On Wed, 16 Nov 2022 15:41:55 +1100 David Gibson <david(a)gibson.dropbear.id.au> wrote:In tcp_sock_handler() we split off to handle spliced sockets before checking anything else. However the first steps of the "new connection" path for each case are the same: allocate a connection entry and accept() the connection. Remove this duplication by making tcp_conn_from_sock() handle both spliced and non-spliced cases, with help from more specific tcp_tap_conn_from_sock and tcp_splice_conn_from_sock functions for the later stages which differ. Signed-off-by: David Gibson <david(a)gibson.dropbear.id.au> --- tcp.c | 68 ++++++++++++++++++++++++++++++++++------------------ tcp_splice.c | 58 +++++++++++++++++++++++--------------------- tcp_splice.h | 4 ++++ 3 files changed, 80 insertions(+), 50 deletions(-) diff --git a/tcp.c b/tcp.c index 72d3b49..e66a82a 100644 --- a/tcp.c +++ b/tcp.c @@ -2753,28 +2753,19 @@ static void tcp_connect_finish(struct ctx *c, struct tcp_tap_conn *conn) } /** - * tcp_conn_from_sock() - Handle new connection request from listening socket + * tcp_tap_conn_from_sock() - Initialize state for non-spliced connection * @c: Execution context * @ref: epoll reference of listening socket + * @conn: connection structure to initialize + * @s: Accepted socket + * @sa: Peer socket address (from accept()) * @now: Current timestamp */ -static void tcp_conn_from_sock(struct ctx *c, union epoll_ref ref, - const struct timespec *now) +static void tcp_tap_conn_from_sock(struct ctx *c, union epoll_ref ref, + struct tcp_tap_conn *conn, int s, + struct sockaddr *sa, + const struct timespec *now) { - struct sockaddr_storage sa; - struct tcp_tap_conn *conn; - socklen_t sl; - int s; - - if (c->tcp.conn_count >= TCP_MAX_CONNS) - return; - - sl = sizeof(sa); - s = accept4(ref.r.s, (struct sockaddr *)&sa, &sl, SOCK_NONBLOCK); - if (s < 0) - return; - - conn = CONN(c->tcp.conn_count++); conn->c.spliced = false; conn->sock = s; conn->timer = -1; @@ -2784,7 +2775,7 @@ static void tcp_conn_from_sock(struct ctx *c, union epoll_ref ref, if (ref.r.p.tcp.tcp.v6) { struct sockaddr_in6 sa6; - memcpy(&sa6, &sa, sizeof(sa6)); + memcpy(&sa6, sa, sizeof(sa6)); if (IN6_IS_ADDR_LOOPBACK(&sa6.sin6_addr) || IN6_ARE_ADDR_EQUAL(&sa6.sin6_addr, &c->ip6.addr_seen) || @@ -2813,7 +2804,7 @@ static void tcp_conn_from_sock(struct ctx *c, union epoll_ref ref, } else { struct sockaddr_in sa4; - memcpy(&sa4, &sa, sizeof(sa4)); + memcpy(&sa4, sa, sizeof(sa4)); memset(&conn->a.a4.zero, 0, sizeof(conn->a.a4.zero)); memset(&conn->a.a4.one, 0xff, sizeof(conn->a.a4.one)); @@ -2846,6 +2837,37 @@ static void tcp_conn_from_sock(struct ctx *c, union epoll_ref ref, tcp_get_sndbuf(conn); } +/** + * tcp_conn_from_sock() - Handle new connection request from listening socket + * @c: Execution context + * @ref: epoll reference of listening socket + * @now: Current timestamp + */ +static void tcp_conn_from_sock(struct ctx *c, union epoll_ref ref, + const struct timespec *now) +{ + struct sockaddr_storage sa; + union tcp_conn *conn; + socklen_t sl; + int s; + + if (c->tcp.conn_count >= TCP_MAX_CONNS) + return; + + sl = sizeof(sa); + s = accept4(ref.r.s, (struct sockaddr *)&sa, &sl, SOCK_NONBLOCK);Combined with 16/32 I'm not sure this is simplifying much -- it looks a bit unnatural there to get the peer address not "directly" from accept4(). On the other hand you drop a few lines -- I'm fine with it either way.