Automatic merge

include/violite.h

@@ -216,7 +216,7 @@ struct st_vio
   struct sockaddr_storage	remote;		/* Remote internet address */
   int addrLen;                          /* Length of remote address */
   enum enum_vio_type	type;		/* Type of connection */
-  char			desc[30];	/* String description */
+  const char		*desc;		/* String description */
   char                  *read_buffer;   /* buffer for vio_read_buff */
   char                  *read_pos;      /* start of unfetched data in the
                                            read buffer */

mysql-test/suite/perfschema/r/all_instances.result

@@ -64,6 +64,7 @@ wait/synch/mutex/sql/LOCK_server_started
 wait/synch/mutex/sql/LOCK_slave_list
 wait/synch/mutex/sql/LOCK_stats
 wait/synch/mutex/sql/LOCK_status
+wait/synch/mutex/sql/LOCK_thread_cache
 wait/synch/mutex/sql/LOCK_thread_count
 wait/synch/mutex/sql/LOCK_user_conn
 wait/synch/mutex/sql/LOCK_user_locks

mysql-test/suite/perfschema/r/func_mutex.result

@@ -70,52 +70,34 @@ Success
 TRUNCATE TABLE performance_schema.events_waits_history_long;
 TRUNCATE TABLE performance_schema.events_waits_history;
 TRUNCATE TABLE performance_schema.events_waits_current;
-SELECT * FROM t1 WHERE id = 1;
-id	b
-1	initial value
+show variables like "%not_found%";
+Variable_name	Value
 SET @before_count = (SELECT SUM(TIMER_WAIT)
 FROM performance_schema.events_waits_history_long
-WHERE (EVENT_NAME = 'wait/synch/rwlock/sql/LOCK_grant'));
-SELECT * FROM t1;
-id	b
-1	initial value
-2	initial value
-3	initial value
-4	initial value
-5	initial value
-6	initial value
-7	initial value
-8	initial value
+WHERE (EVENT_NAME = 'wait/synch/rwlock/sql/LOCK_system_variables_hash'));
+show variables like "%not_found%";
+Variable_name	Value
 SET @after_count = (SELECT SUM(TIMER_WAIT)
 FROM performance_schema.events_waits_history_long
-WHERE (EVENT_NAME = 'wait/synch/rwlock/sql/LOCK_grant'));
+WHERE (EVENT_NAME = 'wait/synch/rwlock/sql/LOCK_system_variables_hash'));
 SELECT IF((@after_count - @before_count) > 0, 'Success', 'Failure') test_fm1_rw_timed;
 test_fm1_rw_timed
 Success
 UPDATE performance_schema.setup_instruments SET enabled = 'NO'
-WHERE NAME = 'wait/synch/rwlock/sql/LOCK_grant';
+WHERE NAME = 'wait/synch/rwlock/sql/LOCK_system_variables_hash';
 TRUNCATE TABLE performance_schema.events_waits_history_long;
 TRUNCATE TABLE performance_schema.events_waits_history;
 TRUNCATE TABLE performance_schema.events_waits_current;
-SELECT * FROM t1 WHERE id = 1;
-id	b
-1	initial value
+show variables like "%not_found%";
+Variable_name	Value
 SET @before_count = (SELECT SUM(TIMER_WAIT)
 FROM performance_schema.events_waits_history_long
-WHERE (EVENT_NAME = 'wait/synch/rwlock/sql/LOCK_grant'));
-SELECT * FROM t1;
-id	b
-1	initial value
-2	initial value
-3	initial value
-4	initial value
-5	initial value
-6	initial value
-7	initial value
-8	initial value
+WHERE (EVENT_NAME = 'wait/synch/rwlock/sql/LOCK_system_variables_hash'));
+show variables like "%not_found%";
+Variable_name	Value
 SET @after_count = (SELECT SUM(TIMER_WAIT)
 FROM performance_schema.events_waits_history_long
-WHERE (EVENT_NAME = 'wait/synch/rwlock/sql/LOCK_grant'));
+WHERE (EVENT_NAME = 'LOCK_system_variables_hash'));
 SELECT IF((COALESCE(@after_count, 0) - COALESCE(@before_count, 0)) = 0, 'Success', 'Failure') test_fm2_rw_timed;
 test_fm2_rw_timed
 Success

mysql-test/suite/perfschema/t/func_mutex.test

@@ -87,38 +87,38 @@ TRUNCATE TABLE performance_schema.events_waits_history_long;
 TRUNCATE TABLE performance_schema.events_waits_history;
 TRUNCATE TABLE performance_schema.events_waits_current;
 
