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -359,7 +359,7 @@ static void tcp_grow_window(struct sock *sk, const struct sk_buff *skb)
/* Check #1 */
if (tp->rcv_ssthresh < tp->window_clamp &&
(int)tp->rcv_ssthresh < tcp_space(sk) &&
- !sk_under_memory_pressure(sk)) {
+ !tcp_under_memory_pressure(sk)) {
int incr;
/* Check #2. Increase window, if skb with such overhead
@@ -446,7 +446,7 @@ static void tcp_clamp_window(struct sock *sk)
if (sk->sk_rcvbuf < sysctl_tcp_rmem[2] &&
!(sk->sk_userlocks & SOCK_RCVBUF_LOCK) &&
- !sk_under_memory_pressure(sk) &&
+ !tcp_under_memory_pressure(sk) &&
sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)) {
sk->sk_rcvbuf = min(atomic_read(&sk->sk_rmem_alloc),
sysctl_tcp_rmem[2]);
@@ -1130,7 +1130,12 @@ static bool tcp_check_dsack(struct sock *sk, const struct sk_buff *ack_skb,
struct tcp_sacktag_state {
int reord;
int fack_count;
- long rtt_us; /* RTT measured by SACKing never-retransmitted data */
+ /* Timestamps for earliest and latest never-retransmitted segment
+ * that was SACKed. RTO needs the earliest RTT to stay conservative,
+ * but congestion control should still get an accurate delay signal.
+ */
+ struct skb_mstamp first_sackt;
+ struct skb_mstamp last_sackt;
int flag;
};
@@ -1233,14 +1238,9 @@ static u8 tcp_sacktag_one(struct sock *sk,
state->reord);
if (!after(end_seq, tp->high_seq))
state->flag |= FLAG_ORIG_SACK_ACKED;
- /* Pick the earliest sequence sacked for RTT */
- if (state->rtt_us < 0) {
- struct skb_mstamp now;
-
- skb_mstamp_get(&now);
- state->rtt_us = skb_mstamp_us_delta(&now,
- xmit_time);
- }
+ if (state->first_sackt.v64 == 0)
+ state->first_sackt = *xmit_time;
+ state->last_sackt = *xmit_time;
}
if (sacked & TCPCB_LOST) {
@@ -1316,16 +1316,12 @@ static bool tcp_shifted_skb(struct sock *sk, struct sk_buff *skb,
* code can come after this skb later on it's better to keep
* setting gso_size to something.
*/
- if (!skb_shinfo(prev)->gso_size) {
- skb_shinfo(prev)->gso_size = mss;
- skb_shinfo(prev)->gso_type = sk->sk_gso_type;
- }
+ if (!TCP_SKB_CB(prev)->tcp_gso_size)
+ TCP_SKB_CB(prev)->tcp_gso_size = mss;
/* CHECKME: To clear or not to clear? Mimics normal skb currently */
- if (tcp_skb_pcount(skb) <= 1) {
- skb_shinfo(skb)->gso_size = 0;
- skb_shinfo(skb)->gso_type = 0;
- }
+ if (tcp_skb_pcount(skb) <= 1)
+ TCP_SKB_CB(skb)->tcp_gso_size = 0;
/* Difference in this won't matter, both ACKed by the same cumul. ACK */
TCP_SKB_CB(prev)->sacked |= (TCP_SKB_CB(skb)->sacked & TCPCB_EVER_RETRANS);
@@ -1634,7 +1630,7 @@ static int tcp_sack_cache_ok(const struct tcp_sock *tp, const struct tcp_sack_bl
static int
tcp_sacktag_write_queue(struct sock *sk, const struct sk_buff *ack_skb,
- u32 prior_snd_una, long *sack_rtt_us)
+ u32 prior_snd_una, struct tcp_sacktag_state *state)
{
struct tcp_sock *tp = tcp_sk(sk);
const unsigned char *ptr = (skb_transport_header(ack_skb) +
@@ -1642,7 +1638,6 @@ tcp_sacktag_write_queue(struct sock *sk, const struct sk_buff *ack_skb,
struct tcp_sack_block_wire *sp_wire = (struct tcp_sack_block_wire *)(ptr+2);
struct tcp_sack_block sp[TCP_NUM_SACKS];
struct tcp_sack_block *cache;
- struct tcp_sacktag_state state;
struct sk_buff *skb;
int num_sacks = min(TCP_NUM_SACKS, (ptr[1] - TCPOLEN_SACK_BASE) >> 3);
int used_sacks;
@@ -1650,9 +1645,8 @@ tcp_sacktag_write_queue(struct sock *sk, const struct sk_buff *ack_skb,
int i, j;
int first_sack_index;
- state.flag = 0;
- state.reord = tp->packets_out;
