Glusterfs之rpc模塊源碼分析(中）之Glusterfs的rpc模塊實現（2）

 1         this = THIS;//取得本線程的xlator列表
 2 
 3         cli_rpc_prog = &cli_prog;//設置rpc調用過程集合（許多函數）
 4 
 5         options = dict_new ();//新建一個字典數據結構用于存放選項信息
 6 
 7         ret = dict_set_str (options, "remote-host", state->remote_host);//設置host
 8 
 9         if (state->remote_port)
10 
11                 port = state->remote_port;
12 
13         ret = dict_set_int32 (options, "remote-port", port);//設置端口號
14 
15         ret = dict_set_str (options, "transport.address-family", "inet");//設置協議族為inet
16 
17         rpc = rpc_clnt_new (options, this->ctx, this->name);//新建一個rpc客戶端對象
18 
19         ret = rpc_clnt_register_notify (rpc, cli_rpc_notify, this);//注冊rpc請求通知函數
20 
21         rpc_clnt_start (rpc);//開始rpc

 1         rpc = GF_CALLOC (1, sizeof (*rpc), gf_common_mt_rpcclnt_t);//為客戶端rpc對象分配內存
 2 
 3         pthread_mutex_init (&rpc->lock, NULL);//初始化鎖
 4 
 5         rpc->ctx = ctx;//屬于哪一個ctx
 6 
 7 //新建請求內存池
 8 
 9         rpc->reqpool = mem_pool_new (struct rpc_req, RPC_CLNT_DEFAULT_REQUEST_COUNT);
10 
11         //保存幀數據的內存池
12 
13 rpc->saved_frames_pool = mem_pool_new (struct saved_frame,
14 
15                                               RPC_CLNT_DEFAULT_REQUEST_COUNT);
16 
17         ret = rpc_clnt_connection_init (rpc, ctx, options, name);//初始化rpc請求連接
18 
19         rpc = rpc_clnt_ref (rpc);//客戶端對象引用計數加1
20 
21         INIT_LIST_HEAD (&rpc->programs);//初始化程序集的鏈表

 1         pthread_mutex_init (&clnt->conn.lock, NULL);//初始化鎖
 2 
 3       conn->trans = rpc_transport_load (ctx, options, name);//裝載協議庫并執行初始化init
 4 
 5         rpc_transport_ref (conn->trans);//增加傳輸層的引用計數
 6 
 7         conn->rpc_clnt = clnt;//連接對象屬于哪一個客戶端對象
 8 
 9         ret = rpc_transport_register_notify (conn->trans, rpc_clnt_notify, conn);//注冊通知函數
10 
11        conn->saved_frames = saved_frames_new ();//新建一個保存幀數據的對象

1 rpc_clnt_reconnect (conn->trans);

 1       pthread_mutex_lock (&conn->lock);//初始化鎖
 2 
 3         {
 4 
 5                 if (conn->reconnect)//如果重新鏈接正在進行
 6 
 7                         gf_timer_call_cancel (clnt->ctx, conn->reconnect);//取消正在的鏈接
 8 
 9                 conn->reconnect = 0;//初始化為0
10 
11  
12 
13                 if (conn->connected == 0) {//還沒有完成鏈接
14 
15                         tv.tv_sec = 3;//時間三秒
16 
17 //發起傳輸層的鏈接
18 
19                         ret = rpc_transport_connect (trans, conn->config.remote_port);
20 
21 //設置重鏈接對象
22 
23                         conn->reconnect = gf_timer_call_after (clnt->ctx, tv,
24 
25                                                      rpc_clnt_reconnect, trans);
26 
27                 } 
28 
29         }
30 
31         pthread_mutex_unlock (&conn->lock);//解鎖
32 
33         if ((ret == -1) && (errno != EINPROGRESS) && (clnt->notifyfn)) {
34 
35 //建立鏈接失敗就通知rpc客戶端對象（調用通知函數）
36 
37                 clnt->notifyfn (clnt, clnt->mydata, RPC_CLNT_DISCONNECT, NULL);
38 
39         }

 1 //得到客戶端協議族相關信息
 2 
 3         ret = socket_client_get_remote_sockaddr (this, SA (&sockaddr), &sockaddr_len, &sa_family)
 4 
 5         if (port > 0)
 6 
 7                 ((struct sockaddr_in *) (&sockaddr))->sin_port = htons (port);//端口字節序轉換
 8 
 9         pthread_mutex_lock (&priv->lock);
10 
11         {
12 
13                 memcpy (&this->peerinfo.sockaddr, &sockaddr, sockaddr_len);//賦值sockaddr信息
14 
15                 this->peerinfo.sockaddr_len = sockaddr_len;//地址長度保存
16 
17                 priv->sock = socket (sa_family, SOCK_STREAM, 0);//創建socket
18 
19                 setsockopt (priv->sock, SOL_SOCKET, SO_RCVBUF, &priv->windowsize,
20 
21                                 sizeof (priv->windowsize)) < 0) ;//設置接收的系統緩沖區
22 
23                 setsockopt (priv->sock, SOL_SOCKET, SO_SNDBUF, &priv->windowsize,
24 
25                                 sizeof (priv->windowsize)) < 0);//發送緩沖區設置
26 
27                 if (priv->nodelay) {
28 
29                         ret = __socket_nodelay (priv->sock);//設置是否延遲發送（等待一個完整的）
30 
31                  }
32 
33                 if (!priv->bio) {
34 
35                         ret = __socket_nonblock (priv->sock);//設置非阻塞
36 
37                 }
38 
39                 if (priv->keepalive) {
40 
41                         ret = __socket_keepalive (priv->sock, priv->keepaliveintvl,
42 
43                                                   priv->keepaliveidle);//保存鏈接活動
44 
45                 }
46 
47                 SA (&this->myinfo.sockaddr)->sa_family =
48 
49                         SA (&this->peerinfo.sockaddr)->sa_family;//保存協議族信息
50 
51                 ret = client_bind (this, SA (&this->myinfo.sockaddr),//根據協議族做適當的綁定
52 
53                                    &this->myinfo.sockaddr_len, priv->sock);
54 
55                 ret = connect (priv->sock, SA (&this->peerinfo.sockaddr),//發起鏈接請求
56 
57                                this->peerinfo.sockaddr_len);
58 
59                priv->connected = 0;
60 
61                 rpc_transport_ref (this);//傳輸對象引用加1
62 
63                 priv->idx = event_register (ctx->event_pool, priv->sock,//注冊epoll讀寫事件
64 
65                                             socket_event_handler, this, 1, 1);
66 
67         }
68 
69         pthread_mutex_unlock (&priv->lock);//解鎖

 1        THIS = this->xl;//取得xlator
 2 
 3         priv = this->private;//取得私有數據
 4 
 5         pthread_mutex_lock (&priv->lock);//加鎖
 6 
 7         {
 8 
 9                 priv->idx = idx;//取得索引下表（對應的socket）
10 
11         }
12 
13         pthread_mutex_unlock (&priv->lock);
14 
15         if (!priv->connected) {//如果鏈接還沒有建立先完成鏈接的建立
16 
17                 ret = socket_connect_finish (this);//完成鏈接建立
18 
19         }
20 
21         if (!ret && poll_out) {//可寫事件處理
22 
23                 ret = socket_event_poll_out (this);
24 
25         }
26 
27         if (!ret && poll_in) {//可讀事件處理
28 
29                 ret = socket_event_poll_in (this);
30 
31         }