-SELECT * FROM t1 WHERE id = 1;
+show variables like "%not_found%";
 
 SET @before_count = (SELECT SUM(TIMER_WAIT)
                      FROM performance_schema.events_waits_history_long
-                     WHERE (EVENT_NAME = 'wait/synch/rwlock/sql/LOCK_grant'));
+                     WHERE (EVENT_NAME = 'wait/synch/rwlock/sql/LOCK_system_variables_hash'));
 
-SELECT * FROM t1;
+show variables like "%not_found%";
 
 SET @after_count = (SELECT SUM(TIMER_WAIT)
                     FROM performance_schema.events_waits_history_long
-                    WHERE (EVENT_NAME = 'wait/synch/rwlock/sql/LOCK_grant'));
+                    WHERE (EVENT_NAME = 'wait/synch/rwlock/sql/LOCK_system_variables_hash'));
 
 SELECT IF((@after_count - @before_count) > 0, 'Success', 'Failure') test_fm1_rw_timed;
 
 UPDATE performance_schema.setup_instruments SET enabled = 'NO'
-WHERE NAME = 'wait/synch/rwlock/sql/LOCK_grant';
+WHERE NAME = 'wait/synch/rwlock/sql/LOCK_system_variables_hash';
 
 TRUNCATE TABLE performance_schema.events_waits_history_long;
 TRUNCATE TABLE performance_schema.events_waits_history;
 TRUNCATE TABLE performance_schema.events_waits_current;
 
-SELECT * FROM t1 WHERE id = 1;
+show variables like "%not_found%";
 
 SET @before_count = (SELECT SUM(TIMER_WAIT)
                      FROM performance_schema.events_waits_history_long
-                     WHERE (EVENT_NAME = 'wait/synch/rwlock/sql/LOCK_grant'));
+                     WHERE (EVENT_NAME = 'wait/synch/rwlock/sql/LOCK_system_variables_hash'));
 
-SELECT * FROM t1;
+show variables like "%not_found%";
 
 SET @after_count = (SELECT SUM(TIMER_WAIT)
                     FROM performance_schema.events_waits_history_long
-                    WHERE (EVENT_NAME = 'wait/synch/rwlock/sql/LOCK_grant'));
+                    WHERE (EVENT_NAME = 'LOCK_system_variables_hash'));
 
 SELECT IF((COALESCE(@after_count, 0) - COALESCE(@before_count, 0)) = 0, 'Success', 'Failure') test_fm2_rw_timed;
 

mysys/my_gethwaddr.c

@@ -87,13 +87,17 @@ my_bool my_gethwaddr(uchar *to)
   int fd, res= 1;
   struct ifreq ifr[32];
   struct ifconf ifc;
+  DBUG_ENTER("my_gethwaddr");
 
   ifc.ifc_req= ifr;
   ifc.ifc_len= sizeof(ifr);
 
   fd = socket(AF_INET, SOCK_DGRAM, 0);
   if (fd < 0)
+  {
+    DBUG_PRINT("error", ("socket() call failed with %d", errno));
     goto err;
+  }
 
   if (ioctl(fd, SIOCGIFCONF, (char*)&ifc) >= 0)
   {
@@ -106,8 +110,8 @@ my_bool my_gethwaddr(uchar *to)
                              ETHER_ADDR_LEN);
 #else
       /*
-        A bug in OpenSolaris used to prevent non-root from getting a mac address:
-        {no url. Oracle killed the old OpenSolaris bug database}
+        A bug in OpenSolaris used to prevent non-root from getting a mac
+        address: {no url. Oracle killed the old OpenSolaris bug database}
 
         Thus, we'll use an alternative method and extract the address from the
         arp table.
@@ -124,7 +128,7 @@ my_bool my_gethwaddr(uchar *to)
 
   close(fd);
 err:
-  return res;
+  DBUG_RETURN(res);
 }
 
 #elif defined(_WIN32)

mysys/my_rnd.c

@@ -45,11 +45,20 @@ void my_rnd_init(struct my_rnd_struct *rand_st, ulong seed1, ulong seed2)
     
