3 files changed, 78 insertions, 160 deletions

diff --git a/storage/spider/ha_spider.cc b/storage/spider/ha_spider.cc
index 753d29c23eb..9b3fffcf873 100644
--- a/storage/spider/ha_spider.cc
+++ b/storage/spider/ha_spider.cc
@@ -1180,10 +1180,8 @@ int ha_spider::external_lock(
   backup_error_status();
 
   DBUG_ENTER("ha_spider::external_lock");
-  DBUG_PRINT("info",("spider this=%p", this));
-  DBUG_PRINT("info",("spider lock_type=%x", lock_type));
-  DBUG_PRINT("info", ("spider sql_command=%d", thd_sql_command(thd)));
 
+  /* Beginning of wide_handler setup */
   if (wide_handler->stage == SPD_HND_STAGE_EXTERNAL_LOCK)
   {
     /* Only the stage executor deals with table locks. */
@@ -1194,7 +1192,7 @@ int ha_spider::external_lock(
   }
   else
   {
-    /* Update the stage executor when the stage changes */
+    /* Update the stage executor when the stage changes. */
     wide_handler->stage= SPD_HND_STAGE_EXTERNAL_LOCK;
     wide_handler->stage_executor= this;
   }
@@ -1203,35 +1201,30 @@ int ha_spider::external_lock(
   wide_handler->external_lock_type= lock_type;
   wide_handler->sql_command = thd_sql_command(thd);
 
-  /* We treat BEGIN as if UNLOCK TABLE. */
-  if (wide_handler->sql_command == SQLCOM_BEGIN)
-  {
-    wide_handler->sql_command = SQLCOM_UNLOCK_TABLES;
-  }
-  if (lock_type == F_UNLCK &&
-      wide_handler->sql_command != SQLCOM_UNLOCK_TABLES)
-  {
-    DBUG_RETURN(0);
-  }
-
-  trx = spider_get_trx(thd, TRUE, &error_num);
+  trx= spider_get_trx(thd, TRUE, &error_num);
   if (error_num)
   {
     DBUG_RETURN(error_num);
   }
-  wide_handler->trx = trx;
+  wide_handler->trx= trx;
+  /* End of wide_handler setup */
 
-  /* Question: Why the following if block is necessary? Why here? */
   if (store_error_num)
   {
     DBUG_RETURN(store_error_num);
   }
 
-  DBUG_ASSERT(wide_handler->sql_command != SQLCOM_RENAME_TABLE &&
-              wide_handler->sql_command != SQLCOM_DROP_DB);
+  /* We treat BEGIN as if UNLOCK TABLE. */
+  if (wide_handler->sql_command == SQLCOM_BEGIN)
+  {
+    wide_handler->sql_command = SQLCOM_UNLOCK_TABLES;
+  }
+  const uint sql_command= wide_handler->sql_command;
+
+  DBUG_ASSERT(sql_command != SQLCOM_RENAME_TABLE &&
+              sql_command != SQLCOM_DROP_DB);
 
-  if (wide_handler->sql_command == SQLCOM_DROP_TABLE ||
-      wide_handler->sql_command == SQLCOM_ALTER_TABLE)
+  if (sql_command == SQLCOM_DROP_TABLE || sql_command == SQLCOM_ALTER_TABLE)
   {
     if (trx->locked_connections)
     {
@@ -1242,44 +1235,41 @@ int ha_spider::external_lock(
     DBUG_RETURN(0);
   }
 
-  if (lock_type != F_UNLCK)
+  if (lock_type == F_UNLCK)
+  {
+    if (sql_command != SQLCOM_UNLOCK_TABLES)
+    {
+      DBUG_RETURN(0); /* Unlock remote tables only by UNLOCK TABLES. */
+    }
+    if (!trx->locked_connections)
+    {
+      DBUG_RETURN(0); /* No remote table actually locked by Spider */
+    }
+  }
+  else
   {
     if (unlikely((error_num= spider_internal_start_trx(this))))
     {
       DBUG_RETURN(error_num);
     }
-    if (wide_handler->sql_command != SQLCOM_SELECT &&
-        wide_handler->sql_command != SQLCOM_HA_READ)
+    if (sql_command != SQLCOM_SELECT && sql_command != SQLCOM_HA_READ)
     {
       trx->updated_in_this_trx= TRUE;
-      DBUG_PRINT("info", ("spider trx->updated_in_this_trx=TRUE"));
+    }
+    if (!wide_handler->lock_table_type)
+    {
+      DBUG_RETURN(0); /* No need to actually lock remote tables. */
     }
   }
 
