From 6b80cd916a0863f22f68cbbb2572ad67ac877728 Mon Sep 17 00:00:00 2001
From: Magne Mahre <magne.mahre@sun.com>
Date: Thu, 15 Oct 2009 13:07:04 +0200
Subject: [PATCH] Bug #37433  	Deadlock between open_table,
 close_open_tables,                 get_table_share, drop_open_table

In the partition handler code, LOCK_open and share->LOCK_ha_data
are acquired in the wrong order in certain cases.  When doing a
multi-row INSERT (i.e a INSERT..SELECT) in a table with auto-
increment column(s). the increments must be in a monotonically
continuous increasing sequence (i.e it can't have "holes"). To
achieve this, a lock is held for the duration of the operation.
share->LOCK_ha_data was used for this purpose.

Whenever there was a need to open a view _during_ the operation
(views are not currently pre-opened the way tables are), and
LOCK_open was grabbed, a deadlock could occur.  share->LOCK_ha_data
is other places used _while_ holding LOCK_open.

A new mutex was introduced in the HA_DATA_PARTITION structure,
for exclusive use of the autoincrement data fields, so we don't
need to overload the use of LOCK_ha_data here.

A module test case has not been supplied, since the problem occurs
as a result of a race condition, and testing for this condition
is thus not deterministic.   Testing for it could be done by
setting up a test case as described in the bug report.
---
 sql/ha_partition.cc | 17 +++++++++++++++++
 sql/ha_partition.h  |  1 +
 sql/table.cc        |  2 ++
 sql/table.h         |  1 +
 4 files changed, 21 insertions(+)

diff --git a/sql/ha_partition.cc b/sql/ha_partition.cc
index cc041d91809..d04f1b6e7e4 100644
--- a/sql/ha_partition.cc
+++ b/sql/ha_partition.cc
@@ -2452,6 +2452,21 @@ err1:
 /****************************************************************************
                 MODULE open/close object
 ****************************************************************************/
+
+
+/**
+  A destructor for partition-specific TABLE_SHARE data.
+*/
+
+void ha_data_partition_destroy(void *ha_data)
+{
+  if (ha_data)
+  {
+    HA_DATA_PARTITION *ha_data_partition= (HA_DATA_PARTITION*) ha_data;
+    pthread_mutex_destroy(&ha_data_partition->mutex);
+  }
+}
+
 /*
   Open handler object
 
@@ -2608,6 +2623,8 @@ int ha_partition::open(const char *name, int mode, uint test_if_locked)
     }
     DBUG_PRINT("info", ("table_share->ha_data 0x%p", ha_data));
     bzero(ha_data, sizeof(HA_DATA_PARTITION));
+    table_share->ha_data_destroy= ha_data_partition_destroy;
+    pthread_mutex_init(&ha_data->mutex, MY_MUTEX_INIT_FAST);
   }
   if (is_not_tmp_table)
     pthread_mutex_unlock(&table_share->mutex);
diff --git a/sql/ha_partition.h b/sql/ha_partition.h
index ea1ef4d05fc..29509515d23 100644
--- a/sql/ha_partition.h
+++ b/sql/ha_partition.h
@@ -45,6 +45,7 @@ typedef struct st_ha_data_partition
 {
   ulonglong next_auto_inc_val;                 /**< first non reserved value */
   bool auto_inc_initialized;
+  pthread_mutex_t mutex;
 } HA_DATA_PARTITION;
 
 #define PARTITION_BYTES_IN_POS 2
diff --git a/sql/table.cc b/sql/table.cc
index 52e06809d7c..325e84ca55a 100644
--- a/sql/table.cc
+++ b/sql/table.cc
@@ -1601,6 +1601,8 @@ static int open_binary_frm(THD *thd, TABLE_SHARE *share, uchar *head,
   delete crypted;
   delete handler_file;
   my_hash_free(&share->name_hash);
+  if (share->ha_data_destroy)
+    share->ha_data_destroy(share->ha_data);
 
   open_table_error(share, error, share->open_errno, errarg);
   DBUG_RETURN(error);
diff --git a/sql/table.h b/sql/table.h
index d7b6a0d9344..6a626421d3a 100644
--- a/sql/table.h
+++ b/sql/table.h
@@ -419,6 +419,7 @@ struct TABLE_SHARE
 
   /** place to store storage engine specific data */
   void *ha_data;
+  void (*ha_data_destroy)(void *); /* An optional destructor for ha_data */
 
 
   /*