   RETURN VALUE
     generated pseudo random number
+
+  NOTE:
+    This is codes so that it can be called by two threads at the same time
+    with minimum impact.
+    (As the number is supposed to be random, it doesn't matter much if
+    rand->seed1 or rand->seed2 are updated with slightly wrong numbers or
+    if two threads gets the same number.
 */
 
 double my_rnd(struct my_rnd_struct *rand_st)
 {
-  rand_st->seed1=(rand_st->seed1*3+rand_st->seed2) % rand_st->max_value;
-  rand_st->seed2=(rand_st->seed1+rand_st->seed2+33) % rand_st->max_value;
-  return (((double) rand_st->seed1)/rand_st->max_value_dbl);
+  unsigned long seed1;
+  seed1= (rand_st->seed1*3+rand_st->seed2) % rand_st->max_value;
+  rand_st->seed2=(seed1+rand_st->seed2+33) % rand_st->max_value;
+  rand_st->seed1= seed1;
+  return (((double) seed1)/rand_st->max_value_dbl);
 }

sql/event_scheduler.cc

@@ -132,11 +132,11 @@ post_init_event_thread(THD *thd)
     return TRUE;
   }
 
+  thread_safe_increment32(&thread_count, &thread_count_lock);
   mysql_mutex_lock(&LOCK_thread_count);
   threads.append(thd);
-  thread_count++;
-  inc_thread_running();
   mysql_mutex_unlock(&LOCK_thread_count);
+  inc_thread_running();
   return FALSE;
 }
 
@@ -154,12 +154,8 @@ deinit_event_thread(THD *thd)
 {
   thd->proc_info= "Clearing";
   DBUG_PRINT("exit", ("Event thread finishing"));
-  mysql_mutex_lock(&LOCK_thread_count);
-  thread_count--;
-  dec_thread_running();
-  delete thd;
-  mysql_cond_broadcast(&COND_thread_count);
-  mysql_mutex_unlock(&LOCK_thread_count);
+
+  delete_running_thd(thd);
 }
 
 
@@ -436,12 +432,7 @@ Event_scheduler::start()
     ret= TRUE;
 
     new_thd->proc_info= "Clearing";
-    mysql_mutex_lock(&LOCK_thread_count);
-    thread_count--;
-    dec_thread_running();
-    delete new_thd;
-    mysql_cond_broadcast(&COND_thread_count);
-    mysql_mutex_unlock(&LOCK_thread_count);
+    delete_running_thd(new_thd);
   }
 end:
   UNLOCK_DATA();
@@ -570,12 +561,7 @@ error:
   if (new_thd)
   {
     new_thd->proc_info= "Clearing";
-    mysql_mutex_lock(&LOCK_thread_count);
-    thread_count--;
-    dec_thread_running();
-    delete new_thd;
-    mysql_cond_broadcast(&COND_thread_count);
-    mysql_mutex_unlock(&LOCK_thread_count);
+    delete_running_thd(new_thd);
   }
   delete event_name;
   DBUG_RETURN(TRUE);

sql/mysqld.h

@@ -56,6 +56,7 @@ void kill_mysql(void);
 void close_connection(THD *thd, uint sql_errno= 0);
 void handle_connection_in_main_thread(THD *thd);
 void create_thread_to_handle_connection(THD *thd);
+void delete_running_thd(THD *thd);
 void unlink_thd(THD *thd);
 bool one_thread_per_connection_end(THD *thd, bool put_in_cache);
 void flush_thread_cache();
@@ -89,7 +90,6 @@ extern bool opt_ignore_builtin_innodb;
 extern my_bool opt_character_set_client_handshake;
 extern bool volatile abort_loop;
 extern bool in_bootstrap;
-extern uint volatile thread_count;
 extern uint connection_count;
 extern my_bool opt_safe_user_create;
 extern my_bool opt_safe_show_db, opt_local_infile, opt_myisam_use_mmap;
@@ -352,7 +352,8 @@ extern mysql_rwlock_t LOCK_system_variables_hash;
 extern mysql_cond_t COND_thread_count;
 extern mysql_cond_t COND_manager;
 extern int32 thread_running;
-extern my_atomic_rwlock_t thread_running_lock;
+extern int32 thread_count;
+extern my_atomic_rwlock_t thread_running_lock, thread_count_lock;
 
