This ChangeSet must be null-merged to 5.1.

Applied innodb-5.0-ss1040 and innodb-5.0-ss1099 snapshots.

Bugs fixed:
- Bug #21468: InnoDB crash during recovery with corrupted data pages: XA bug?
- Bug #24299: Identifiers in foreign keys cannot contain U+0160, U+0360, ..., U+FF60
- Bug #24386: Performance degradation caused by instrumentation in mutex_struct
- Bug #24712: SHOW TABLE STATUS for file-per-table showing incorrect time fields


innobase/dict/dict0dict.c:
  Applied innodb-5.0-ss1040 and innodb-5.0-ss1099 snapshots.
  
  Revision r1030:
  branches/5.0: Replace isspace() with a wrapper ib_isspace(), because on
  Win32 isspace(0xa0) appears to hold.  (Bug #24299)
innobase/include/sync0rw.h:
  Applied innodb-5.0-ss1040 and innodb-5.0-ss1099 snapshots.
  
  Revision r1040:
  branches/5.0: Port r1039 from trunk:
  
  Port r1034 from branches/zip: Remove some instrumentation and reduce
  the output of SHOW MUTEX STATUS in non-debug builds.  (Bug #24386)
innobase/include/sync0sync.h:
  Applied innodb-5.0-ss1040 and innodb-5.0-ss1099 snapshots.
  
  Revision r1040:
  branches/5.0: Port r1039 from trunk:
  
  Port r1034 from branches/zip: Remove some instrumentation and reduce
  the output of SHOW MUTEX STATUS in non-debug builds.  (Bug #24386)
innobase/include/sync0sync.ic:
  Applied innodb-5.0-ss1040 and innodb-5.0-ss1099 snapshots.
  
  Revision r1040:
  branches/5.0: Port r1039 from trunk:
  
  Port r1034 from branches/zip: Remove some instrumentation and reduce
  the output of SHOW MUTEX STATUS in non-debug builds.  (Bug #24386)
innobase/log/log0recv.c:
  Applied innodb-5.0-ss1040 and innodb-5.0-ss1099 snapshots.
  
  Revision r1076:
  branches/5.0: Remove the unintentionally committed change to univ.i in r1075.
  Fix assertion failure sync0sync.c line 1239
  (the latter ut_error in sync_thread_reset_level())
  in crash recovery when UNIV_SYNC_DEBUG is enabled.
  
  
  Revision r1079:
  branches/5.0: recv_recovery_from_checkpoint_finish(): Add 1 sec delay
  before switching on the sync order checks in crash recovery, so that
  file I/O threads have time to suspend themselves.
innobase/srv/srv0start.c:
  Applied innodb-5.0-ss1040 and innodb-5.0-ss1099 snapshots.
  
  Revision r1075:
  branches/5.0: Fix assertion failure sync0sync.c line 1239
  (the latter ut_error in sync_thread_reset_level())
  in crash recovery when UNIV_SYNC_DEBUG is enabled.
  
  
  Revision r1077:
  branches/5.0: innobase_start_or_create_for_mysql(): Remove unnecessary delay
  now that we moved the setting sync_order_checks_on=TRUE to log0recv.c,
  to the start of the rollback phase in crash recovery.
innobase/sync/sync0rw.c:
  Applied innodb-5.0-ss1040 and innodb-5.0-ss1099 snapshots.
  
  Revision r1040:
  branches/5.0: Port r1039 from trunk:
  
  Port r1034 from branches/zip: Remove some instrumentation and reduce
  the output of SHOW MUTEX STATUS in non-debug builds.  (Bug #24386)
innobase/sync/sync0sync.c:
  Applied innodb-5.0-ss1040 and innodb-5.0-ss1099 snapshots.
  
  Revision r1040:
  branches/5.0: Port r1039 from trunk:
  
  Port r1034 from branches/zip: Remove some instrumentation and reduce
  the output of SHOW MUTEX STATUS in non-debug builds.  (Bug #24386)
innobase/trx/trx0roll.c:
  Applied innodb-5.0-ss1040 and innodb-5.0-ss1099 snapshots.
  
