From 05b055e89121394058c75dc354e9a46e1e765579 Mon Sep 17 00:00:00 2001 From: Francis Yan Date: Sun, 27 Nov 2016 23:07:13 -0800 Subject: [PATCH 1/6] tcp: instrument tcp sender limits chronographs This patch implements the skeleton of the TCP chronograph instrumentation on sender side limits: 1) idle (unspec) 2) busy sending data other than 3-4 below 3) rwnd-limited 4) sndbuf-limited The limits are enumerated 'tcp_chrono'. Since a connection in theory can idle forever, we do not track the actual length of this uninteresting idle period. For the rest we track how long the sender spends in each limit. At any point during the life time of a connection, the sender must be in one of the four states. If there are multiple conditions worthy of tracking in a chronograph then the highest priority enum takes precedence over the other conditions. So that if something "more interesting" starts happening, stop the previous chrono and start a new one. The time unit is jiffy(u32) in order to save space in tcp_sock. This implies application must sample the stats no longer than every 49 days of 1ms jiffy. Signed-off-by: Francis Yan Signed-off-by: Yuchung Cheng Signed-off-by: Soheil Hassas Yeganeh Acked-by: Neal Cardwell Signed-off-by: David S. Miller --- include/linux/tcp.h | 7 +++++-- include/net/tcp.h | 14 ++++++++++++++ net/ipv4/tcp_output.c | 30 ++++++++++++++++++++++++++++++ 3 files changed, 49 insertions(+), 2 deletions(-) diff --git a/include/linux/tcp.h b/include/linux/tcp.h index 32a7c7e35b715..d5d3bd8143387 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -211,8 +211,11 @@ struct tcp_sock { u8 reord; /* reordering detected */ } rack; u16 advmss; /* Advertised MSS */ - u8 rate_app_limited:1, /* rate_{delivered,interval_us} limited? */ - unused:7; + u32 chrono_start; /* Start time in jiffies of a TCP chrono */ + u32 chrono_stat[3]; /* Time in jiffies for chrono_stat stats */ + u8 chrono_type:2, /* current chronograph type */ + rate_app_limited:1, /* rate_{delivered,interval_us} limited? */ + unused:5; u8 nonagle : 4,/* Disable Nagle algorithm? */ thin_lto : 1,/* Use linear timeouts for thin streams */ thin_dupack : 1,/* Fast retransmit on first dupack */ diff --git a/include/net/tcp.h b/include/net/tcp.h index 7de80739adaba..e5ff4083870d2 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1516,6 +1516,20 @@ struct tcp_fastopen_context { struct rcu_head rcu; }; +/* Latencies incurred by various limits for a sender. They are + * chronograph-like stats that are mutually exclusive. + */ +enum tcp_chrono { + TCP_CHRONO_UNSPEC, + TCP_CHRONO_BUSY, /* Actively sending data (non-empty write queue) */ + TCP_CHRONO_RWND_LIMITED, /* Stalled by insufficient receive window */ + TCP_CHRONO_SNDBUF_LIMITED, /* Stalled by insufficient send buffer */ + __TCP_CHRONO_MAX, +}; + +void tcp_chrono_start(struct sock *sk, const enum tcp_chrono type); +void tcp_chrono_stop(struct sock *sk, const enum tcp_chrono type); + /* write queue abstraction */ static inline void tcp_write_queue_purge(struct sock *sk) { diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 19105b46a3043..34f751776a013 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -2081,6 +2081,36 @@ static bool tcp_small_queue_check(struct sock *sk, const struct sk_buff *skb, return false; } +static void tcp_chrono_set(struct tcp_sock *tp, const enum tcp_chrono new) +{ + const u32 now = tcp_time_stamp; + + if (tp->chrono_type > TCP_CHRONO_UNSPEC) + tp->chrono_stat[tp->chrono_type - 1] += now - tp->chrono_start; + tp->chrono_start = now; + tp->chrono_type = new; +} + +void tcp_chrono_start(struct sock *sk, const enum tcp_chrono type) +{ + struct tcp_sock *tp = tcp_sk(sk); + + /* If there are multiple conditions worthy of tracking in a + * chronograph then the highest priority enum takes precedence over + * the other conditions. So that if something "more interesting" + * starts happening, stop the previous chrono and start a new one. + */ + if (type > tp->chrono_type) + tcp_chrono_set(tp, type); +} + +void tcp_chrono_stop(struct sock *sk, const enum tcp_chrono type) +{ + struct tcp_sock *tp = tcp_sk(sk); + + tcp_chrono_set(tp, TCP_CHRONO_UNSPEC); +} + /* This routine writes packets to the network. It advances the * send_head. This happens as incoming acks open up the remote * window for us. From 0f87230d1a6c253681550c6064715d06a32be73d Mon Sep 17 00:00:00 2001 From: Francis Yan Date: Sun, 27 Nov 2016 23:07:14 -0800 Subject: [PATCH 2/6] tcp: instrument how long TCP is busy sending This patch measures TCP busy time, which is defined as the period of time when sender has data (or FIN) to send. The time starts when data is buffered and stops when the write queue is flushed by ACKs or error events. Note the busy time does not include SYN time, unless data is included in SYN (i.e. Fast Open). It does include FIN time even if the FIN carries no payload. Excluding pure FIN is possible but would incur one additional test in the fast path, which may not be worth it. Signed-off-by: Francis Yan Signed-off-by: Yuchung Cheng Signed-off-by: Soheil Hassas Yeganeh Acked-by: Neal Cardwell Signed-off-by: David S. Miller --- include/net/tcp.h | 6 +++++- net/ipv4/tcp_input.c | 3 +++ net/ipv4/tcp_output.c | 19 ++++++++++++++++--- 3 files changed, 24 insertions(+), 4 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index e5ff4083870d2..3e097e39d4d26 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1535,6 +1535,7 @@ static inline void tcp_write_queue_purge(struct sock *sk) { struct sk_buff *skb; + tcp_chrono_stop(sk, TCP_CHRONO_BUSY); while ((skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) sk_wmem_free_skb(sk, skb); sk_mem_reclaim(sk); @@ -1593,8 +1594,10 @@ static inline void tcp_advance_send_head(struct sock *sk, const struct sk_buff * static inline void tcp_check_send_head(struct sock *sk, struct sk_buff *skb_unlinked) { - if (sk->sk_send_head == skb_unlinked) + if (sk->sk_send_head == skb_unlinked) { sk->sk_send_head = NULL; + tcp_chrono_stop(sk, TCP_CHRONO_BUSY); + } if (tcp_sk(sk)->highest_sack == skb_unlinked) tcp_sk(sk)->highest_sack = NULL; } @@ -1616,6 +1619,7 @@ static inline void tcp_add_write_queue_tail(struct sock *sk, struct sk_buff *skb /* Queue it, remembering where we must start sending. */ if (sk->sk_send_head == NULL) { sk->sk_send_head = skb; + tcp_chrono_start(sk, TCP_CHRONO_BUSY); if (tcp_sk(sk)->highest_sack == NULL) tcp_sk(sk)->highest_sack = skb; diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 22e6a2097ff60..a5d1727616100 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3178,6 +3178,9 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets, tp->lost_skb_hint = NULL; } + if (!skb) + tcp_chrono_stop(sk, TCP_CHRONO_BUSY); + if (likely(between(tp->snd_up, prior_snd_una, tp->snd_una))) tp->snd_up = tp->snd_una; diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 34f751776a013..e8ea584106e0b 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -2096,8 +2096,8 @@ void tcp_chrono_start(struct sock *sk, const enum tcp_chrono type) struct tcp_sock *tp = tcp_sk(sk); /* If there are multiple conditions worthy of tracking in a - * chronograph then the highest priority enum takes precedence over - * the other conditions. So that if something "more interesting" + * chronograph then the highest priority enum takes precedence + * over the other conditions. So that if something "more interesting" * starts happening, stop the previous chrono and start a new one. */ if (type > tp->chrono_type) @@ -2108,7 +2108,18 @@ void tcp_chrono_stop(struct sock *sk, const enum tcp_chrono type) { struct tcp_sock *tp = tcp_sk(sk); - tcp_chrono_set(tp, TCP_CHRONO_UNSPEC); + + /* There are multiple conditions worthy of tracking in a + * chronograph, so that the highest priority enum takes + * precedence over the other conditions (see tcp_chrono_start). + * If a condition stops, we only stop chrono tracking if + * it's the "most interesting" or current chrono we are + * tracking and starts busy chrono if we have pending data. + */ + if (tcp_write_queue_empty(sk)) + tcp_chrono_set(tp, TCP_CHRONO_UNSPEC); + else if (type == tp->chrono_type) + tcp_chrono_set(tp, TCP_CHRONO_BUSY); } /* This routine writes packets to the network. It advances the @@ -3328,6 +3339,8 @@ static int tcp_send_syn_data(struct sock *sk, struct sk_buff *syn) fo->copied = space; tcp_connect_queue_skb(sk, syn_data); + if (syn_data->len) + tcp_chrono_start(sk, TCP_CHRONO_BUSY); err = tcp_transmit_skb(sk, syn_data, 1, sk->sk_allocation); From 5615f88614a47d2b802e1d14d31b623696109276 Mon Sep 17 00:00:00 2001 From: Francis Yan Date: Sun, 27 Nov 2016 23:07:15 -0800 Subject: [PATCH 3/6] tcp: instrument how long TCP is limited by receive window This patch measures the total time when the TCP stops sending because the receiver's advertised window is not large enough. Note that once the limit is lifted we are likely in the busy status if we have data pending. Signed-off-by: Francis Yan Signed-off-by: Yuchung Cheng Signed-off-by: Soheil Hassas Yeganeh Acked-by: Neal Cardwell Signed-off-by: David S. Miller --- net/ipv4/tcp_output.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index e8ea584106e0b..b74444cee24d3 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -2144,7 +2144,7 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle, unsigned int tso_segs, sent_pkts; int cwnd_quota; int result; - bool is_cwnd_limited = false; + bool is_cwnd_limited = false, is_rwnd_limited = false; u32 max_segs; sent_pkts = 0; @@ -2181,8 +2181,10 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle, break; } - if (unlikely(!tcp_snd_wnd_test(tp, skb, mss_now))) + if (unlikely(!tcp_snd_wnd_test(tp, skb, mss_now))) { + is_rwnd_limited = true; break; + } if (tso_segs == 1) { if (unlikely(!tcp_nagle_test(tp, skb, mss_now, @@ -2227,6 +2229,11 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle, break; } + if (is_rwnd_limited) + tcp_chrono_start(sk, TCP_CHRONO_RWND_LIMITED); + else + tcp_chrono_stop(sk, TCP_CHRONO_RWND_LIMITED); + if (likely(sent_pkts)) { if (tcp_in_cwnd_reduction(sk)) tp->prr_out += sent_pkts; From b0f71bd3e190df827d25d7f19bf09037567f14b7 Mon Sep 17 00:00:00 2001 From: Francis Yan Date: Sun, 27 Nov 2016 23:07:16 -0800 Subject: [PATCH 4/6] tcp: instrument how long TCP is limited by insufficient send buffer This patch measures the amount of time when TCP runs out of new data to send to the network due to insufficient send buffer, while TCP is still busy delivering (i.e. write queue is not