MDEV-9544 FLUSH [RELAY] LOGS does not rotate logs for a named slavebb-mdev-9544

Problem:- In the case of multisource replication/named slave
when we run "FLUSH LOGS" , it does not flush logs.

Solution:- A new function Master_info_index->flush_all_relay_logs()
is created which will rotate relay logs for all named slave.
This will be called in reload_acl_and_cache function when
connection_name.length == 0

3 files changed, 58 insertions, 3 deletions

diff --git a/sql/rpl_mi.cc b/sql/rpl_mi.cc
index c9dcf7b8fd7..99c9b5e1961 100644
--- a/sql/rpl_mi.cc
+++ b/sql/rpl_mi.cc
@@ -41,7 +41,7 @@ Master_info::Master_info(LEX_STRING *connection_name_arg,
    master_id(0), prev_master_id(0),
    using_gtid(USE_GTID_NO), events_queued_since_last_gtid(0),
    gtid_reconnect_event_skip_count(0), gtid_event_seen(false),
-   in_start_all_slaves(0), in_stop_all_slaves(0),
+   in_start_all_slaves(0), in_stop_all_slaves(0), in_flush_all_relay_logs(0),
    users(0), killed(0)
 {
   host[0] = 0; user[0] = 0; password[0] = 0;
@@ -1980,4 +1980,53 @@ void prot_store_ids(THD *thd, DYNAMIC_ARRAY *ids)
   return;
 }
 
+bool Master_info_index::flush_all_relay_logs()
+{
+  DBUG_ENTER("flush_all_relay_logs");
+  bool result= false;
+  int error= 0;
+  mysql_mutex_lock(&LOCK_active_mi);
+  for (uint i= 0; i< master_info_hash.records; i++)
+  {
+    Master_info *mi;
+    mi= (Master_info *) my_hash_element(&master_info_hash, i);
+    mi->in_flush_all_relay_logs= 0;
+  }
+  for (uint i=0; i < master_info_hash.records;)
+  {
+    Master_info *mi;
+    mi= (Master_info *)my_hash_element(&master_info_hash, i);
+    DBUG_ASSERT(mi);
+
+    if (mi->in_flush_all_relay_logs)
+    {
+      i++;
+      continue;
+    }
+
+    mysql_mutex_unlock(&LOCK_active_mi);
+    mysql_mutex_lock(&mi->data_lock);
+
+    error= rotate_relay_log(mi);
+
+    mysql_mutex_unlock(&mi->data_lock);
+    mi->release();
+
+    mysql_mutex_lock(&LOCK_active_mi);
+
+    if (error)
+    {
+      result= true;
+      break;
+    }
+    mi->in_flush_all_relay_logs= 1;
+  /*   Restart from first element as master_info_hash may have changed */
+    i= 0;
+    continue;
+ }
+  //DBUG_ASSERT(0);
+  mysql_mutex_unlock(&LOCK_active_mi);
+  DBUG_RETURN(result);
+}
+
 #endif /* HAVE_REPLICATION */
diff --git a/sql/rpl_mi.h b/sql/rpl_mi.h
index 31c0f280ac1..d0f6171815c 100644
--- a/sql/rpl_mi.h
+++ b/sql/rpl_mi.h
@@ -302,6 +302,7 @@ class Master_info : public Slave_reporting_capability
   /* gtid_event_seen is false until we receive first GTID event from master. */
   bool gtid_event_seen;
   bool in_start_all_slaves, in_stop_all_slaves;
+  bool in_flush_all_relay_logs;
   uint users;                                   /* Active user for object */
   uint killed;
 
@@ -354,6 +355,7 @@ public:
   bool start_all_slaves(THD *thd);
   bool stop_all_slaves(THD *thd);
   void free_connections();
+  bool flush_all_relay_logs();
 };
 
 
diff --git a/sql/sql_reload.cc b/sql/sql_reload.cc
index 995c4c0a838..376dfeb1542 100644
--- a/sql/sql_reload.cc
+++ b/sql/sql_reload.cc
@@ -181,8 +181,12 @@ bool reload_acl_and_cache(THD *thd, unsigned long long options,
       slave is not likely to have the same connection names.
     */
     tmp_write_to_binlog= 0;
-
-    if (!(mi= (get_master_info(&connection_name,
+    if (connection_name.length == 0)
+    {
+      if (master_info_index->flush_all_relay_logs())
+          *write_to_binlog= -1;
+    }
+    else if (!(mi= (get_master_info(&connection_name,
                                Sql_condition::WARN_LEVEL_ERROR))))
     {
       result= 1;