  Revision r1067:
  branches/5.0: trx_rollback_for_mysql(), trx_commit_for_mysql():
  Protect the creation of trx_dummy_sess with kernel_mutex.
  This error was introduced in r1046 and r1050.
  
  
  Revision r1050:
  branches/5.0: trx_rollback_for_mysql(): Fix the comment introduced in r1046.
  
  trx_commit_for_mysql(): Use the dummy trx->sess also for committing a prepared
  transaction in XA recovery, just in case our code would need the session
  object also in that case (does not seem to need it right now).
  
  
  Revision r1048:
  branches/5.0: trx_rollback_for_mysql(): Do not set trx->sess back to NULL.
  This bug was introduced in r1046.
  
  
  Revision r1046:
  branches/5.0: trx_rollback_for_mysql(): Ensure that trx->sess is non-NULL
  when calling trx_general_rollback_for_mysql().  This removes a segmentation
  fault when rolling back a prepared transaction in XA recovery.  (Bug #21468)
innobase/trx/trx0trx.c:
  Applied innodb-5.0-ss1040 and innodb-5.0-ss1099 snapshots.
  
  Revision r1067:
  branches/5.0: trx_rollback_for_mysql(), trx_commit_for_mysql():
  Protect the creation of trx_dummy_sess with kernel_mutex.
  This error was introduced in r1046 and r1050.
  
  
  Revision r1050:
  branches/5.0: trx_rollback_for_mysql(): Fix the comment introduced in r1046.
  
  trx_commit_for_mysql(): Use the dummy trx->sess also for committing a prepared
  transaction in XA recovery, just in case our code would need the session
  object also in that case (does not seem to need it right now).
sql/ha_innodb.cc:
  Applied innodb-5.0-ss1040 and innodb-5.0-ss1099 snapshots.
  
  Revision r1040:
  branches/5.0: Port r1039 from trunk:
  
  Port r1034 from branches/zip: Remove some instrumentation and reduce
  the output of SHOW MUTEX STATUS in non-debug builds.  (Bug #24386)
  
  
  Revision r1099:
  branches/5.0: Merge revision 1098 from trunk: Fix bug #24712: SHOW TABLE
  STATUS for file-per-table showing incorrect time fields

10 files changed, 122 insertions, 62 deletions

diff --git a/innobase/dict/dict0dict.c b/innobase/dict/dict0dict.c
index fffe851bc52..ba03e1f5e41 100644
--- a/innobase/dict/dict0dict.c
+++ b/innobase/dict/dict0dict.c
@@ -27,6 +27,9 @@ Created 1/8/1996 Heikki Tuuri
 #include "que0que.h"
 #include "rem0cmp.h"
 
+/* Implement isspace() in a locale-independent way. (Bug #24299) */
+#define ib_isspace(c) strchr(" \v\f\t\r\n", c)
+
 dict_sys_t*	dict_sys	= NULL;	/* the dictionary system */
 
 rw_lock_t	dict_operation_lock;	/* table create, drop, etc. reserve
@@ -2406,7 +2409,7 @@ dict_accept(
 
 	*success = FALSE;
 	
-	while (isspace(*ptr)) {
+	while (ib_isspace(*ptr)) {
 		ptr++;
 	}
 
@@ -2451,7 +2454,7 @@ dict_scan_id(
 
 	*id = NULL;
 
-	while (isspace(*ptr)) {
+	while (ib_isspace(*ptr)) {
 		ptr++;
 	}
 
@@ -2482,7 +2485,7 @@ dict_scan_id(
 			len++;
 		}
 	} else {
-		while (!isspace(*ptr) && *ptr != '(' && *ptr != ')'
+		while (!ib_isspace(*ptr) && *ptr != '(' && *ptr != ')'
 		       && (accept_also_dot || *ptr != '.')
 		       && *ptr != ',' && *ptr != '\0') {
 