 extern char *opt_ssl_ca, *opt_ssl_capath, *opt_ssl_cert, *opt_ssl_cipher,
             *opt_ssl_key;
@@ -449,7 +450,7 @@ inline query_id_t next_query_id()
   my_atomic_rwlock_wrlock(&global_query_id_lock);
   id= my_atomic_add64(&global_query_id, 1);
   my_atomic_rwlock_wrunlock(&global_query_id_lock);
-  return (id+1);
+  return (id);
 }
 
 inline query_id_t get_query_id()
@@ -479,42 +480,30 @@ inline void table_case_convert(char * name, uint length)
                                      name, length, name, length);
 }
 
-inline ulong sql_rnd_with_mutex()
+inline void thread_safe_increment32(int32 *value, my_atomic_rwlock_t *lock)
 {
-  mysql_mutex_lock(&LOCK_thread_count);
-  ulong tmp=(ulong) (my_rnd(&sql_rand) * 0xffffffff); /* make all bits random */
-  mysql_mutex_unlock(&LOCK_thread_count);
-  return tmp;
+  my_atomic_rwlock_wrlock(lock);
+  (void) my_atomic_add32(value, 1);
+  my_atomic_rwlock_wrunlock(lock);
 }
 
-inline int32
-inc_thread_running()
+inline void thread_safe_decrement32(int32 *value, my_atomic_rwlock_t *lock)
 {
-  int32 num_thread_running;
-  my_atomic_rwlock_wrlock(&thread_running_lock);
-  num_thread_running= my_atomic_add32(&thread_running, 1);
-  my_atomic_rwlock_wrunlock(&thread_running_lock);
-  return (num_thread_running+1);
+  my_atomic_rwlock_wrlock(lock);
+  (void) my_atomic_add32(value, -1);
+  my_atomic_rwlock_wrunlock(lock);
 }
 
-inline int32
-dec_thread_running()
+inline void
+inc_thread_running()
 {
-  int32 num_thread_running;
-  my_atomic_rwlock_wrlock(&thread_running_lock);
-  num_thread_running= my_atomic_add32(&thread_running, -1);
-  my_atomic_rwlock_wrunlock(&thread_running_lock);
-  return (num_thread_running-1);
+  thread_safe_increment32(&thread_running, &thread_running_lock);
 }
 
-inline int32
-get_thread_running()
+inline void
+dec_thread_running()
 {
-  int32 num_thread_running;
-  my_atomic_rwlock_wrlock(&thread_running_lock);
-  num_thread_running= my_atomic_load32(&thread_running);
-  my_atomic_rwlock_wrunlock(&thread_running_lock);
-  return num_thread_running;
+  thread_safe_decrement32(&thread_running, &thread_running_lock);
 }
 
 void set_server_version(void);

sql/sql_acl.cc

@@ -4530,12 +4530,16 @@ end:
   @see check_access
   @see check_table_access
 
-  @note This functions assumes that either number of tables to be inspected
+  @note
+     This functions assumes that either number of tables to be inspected
      by it is limited explicitly (i.e. is is not UINT_MAX) or table list
      used and thd->lex->query_tables_own_last value correspond to each
      other (the latter should be either 0 or point to next_global member
      of one of elements of this table list).
 
+     We delay locking of LOCK_grant until we really need it as we assume that
+     most privileges be resolved with user or db level accesses.
+
    @return Access status
      @retval FALSE Access granted; But column privileges might need to be
       checked.
@@ -4552,6 +4556,8 @@ bool check_grant(THD *thd, ulong want_access, TABLE_LIST *tables,
   Security_context *sctx= thd->security_ctx;
   uint i;
   ulong orig_want_access= want_access;
+  my_bool locked= 0;
+  GRANT_TABLE *grant_table;
   DBUG_ENTER("check_grant");
   DBUG_ASSERT(number > 0);
 
@@ -4575,11 +4581,9 @@ bool check_grant(THD *thd, ulong want_access, TABLE_LIST *tables,
     */
     tl->grant.orig_want_privilege= (want_access & ~SHOW_VIEW_ACL);
   }
+  number= i;
 
-  mysql_rwlock_rdlock(&LOCK_grant);
-  for (tl= tables;
-       tl && number-- && tl != first_not_own_table;
-       tl= tl->next_global)
+  for (tl= tables; number-- ; tl= tl->next_global)
   {
     sctx = test(tl->security_ctx) ? tl->security_ctx : thd->security_ctx;
 