empty). The goal is to indicate either the send buffer autotuning or user SO_SNDBUF setting has resulted network under-utilization. The measurement starts conservatively by checking various conditions to minimize false claims (i.e. under-estimation is more likely). The measurement stops when the SOCK_NOSPACE flag is cleared. But it does not account the time elapsed till the next application write. Also the measurement only starts if the sender is still busy sending data, s.t. the limit accounted is part of the total busy time. Signed-off-by: Francis Yan Signed-off-by: Yuchung Cheng Signed-off-by: Soheil Hassas Yeganeh Acked-by: Neal Cardwell Signed-off-by: David S. Miller --- net/ipv4/tcp.c | 10 ++++++++-- net/ipv4/tcp_input.c | 5 ++++- net/ipv4/tcp_output.c | 12 ++++++++++++ 3 files changed, 24 insertions(+), 3 deletions(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 913f9bbfc030b..259ffb50e429b 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -996,8 +996,11 @@ static ssize_t do_tcp_sendpages(struct sock *sk, struct page *page, int offset, goto out; out_err: /* make sure we wake any epoll edge trigger waiter */ - if (unlikely(skb_queue_len(&sk->sk_write_queue) == 0 && err == -EAGAIN)) + if (unlikely(skb_queue_len(&sk->sk_write_queue) == 0 && + err == -EAGAIN)) { sk->sk_write_space(sk); + tcp_chrono_stop(sk, TCP_CHRONO_SNDBUF_LIMITED); + } return sk_stream_error(sk, flags, err); } @@ -1331,8 +1334,11 @@ int tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) out_err: err = sk_stream_error(sk, flags, err); /* make sure we wake any epoll edge trigger waiter */ - if (unlikely(skb_queue_len(&sk->sk_write_queue) == 0 && err == -EAGAIN)) + if (unlikely(skb_queue_len(&sk->sk_write_queue) == 0 && + err == -EAGAIN)) { sk->sk_write_space(sk); + tcp_chrono_stop(sk, TCP_CHRONO_SNDBUF_LIMITED); + } release_sock(sk); return err; } diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index a5d1727616100..56fe736fd64db 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -5059,8 +5059,11 @@ static void tcp_check_space(struct sock *sk) /* pairs with tcp_poll() */ smp_mb__after_atomic(); if (sk->sk_socket && - test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) + test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) { tcp_new_space(sk); + if (!test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) + tcp_chrono_stop(sk, TCP_CHRONO_SNDBUF_LIMITED); + } } } diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index b74444cee24d3..d3545d0cff756 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -1514,6 +1514,18 @@ static void tcp_cwnd_validate(struct sock *sk, bool is_cwnd_limited) if (sysctl_tcp_slow_start_after_idle && (s32)(tcp_time_stamp - tp->snd_cwnd_stamp) >= inet_csk(sk)->icsk_rto) tcp_cwnd_application_limited(sk); + + /* The following conditions together indicate the starvation + * is caused by insufficient sender buffer: + * 1) just sent some data (see tcp_write_xmit) + * 2) not cwnd limited (this else condition) + * 3) no more data to send (null tcp_send_head ) + * 4) application is hitting buffer limit (SOCK_NOSPACE) + */ + if (!tcp_send_head(sk) && sk->sk_socket && + test_bit(SOCK_NOSPACE, &sk->sk_socket->flags) && + (1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) + tcp_chrono_start(sk, TCP_CHRONO_SNDBUF_LIMITED); } } From efd90174167530c67a54273fd5d8369c87f9bd32 Mon Sep 17 00:00:00 2001 From: Francis Yan Date: Sun, 27 Nov 2016 23:07:17 -0800 Subject: [PATCH 5/6] tcp: export sender limits chronographs