@@ -2512,12 +2515,12 @@ dict_scan_id(
 	if (heap && !quote) {
 		/* EMS MySQL Manager sometimes adds characters 0xA0 (in
 		latin1, a 'non-breakable space') to the end of a table name.
-		But isspace(0xA0) is not true, which confuses our foreign key
-		parser. After the UTF-8 conversion in ha_innodb.cc, bytes 0xC2
-		and 0xA0 are at the end of the string.
+		After the UTF-8 conversion in ha_innodb.cc, bytes 0xC2
+		and 0xA0 are at the end of the string, and ib_isspace()
+		does not work for multi-byte UTF-8 characters.
 
-		TODO: we should lex the string using thd->charset_info, and
-		my_isspace(). Only after that, convert id names to UTF-8. */
+		In MySQL 5.1 we lex the string using thd->charset_info, and
+		my_isspace(). This workaround is not needed there. */
 
 		b = (byte*)(*id);
 		id_len = strlen((char*) b);
@@ -3006,11 +3009,11 @@ loop:
 
 		ut_a(success);
 
-		if (!isspace(*ptr) && *ptr != '"' && *ptr != '`') {
+		if (!ib_isspace(*ptr) && *ptr != '"' && *ptr != '`') {
 	        	goto loop;
 		}
 
-		while (isspace(*ptr)) {
+		while (ib_isspace(*ptr)) {
 			ptr++;
 		}
 
@@ -3052,7 +3055,7 @@ loop:
 		goto loop;
 	}
 
-	if (!isspace(*ptr)) {
+	if (!ib_isspace(*ptr)) {
 	        goto loop;
 	}
 
@@ -3140,7 +3143,7 @@ col_loop1:
 	}
 	ptr = dict_accept(ptr, "REFERENCES", &success);
 
-	if (!success || !isspace(*ptr)) {
+	if (!success || !ib_isspace(*ptr)) {
 		dict_foreign_report_syntax_err(name, start_of_latest_foreign,
 									ptr);
 		return(DB_CANNOT_ADD_CONSTRAINT);
@@ -3527,7 +3530,7 @@ loop:
 
 	ptr = dict_accept(ptr, "DROP", &success);
 
-	if (!isspace(*ptr)) {
+	if (!ib_isspace(*ptr)) {
 
 	        goto loop;
 	}
diff --git a/innobase/include/sync0rw.h b/innobase/include/sync0rw.h
index 741f9500612..4cd26ba1921 100644
--- a/innobase/include/sync0rw.h
+++ b/innobase/include/sync0rw.h
@@ -61,8 +61,12 @@ Creates, or rather, initializes an rw-lock object in a specified memory
 location (which must be appropriately aligned). The rw-lock is initialized
 to the non-locked state. Explicit freeing of the rw-lock with rw_lock_free
 is necessary only if the memory block containing it is freed. */
-#define rw_lock_create(L) rw_lock_create_func((L), __FILE__, __LINE__, #L)
-          
+#ifdef UNIV_DEBUG
+# define rw_lock_create(L) rw_lock_create_func((L), #L, __FILE__, __LINE__)
+#else /* UNIV_DEBUG */
+# define rw_lock_create(L) rw_lock_create_func((L), __FILE__, __LINE__)
+#endif /* UNIV_DEBUG */
+
 /*=====================*/
 /**********************************************************************
 Creates, or rather, initializes an rw-lock object in a specified memory
@@ -74,9 +78,11 @@ void
 rw_lock_create_func(
 /*================*/
 	rw_lock_t*	lock,		/* in: pointer to memory */
+#ifdef UNIV_DEBUG
+	const char*	cmutex_name, 	/* in: mutex name */
+#endif /* UNIV_DEBUG */
 	const char*	cfile_name,	/* in: file name where created */
-  ulint cline,  /* in: file line where created */
-  const char* cmutex_name); /* in: mutex name */
+	ulint		cline);		/* in: file line where created */
 /**********************************************************************
 Calling this function is obligatory only if the memory buffer containing
 the rw-lock is freed. Removes an rw-lock object from the global list. The
diff --git a/innobase/include/sync0sync.h b/innobase/include/sync0sync.h
index 9893921c5d2..769c2a98244 100644
--- a/innobase/include/sync0sync.h
+++ b/innobase/include/sync0sync.h
@@ -39,7 +39,11 @@ location (which must be appropriately aligned). The mutex is initialized
 in the reset state. Explicit freeing of the mutex with mutex_free is
 necessary only if the memory block containing it is freed. */
 