-  if (wide_handler->lock_table_type > 0 ||
-    wide_handler->sql_command == SQLCOM_UNLOCK_TABLES)
+  if (!partition_handler || !partition_handler->handlers)
   {
-    if (wide_handler->sql_command == SQLCOM_UNLOCK_TABLES)
-    {
-      /* lock tables does not call reset() */
-      /* unlock tables does not call store_lock() */
-      wide_handler->lock_table_type = 0;
-    }
+    DBUG_RETURN(lock_tables()); /* Non-partitioned table */
+  }
 
-    /* lock/unlock tables */
-    if (partition_handler && partition_handler->handlers)
-    {
-      for (uint roop_count= 0; roop_count < partition_handler->no_parts;
-           ++roop_count)
-      {
-        if (unlikely((error_num =
-          partition_handler->handlers[roop_count]->lock_tables())))
-        {
-          DBUG_RETURN(error_num);
-        }
-      }
-    }
-    else if (unlikely((error_num= lock_tables())))
+  for (uint i= 0; i < partition_handler->no_parts; ++i)
+  {
+    if (unlikely((error_num= partition_handler->handlers[i]->lock_tables())))
     {
       DBUG_RETURN(error_num);
     }
diff --git a/storage/spider/mysql-test/spider/bugfix/disabled.def b/storage/spider/mysql-test/spider/bugfix/disabled.def
index 68de2b6bfde..e19ea07b76b 100644
--- a/storage/spider/mysql-test/spider/bugfix/disabled.def
+++ b/storage/spider/mysql-test/spider/bugfix/disabled.def
@@ -1,2 +1 @@
 wait_timeout : MDEV-26045
-mdev_27239 : failed with ASAN build
diff --git a/storage/spider/spd_trx.cc b/storage/spider/spd_trx.cc
index 80658012506..657d2c3ebe3 100644
--- a/storage/spider/spd_trx.cc
+++ b/storage/spider/spd_trx.cc
@@ -93,128 +93,51 @@ uchar *spider_trx_ha_get_key(
   DBUG_RETURN((uchar*) trx_ha->table_name);
 }
 
