Auto merge fix for Bug#49020

mysql-test/suite/rpl/r/rpl_semi_sync_event.result

+stop slave;
+drop table if exists t1,t2,t3,t4,t5,t6,t7,t8,t9;
+reset master;
+reset slave;
+drop table if exists t1,t2,t3,t4,t5,t6,t7,t8,t9;
+start slave;
+include/stop_slave.inc
+include/start_slave.inc
+SET GLOBAL event_scheduler = ON;
+CREATE TABLE t1 (i INT NOT NULL AUTO_INCREMENT PRIMARY KEY, f varchar(8)) ENGINE=ENGINE_TYPE;
+INSERT INTO t1 (f) VALUES ('a'),('a'),('a'),('a'),('a');
+INSERT INTO t1 SELECT i+5, f FROM t1;
+INSERT INTO t1 SELECT i+10, f FROM t1;
+CREATE EVENT ev1 ON SCHEDULE EVERY 1 SECOND
+DO INSERT INTO t1 VALUES (SLEEP(5),CONCAT('ev1_',CONNECTION_ID()));
+CREATE EVENT ev2 ON SCHEDULE EVERY 1 SECOND
+DO INSERT INTO t1 VALUES (SLEEP(5),CONCAT('ev2_',CONNECTION_ID()));
+STOP SLAVE IO_THREAD;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 20;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 19;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 18;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 17;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 16;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 15;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 14;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 13;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 12;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 11;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 10;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 9;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 8;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 7;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 6;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 5;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 4;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 3;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 2;
+UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = 1;
+SET GLOBAL event_scheduler = OFF;
+include/stop_slave.inc
+UNINSTALL PLUGIN rpl_semi_sync_slave;
+UNINSTALL PLUGIN rpl_semi_sync_master;
+include/start_slave.inc
+DROP EVENT ev1;
+DROP EVENT ev2;
+DROP TABLE t1;

mysql-test/suite/rpl/t/rpl_semi_sync_event-master.opt

+$SEMISYNC_PLUGIN_OPT --max-connections=23

mysql-test/suite/rpl/t/rpl_semi_sync_event-slave.opt

+$SEMISYNC_PLUGIN_OPT

mysql-test/suite/rpl/t/rpl_semi_sync_event.test

+source include/have_semisync_plugin.inc;
+source include/not_embedded.inc;
+source include/master-slave.inc;
+source include/have_innodb.inc;
+
+let $engine_type= InnoDB;
+
+# Suppress warnings that might be generated during the test
+disable_query_log;
+connection master;
+call mtr.add_suppression("Timeout waiting for reply of binlog");
+call mtr.add_suppression("Semi-sync master .* waiting for slave reply");
+call mtr.add_suppression("Read semi-sync reply");
+connection slave;
+call mtr.add_suppression("Master server does not support semi-sync");
+call mtr.add_suppression("Semi-sync slave .* reply");
+enable_query_log;
+
+connection master;
+disable_query_log;
+let $value = query_get_value(show variables like 'rpl_semi_sync_master_enabled', Value, 1);
+if (`select '$value' = 'No such row'`)
+{
+    set sql_log_bin=0;
+    eval INSTALL PLUGIN rpl_semi_sync_master SONAME '$SEMISYNC_MASTER_PLUGIN';
+    SET GLOBAL rpl_semi_sync_master_enabled = 1;
+    set sql_log_bin=1;
+}
+enable_query_log;
+
+connection slave;
+source include/stop_slave.inc;
+
+disable_query_log;
+let $value= query_get_value(show variables like 'rpl_semi_sync_slave_enabled', Value, 1);
+if (`select '$value' = 'No such row'`)
+{
+    set sql_log_bin=0;
+    eval INSTALL PLUGIN rpl_semi_sync_slave SONAME '$SEMISYNC_SLAVE_PLUGIN';
+    SET GLOBAL rpl_semi_sync_slave_enabled = 1;
+    set sql_log_bin=1;
+}
+enable_query_log;
+
+source include/start_slave.inc;
+
+connection master;
+SET GLOBAL event_scheduler = ON;
+
+replace_result $engine_type ENGINE_TYPE;
+eval CREATE TABLE t1 (i INT NOT NULL AUTO_INCREMENT PRIMARY KEY, f varchar(8)) ENGINE=$engine_type;
+INSERT INTO t1 (f) VALUES ('a'),('a'),('a'),('a'),('a');
+INSERT INTO t1 SELECT i+5, f FROM t1;
+INSERT INTO t1 SELECT i+10, f FROM t1;
+
+CREATE EVENT ev1 ON SCHEDULE EVERY 1 SECOND
+DO INSERT INTO t1 VALUES (SLEEP(5),CONCAT('ev1_',CONNECTION_ID()));
+CREATE EVENT ev2 ON SCHEDULE EVERY 1 SECOND
+DO INSERT INTO t1 VALUES (SLEEP(5),CONCAT('ev2_',CONNECTION_ID()));
+
+connection slave;
+STOP SLAVE IO_THREAD;
+
+connection master;
+let $run = 20;
+while ($run)
+{
+        connect (m$run,localhost,root,,);
+        connection m$run;
+        send;
+        eval UPDATE t1 SET f = CONCAT('up_',CONNECTION_ID()) WHERE i = $run;
+        connection master;
+        dec $run;
+}
+
+connection master;
+SET GLOBAL event_scheduler = OFF;
+
+let $run = 20;
+while ($run)
+{
+	connection m$run;
+	reap;
+        disconnect m$run;
+        dec $run;
+}
+
+#
+# Clean up
+#
+connection slave;
+source include/stop_slave.inc;
+
+disable_warnings;
+UNINSTALL PLUGIN rpl_semi_sync_slave;
+
+connection master;
+UNINSTALL PLUGIN rpl_semi_sync_master;
+enable_warnings;
+
+connection slave;
+source include/start_slave.inc;
+
+connection master;
+DROP EVENT ev1;
+DROP EVENT ev2;
+DROP TABLE t1;
+sync_slave_with_master;