-#define mutex_create(M)	mutex_create_func((M), __FILE__, __LINE__, #M)
+#ifdef UNIV_DEBUG
+# define mutex_create(M) mutex_create_func((M), #M, __FILE__, __LINE__)
+#else
+# define mutex_create(M) mutex_create_func((M), __FILE__, __LINE__)
+#endif
 /*===================*/
 /**********************************************************************
 Creates, or rather, initializes a mutex object in a specified memory
@@ -51,9 +55,11 @@ void
 mutex_create_func(
 /*==============*/
 	mutex_t*	mutex,		/* in: pointer to memory */
+#ifdef UNIV_DEBUG
+	const char*	cmutex_name,	/* in: mutex name */
+#endif /* UNIV_DEBUG */
 	const char*	cfile_name,	/* in: file name where created */
-  ulint cline,  /* in: file line where created */
-  const char* cmutex_name); /* in: mutex name */
+	ulint		cline);		/* in: file line where created */
 /**********************************************************************
 Calling this function is obligatory only if the memory buffer containing
 the mutex is freed. Removes a mutex object from the mutex list. The mutex
@@ -479,15 +485,17 @@ struct mutex_struct {
 	ulint	cline;		/* Line where created */
 	ulint	magic_n;
 #ifndef UNIV_HOTBACKUP
-  ulong count_using; /* count of times mutex used */
-  ulong count_spin_loop; /* count of spin loops */
-  ulong count_spin_rounds; /* count of spin rounds */
-  ulong count_os_wait; /* count of os_wait */
-  ulong count_os_yield; /* count of os_wait */
-  ulonglong lspent_time; /* mutex os_wait timer msec */
-  ulonglong lmax_spent_time; /* mutex os_wait timer msec */
-  const char* cmutex_name;/* mutex name  */
-  ulint mutex_type;/* 0 - usual mutex 1 - rw_lock mutex  */
+	ulong		count_os_wait; /* count of os_wait */
+# ifdef UNIV_DEBUG
+	ulong		count_using; /* count of times mutex used */
+	ulong		count_spin_loop; /* count of spin loops */
+	ulong		count_spin_rounds; /* count of spin rounds */
+	ulong		count_os_yield; /* count of os_wait */
+	ulonglong	lspent_time; /* mutex os_wait timer msec */
+	ulonglong	lmax_spent_time; /* mutex os_wait timer msec */
+	const char*	cmutex_name;/* mutex name */
+	ulint		mutex_type;/* 0 - usual mutex 1 - rw_lock mutex	 */
+# endif /* UNIV_DEBUG */
 #endif /* !UNIV_HOTBACKUP */
 };
 
diff --git a/innobase/include/sync0sync.ic b/innobase/include/sync0sync.ic
index b3fde61db5e..a32a82d6e8b 100644
--- a/innobase/include/sync0sync.ic
+++ b/innobase/include/sync0sync.ic
@@ -250,9 +250,9 @@ mutex_enter_func(
 	/* Note that we do not peek at the value of lock_word before trying
 	the atomic test_and_set; we could peek, and possibly save time. */
 