to TCP_INFO This patch exports all the sender chronograph measurements collected in the previous patches to TCP_INFO interface. Note that busy time exported includes all the other sending limits (rwnd-limited, sndbuf-limited). Internally the time unit is jiffy but externally the measurements are in microseconds for future extensions. Signed-off-by: Francis Yan Signed-off-by: Yuchung Cheng Signed-off-by: Soheil Hassas Yeganeh Acked-by: Neal Cardwell Signed-off-by: David S. Miller --- include/uapi/linux/tcp.h | 4 ++++ net/ipv4/tcp.c | 20 ++++++++++++++++++++ 2 files changed, 24 insertions(+) diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h index 73ac0db487f87..2863b661d6e1c 100644 --- a/include/uapi/linux/tcp.h +++ b/include/uapi/linux/tcp.h @@ -214,6 +214,10 @@ struct tcp_info { __u32 tcpi_data_segs_out; /* RFC4898 tcpEStatsDataSegsOut */ __u64 tcpi_delivery_rate; + + __u64 tcpi_busy_time; /* Time (usec) busy sending data */ + __u64 tcpi_rwnd_limited; /* Time (usec) limited by receive window */ + __u64 tcpi_sndbuf_limited; /* Time (usec) limited by send buffer */ }; /* for TCP_MD5SIG socket option */ diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 259ffb50e429b..cdde20f49999c 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2708,6 +2708,25 @@ int compat_tcp_setsockopt(struct sock *sk, int level, int optname, EXPORT_SYMBOL(compat_tcp_setsockopt); #endif +static void tcp_get_info_chrono_stats(const struct tcp_sock *tp, + struct tcp_info *info) +{ + u64 stats[__TCP_CHRONO_MAX], total = 0; + enum tcp_chrono i; + + for (i = TCP_CHRONO_BUSY; i < __TCP_CHRONO_MAX; ++i) { + stats[i] = tp->chrono_stat[i - 1]; + if (i == tp->chrono_type) + stats[i] += tcp_time_stamp - tp->chrono_start; + stats[i] *= USEC_PER_SEC / HZ; + total += stats[i]; + } + + info->tcpi_busy_time = total; + info->tcpi_rwnd_limited = stats[TCP_CHRONO_RWND_LIMITED]; + info->tcpi_sndbuf_limited = stats[TCP_CHRONO_SNDBUF_LIMITED]; +} + /* Return information about state of tcp endpoint in API format. */ void tcp_get_info(struct sock *sk, struct tcp_info *info) { @@ -2800,6 +2819,7 @@ void tcp_get_info(struct sock *sk, struct tcp_info *info) info->tcpi_bytes_acked = tp->bytes_acked; info->tcpi_bytes_received = tp->bytes_received; info->tcpi_notsent_bytes = max_t(int, 0, tp->write_seq - tp->snd_nxt); + tcp_get_info_chrono_stats(tp, info); unlock_sock_fast(sk, slow); From 1c885808e45601b2b6f68b30ac1d999e10b6f606 Mon Sep 17 00:00:00 2001 From: Francis Yan Date: Sun, 27 Nov 2016 23:07:18 -0800 Subject: [PATCH 6/6] tcp: SOF_TIMESTAMPING_OPT_STATS option for SO_TIMESTAMPING This patch exports the sender chronograph stats via the socket SO_TIMESTAMPING channel. Currently we can instrument how long a particular application unit of data was queued in TCP by tracking SOF_TIMESTAMPING_TX_SOFTWARE and SOF_TIMESTAMPING_TX_SCHED. Having these sender chronograph stats exported simultaneously along with these timestamps allow further breaking down the various sender limitation. For example, a video server can tell if a particular chunk of video on a connection takes a long time to deliver because TCP was experiencing small receive window. It is not possible to tell before this patch without packet traces. To prepare these stats, the user needs to set SOF_TIMESTAMPING_OPT_STATS and SOF_TIMESTAMPING_OPT_TSONLY flags while requesting other SOF_TIMESTAMPING TX timestamps. When the timestamps are available in the error queue, the stats are returned in a separate control message