+ if (s < 0) + return; + + conn = tc + c->tcp.conn_count++; + + if (ref.r.p.tcp.tcp.splice) + tcp_splice_conn_from_sock(c, ref, &conn->splice, s); + else + tcp_tap_conn_from_sock(c, ref, &conn->tap, s, + (struct sockaddr *)&sa, now); +} + /** * tcp_timer_handler() - timerfd events: close, send ACK, retransmit, or reset * @c: Execution context @@ -2925,13 +2947,13 @@ void tcp_sock_handler(struct ctx *c, union epoll_ref ref, uint32_t events, return; } - if (ref.r.p.tcp.tcp.splice) { - tcp_sock_handler_splice(c, ref, events); + if (ref.r.p.tcp.tcp.listen) { + tcp_conn_from_sock(c, ref, now); return; } - if (ref.r.p.tcp.tcp.listen) { - tcp_conn_from_sock(c, ref, now); + if (ref.r.p.tcp.tcp.splice) { + tcp_sock_handler_splice(c, ref, events); return; } diff --git a/tcp_splice.c b/tcp_splice.c index 7a06252..7007501 100644 --- a/tcp_splice.c +++ b/tcp_splice.c @@ -501,6 +501,36 @@ static void tcp_splice_dir(struct tcp_splice_conn *conn, int ref_sock, *pipes = *from == conn->a ? conn->pipe_a_b : conn->pipe_b_a; } +/** + * tcp_splice_conn_from_sock() - Initialize state for spliced connection + * @c: Execution context + * @ref: epoll reference of listening socket + * @conn: connection structure to initialize + * @s: Accepted socket + * + * #syscalls:pasta setsockopt + */ +void tcp_splice_conn_from_sock(struct ctx *c, union epoll_ref ref, + struct tcp_splice_conn *conn, int s) +{ + assert(c->mode == MODE_PASTA); + + if (setsockopt(s, SOL_TCP, TCP_QUICKACK, &((int){ 1 }), + sizeof(int))) { + trace("TCP (spliced): failed to set TCP_QUICKACK on %i", + s);This could be indented sanely, now.+ } + + conn->c.spliced = true; + c->tcp.splice_conn_count++; + conn->a = s; + conn->flags = ref.r.p.tcp.tcp.v6 ? SPLICE_V6 : 0; + + if (tcp_splice_new(c, conn, ref.r.p.tcp.tcp.index, + ref.r.p.tcp.tcp.outbound)) + conn_flag(c, conn, CLOSING); +} + /** * tcp_sock_handler_splice() - Handler for socket mapped to spliced connection * @c: Execution context @@ -517,33 +547,7 @@ void tcp_sock_handler_splice(struct ctx *c, union epoll_ref ref, uint32_t *seq_read, *seq_write; struct tcp_splice_conn *conn; - if (ref.r.p.tcp.tcp.listen) { - int s; - - if (c->tcp.conn_count >= TCP_MAX_CONNS) - return; - - if ((s = accept4(ref.r.s, NULL, NULL, SOCK_NONBLOCK)) < 0) - return; - - if (setsockopt(s, SOL_TCP, TCP_QUICKACK, &((int){ 1 }), - sizeof(int))) { - trace("TCP (spliced): failed to set TCP_QUICKACK on %i", - s); - } - - conn = CONN(c->tcp.conn_count++); - conn->c.spliced = true; - c->tcp.splice_conn_count++; - conn->a = s; - conn->flags = ref.r.p.tcp.tcp.v6 ? SPLICE_V6 : 0; - - if (tcp_splice_new(c, conn, ref.r.p.tcp.tcp.index, - ref.r.p.tcp.tcp.outbound)) - conn_flag(c, conn, CLOSING); - - return; - } + assert(!ref.r.p.tcp.tcp.listen); conn = CONN(ref.r.p.tcp.tcp.index); diff --git a/tcp_splice.h b/tcp_splice.h index 22024d6..f9462ae 100644 --- a/tcp_splice.h +++ b/tcp_splice.h @@ -6,8 +6,12 @@ #ifndef TCP_SPLICE_H #define TCP_SPLICE_H +struct tcp_splice_conn; + void tcp_sock_handler_splice(struct ctx *c, union epoll_ref ref, uint32_t events); +void tcp_splice_conn_from_sock(struct ctx *c, union epoll_ref ref, + struct tcp_splice_conn *conn, int s); void tcp_splice_init(struct ctx *c); #endif /* TCP_SPLICE_H */-- Stefano