-#ifndef UNIV_HOTBACKUP
+#if defined UNIV_DEBUG && !defined UNIV_HOTBACKUP
   mutex->count_using++;
-#endif /* UNIV_HOTBACKUP */
+#endif /* UNIV_DEBUG && !UNIV_HOTBACKUP */
 	
   if (!mutex_test_and_set(mutex))
   {
diff --git a/innobase/log/log0recv.c b/innobase/log/log0recv.c
index 113d237b535..c1ceb9791f2 100644
--- a/innobase/log/log0recv.c
+++ b/innobase/log/log0recv.c
@@ -33,6 +33,7 @@ Created 9/20/1997 Heikki Tuuri
 #include "btr0cur.h"
 #include "dict0boot.h"
 #include "fil0fil.h"
+#include "sync0sync.h"
 
 #ifdef UNIV_HOTBACKUP
 /* This is set to FALSE if the backup was originally taken with the
@@ -2969,6 +2970,15 @@ recv_recovery_from_checkpoint_finish(void)
 #ifndef UNIV_LOG_DEBUG
 	recv_sys_free();
 #endif
+
+#ifdef UNIV_SYNC_DEBUG
+	/* Wait for a while so that created threads have time to suspend
+	themselves before we switch the latching order checks on */
+	os_thread_sleep(1000000);
+
+	/* Switch latching order checks on in sync0sync.c */
+	sync_order_checks_on = TRUE;
+#endif
 	if (srv_force_recovery < SRV_FORCE_NO_TRX_UNDO) {
 		/* Rollback the uncommitted transactions which have no user
 		session */
diff --git a/innobase/srv/srv0start.c b/innobase/srv/srv0start.c
index b41dcbe44cd..5f8707a661c 100644
--- a/innobase/srv/srv0start.c
+++ b/innobase/srv/srv0start.c
@@ -1554,17 +1554,6 @@ innobase_start_or_create_for_mysql(void)
 	srv_was_started = TRUE;
 	srv_is_being_started = FALSE;
 
-#ifdef UNIV_DEBUG
-        /* Wait a while so that the created threads have time to suspend
-	themselves before we switch sync debugging on; otherwise a thread may
-	execute mutex_enter() before the checks are on, and mutex_exit() after
-	the checks are on, which will cause an assertion failure in sync
-	debug. */
-
-        os_thread_sleep(3000000);
-#endif
-	sync_order_checks_on = TRUE;
-
         if (trx_doublewrite == NULL) {
 		/* Create the doublewrite buffer to a new tablespace */
 
diff --git a/innobase/sync/sync0rw.c b/innobase/sync/sync0rw.c
index 050de73db9e..629331d6049 100644
--- a/innobase/sync/sync0rw.c
+++ b/innobase/sync/sync0rw.c
@@ -89,9 +89,11 @@ void
 rw_lock_create_func(
 /*================*/
 	rw_lock_t*	lock,		/* in: pointer to memory */
+#ifdef UNIV_DEBUG
+	const char*	cmutex_name, 	/* in: mutex name */
+#endif /* UNIV_DEBUG */
 	const char*	cfile_name,	/* in: file name where created */
-  ulint cline,  /* in: file line where created */
-  const char* cmutex_name)  /* in: mutex name */
+	ulint		cline)		/* in: file line where created */
 {
 	/* If this is the very first time a synchronization
 	object is created, then the following call initializes
@@ -102,10 +104,10 @@ rw_lock_create_func(
 
 	lock->mutex.cfile_name = cfile_name;
 	lock->mutex.cline = cline;
-#ifndef UNIV_HOTBACKUP
-  lock->mutex.cmutex_name = cmutex_name;
-  lock->mutex.mutex_type = 1;
-#endif /* !UNIV_HOTBACKUP */
+#if defined UNIV_DEBUG && !defined UNIV_HOTBACKUP
+	lock->mutex.cmutex_name = cmutex_name;
+	lock->mutex.mutex_type = 1;
+#endif /* UNIV_DEBUG && !UNIV_HOTBACKUP */
   
