Bug#54747: Deadlock between REORGANIZE PARTITION and SELECT is not detected

The ALTER PARTITION and SELECT seemed to be deadlocked
when having innodb_thread_concurrency = 1.

Problem was that there was unreleased latches
in the ALTER PARTITION thread which was needed
by the SELECT thread to be able to continue.

Solution was to release the latches by commit 
before requesting upgrade to exclusive MDL lock.

Updated according to reviewers comments (3).

1 files changed, 11 insertions, 10 deletions

diff --git a/sql/sql_partition.cc b/sql/sql_partition.cc
index 5bbe946179e..b72816f8ce3 100644
--- a/sql/sql_partition.cc
+++ b/sql/sql_partition.cc
@@ -63,6 +63,7 @@
 #include "sql_table.h"                  // build_table_filename,
                                         // build_table_shadow_filename,
                                         // table_to_filename
+                                        // mysql_*_alter_copy_data
 #include "opt_range.h"                  // store_key_image_to_rec
 #include "sql_analyse.h"                // append_escaped
 
@@ -4377,7 +4378,6 @@ static int fast_end_partition(THD *thd, ulonglong copied,
                               ALTER_PARTITION_PARAM_TYPE *lpt,
                               bool written_bin_log)
 {
-  int error;
   char tmp_name[80];
   DBUG_ENTER("fast_end_partition");
 
@@ -4386,13 +4386,6 @@ static int fast_end_partition(THD *thd, ulonglong copied,
   if (!is_empty)
     query_cache_invalidate3(thd, table_list, 0);
 
-  error= trans_commit_stmt(thd);
-  if (trans_commit_implicit(thd))
-    error= 1;
-
-  if (error)
-    DBUG_RETURN(TRUE);                      /* The error has been reported */
-
   if ((!is_empty) && (!written_bin_log) &&
       (!thd->lex->no_write_to_binlog) &&
     write_bin_log(thd, FALSE, thd->query(), thd->query_length()))
@@ -5535,17 +5528,25 @@ static bool mysql_change_partitions(ALTER_PARTITION_PARAM_TYPE *lpt)
   char path[FN_REFLEN+1];
   int error;
   handler *file= lpt->table->file;
+  THD *thd= lpt->thd;
   DBUG_ENTER("mysql_change_partitions");
 
   build_table_filename(path, sizeof(path) - 1, lpt->db, lpt->table_name, "", 0);
+
+  if(mysql_trans_prepare_alter_copy_data(thd))
+    DBUG_RETURN(TRUE);
+
   if ((error= file->ha_change_partitions(lpt->create_info, path, &lpt->copied,
                                          &lpt->deleted, lpt->pack_frm_data,
                                          lpt->pack_frm_len)))
   {
     file->print_error(error, MYF(error != ER_OUTOFMEMORY ? 0 : ME_FATALERROR));
-    DBUG_RETURN(TRUE);
   }
-  DBUG_RETURN(FALSE);
+
+  if (mysql_trans_commit_alter_copy_data(thd))
+    DBUG_RETURN(TRUE);                      /* The error has been reported */
+
+  DBUG_RETURN(test(error));
 }