plugin/semisync/semisync_master.cc

@@ -63,29 +63,14 @@ static int gettimeofday(struct timeval *tv, void *tz)
  *
  ******************************************************************************/
 
-ActiveTranx::ActiveTranx(int max_connections,
-			 pthread_mutex_t *lock,
+ActiveTranx::ActiveTranx(pthread_mutex_t *lock,
 			 unsigned long trace_level)
-  : Trace(trace_level), num_transactions_(max_connections),
-    num_entries_(max_connections << 1),
+  : Trace(trace_level),
+    num_entries_(max_connections << 1), /* Transaction hash table size
+                                         * is set to double the size
+                                         * of max_connections */
     lock_(lock)
 {
-  /* Allocate the memory for the array */
-  node_array_ = new TranxNode[num_transactions_];
-  for (int idx = 0; idx < num_transactions_; ++idx)
-  {
-    node_array_[idx].log_pos_     = 0;
-    node_array_[idx].hash_next_   = NULL;
-    node_array_[idx].next_        = node_array_ + idx + 1;
-
-    node_array_[idx].log_name_    = new char[FN_REFLEN];
-    node_array_[idx].log_name_[0] = '\x0';
-  }
-  node_array_[num_transactions_-1].next_ = NULL;
-
-  /* All nodes in the array go to the pool initially. */
-  free_pool_ = node_array_;
-
   /* No transactions are in the list initially. */
   trx_front_ = NULL;
   trx_rear_  = NULL;
@@ -95,24 +80,13 @@ ActiveTranx::ActiveTranx(int max_connections,
   for (int idx = 0; idx < num_entries_; ++idx)
     trx_htb_[idx] = NULL;
 
-  sql_print_information("Semi-sync replication initialized for %d "
-                        "transactions.", num_transactions_);
+  sql_print_information("Semi-sync replication initialized for transactions.");
 }
 
 ActiveTranx::~ActiveTranx()
 {
-  for (int idx = 0; idx < num_transactions_; ++idx)
-  {
-    delete [] node_array_[idx].log_name_;
-    node_array_[idx].log_name_ = NULL;
-  }
-
-  delete [] node_array_;
   delete [] trx_htb_;
-
-  node_array_       = NULL;
   trx_htb_          = NULL;
-  num_transactions_ = 0;
   num_entries_      = 0;
 }
 