@@ -4632,13 +4636,18 @@ bool check_grant(THD *thd, ulong want_access, TABLE_LIST *tables,
       }
       continue;
     }
-    GRANT_TABLE *grant_table= table_hash_search(sctx->host, sctx->ip,
-                                                tl->get_db_name(),
-                                                sctx->priv_user,
-                                                tl->get_table_name(),
-                                                FALSE);
 
-    if (!grant_table)
+    if (!locked)
+    {
+      locked= 1;
+      mysql_rwlock_rdlock(&LOCK_grant);
+    }
+
+    if (!(grant_table= table_hash_search(sctx->host, sctx->ip,
+                                         tl->get_db_name(),
+                                         sctx->priv_user,
+                                         tl->get_table_name(),
+                                         FALSE)))
     {
       want_access &= ~tl->grant.privilege;
       goto err;					// No grants
@@ -4665,11 +4674,13 @@ bool check_grant(THD *thd, ulong want_access, TABLE_LIST *tables,
       goto err;					// impossible
     }
   }
-  mysql_rwlock_unlock(&LOCK_grant);
+  if (locked)
+    mysql_rwlock_unlock(&LOCK_grant);
   DBUG_RETURN(FALSE);
 
 err:
-  mysql_rwlock_unlock(&LOCK_grant);
+  if (locked)
+    mysql_rwlock_unlock(&LOCK_grant);
   if (!no_errors)				// Not a silent skip of table
   {
     char command[128];

sql/sql_class.cc

@@ -349,29 +349,6 @@ void thd_set_thread_stack(THD *thd, char *stack_start)
   thd->thread_stack= stack_start;
 }
 
-/**
-  Lock connection data for the set of connections this connection
-  belongs to
-
-  @param thd                       THD object
-*/
-void thd_lock_thread_count(THD *)
-{
-  mysql_mutex_lock(&LOCK_thread_count);
-}
-
-/**
-  Lock connection data for the set of connections this connection
-  belongs to
-
-  @param thd                       THD object
-*/
-void thd_unlock_thread_count(THD *)
-{
-  mysql_cond_broadcast(&COND_thread_count);
-  mysql_mutex_unlock(&LOCK_thread_count);
-}
-
 /**
   Close the socket used by this connection
 
@@ -947,7 +924,14 @@ THD::THD()
   protocol_binary.init(this);
 
   tablespace_op=FALSE;
-  tmp= sql_rnd_with_mutex();
+
+  /*
+    Initialize the random generator. We call my_rnd() without a lock as
+    it's not really critical if two threads modifies the structure at the
+    same time.  We ensure that we have an unique number foreach thread
+    by adding the address of the stack.
+  */
+  tmp= (ulong) (my_rnd(&sql_rand) * 0xffffffff);
   my_rnd_init(&rand, tmp + (ulong) &rand, tmp + (ulong) ::global_query_id);
   substitute_null_with_insert_id = FALSE;
   thr_lock_info_init(&lock_info); /* safety: will be reset after start */
@@ -4342,17 +4326,8 @@ void THD::set_query_and_id(char *query_arg, uint32 query_length_arg,
 {
   mysql_mutex_lock(&LOCK_thd_data);
   set_query_inner(query_arg, query_length_arg, cs);
-  query_id= new_query_id;
   mysql_mutex_unlock(&LOCK_thd_data);
-}
-
-/** Assign a new value to thd->query_id.  */
-
-void THD::set_query_id(query_id_t new_query_id)
-{
-  mysql_mutex_lock(&LOCK_thd_data);
   query_id= new_query_id;
-  mysql_mutex_unlock(&LOCK_thd_data);
 }
 