- state.rtt_us = -1L;
+ state->flag = 0;
+ state->reord = tp->packets_out;
if (!tp->sacked_out) {
if (WARN_ON(tp->fackets_out))
@@ -1663,7 +1657,7 @@ tcp_sacktag_write_queue(struct sock *sk, const struct sk_buff *ack_skb,
found_dup_sack = tcp_check_dsack(sk, ack_skb, sp_wire,
num_sacks, prior_snd_una);
if (found_dup_sack)
- state.flag |= FLAG_DSACKING_ACK;
+ state->flag |= FLAG_DSACKING_ACK;
/* Eliminate too old ACKs, but take into
* account more or less fresh ones, they can
@@ -1728,7 +1722,7 @@ tcp_sacktag_write_queue(struct sock *sk, const struct sk_buff *ack_skb,
}
skb = tcp_write_queue_head(sk);
- state.fack_count = 0;
+ state->fack_count = 0;
i = 0;
if (!tp->sacked_out) {
@@ -1762,10 +1756,10 @@ tcp_sacktag_write_queue(struct sock *sk, const struct sk_buff *ack_skb,
/* Head todo? */
if (before(start_seq, cache->start_seq)) {
- skb = tcp_sacktag_skip(skb, sk, &state,
+ skb = tcp_sacktag_skip(skb, sk, state,
start_seq);
skb = tcp_sacktag_walk(skb, sk, next_dup,
- &state,
+ state,
start_seq,
cache->start_seq,
dup_sack);
@@ -1776,7 +1770,7 @@ tcp_sacktag_write_queue(struct sock *sk, const struct sk_buff *ack_skb,
goto advance_sp;
skb = tcp_maybe_skipping_dsack(skb, sk, next_dup,
- &state,
+ state,
cache->end_seq);
/* ...tail remains todo... */
@@ -1785,12 +1779,12 @@ tcp_sacktag_write_queue(struct sock *sk, const struct sk_buff *ack_skb,
skb = tcp_highest_sack(sk);
if (!skb)
break;
- state.fack_count = tp->fackets_out;
+ state->fack_count = tp->fackets_out;
cache++;
goto walk;
}
- skb = tcp_sacktag_skip(skb, sk, &state, cache->end_seq);
+ skb = tcp_sacktag_skip(skb, sk, state, cache->end_seq);
/* Check overlap against next cached too (past this one already) */
cache++;
continue;
@@ -1800,12 +1794,12 @@ tcp_sacktag_write_queue(struct sock *sk, const struct sk_buff *ack_skb,
skb = tcp_highest_sack(sk);
if (!skb)
break;
- state.fack_count = tp->fackets_out;
+ state->fack_count = tp->fackets_out;
}
- skb = tcp_sacktag_skip(skb, sk, &state, start_seq);
+ skb = tcp_sacktag_skip(skb, sk, state, start_seq);
walk:
- skb = tcp_sacktag_walk(skb, sk, next_dup, &state,
+ skb = tcp_sacktag_walk(skb, sk, next_dup, state,
start_seq, end_seq, dup_sack);
advance_sp:
@@ -1820,9 +1814,9 @@ advance_sp:
for (j = 0; j < used_sacks; j++)
tp->recv_sack_cache[i++] = sp[j];
- if ((state.reord < tp->fackets_out) &&
+ if ((state->reord < tp->fackets_out) &&
((inet_csk(sk)->icsk_ca_state != TCP_CA_Loss) || tp->undo_marker))
- tcp_update_reordering(sk, tp->fackets_out - state.reord, 0);
+ tcp_update_reordering(sk, tp->fackets_out - state->reord, 0);
tcp_mark_lost_retrans(sk);
tcp_verify_left_out(tp);
@@ -1834,8 +1828,7 @@ out:
WARN_ON((int)tp->retrans_out < 0);
WARN_ON((int)tcp_packets_in_flight(tp) < 0);
#endif
- *sack_rtt_us = state.rtt_us;
- return state.flag;
+ return state->flag;
}
/* Limits sacked_out so that sum with lost_out isn't ever larger than
@@ -2255,7 +2248,7 @@ static void tcp_mark_head_lost(struct sock *sk, int packets, int mark_head)
(oldcnt >= packets))
break;
- mss = skb_shinfo(skb)->gso_size;
+ mss = tcp_skb_mss(skb);
err = tcp_fragment(sk, skb, (packets - oldcnt) * mss,
mss, GFP_ATOMIC);
if (err < 0)
@@ -2555,6 +2548,7 @@ void tcp_enter_cwr(struct sock *sk)
tcp_set_ca_state(sk, TCP_CA_CWR);
}
}
+EXPORT_SYMBOL(tcp_enter_cwr);
static void tcp_try_keep_open(struct sock *sk)
{
@@ -3055,7 +3049,8 @@ static void tcp_ack_tstamp(struct sock *sk, struct sk_buff *skb,
* arrived at the other end.