@@ -143,26 +117,21 @@ unsigned int ActiveTranx::get_hash_value(const char *log_file_name,
 
 ActiveTranx::TranxNode* ActiveTranx::alloc_tranx_node()
 {
-  TranxNode *ptr = free_pool_;
-
-  if (free_pool_)
-  {
-    free_pool_ = free_pool_->next_;
-    ptr->next_ = NULL;
-    ptr->hash_next_ = NULL;
-  }
-  else
+  MYSQL_THD thd= (MYSQL_THD)current_thd;
+  /* The memory allocated for TranxNode will be automatically freed at
+     the end of the command of current THD. And because
+     ha_autocommit_or_rollback() will always be called before that, so
+     we are sure that the node will be removed from the active list
+     before it get freed. */
+  TranxNode *trx_node = (TranxNode *)thd_alloc(thd, sizeof(TranxNode));
+  if (trx_node)
   {
-    /*
-      free_pool should never be NULL here, because we have
-      max_connections number of pre-allocated nodes.
-    */
-    sql_print_error("You have encountered a semi-sync bug (free_pool == NULL), "
-                    "please report to http://bugs.mysql.com");
-    assert(free_pool_);
+    trx_node->log_name_[0] = '\0';
+    trx_node->log_pos_= 0;
+    trx_node->next_= 0;
+    trx_node->hash_next_= 0;
   }
-
-  return ptr;
+  return trx_node;
 }
 
 int ActiveTranx::compare(const char *log_file_name1, my_off_t log_file_pos1,
@@ -306,8 +275,6 @@ int ActiveTranx::clear_active_tranx_nodes(const char *log_file_name,
     /* Clear the active transaction list. */
     if (trx_front_ != NULL)
     {
-      trx_rear_->next_ = free_pool_;
-      free_pool_ = trx_front_;
       trx_front_ = NULL;
       trx_rear_  = NULL;
     }
@@ -326,11 +293,6 @@ int ActiveTranx::clear_active_tranx_nodes(const char *log_file_name,
     {
       next_node = curr_node->next_;
 
-      /* Put the node in the memory pool. */
-      curr_node->next_ = free_pool_;
-      free_pool_       = curr_node;
-      n_frees++;
-
       /* Remove the node from the hash table. */
       unsigned int hash_val = get_hash_value(curr_node->log_name_, curr_node->log_pos_);
       TranxNode **hash_ptr = &(trx_htb_[hash_val]);
@@ -391,8 +353,7 @@ ReplSemiSyncMaster::ReplSemiSyncMaster()
     wait_file_pos_(0),
     master_enabled_(false),
     wait_timeout_(0L),
-    state_(0),
-    max_transactions_(0L)
+    state_(0)
 {
   strcpy(reply_file_name_, "");
   strcpy(wait_file_name_, "");
@@ -413,7 +374,6 @@ int ReplSemiSyncMaster::initObject()
   /* References to the parameter works after set_options(). */
   setWaitTimeout(rpl_semi_sync_master_timeout);
   setTraceLevel(rpl_semi_sync_master_trace_level);
-  max_transactions_ = (int)max_connections;
 
   /* Mutex initialization can only be done after MY_INIT(). */
   pthread_mutex_init(&LOCK_binlog_, MY_MUTEX_INIT_FAST);
@@ -436,9 +396,7 @@ int ReplSemiSyncMaster::enableMaster()
 
   if (!getMasterEnabled())
   {
-    active_tranxs_ = new ActiveTranx(max_connections,
-				     &LOCK_binlog_,
-				     trace_level_);
+    active_tranxs_ = new ActiveTranx(&LOCK_binlog_, trace_level_);
     if (active_tranxs_ != NULL)
     {
       commit_file_name_inited_ = false;

plugin/semisync/semisync_master.h

@@ -23,31 +23,26 @@
 /**
    This class manages memory for active transaction list.
 
