Backport of:

------------------------------------------------------------
revno: 2630.6.1
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-3726
timestamp: Tue 2008-05-27 13:45:34 +0400
message:
  Remove an unused argument from release_table_share().
  Remove unused members from TABLE_SHARE struct.
  Review comments in scope of WL#3726 "DDL locking for all metadata 
  objects"

sql/mysql_priv.h

@@ -1216,7 +1216,7 @@ uint create_table_def_key(THD *thd, char *key, TABLE_LIST *table_list,
                           bool tmp_table);
 TABLE_SHARE *get_table_share(THD *thd, TABLE_LIST *table_list, char *key,
                              uint key_length, uint db_flags, int *error);
-void release_table_share(TABLE_SHARE *share, enum release_type type);
+void release_table_share(TABLE_SHARE *share);
 TABLE_SHARE *get_cached_table_share(const char *db, const char *table_name);
 TABLE *open_ltable(THD *thd, TABLE_LIST *table_list, thr_lock_type update,
                    uint lock_flags);

sql/sql_base.cc

@@ -651,29 +651,17 @@ static TABLE_SHARE
                               db_flags, error));
 }
 
-
-/* 
+/**
   Mark that we are not using table share anymore.
 
-   SYNOPSIS
-     release_table_share()
-     share		Table share
-     release_type	How the release should be done:
-     			RELEASE_NORMAL
-                         - Release without checking
-                        RELEASE_WAIT_FOR_DROP
-                         - Don't return until we get a signal that the
-                           table is deleted or the thread is killed.
-
-   IMPLEMENTATION
-     If ref_count goes to zero and (we have done a refresh or if we have
-     already too many open table shares) then delete the definition.
+  @param  share   Table share
 
-     If type == RELEASE_WAIT_FOR_DROP then don't return until we get a signal
-     that the table is deleted or the thread is killed.
+  If the share has no open tables and (we have done a refresh or
+  if we have already too many open table shares) then delete the
+  definition.
 */
 
-void release_table_share(TABLE_SHARE *share, enum release_type type)
+void release_table_share(TABLE_SHARE *share)
 {
   bool to_be_deleted= 0;
   DBUG_ENTER("release_table_share");
@@ -818,7 +806,7 @@ void close_handle_and_leave_table_as_lock(TABLE *table)
   table->file->close();
   table->db_stat= 0;                            // Mark file closed
   table_def_change_share(table, share);
-  release_table_share(table->s, RELEASE_NORMAL);
+  release_table_share(table->s);
   table->s= share;
   table->file->change_table_ptr(table, table->s);
 
@@ -2568,7 +2556,7 @@ bool check_if_table_exists(THD *thd, TABLE_LIST *table, bool *exists)
 void table_share_release_hook(void *share)
 {
   pthread_mutex_lock(&LOCK_open);
-  release_table_share((TABLE_SHARE*)share, RELEASE_NORMAL);
+  release_table_share((TABLE_SHARE*) share);
   broadcast_refresh();
   pthread_mutex_unlock(&LOCK_open);
 }
@@ -2902,7 +2890,7 @@ TABLE *open_table(THD *thd, TABLE_LIST *table_list, MEM_ROOT *mem_root,
         goto err_unlock;
 
       /* TODO: Don't free this */
-      release_table_share(share, RELEASE_NORMAL);
+      release_table_share(share);
 
       if (flags & OPEN_VIEW_NO_PARSE)
       {
@@ -2978,7 +2966,7 @@ TABLE *open_table(THD *thd, TABLE_LIST *table_list, MEM_ROOT *mem_root,
     {
       if (action)
         *action= OT_BACK_OFF_AND_RETRY;
-      release_table_share(share, RELEASE_NORMAL);
+      release_table_share(share);
       pthread_mutex_unlock(&LOCK_open);
       DBUG_RETURN(0);
     }
@@ -2991,7 +2979,7 @@ TABLE *open_table(THD *thd, TABLE_LIST *table_list, MEM_ROOT *mem_root,
     table= share->free_tables.head();
     table_def_use_table(thd, table);
     /* We need to release share as we have EXTRA reference to it in our hands. */
-    release_table_share(share, RELEASE_NORMAL);
+    release_table_share(share);
   }
   else
   {
@@ -3095,7 +3083,7 @@ TABLE *open_table(THD *thd, TABLE_LIST *table_list, MEM_ROOT *mem_root,
   DBUG_RETURN(table);
 
 err_unlock:
-  release_table_share(share, RELEASE_NORMAL);
+  release_table_share(share);
 err_unlock2:
   pthread_mutex_unlock(&LOCK_open);
   mdl_release_lock(&thd->mdl_context, mdl_lock);
@@ -3758,13 +3746,13 @@ bool tdc_open_view(THD *thd, TABLE_LIST *table_list, const char *alias,
                     flags, thd->open_options, &not_used, table_list,
                     mem_root))
   {
-    release_table_share(share, RELEASE_NORMAL);
+    release_table_share(share);
     pthread_mutex_unlock(&LOCK_open);
     return FALSE;
   }
 
   my_error(ER_WRONG_OBJECT, MYF(0), share->db.str, share->table_name.str, "VIEW");
-  release_table_share(share, RELEASE_NORMAL);
+  release_table_share(share);
 err:
   pthread_mutex_unlock(&LOCK_open);
   return TRUE;
@@ -3838,7 +3826,7 @@ static bool reopen_table_entry(THD *thd, TABLE *entry, TABLE_LIST *table_list,
     if (table_list->i_s_requested_object &  OPEN_TABLE_ONLY)
       goto err;
     /* Attempt to reopen view will bring havoc to upper layers anyway. */
-    release_table_share(share, RELEASE_NORMAL);
+    release_table_share(share);
     my_error(ER_WRONG_OBJECT, MYF(0), share->db.str, share->table_name.str,
              "BASE TABLE");
     DBUG_RETURN(1);
@@ -3871,7 +3859,7 @@ static bool reopen_table_entry(THD *thd, TABLE *entry, TABLE_LIST *table_list,
       if (share->ref_count != 1)
         goto err;
 