of type SCM_TIMESTAMPING_OPT_STATS, in a list of TLVs (struct nlattr) of types: TCP_NLA_BUSY_TIME, TCP_NLA_RWND_LIMITED, TCP_NLA_SNDBUF_LIMITED. Unit is microsecond. Signed-off-by: Francis Yan Signed-off-by: Yuchung Cheng Signed-off-by: Soheil Hassas Yeganeh Acked-by: Neal Cardwell Signed-off-by: David S. Miller --- Documentation/networking/timestamping.txt | 10 ++++++++++ arch/alpha/include/uapi/asm/socket.h | 2 ++ arch/frv/include/uapi/asm/socket.h | 2 ++ arch/ia64/include/uapi/asm/socket.h | 2 ++ arch/m32r/include/uapi/asm/socket.h | 2 ++ arch/mips/include/uapi/asm/socket.h | 2 ++ arch/mn10300/include/uapi/asm/socket.h | 2 ++ arch/parisc/include/uapi/asm/socket.h | 2 ++ arch/powerpc/include/uapi/asm/socket.h | 2 ++ arch/s390/include/uapi/asm/socket.h | 2 ++ arch/sparc/include/uapi/asm/socket.h | 2 ++ arch/xtensa/include/uapi/asm/socket.h | 2 ++ include/linux/tcp.h | 2 ++ include/uapi/asm-generic/socket.h | 2 ++ include/uapi/linux/net_tstamp.h | 3 ++- include/uapi/linux/tcp.h | 8 ++++++++ net/core/skbuff.c | 14 +++++++++++--- net/core/sock.c | 7 +++++++ net/ipv4/tcp.c | 20 ++++++++++++++++++++ net/socket.c | 7 ++++++- 20 files changed, 90 insertions(+), 5 deletions(-) diff --git a/Documentation/networking/timestamping.txt b/Documentation/networking/timestamping.txt index 671cccf0dcd26..96f50694a7483 100644 --- a/Documentation/networking/timestamping.txt +++ b/Documentation/networking/timestamping.txt @@ -182,6 +182,16 @@ SOF_TIMESTAMPING_OPT_TSONLY: the timestamp even if sysctl net.core.tstamp_allow_data is 0. This option disables SOF_TIMESTAMPING_OPT_CMSG. +SOF_TIMESTAMPING_OPT_STATS: + + Optional stats that are obtained along with the transmit timestamps. + It must be used together with SOF_TIMESTAMPING_OPT_TSONLY. When the + transmit timestamp is available, the stats are available in a + separate control message of type SCM_TIMESTAMPING_OPT_STATS, as a + list of TLVs (struct nlattr) of types. These stats allow the + application to associate various transport layer stats with + the transmit timestamps, such as how long a certain block of + data was limited by peer's receiver window. New applications are encouraged to pass SOF_TIMESTAMPING_OPT_ID to disambiguate timestamps and SOF_TIMESTAMPING_OPT_TSONLY to operate diff --git a/arch/alpha/include/uapi/asm/socket.h b/arch/alpha/include/uapi/asm/socket.h index 9e46d6e656d97..afc901b7a6f6e 100644 --- a/arch/alpha/include/uapi/asm/socket.h +++ b/arch/alpha/include/uapi/asm/socket.h @@ -97,4 +97,6 @@ #define SO_CNX_ADVICE 53 +#define SCM_TIMESTAMPING_OPT_STATS 54 + #endif /* _UAPI_ASM_SOCKET_H */ diff --git a/arch/frv/include/uapi/asm/socket.h b/arch/frv/include/uapi/asm/socket.h index afbc98f02d278..81e03530ed39e 100644 --- a/arch/frv/include/uapi/asm/socket.h +++ b/arch/frv/include/uapi/asm/socket.h @@ -90,5 +90,7 @@ #define SO_CNX_ADVICE 53 +#define SCM_TIMESTAMPING_OPT_STATS 54 + #endif /* _ASM_SOCKET_H */ diff --git a/arch/ia64/include/uapi/asm/socket.h b/arch/ia64/include/uapi/asm/socket.h index 0018fad9039f4..57feb0c1f7d70 100644 --- a/arch/ia64/include/uapi/asm/socket.h +++ b/arch/ia64/include/uapi/asm/socket.h @@ -99,4 +99,6 @@ #define SO_CNX_ADVICE 53 +#define SCM_TIMESTAMPING_OPT_STATS 54 + #endif /* _ASM_IA64_SOCKET_H */ diff --git a/arch/m32r/include/uapi/asm/socket.h b/arch/m32r/include/uapi/asm/socket.h index 5fe42fc7b6c5d..5853f8e92c20c 100644 --- a/arch/m32r/include/uapi/asm/socket.h +++ b/arch/m32r/include/uapi/asm/socket.h @@ -90,4 +90,6 @@ #define SO_CNX_ADVICE 53 +#define SCM_TIMESTAMPING_OPT_STATS 54 + #endif /* _ASM_M32R_SOCKET_H */ diff --git a/arch/mips/include/uapi/asm/socket.h b/arch/mips/include/uapi/asm/socket.h index 2027240aafbb8..566ecdcb5b4bc 100644 --- a/arch/mips/include/uapi/asm/socket.h +++ b/arch/mips/include/uapi/asm/socket.h @@ -108,4 +108,6 @@ #define SO_CNX_ADVICE 53 +#define SCM_TIMESTAMPING_OPT_STATS 54 + #endif /* _UAPI_ASM_SOCKET_H */ diff --git a/arch/mn10300/include/uapi/asm/socket.h b/arch/mn10300/include/uapi/asm/socket.h index 5129f23a9ee10..0e12527c4b0e6 100644 --- a/arch/mn10300/include/uapi/asm/socket.h +++ b/arch/mn10300/include/uapi/asm/socket.h @@ -90,4 +90,6 @@ #define SO_CNX_ADVICE 53 +#define SCM_TIMESTAMPING_OPT_STATS 54 + #endif /* _ASM_SOCKET_H */ diff --git a/arch/parisc/include/uapi/asm/socket.h b/arch/parisc/include/uapi/asm/socket.h index 9c935d717df94..7a109b73ddf7e 100644 --- a/arch/parisc/include/uapi/asm/socket.h +++ b/arch/parisc/include/uapi/asm/socket.h @@ -89,4 +89,6 @@ #define SO_CNX_ADVICE 0x402E +#define SCM_TIMESTAMPING_OPT_STATS 0x402F + #endif /* _UAPI_ASM_SOCKET_H */ diff --git a/arch/powerpc/include/uapi/asm/socket.h b/arch/powerpc/include/uapi/asm/socket.h index 1672e3398270b..44583a52f8825 100644 --- a/arch/powerpc/include/uapi/asm/socket.h +++ b/arch/powerpc/include/uapi/asm/socket.h @@ -97,4 +97,6 @@ #define SO_CNX_ADVICE 53 +#define SCM_TIMESTAMPING_OPT_STATS 54 + #endif /* _ASM_POWERPC_SOCKET_H */ diff --git a/arch/s390/include/uapi/asm/socket.h b/arch/s390/include/uapi/asm/socket.h index 41b51c2f4f1ba..b24a64cbfeb10 100644 --- a/arch/s390/include/uapi/asm/socket.h +++ b/arch/s390/include/uapi/asm/socket.h @@ -96,4 +96,6 @@ #define SO_CNX_ADVICE 53 +#define SCM_TIMESTAMPING_OPT_STATS 54 + #endif /* _ASM_SOCKET_H */ diff --git a/arch/sparc/include/uapi/asm/socket.h b/arch/sparc/include/uapi/asm/socket.h index 31aede3af0880..a25dc32f5d6a1 100644 --- a/arch/sparc/include/uapi/asm/socket.h +++ b/arch/sparc/include/uapi/asm/socket.h @@ -86,6 +86,8 @@ #define SO_CNX_ADVICE 0x0037 +#define SCM_TIMESTAMPING_OPT_STATS 0x0038 + /* Security levels - as per NRL IPv6 - don't actually do anything */ #define SO_SECURITY_AUTHENTICATION 0x5001 #define SO_SECURITY_ENCRYPTION_TRANSPORT 0x5002 diff --git a/arch/xtensa/include/uapi/asm/socket.h b/arch/xtensa/include/uapi/asm/socket.h index 81435d995e118..9fdbe1fe04738 100644 --- a/arch/xtensa/include/uapi/asm/socket.h +++ b/arch/xtensa/include/uapi/asm/socket.h @@ -101,4 +101,6 @@ #define SO_CNX_ADVICE 53 +#define SCM_TIMESTAMPING_OPT_STATS 54 + #endif /* _XTENSA_SOCKET_H */ diff --git a/include/linux/tcp.h b/include/linux/tcp.h index d5d3bd8143387..00e0ee8f001f4 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -428,4 +428,6 @@ static inline void tcp_saved_syn_free(struct tcp_sock *tp) tp->saved_syn = NULL; } +struct sk_buff *tcp_get_timestamping_opt_stats(const struct sock *sk); + #endif /* _LINUX_TCP_H */ diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/socket.h index 67d632f1743dd..2c748ddad5f87 100644 --- a/include/uapi/asm-generic/socket.h +++ b/include/uapi/asm-generic/socket.h @@ -92,4 +92,6 @@ #define SO_CNX_ADVICE 53 +#define SCM_TIMESTAMPING_OPT_STATS 54 + #endif /* __ASM_GENERIC_SOCKET_H */ diff --git a/include/uapi/linux/net_tstamp.h b/include/uapi/linux/net_tstamp.h index 264e515de16f6..464dcca5ed683 100644 --- a/include/uapi/linux/net_tstamp.h +++ b/include/uapi/linux/net_tstamp.h @@ -25,8 +25,9 @@ enum { SOF_TIMESTAMPING_TX_ACK = (1<<9), SOF_TIMESTAMPING_OPT_CMSG = (1<<10), SOF_TIMESTAMPING_OPT_TSONLY = (1<<11), + SOF_TIMESTAMPING_OPT_STATS = (1<<12), - SOF_TIMESTAMPING_LAST = SOF_TIMESTAMPING_OPT_TSONLY, + SOF_TIMESTAMPING_LAST = SOF_TIMESTAMPING_OPT_STATS, SOF_TIMESTAMPING_MASK = (SOF_TIMESTAMPING_LAST - 1) | SOF_TIMESTAMPING_LAST }; diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h index 2863b661d6e1c..c53de2691cece 100644 --- a/include/uapi/linux/tcp.h +++ b/include/uapi/linux/tcp.h @@ -220,6 +220,14 @@ struct tcp_info { __u64 tcpi_sndbuf_limited; /* Time (usec) limited by send buffer */ }; +/* netlink attributes types for SCM_TIMESTAMPING_OPT_STATS */ +enum { + TCP_NLA_PAD, + TCP_NLA_BUSY, /* Time (usec) busy sending data */ + TCP_NLA_RWND_LIMITED, /* Time (usec) limited by receive window */ + TCP_NLA_SNDBUF_LIMITED, /* Time (usec) limited by send buffer */ +}; + /* for TCP_MD5SIG socket option */ #define TCP_MD5SIG_MAXKEYLEN 80 diff --git a/net/core/skbuff.c b/net/core/skbuff.c index d1d1a5a5ad24d..ea6fa954c7a0d 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -3839,10 +3839,18 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb, if (!skb_may_tx_timestamp(sk, tsonly)) return; - if (tsonly) - skb = alloc_skb(0, GFP_ATOMIC); - else + if (tsonly) { +#ifdef CONFIG_INET + if ((sk->sk_tsflags & SOF_TIMESTAMPING_OPT_STATS) && + sk->sk_protocol == IPPROTO_TCP && + sk->sk_type == SOCK_STREAM) + skb = tcp_get_timestamping_opt_stats(sk); + else +#endif + skb = alloc_skb(0, GFP_ATOMIC); + } else { skb = skb_clone(orig_skb, GFP_ATOMIC); + } if (!skb) return; diff --git a/net/core/sock.c b/net/core/sock.c index 14e6145be33b9..d8c7f8c877ca3 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -854,6 +854,13 @@ int sock_setsockopt(struct socket *sock, int level, int optname, sk->sk_tskey = 0; } } + + if (val & SOF_TIMESTAMPING_OPT_STATS && + !(val & SOF_TIMESTAMPING_OPT_TSONLY)) { + ret = -EINVAL; + break; + } + sk->sk_tsflags = val; if (val & SOF_TIMESTAMPING_RX_SOFTWARE) sock_enable_timestamp(sk, diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index cdde20f49999c..1149b48700a12 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2841,6 +2841,26 @@ void tcp_get_info(struct sock *sk, struct tcp_info *info) } EXPORT_SYMBOL_GPL(tcp_get_info); +struct sk_buff *tcp_get_timestamping_opt_stats(const struct sock *sk) +{ + const struct tcp_sock *tp = tcp_sk(sk); + struct sk_buff *stats; + struct tcp_info info; + + stats = alloc_skb(3 * nla_total_size_64bit(sizeof(u64)), GFP_ATOMIC); + if (!stats) + return NULL; + + tcp_get_info_chrono_stats(tp, &info); + nla_put_u64_64bit(stats, TCP_NLA_BUSY, + info.tcpi_busy_time, TCP_NLA_PAD); + nla_put_u64_64bit(stats, TCP_NLA_RWND_LIMITED, + info.tcpi_rwnd_limited, TCP_NLA_PAD); + nla_put_u64_64bit(stats, TCP_NLA_SNDBUF_LIMITED, + info.tcpi_sndbuf_limited, TCP_NLA_PAD); + return stats; +} + static int do_tcp_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen) { diff --git a/net/socket.c b/net/socket.c index e2584c51aa1fe..e6318943ad070 100644 --- a/net/socket.c +++ b/net/socket.c @@ -693,9 +693,14 @@ void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE) && ktime_to_timespec_cond(shhwtstamps->hwtstamp, tss.ts + 2)) empty = 0; - if (!empty) + if (!empty) { put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPING, sizeof(tss), &tss); + + if (skb->len && (sk->sk_tsflags & SOF_TIMESTAMPING_OPT_STATS)) + put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPING_OPT_STATS, + skb->len, skb->data); + } } EXPORT_SYMBOL_GPL(__sock_recv_timestamp);