 /** Assign a new value to thd->mysys_var.  */

sql/sql_class.h

@@ -3076,7 +3076,10 @@ public:
   { set_query(CSET_STRING()); }
   void set_query_and_id(char *query_arg, uint32 query_length_arg,
                         CHARSET_INFO *cs, query_id_t new_query_id);
-  void set_query_id(query_id_t new_query_id);
+  void set_query_id(query_id_t new_query_id)
+  {
+    query_id= new_query_id;
+  }
   void set_open_tables(TABLE *open_tables_arg)
   {
     mysql_mutex_lock(&LOCK_thd_data);

sql/sql_insert.cc

@@ -2038,9 +2038,9 @@ public:
     thd.unlink();				// Must be unlinked under lock
     my_free(thd.query());
     thd.security_ctx->user= thd.security_ctx->host=0;
-    thread_count--;
     delayed_insert_threads--;
     mysql_mutex_unlock(&LOCK_thread_count);
+    thread_safe_decrement32(&thread_count, &thread_count_lock);
     mysql_cond_broadcast(&COND_thread_count); /* Tell main we are ready */
   }
 
@@ -2175,9 +2175,9 @@ bool delayed_get_table(THD *thd, MDL_request *grl_protection_request,
     {
       if (!(di= new Delayed_insert()))
         goto end_create;
-      mysql_mutex_lock(&LOCK_thread_count);
-      thread_count++;
-      mysql_mutex_unlock(&LOCK_thread_count);
+
+      thread_safe_increment32(&thread_count, &thread_count_lock);
+
       /*
         Annotating delayed inserts is not supported.
       */

sql/sql_parse.cc

@@ -645,9 +645,10 @@ end:
   delete thd;
 
 #ifndef EMBEDDED_LIBRARY
-  mysql_mutex_lock(&LOCK_thread_count);
-  thread_count--;
+  thread_safe_decrement32(&thread_count, &thread_count_lock);
   in_bootstrap= FALSE;
+
+  mysql_mutex_lock(&LOCK_thread_count);
   mysql_cond_broadcast(&COND_thread_count);
   mysql_mutex_unlock(&LOCK_thread_count);
   my_thread_end();
@@ -930,9 +931,16 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
   thd->query_plan_flags= QPLAN_INIT;
   thd->lex->sql_command= SQLCOM_END; /* to avoid confusing VIEW detectors */
   thd->set_time();
-  thd->set_query_id(get_query_id());
   if (!(server_command_flags[command] & CF_SKIP_QUERY_ID))
-    next_query_id();
+    thd->set_query_id(next_query_id());
+  else
+  {
+    /*
+      ping, get statistics or similar stateless command.
+      No reason to increase query id here.
+    */
+    thd->set_query_id(get_query_id());
+  }
   inc_thread_running();
 
   if (!(server_command_flags[command] & CF_SKIP_QUESTIONS))
@@ -5021,6 +5029,10 @@ check_access(THD *thd, ulong want_access, const char *db, ulong *save_priv,
 
   if ((db != NULL) && (db != any_db))
   {
+    /*
+      Check if this is reserved database, like information schema or
+      performance schema
+    */
     const ACL_internal_schema_access *access;
     access= get_cached_schema_access(grant_internal_info, db);
     if (access)

vio/vio.c

@@ -213,9 +213,7 @@ Vio *vio_new(my_socket sd, enum enum_vio_type type, uint flags)
   if ((vio = (Vio*) my_malloc(sizeof(*vio),MYF(MY_WME))))
   {
     vio_init(vio, type, sd, 0, flags);
-    sprintf(vio->desc,
-	    (vio->type == VIO_TYPE_SOCKET ? "socket (%d)" : "TCP/IP (%d)"),
-	    vio->sd);
+    vio->desc= (vio->type == VIO_TYPE_SOCKET ? "socket" : "TCP/IP");
 #if !defined(__WIN__)
 #if !defined(NO_FCNTL_NONBLOCK)
     /*
@@ -257,7 +255,7 @@ Vio *vio_new_win32pipe(HANDLE hPipe)
   if ((vio = (Vio*) my_malloc(sizeof(Vio),MYF(MY_WME))))
   {
     vio_init(vio, VIO_TYPE_NAMEDPIPE, 0, hPipe, VIO_LOCALHOST);
-    strmov(vio->desc, "named pipe");
+    vio->desc= "named pipe";
   }
   DBUG_RETURN(vio);
 }
@@ -282,7 +280,7 @@ Vio *vio_new_win32shared_memory(HANDLE handle_file_map, HANDLE handle_map,
     vio->event_conn_closed= event_conn_closed;
     vio->shared_memory_remain= 0;
     vio->shared_memory_pos= handle_map;
-    strmov(vio->desc, "shared memory");
+    vio->desc= "shared memory";
   }
   DBUG_RETURN(vio);
 }