1 /* Copyright (c) 2014, 2021, Oracle and/or its affiliates. 2 3 This program is free software; you can redistribute it and/or modify 4 it under the terms of the GNU General Public License, version 2.0, 5 as published by the Free Software Foundation. 6 7 This program is also distributed with certain software (including 8 but not limited to OpenSSL) that is licensed under separate terms, 9 as designated in a particular file or component or in included license 10 documentation. The authors of MySQL hereby grant you an additional 11 permission to link the program and your derivative works with the 12 separately licensed software that they have included with MySQL. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License, version 2.0, for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with this program; if not, write to the Free Software 21 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ 22 23 #ifndef SEMISYNC_MASTER_ACK_RECEIVER_DEFINED 24 #define SEMISYNC_MASTER_ACK_RECEIVER_DEFINED 25 26 #include <vector> 27 #include "my_global.h" 28 #include "my_thread.h" 29 #include "sql_class.h" 30 31 struct Slave 32 { 33 uint32_t thread_id; 34 Vio vio; 35 uint server_id; 36 bool net_compress; 37 sock_fdSlave38 my_socket sock_fd() const { return vio.mysql_socket.fd; } 39 }; 40 41 typedef std::vector<Slave> Slave_vector; 42 typedef Slave_vector::iterator Slave_vector_it; 43 44 /** 45 Ack_receiver is responsible to control ack receive thread and maintain 46 slave information used by ack receive thread. 47 48 There are mainly four operations on ack receive thread: 49 start: start ack receive thread 50 stop: stop ack receive thread 51 add_slave: maintain a new semisync slave's information 52 remove_slave: remove a semisync slave's information 53 */ 54 class Ack_receiver : public ReplSemiSyncBase 55 { 56 public: 57 Ack_receiver(); 58 ~Ack_receiver(); 59 60 /** 61 Notify ack receiver to receive acks on the dump session. 62 63 It adds the given dump thread into the slave list and wakes 64 up ack thread if it is waiting for any slave coming. 65 66 @param[in] thd THD of a dump thread. 67 68 @return it return false if succeeds, otherwise true is returned. 69 */ 70 bool add_slave(THD *thd); 71 72 /** 73 Notify ack receiver not to receive ack on the dump session. 74 75 it removes the given dump thread from slave list. 76 77 @param[in] thd THD of a dump thread. 78 */ 79 void remove_slave(THD *thd); 80 81 /** 82 Start ack receive thread 83 84 @return it return false if succeeds, otherwise true is returned. 85 */ 86 bool start(); 87 88 /** 89 Stop ack receive thread 90 */ 91 void stop(); 92 93 /** 94 The core of ack receive thread. 95 96 It monitors all slaves' sockets and receives acks when they come. 97 */ 98 void run(); 99 setTraceLevel(unsigned long trace_level)100 void setTraceLevel(unsigned long trace_level) 101 { 102 trace_level_= trace_level; 103 } 104 init()105 bool init() 106 { 107 setTraceLevel(rpl_semi_sync_master_trace_level); 108 if (rpl_semi_sync_master_enabled) 109 return start(); 110 return false; 111 } 112 private: 113 enum status {ST_UP, ST_DOWN, ST_STOPPING}; 114 uint8 m_status; 115 /* 116 Protect m_status, m_slaves_changed and m_slaves. ack thread and other 117 session may access the variables at the same time. 118 */ 119 mysql_mutex_t m_mutex; 120 mysql_cond_t m_cond; 121 /* If slave list is updated(add or remove). */ 122 bool m_slaves_changed; 123 Slave_vector m_slaves; 124 my_thread_handle m_pid; 125 126 /* Declare them private, so no one can copy the object. */ 127 Ack_receiver(const Ack_receiver &ack_receiver); 128 Ack_receiver& operator=(const Ack_receiver &ack_receiver); 129 130 void set_stage_info(const PSI_stage_info &stage); 131 void wait_for_slave_connection(); 132 }; 133 134 extern Ack_receiver ack_receiver; 135 #endif 136