-   We record each active transaction with a TranxNode.  Because each
-   session can only have only one open transaction, the total active
-   transaction nodes can not exceed the maximum sessions.  Currently
-   in MySQL, sessions are the same as connections.
+   We record each active transaction with a TranxNode, each session
+   can have only one open transaction. Because of EVENT, the total
+   active transaction nodes can exceed the maximum allowed
+   connections.
 */
 class ActiveTranx
   :public Trace {
 private:
   struct TranxNode {
-    char             *log_name_;
+    char             log_name_[FN_REFLEN];
     my_off_t          log_pos_;
     struct TranxNode *next_;            /* the next node in the sorted list */
     struct TranxNode *hash_next_;    /* the next node during hash collision */
   };
 
-  /* The following data structure maintains an active transaction list. */
-  TranxNode       *node_array_;
-  TranxNode       *free_pool_;
-
   /* These two record the active transaction list in sort order. */
   TranxNode       *trx_front_, *trx_rear_;
 
   TranxNode      **trx_htb_;        /* A hash table on active transactions. */
 
-  int              num_transactions_;               /* maximum transactions */
   int              num_entries_;              /* maximum hash table entries */
   pthread_mutex_t *lock_;                                     /* mutex lock */
 
@@ -74,8 +69,7 @@ private:
   }
 
 public:
-  ActiveTranx(int max_connections, pthread_mutex_t *lock,
-	      unsigned long trace_level);
+  ActiveTranx(pthread_mutex_t *lock, unsigned long trace_level);
   ~ActiveTranx();
 
   /* Insert an active transaction node with the specified position.
@@ -177,11 +171,6 @@ class ReplSemiSyncMaster
 
   bool            state_;                    /* whether semi-sync is switched */
 
-  /* The number of maximum active transactions.  This should be the same as
-   * maximum connections because MySQL does not do connection sharing now.
-   */
-  int             max_transactions_;
-
   void lock();
   void unlock();
   void cond_broadcast();

sql/rpl_handler.cc

@@ -137,28 +137,53 @@ void delegates_destroy()
  */
 #define FOREACH_OBSERVER(r, f, thd, args)                               \
   param.server_id= thd->server_id;                                      \
+  /*
+     Use a struct to make sure that they are allocated adjacent, check
+     delete_dynamic().
+  */                                                                    \
+  struct {                                                              \
+    DYNAMIC_ARRAY plugins;                                              \
+    /* preallocate 8 slots */                                           \
+    plugin_ref plugins_buffer[8];                                       \
+  } s;                                                                  \
+  DYNAMIC_ARRAY *plugins= &s.plugins;                                   \
+  plugin_ref *plugins_buffer= s.plugins_buffer;                         \
+  my_init_dynamic_array2(plugins, sizeof(plugin_ref),                   \
+                         plugins_buffer, 8, 8);                         \
   read_lock();                                                          \
   Observer_info_iterator iter= observer_info_iter();                    \
   Observer_info *info= iter++;                                          \
   for (; info; info= iter++)                                            \
   {                                                                     \
     plugin_ref plugin=                                                  \
-      my_plugin_lock(thd, &info->plugin);                               \
+      my_plugin_lock(0, &info->plugin);                                 \
     if (!plugin)                                                        \
     {                                                                   \
-      r= 1;                                                             \
+      /* plugin is not intialized or deleted, this is not an error */   \
+      r= 0;                                                             \
       break;                                                            \
     }                                                                   \
+    insert_dynamic(plugins, (uchar *)&plugin);                          \
     if (((Observer *)info->observer)->f                                 \
         && ((Observer *)info->observer)->f args)                        \
     {                                                                   \
       r= 1;                                                             \
-      plugin_unlock(thd, plugin);                                       \
+      sql_print_error("Run function '" #f "' in plugin '%s' failed",    \
+                      info->plugin_int->name.str);                      \
       break;                                                            \
     }                                                                   \
-    plugin_unlock(thd, plugin);                                         \
   }                                                                     \
-  unlock()
+  unlock();                                                             \
+  /* 
+     Unlock plugins should be done after we released the Delegate lock
+     to avoid possible deadlock when this is the last user of the
+     plugin, and when we unlock the plugin, it will try to
+     deinitialize the plugin, which will try to lock the Delegate in
+     order to remove the observers.
+  */                                                                    \
+  plugin_unlock_list(0, (plugin_ref*)plugins->buffer,                   \
+                     plugins->elements);                                \
+  delete_dynamic(plugins)
 
 
 int Trans_delegate::after_commit(THD *thd, bool all)