Support the ACK case for bpf timestamping. Add a new sock_ops callback, BPF_SOCK_OPS_TS_ACK_OPT_CB. This callback will occur at the same timestamping point as the user space's SCM_TSTAMP_ACK. The BPF program can use it to get the same SCM_TSTAMP_ACK timestamp without modifying the user-space application. This patch extends txstamp_ack to two bits: 1 stands for SO_TIMESTAMPING mode, 2 bpf extension. Signed-off-by: Jason Xing <kerneljasonxing@xxxxxxxxx> --- include/net/tcp.h | 6 ++++-- include/uapi/linux/bpf.h | 5 +++++ net/core/skbuff.c | 5 ++++- net/dsa/user.c | 2 +- net/ipv4/tcp.c | 2 +- net/socket.c | 2 +- tools/include/uapi/linux/bpf.h | 5 +++++ 7 files changed, 21 insertions(+), 6 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index 4c4dca59352b..2e2fc72e115b 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -958,10 +958,12 @@ struct tcp_skb_cb { __u8 sacked; /* State flags for SACK. */ __u8 ip_dsfield; /* IPv4 tos or IPv6 dsfield */ - __u8 txstamp_ack:1, /* Record TX timestamp for ack? */ +#define TSTAMP_ACK_SK 0x1 +#define TSTAMP_ACK_BPF 0x2 + __u8 txstamp_ack:2, /* Record TX timestamp for ack? */ eor:1, /* Is skb MSG_EOR marked? */ has_rxtstamp:1, /* SKB has a RX timestamp */ - unused:5; + unused:4; __u32 ack_seq; /* Sequence number ACK'd */ union { struct { diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index f70edd067edf..9355d617767f 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -7047,6 +7047,11 @@ enum { * SK_BPF_CB_TX_TIMESTAMPING feature * is on. */ + BPF_SOCK_OPS_TS_ACK_OPT_CB, /* Called when all the skbs in the + * same sendmsg call are acked + * when SK_BPF_CB_TX_TIMESTAMPING + * feature is on. + */ }; /* List of TCP states. There is a build check in net/ipv4/tcp.c to detect diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 4930c43ee77b..9f01dde12e3a 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -5550,7 +5550,7 @@ static bool skb_tstamp_tx_report_so_timestamping(struct sk_buff *skb, return skb_shinfo(skb)->tx_flags & (hwts ? SKBTX_HW_TSTAMP_NOBPF : SKBTX_SW_TSTAMP); case SCM_TSTAMP_ACK: - return TCP_SKB_CB(skb)->txstamp_ack; + return TCP_SKB_CB(skb)->txstamp_ack & TSTAMP_ACK_SK; } return false; @@ -5572,6 +5572,9 @@ static void skb_tstamp_tx_report_bpf_timestamping(struct sk_buff *skb, if (hwts) *skb_hwtstamps(skb) = *hwts; break; + case SCM_TSTAMP_ACK: + op = BPF_SOCK_OPS_TS_ACK_OPT_CB; + break; default: return; } diff --git a/net/dsa/user.c b/net/dsa/user.c index 291ab1b4acc4..794fe553dd77 100644 --- a/net/dsa/user.c +++ b/net/dsa/user.c @@ -897,7 +897,7 @@ static void dsa_skb_tx_timestamp(struct dsa_user_priv *p, { struct dsa_switch *ds = p->dp->ds; - if (!(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)) + if (!(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP_NOBPF)) return; if (!ds->ops->port_txtstamp) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 0d704bda6c41..aa080f7ccea4 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -488,7 +488,7 @@ static void tcp_tx_timestamp(struct sock *sk, struct sockcm_cookie *sockc) sock_tx_timestamp(sk, sockc, &shinfo->tx_flags); if (tsflags & SOF_TIMESTAMPING_TX_ACK) - tcb->txstamp_ack = 1; + tcb->txstamp_ack = TSTAMP_ACK_SK; if (tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) shinfo->tskey = TCP_SKB_CB(skb)->seq + skb->len - 1; } diff --git a/net/socket.c b/net/socket.c index 262a28b59c7f..517de433d4bb 100644 --- a/net/socket.c +++ b/net/socket.c @@ -676,7 +676,7 @@ void __sock_tx_timestamp(__u32 tsflags, __u8 *tx_flags) u8 flags = *tx_flags; if (tsflags & SOF_TIMESTAMPING_TX_HARDWARE) { - flags |= SKBTX_HW_TSTAMP; + flags |= SKBTX_HW_TSTAMP_NOBPF; /* PTP hardware clocks can provide a free running cycle counter * as a time base for virtual clocks. Tell driver to use the diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 7b9652ce7e3c..d3e2988b3b4c 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -7037,6 +7037,11 @@ enum { * SK_BPF_CB_TX_TIMESTAMPING feature * is on. */ + BPF_SOCK_OPS_TS_ACK_OPT_CB, /* Called when all the skbs in the + * same sendmsg call are acked + * when SK_BPF_CB_TX_TIMESTAMPING + * feature is on. + */ }; /* List of TCP states. There is a build check in net/ipv4/tcp.c to detect -- 2.43.5