*/
static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets,
- u32 prior_snd_una, long sack_rtt_us)
+ u32 prior_snd_una,
+ struct tcp_sacktag_state *sack)
{
const struct inet_connection_sock *icsk = inet_csk(sk);
struct skb_mstamp first_ackt, last_ackt, now;
@@ -3063,8 +3058,9 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets,
u32 prior_sacked = tp->sacked_out;
u32 reord = tp->packets_out;
bool fully_acked = true;
- long ca_seq_rtt_us = -1L;
+ long sack_rtt_us = -1L;
long seq_rtt_us = -1L;
+ long ca_rtt_us = -1L;
struct sk_buff *skb;
u32 pkts_acked = 0;
bool rtt_update;
@@ -3153,15 +3149,16 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets,
skb_mstamp_get(&now);
if (likely(first_ackt.v64)) {
seq_rtt_us = skb_mstamp_us_delta(&now, &first_ackt);
- ca_seq_rtt_us = skb_mstamp_us_delta(&now, &last_ackt);
+ ca_rtt_us = skb_mstamp_us_delta(&now, &last_ackt);
+ }
+ if (sack->first_sackt.v64) {
+ sack_rtt_us = skb_mstamp_us_delta(&now, &sack->first_sackt);
+ ca_rtt_us = skb_mstamp_us_delta(&now, &sack->last_sackt);
}
rtt_update = tcp_ack_update_rtt(sk, flag, seq_rtt_us, sack_rtt_us);
if (flag & FLAG_ACKED) {
- const struct tcp_congestion_ops *ca_ops
- = inet_csk(sk)->icsk_ca_ops;
-
tcp_rearm_rto(sk);
if (unlikely(icsk->icsk_mtup.probe_size &&
!after(tp->mtu_probe.probe_seq_end, tp->snd_una))) {
@@ -3184,11 +3181,6 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets,
tp->fackets_out -= min(pkts_acked, tp->fackets_out);
- if (ca_ops->pkts_acked) {
- long rtt_us = min_t(ulong, ca_seq_rtt_us, sack_rtt_us);
- ca_ops->pkts_acked(sk, pkts_acked, rtt_us);
- }
-
} else if (skb && rtt_update && sack_rtt_us >= 0 &&
sack_rtt_us > skb_mstamp_us_delta(&now, &skb->skb_mstamp)) {
/* Do not re-arm RTO if the sack RTT is measured from data sent
@@ -3198,6 +3190,9 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets,
tcp_rearm_rto(sk);
}
+ if (icsk->icsk_ca_ops->pkts_acked)
+ icsk->icsk_ca_ops->pkts_acked(sk, pkts_acked, ca_rtt_us);
+
#if FASTRETRANS_DEBUG > 0
WARN_ON((int)tp->sacked_out < 0);
WARN_ON((int)tp->lost_out < 0);
@@ -3238,7 +3233,7 @@ static void tcp_ack_probe(struct sock *sk)
* This function is not for random using!