 	rw_lock_set_waiters(lock, 0);
 	rw_lock_set_writer(lock, RW_LOCK_NOT_LOCKED);
diff --git a/innobase/sync/sync0sync.c b/innobase/sync/sync0sync.c
index 95bf83dce79..25b7a5588d9 100644
--- a/innobase/sync/sync0sync.c
+++ b/innobase/sync/sync0sync.c
@@ -202,9 +202,11 @@ void
 mutex_create_func(
 /*==============*/
 	mutex_t*	mutex,		/* in: pointer to memory */
+#ifdef UNIV_DEBUG
+	const char*	cmutex_name,	/* in: mutex name */
+#endif /* UNIV_DEBUG */
 	const char*	cfile_name,	/* in: file name where created */
-  ulint cline,  /* in: file line where created */
-  const char* cmutex_name)  /* in: mutex name */
+	ulint		cline)		/* in: file line where created */
 {
 #if defined(_WIN32) && defined(UNIV_CAN_USE_X86_ASSEMBLER)
 	mutex_reset_lock_word(mutex);
@@ -223,6 +225,8 @@ mutex_create_func(
 	mutex->cfile_name = cfile_name;
 	mutex->cline = cline;
 #ifndef UNIV_HOTBACKUP
+	mutex->count_os_wait = 0;
+# ifdef UNIV_DEBUG
   mutex->cmutex_name=     cmutex_name;
   mutex->count_using=     0;
   mutex->mutex_type=      0;
@@ -230,8 +234,8 @@ mutex_create_func(
   mutex->lmax_spent_time=     0;
   mutex->count_spin_loop= 0;
   mutex->count_spin_rounds=   0; 
-  mutex->count_os_wait=   0;
   mutex->count_os_yield=  0;
+# endif /* UNIV_DEBUG */
 #endif /* !UNIV_HOTBACKUP */
 	
 	/* Check that lock_word is aligned; this is important on Intel */
@@ -378,13 +382,13 @@ mutex_spin_wait(
 {
   ulint    index; /* index of the reserved wait cell */
   ulint    i;     /* spin round count */
-#ifndef UNIV_HOTBACKUP
+#if defined UNIV_DEBUG && !defined UNIV_HOTBACKUP
   ib_longlong lstart_time = 0, lfinish_time; /* for timing os_wait */
   ulint ltime_diff;
   ulint sec;
   ulint ms;
   uint timer_started = 0;
-#endif /* !UNIV_HOTBACKUP */
+#endif /* UNIV_DEBUG && !UNIV_HOTBACKUP */
   ut_ad(mutex);
 
 mutex_loop:
@@ -398,10 +402,10 @@ mutex_loop:
   memory word. */
 
 spin_loop:
-#ifndef UNIV_HOTBACKUP
+#if defined UNIV_DEBUG && !defined UNIV_HOTBACKUP
   mutex_spin_wait_count++;
   mutex->count_spin_loop++;
-#endif /* !UNIV_HOTBACKUP */
+#endif /* UNIV_DEBUG && !UNIV_HOTBACKUP */
 
   while (mutex_get_lock_word(mutex) != 0 && i < SYNC_SPIN_ROUNDS)
   {
@@ -415,7 +419,7 @@ spin_loop:
 
   if (i == SYNC_SPIN_ROUNDS)
   {
-#ifndef UNIV_HOTBACKUP
+#if defined UNIV_DEBUG && !defined UNIV_HOTBACKUP
     mutex->count_os_yield++;
     if (timed_mutexes == 1 && timer_started==0)
     {
@@ -423,7 +427,7 @@ spin_loop:
       lstart_time= (ib_longlong)sec * 1000000 + ms;
       timer_started = 1;
     }
-#endif /* !UNIV_HOTBACKUP */
+#endif /* UNIV_DEBUG && !UNIV_HOTBACKUP */
     os_thread_yield();
   }
 