-      release_table_share(share, RELEASE_NORMAL);
+      release_table_share(share);
 
       if (ha_create_table_from_engine(thd, table_list->db,
                                       table_list->table_name))
@@ -3887,7 +3875,7 @@ static bool reopen_table_entry(THD *thd, TABLE *entry, TABLE_LIST *table_list,
     entry->s->version= 0;
 
     /* TODO: We don't need to release share here. */
-    release_table_share(share, RELEASE_NORMAL);
+    release_table_share(share);
     pthread_mutex_unlock(&LOCK_open);
     error= (int)auto_repair_table(thd, table_list);
     pthread_mutex_lock(&LOCK_open);
@@ -3907,7 +3895,7 @@ static bool reopen_table_entry(THD *thd, TABLE *entry, TABLE_LIST *table_list,
   DBUG_RETURN(0);
 
 err:
-  release_table_share(share, RELEASE_NORMAL);
+  release_table_share(share);
   DBUG_RETURN(1);
 }
 
@@ -4031,7 +4019,7 @@ static bool auto_repair_table(THD *thd, TABLE_LIST *table_list)
   pthread_mutex_lock(&LOCK_open);
 
 end_with_lock_open:
-  release_table_share(share, RELEASE_NORMAL);
+  release_table_share(share);
   pthread_mutex_unlock(&LOCK_open);
   return result;
 }

sql/sql_plist.h

@@ -62,7 +62,7 @@ class I_P_List
 public:
   I_P_List() : first(NULL) { };
   inline void empty()      { first= NULL; }
-  inline bool is_empty()   { return (first == NULL); }
+  inline bool is_empty() const { return (first == NULL); }
   inline void push_front(T* a)
   {
     *B::next_ptr(a)= first;

sql/sql_show.cc

@@ -3206,7 +3206,7 @@ static int fill_schema_table_from_frm(THD *thd,TABLE *table,
   }
 
 err_share:
-  release_table_share(share, RELEASE_NORMAL);
+  release_table_share(share);
 
 err_unlock:
   pthread_mutex_unlock(&LOCK_open);

sql/sql_table.cc

@@ -4469,7 +4469,7 @@ static int prepare_for_repair(THD *thd, TABLE_LIST *table_list,
 
     if (open_table_from_share(thd, share, "", 0, 0, 0, &tmp_table, FALSE))
     {
-      release_table_share(share, RELEASE_NORMAL);
+      release_table_share(share);
       pthread_mutex_unlock(&LOCK_open);
       DBUG_RETURN(0);                           // Out of memory
     }

sql/sql_view.cc

@@ -1647,7 +1647,7 @@ bool mysql_drop_view(THD *thd, TABLE_LIST *views, enum_drop_mode drop_mode)
       share->ref_count++;
       share->version= 0;
       pthread_mutex_unlock(&share->mutex);
-      release_table_share(share, RELEASE_WAIT_FOR_DROP);
+      release_table_share(share);
     }
     query_cache_invalidate3(thd, view, 0);
     sp_cache_invalidate();

sql/table.cc

@@ -321,7 +321,6 @@ TABLE_SHARE *alloc_table_share(TABLE_LIST *table_list, char *key,
 
     memcpy((char*) &share->mem_root, (char*) &mem_root, sizeof(mem_root));
     pthread_mutex_init(&share->mutex, MY_MUTEX_INIT_FAST);
-    pthread_cond_init(&share->cond, NULL);
   }
   DBUG_RETURN(share);
 }
@@ -418,16 +417,9 @@ void free_table_share(TABLE_SHARE *share)
   */
   if (share->tmp_table == NO_TMP_TABLE)
   {
-    /* share->mutex is locked in release_table_share() */
-    while (share->waiting_on_cond)
-    {
-      pthread_cond_broadcast(&share->cond);
-      pthread_cond_wait(&share->cond, &share->mutex);
-    }
     /* No thread refers to this anymore */
     pthread_mutex_unlock(&share->mutex);
     pthread_mutex_destroy(&share->mutex);
-    pthread_cond_destroy(&share->cond);
   }
   my_hash_free(&share->name_hash);
   
@@ -2001,7 +1993,7 @@ int closefrm(register TABLE *table, bool free_share)
   if (free_share)
   {
     if (table->s->tmp_table == NO_TMP_TABLE)
-      release_table_share(table->s, RELEASE_NORMAL);
+      release_table_share(table->s);
     else
       free_table_share(table->s);
   }

sql/table.h

@@ -313,7 +313,6 @@ struct TABLE_SHARE
   TYPELIB fieldnames;			/* Pointer to fieldnames */
   TYPELIB *intervals;			/* pointer to interval info */
   pthread_mutex_t mutex;                /* For locking the share  */
-  pthread_cond_t cond;			/* To signal that share is ready */
   TABLE_SHARE *next, **prev;            /* Link to unused shares */
 
   /*
@@ -410,7 +409,6 @@ struct TABLE_SHARE
   bool crashed;
   bool is_view;
   bool name_lock, replace_with_name_lock;
-  bool waiting_on_cond;                 /* Protection against free */
   ulong table_map_id;                   /* for row-based replication */
   ulonglong table_map_version;