这里暂不做分析,等后续讲实现的时候再做说明。创建的socket保存在ipv4_tcp_sk里面,这个变量是每个cpu都创建一个,保存在.data..percpu段里面。 注册tcp_sk_ops操作函数,这个操作函数指针主要是为了初始化TCP连接的默认参数,比如重传次数,延时ACK是否开启等。这里也涉及到网络命名空间的知识。Init_net是一个全局参数,...
(sk); __be16 orig_sport, orig_dport; __be32 daddr, nexthop; struct flowi4 *fl4; struct rtable *rt; int err; struct ip_options_rcu *inet_opt; if (addr_len < sizeof(struct sockaddr_in)) return -EINVAL; /*AF_INET是用户调用socket函数创建套接字时传入的参数, 这里校验地址长度和...
tcp_send_syn_data(sk, buff) : tcp_transmit_skb(sk, buff,1, sk->sk_allocation);//发送数据包if(err == -ECONNREFUSED) return err;/*We change tp->snd_nxt after the tcp_transmit_skb() call * in order to make this packet get counted in tcpOutSegs.*/tp->snd_nxt = tp->write_se...
(flag & (FLAG_SND_UNA_ADVANCED | FLAG_NOT_DUP));/* 判断是不是重复的ACK*/booldo_lost = is_dupack || ((flag & FLAG_DATA_SACKED) &&//新来的一个sack(tcp_fackets_out(tp) > tp->reordering));//tcp_fackets_out 返回 "空洞-乱序"的大小, 如果超过3 个 (默认) 就认为丢包。//tp->...
tcpdump 'gateway snup and (port ftp or ftp-data)' 1. 打印所有源地址或目标地址是本地主机的IP数据包 (如果本地网络通过网关连到了另一网络, 则另一网络并不能算作本地网络.(nt: 此句翻译曲折,需补充).localnet 实际使用时要真正替换成本地网络的名字) ...
8 struct flowi4 *fl4; 9 struct rtable *rt; 10 int err; 11 struct ip_options_rcu *inet_opt; 12 struct inet_timewait_death_row *tcp_death_row = &sock_net(sk)->ipv4.tcp_death_row; 13 14 if (addr_len < sizeof(struct sockaddr_in)) ...
Q:支持类似 FlowContext 的特性吗?FlowContext 可扩展吗、可定制吗、可扩展元附加信息吗?(FlowContext 是一种对当前请求处理的上下文) Q:能用一套业务代码,无需任何改动,同时支持多种通信协议:WebSocket、TCP 吗? Q:能用一套业务代码,能轻松切换和扩展不同的通信协议:Protobuf、JSON 吗?
After that the connection is established, data can flow and be accounted for. Are you listening? We need to take a quick second to talk about what a port “listening” means as this is a common point of confusion. For a TCP connection to be accepted, th...
在OpenFlow 时代,传统交换机结合 OpenFlow 协议,通过 Control Plane 正确设置 ASIC 芯片的各种 Flow Table Entries 来控制 Data Plane 的转发行为。但前提是,不能超出 ASIC 芯片原本没有支持的功能范围。可见,OpenFlow 只是从软件层面提供了一种 Control Plane 和 Data Plane 交互的协议,其功能完全受制于硬件的特...
If possible, avoid socket connections with unidirectional data flow. Communications over unidirectional sockets are more easily impacted by the Nagle and delayed acknowledgment algorithms. If the communication follows a request and a response flow, you should use a single socket to do both sends and ...