*/
} else {
- unsigned long when = inet_csk_rto_backoff(icsk, TCP_RTO_MAX);
+ unsigned long when = tcp_probe0_when(sk, TCP_RTO_MAX);
inet_csk_reset_xmit_timer(sk, ICSK_TIME_PROBE0,
when, TCP_RTO_MAX);
@@ -3466,6 +3461,7 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
{
struct inet_connection_sock *icsk = inet_csk(sk);
struct tcp_sock *tp = tcp_sk(sk);
+ struct tcp_sacktag_state sack_state;
u32 prior_snd_una = tp->snd_una;
u32 ack_seq = TCP_SKB_CB(skb)->seq;
u32 ack = TCP_SKB_CB(skb)->ack_seq;
@@ -3474,7 +3470,8 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
int prior_packets = tp->packets_out;
const int prior_unsacked = tp->packets_out - tp->sacked_out;
int acked = 0; /* Number of packets newly acked */
- long sack_rtt_us = -1L;
+
+ sack_state.first_sackt.v64 = 0;
/* We very likely will need to access write queue head. */
prefetchw(sk->sk_write_queue.next);
@@ -3538,7 +3535,7 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
if (TCP_SKB_CB(skb)->sacked)
flag |= tcp_sacktag_write_queue(sk, skb, prior_snd_una,
- &sack_rtt_us);
+ &sack_state);
if (tcp_ecn_rcv_ecn_echo(tp, tcp_hdr(skb))) {
flag |= FLAG_ECE;
@@ -3563,7 +3560,7 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
/* See if we can take anything off of the retransmit queue. */
acked = tp->packets_out;
flag |= tcp_clean_rtx_queue(sk, prior_fackets, prior_snd_una,
- sack_rtt_us);
+ &sack_state);
acked -= tp->packets_out;
/* Advance cwnd if state allows */
@@ -3615,7 +3612,7 @@ old_ack:
*/
if (TCP_SKB_CB(skb)->sacked) {
flag |= tcp_sacktag_write_queue(sk, skb, prior_snd_una,
- &sack_rtt_us);
+ &sack_state);
tcp_fastretrans_alert(sk, acked, prior_unsacked,
is_dupack, flag);
}
@@ -4514,10 +4511,12 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb)
if (eaten <= 0) {
queue_and_out:
- if (eaten < 0 &&
- tcp_try_rmem_schedule(sk, skb, skb->truesize))
- goto drop;
-
+ if (eaten < 0) {
+ if (skb_queue_len(&sk->sk_receive_queue) == 0)
+ sk_forced_mem_schedule(sk, skb->truesize);
+ else if (tcp_try_rmem_schedule(sk, skb, skb->truesize))
+ goto drop;
+ }
eaten = tcp_queue_rcv(sk, skb, 0, &fragstolen);
}
tcp_rcv_nxt_update(tp, TCP_SKB_CB(skb)->end_seq);
@@ -4788,7 +4787,7 @@ static int tcp_prune_queue(struct sock *sk)
if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
tcp_clamp_window(sk);
- else if (sk_under_memory_pressure(sk))
+ else if (tcp_under_memory_pressure(sk))
tp->rcv_ssthresh = min(tp->rcv_ssthresh, 4U * tp->advmss);
tcp_collapse_ofo_queue(sk);
@@ -4832,7 +4831,7 @@ static bool tcp_should_expand_sndbuf(const struct sock *sk)
return false;
/* If we are under global TCP memory pressure, do not expand. */
- if (sk_under_memory_pressure(sk))
+ if (tcp_under_memory_pressure(sk))
return false;
/* If we are under soft global TCP memory pressure, do not expand. */
@@ -6067,6 +6066,23 @@ static bool tcp_syn_flood_action(struct sock *sk,
return want_cookie;
}
+static void tcp_reqsk_record_syn(const struct sock *sk,
+ struct request_sock *req,
+ const struct sk_buff *skb)
+{
+ if (tcp_sk(sk)->save_syn) {
+ u32 len = skb_network_header_len(skb) + tcp_hdrlen(skb);
+ u32 *copy;
+
+ copy = kmalloc(len + sizeof(u32), GFP_ATOMIC);
+ if (copy) {
+ copy[0] = len;
+ memcpy(&copy[1], skb_network_header(skb), len);
+ req->saved_syn = copy;
+ }
+ }
+}
+
int tcp_conn_request(struct request_sock_ops *rsk_ops,
const struct tcp_request_sock_ops *af_ops,
struct sock *sk, struct sk_buff *skb)
@@ -6199,6 +6215,7 @@ int tcp_conn_request(struct request_sock_ops *rsk_ops,
tcp_rsk(req)->tfo_listener = false;
af_ops->queue_hash_add(sk, req, TCP_TIMEOUT_INIT);
}
+ tcp_reqsk_record_syn(sk, req, skb);
return 0;