MDEV-13564 follow-up: Remove dead code

In MariaDB 10.4.0, commit 09af00cbde1d62dfda574dee10e5c0fd240c3f7f
removed the crash-upgrade logic for the MariaDB 10.2
innodb_safe_truncate=OFF TRUNCATE TABLE (which was the only option
between MariaDB 10.2.2 and 10.2.18), but failed to adjust some
comments and code.

buf_page_io_complete(): Remove a bogus comment about TRUNCATE.

dict_recreate_index_tree(): Unused function; remove.

fil_space_t::stop_new_ops: Clarify the comment.

fil_space_acquire_low(): Remove a bogus comment about TRUNCATE.

fil_check_pending_ops(), fil_check_pending_io(): Adjust a warning message.
This code is only invoked as part of DISCARD TABLESPACE or DROP TABLE.
DROP TABLE is internally used as part of ALTER TABLE, OPTIMIZE TABLE,
or TRUNCATE TABLE.

RemoteDatafile::create_link_file(): Clarify a comment.

ibuf_delete_for_discarded_space(): Clarify the function comment.

dict_table_x_lock_indexes(), dict_table_x_unlock_indexes():
Merge with the only remaining caller, row_quiesce_set_state().

page_create_zip(): Remove a bogus comment about TRUNCATE.

1 files changed, 11 insertions, 4 deletions

diff --git a/storage/innobase/row/row0quiesce.cc b/storage/innobase/row/row0quiesce.cc
index 192545192d4..02c8c495e88 100644
--- a/storage/innobase/row/row0quiesce.cc
+++ b/storage/innobase/row/row0quiesce.cc
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 2012, 2016, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2017, 2018, MariaDB Corporation.
+Copyright (c) 2017, 2019, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -669,8 +669,11 @@ row_quiesce_set_state(
 	}
 
 	row_mysql_lock_data_dictionary(trx);
-
-	dict_table_x_lock_indexes(table);
+	for (dict_index_t* index = dict_table_get_first_index(table);
+	     index != NULL;
+	     index = dict_table_get_next_index(index)) {
+		rw_lock_x_lock(&index->lock);
+	}
 
 	switch (state) {
 	case QUIESCE_START:
@@ -687,7 +690,11 @@ row_quiesce_set_state(
 
 	table->quiesce = state;
 
-	dict_table_x_unlock_indexes(table);
+	for (dict_index_t* index = dict_table_get_first_index(table);
+	     index != NULL;
+	     index = dict_table_get_next_index(index)) {
+		rw_lock_x_unlock(&index->lock);
+	}
 
 	row_mysql_unlock_data_dictionary(trx);