Bug#50561: ALTER PARTITIONS does not have adequate lock, breaks with

concurrent I_S query

There were two problem:
1) MYSQL_LOCK_IGNORE_FLUSH also ignored name locks
2) there was a race between abort_and_upgrade_locks and
   alter_close_tables
   (i.e. remove_table_from_cache and
    close_data_files_and_morph_locks)

Which allowed the table to be opened with MYSQL_LOCK_IGNORE_FLUSH flag
resulting in renaming a partition that was already in use,
which could cause the table to be unusable.

Solution was to not allow IGNORE_FLUSH to skip waiting for
a named locked table.

And to not release the LOCK_open mutex between the
calls to remove_table_from_cache and
close_data_files_and_morph_locks by merging the functions
abort_and_upgrade_locks and alter_close_tables.

mysql-test/suite/parts/r/partition_debug_sync_innodb.result:
  Bug#50561: ALTER PARTITIONS does not have adequate lock, breaks with
  concurrent I_S query
  
  Added test result
mysql-test/suite/parts/t/partition_debug_sync_innodb-master.opt:
  Bug#50561: ALTER PARTITIONS does not have adequate lock, breaks with
  concurrent I_S query
  
  Added test option
mysql-test/suite/parts/t/partition_debug_sync_innodb.test:
  Bug#50561: ALTER PARTITIONS does not have adequate lock, breaks with
  concurrent I_S query
  
  Added test file
sql/authors.h:
  Bug#50561: ALTER PARTITIONS does not have adequate lock, breaks with
  concurrent I_S query
  
  Time to be acknowledged :)
sql/ha_partition.cc:
  Bug#50561: ALTER PARTITIONS does not have adequate lock, breaks with
  concurrent I_S query
  
  Added DEBUG_SYNC for deterministic testing
sql/mysql_priv.h:
  Bug#50561: ALTER PARTITIONS does not have adequate lock, breaks with
  concurrent I_S query
  
  Renamed function since merging alter_close_tables into
  abort_and_upgrade_lock.
sql/sql_base.cc:
  Bug#50561: ALTER PARTITIONS does not have adequate lock, breaks with
  concurrent I_S query
  
  Changed MYSQL_LOCK_IGNORE_FLUSH to not ignore name locks
  (open_placeholder).
  
  Merged alter_close_tables into abort_and_upgrade_locks
  (and added _and_close_table to the name)
  to not release LOCK_open between remove_table_from_cache
  and close_data_files_and_morph_locks.
  
  Added DEBUG_SYNC for deterministic testing.
sql/sql_partition.cc:
  Bug#50561: ALTER PARTITIONS does not have adequate lock, breaks with
  concurrent I_S query
  
  Removed alter_close_tables, (merged it into
  abort_and_upgrad_lock) so that LOCK_open never is released
  between remove_table_from_cache and
  close_data_files_and_morph_locks.
sql/sql_show.cc:
  Bug#50561: ALTER PARTITIONS does not have adequate lock, breaks with
  concurrent I_S query
  
  Added DEBUG_SYNC for deterministic testing

1 files changed, 3 insertions, 35 deletions

diff --git a/sql/sql_partition.cc b/sql/sql_partition.cc
index 395156dcd63..679d23b49ad 100644
--- a/sql/sql_partition.cc
+++ b/sql/sql_partition.cc
@@ -5955,32 +5955,6 @@ static void alter_partition_lock_handling(ALTER_PARTITION_PARAM_TYPE *lpt)
   }
 }
 
-/*
-  Unlock and close table before renaming and dropping partitions
-  SYNOPSIS
-    alter_close_tables()
-    lpt                        Struct carrying parameters
-  RETURN VALUES
-    0
-*/
-
-static int alter_close_tables(ALTER_PARTITION_PARAM_TYPE *lpt)
-{
-  THD *thd= lpt->thd;
-  const char *db= lpt->db;
-  const char *table_name= lpt->table_name;
-  DBUG_ENTER("alter_close_tables");
-  /*
-    We need to also unlock tables and close all handlers.
-    We set lock to zero to ensure we don't do this twice
-    and we set db_stat to zero to ensure we don't close twice.
-  */
-  pthread_mutex_lock(&LOCK_open);
-  close_data_files_and_morph_locks(thd, db, table_name);
-  pthread_mutex_unlock(&LOCK_open);
-  DBUG_RETURN(0);
-}
-
 
 /*
   Handle errors for ALTER TABLE for partitioning
@@ -6278,9 +6252,7 @@ uint fast_alter_partition_table(THD *thd, TABLE *table,
         write_log_drop_partition(lpt) ||
         ERROR_INJECT_CRASH("crash_drop_partition_3") ||
         (not_completed= FALSE) ||
-        abort_and_upgrade_lock(lpt) || /* Always returns 0 */
-        ERROR_INJECT_CRASH("crash_drop_partition_4") ||
-        alter_close_tables(lpt) ||
+        abort_and_upgrade_lock_and_close_table(lpt) ||
         ERROR_INJECT_CRASH("crash_drop_partition_5") ||
         ((!thd->lex->no_write_to_binlog) &&
          (write_bin_log(thd, FALSE,
@@ -6345,9 +6317,7 @@ uint fast_alter_partition_table(THD *thd, TABLE *table,
         ERROR_INJECT_CRASH("crash_add_partition_2") ||
         mysql_change_partitions(lpt) ||
         ERROR_INJECT_CRASH("crash_add_partition_3") ||
-        abort_and_upgrade_lock(lpt) || /* Always returns 0 */
-        ERROR_INJECT_CRASH("crash_add_partition_4") ||
-        alter_close_tables(lpt) ||
+        abort_and_upgrade_lock_and_close_table(lpt) ||
         ERROR_INJECT_CRASH("crash_add_partition_5") ||
         ((!thd->lex->no_write_to_binlog) &&
          (write_bin_log(thd, FALSE,
@@ -6435,9 +6405,7 @@ uint fast_alter_partition_table(THD *thd, TABLE *table,
         write_log_final_change_partition(lpt) ||
         ERROR_INJECT_CRASH("crash_change_partition_4") ||
         (not_completed= FALSE) ||
-        abort_and_upgrade_lock(lpt) || /* Always returns 0 */
-        ERROR_INJECT_CRASH("crash_change_partition_5") ||
-        alter_close_tables(lpt) ||
+        abort_and_upgrade_lock_and_close_table(lpt) ||
         ERROR_INJECT_CRASH("crash_change_partition_6") ||
         ((!thd->lex->no_write_to_binlog) &&
          (write_bin_log(thd, FALSE,