@@ -436,9 +440,9 @@ spin_loop:
 
   mutex_spin_round_count += i;
 
-#ifndef UNIV_HOTBACKUP
+#if defined UNIV_DEBUG && !defined UNIV_HOTBACKUP
   mutex->count_spin_rounds += i;
-#endif /* !UNIV_HOTBACKUP */
+#endif /* UNIV_DEBUG && !UNIV_HOTBACKUP */
 
   if (mutex_test_and_set(mutex) == 0)
   {
@@ -522,6 +526,7 @@ Now there is no risk of infinite wait on the event. */
 
 #ifndef UNIV_HOTBACKUP
   mutex->count_os_wait++;
+# ifdef UNIV_DEBUG
   /*
     !!!!! Sometimes os_wait can be called without  os_thread_yield
   */
@@ -532,13 +537,14 @@ Now there is no risk of infinite wait on the event. */
     lstart_time= (ib_longlong)sec * 1000000 + ms;
     timer_started = 1;
   }
+# endif /* UNIV_DEBUG */
 #endif /* !UNIV_HOTBACKUP */
 
   sync_array_wait_event(sync_primary_wait_array, index);
   goto mutex_loop;  
 
 finish_timing:
-#ifndef UNIV_HOTBACKUP
+#if defined UNIV_DEBUG && !defined UNIV_HOTBACKUP
   if (timed_mutexes == 1 && timer_started==1)
   {
     ut_usectime(&sec, &ms);
@@ -551,7 +557,7 @@ finish_timing:
       mutex->lmax_spent_time= ltime_diff;
     }
   }
-#endif /* !UNIV_HOTBACKUP */
+#endif /* UNIV_DEBUG && !UNIV_HOTBACKUP */
   return;
 }
 
diff --git a/innobase/trx/trx0roll.c b/innobase/trx/trx0roll.c
index fdfb7428129..bf8b9fd1939 100644
--- a/innobase/trx/trx0roll.c
+++ b/innobase/trx/trx0roll.c
@@ -129,9 +129,27 @@ trx_rollback_for_mysql(
 	}
 
 	trx->op_info = "rollback";
+
+	/* If we are doing the XA recovery of prepared transactions, then
+	the transaction object does not have an InnoDB session object, and we
+	set a dummy session that we use for all MySQL transactions. */
 	
-	err = trx_general_rollback_for_mysql(trx, FALSE, NULL);
+	mutex_enter(&kernel_mutex);
+
+	if (trx->sess == NULL) {
+		/* Open a dummy session */
+
+		if (!trx_dummy_sess) {
+			trx_dummy_sess = sess_open();
+		}
 
+		trx->sess = trx_dummy_sess;
+	}
+
+	mutex_exit(&kernel_mutex);
+
+	err = trx_general_rollback_for_mysql(trx, FALSE, NULL);
+	
 	trx->op_info = "";
 
 	return(err);
diff --git a/innobase/trx/trx0trx.c b/innobase/trx/trx0trx.c
index 2637b28ef90..4dc826e5947 100644
--- a/innobase/trx/trx0trx.c
+++ b/innobase/trx/trx0trx.c
@@ -1601,7 +1601,25 @@ trx_commit_for_mysql(
 	ut_a(trx);
 
 	trx->op_info = "committing";
+
+	/* If we are doing the XA recovery of prepared transactions, then
+	the transaction object does not have an InnoDB session object, and we
+	set the dummy session that we use for all MySQL transactions. */
+	
+	mutex_enter(&kernel_mutex);
+
+	if (trx->sess == NULL) {
+		/* Open a dummy session */
+
+		if (!trx_dummy_sess) {
+			trx_dummy_sess = sess_open();
+		}
+
+		trx->sess = trx_dummy_sess;
+	}
 	
+	mutex_exit(&kernel_mutex);
+
 	trx_start_if_not_started(trx);
 
 	mutex_enter(&kernel_mutex);