-int spider_free_trx_conn(
-  SPIDER_TRX *trx,
-  bool trx_free
-) {
-  int roop_count;
+/*
+  Try to free the connections held by the given transaction.
+*/
+int spider_free_trx_conn(SPIDER_TRX *trx, bool trx_free)
+{
+  int loop_count= 0;
   SPIDER_CONN *conn;
+  HASH *conn_hash= &trx->trx_conn_hash;
+
   DBUG_ENTER("spider_free_trx_conn");
-  roop_count = 0;
-  if (
-    trx_free ||
-    spider_param_conn_recycle_mode(trx->thd) != 2
-  ) {
-    while ((conn = (SPIDER_CONN*) my_hash_element(&trx->trx_conn_hash,
-      roop_count)))
-    {
-      spider_conn_clear_queue_at_commit(conn);
-      if (conn->table_lock)
-      {
-        DBUG_ASSERT(!trx_free);
-        roop_count++;
-      } else
-        spider_free_conn_from_trx(trx, conn, FALSE, trx_free, &roop_count);
-    }
-    trx->trx_conn_adjustment++;
-  } else {
-    while ((conn = (SPIDER_CONN*) my_hash_element(&trx->trx_conn_hash,
-      roop_count)))
-    {
-      spider_conn_clear_queue_at_commit(conn);
-      if (conn->table_lock)
-      {
-        DBUG_ASSERT(!trx_free);
-      } else
-        conn->error_mode = 1;
-      roop_count++;
-    }
-  }
-#if defined(HS_HAS_SQLCOM) && defined(HAVE_HANDLERSOCKET)
-  roop_count = 0;
-  if (
-    trx_free ||
-    spider_param_hs_r_conn_recycle_mode(trx->thd) != 2
-  ) {
-    while ((conn = (SPIDER_CONN*) my_hash_element(&trx->trx_hs_r_conn_hash,
-      roop_count)))
-    {
-      if (conn->table_lock)
-      {
-        DBUG_ASSERT(!trx_free);
-        roop_count++;
-      } else
-        spider_free_conn_from_trx(trx, conn, FALSE, trx_free, &roop_count);
-    }
-    trx->trx_hs_r_conn_adjustment++;
-  } else {
-    while ((conn = (SPIDER_CONN*) my_hash_element(&trx->trx_hs_r_conn_hash,
-      roop_count)))
-    {
-      if (conn->table_lock)
-      {
-        DBUG_ASSERT(!trx_free);
-      } else
-        conn->error_mode = 1;
-      roop_count++;
-    }
+  DBUG_ASSERT(!trx_free || !trx->locked_connections);
+
+  /* Clear the connection queues in any case. */
+  while ((conn= (SPIDER_CONN *) my_hash_element(conn_hash, loop_count)))
+  {
+    spider_conn_clear_queue_at_commit(conn);
+    loop_count++;
   }
-  roop_count = 0;
-  if (
-    trx_free ||
-    spider_param_hs_w_conn_recycle_mode(trx->thd) != 2
-  ) {
-    while ((conn = (SPIDER_CONN*) my_hash_element(&trx->trx_hs_w_conn_hash,
-      roop_count)))
-    {
-      if (conn->table_lock)
-      {
-        DBUG_ASSERT(!trx_free);
-        roop_count++;
-      } else
-        spider_free_conn_from_trx(trx, conn, FALSE, trx_free, &roop_count);
-    }
-    trx->trx_hs_w_conn_adjustment++;
-  } else {
-    while ((conn = (SPIDER_CONN*) my_hash_element(&trx->trx_hs_w_conn_hash,
-      roop_count)))
+
+  if (trx_free || spider_param_conn_recycle_mode(trx->thd) != 2)
+  {
+    /* Free connections only when no connection is locked. */
+    if (!trx->locked_connections)
     {
-      if (conn->table_lock)
+      loop_count= 0;
+      while ((conn= (SPIDER_CONN *) my_hash_element(conn_hash, loop_count)))
       {
-        DBUG_ASSERT(!trx_free);
-      } else
-        conn->error_mode = 1;
-      roop_count++;
+        spider_free_conn_from_trx(trx, conn, FALSE, trx_free, &loop_count);
+      }
     }
+    trx->trx_conn_adjustment++;
+
+    DBUG_RETURN(0);
   }
-#endif
-#if defined(HS_HAS_SQLCOM) && defined(HAVE_HANDLERSOCKET)
-  if (trx_free)
+
+  loop_count= 0;
+  while ((conn= (SPIDER_CONN *) my_hash_element(conn_hash, loop_count)))
   {
-    while ((conn = (SPIDER_CONN*) my_hash_element(
-      &trx->trx_direct_hs_r_conn_hash, 0)))
-    {
-#ifdef HASH_UPDATE_WITH_HASH_VALUE
-      my_hash_delete_with_hash_value(&trx->trx_direct_hs_r_conn_hash,
-        conn->conn_key_hash_value, (uchar*) conn);
-#else
-      my_hash_delete(&trx->trx_direct_hs_r_conn_hash, (uchar*) conn);
-#endif
-      spider_free_conn(conn);
-    }
-    while ((conn = (SPIDER_CONN*) my_hash_element(
-      &trx->trx_direct_hs_w_conn_hash, 0)))
+    if (!conn->table_lock)
     {
-#ifdef HASH_UPDATE_WITH_HASH_VALUE
-      my_hash_delete_with_hash_value(&trx->trx_direct_hs_w_conn_hash,
-        conn->conn_key_hash_value, (uchar*) conn);
-#else
-      my_hash_delete(&trx->trx_direct_hs_w_conn_hash, (uchar*) conn);
-#endif
-      spider_free_conn(conn);
+      conn->error_mode= 1;
     }
+    loop_count++;
   }
-#endif
+
   DBUG_RETURN(0);
 }
 
@@ -3417,6 +3340,12 @@ int spider_commit(
   trx->bulk_access_conn_first = NULL;
 #endif
 
+  /*
+    We do (almost) nothing if the following two conditions are both met:
+
+    * This is just the end of a statement, not an explicit commit.
+    * The autocommit is OFF or we are in an explicit transaction.
+  */
   if (all || (!thd_test_options(thd, OPTION_NOT_AUTOCOMMIT | OPTION_BEGIN)))
   {
     if (trx->trx_start)