Commit 6e5c98ea authored by unknown's avatar unknown
Browse files

plugin_foreach - don't hold the lock when calling the function

parent b1e2cfce

sql/sql_plugin.cc

+40 −18
Original line number Diff line number Diff line
@@ -63,6 +63,8 @@ static HASH plugin_hash[MYSQL_MAX_PLUGIN_TYPE_NUM]; 
static rw_lock_t THR_LOCK_plugin;

static bool initialized= 0;



static int plugin_array_version=0;



/* prototypes */

my_bool plugin_register_builtin(struct st_mysql_plugin *plugin);

void plugin_load(void);
@@ -448,6 +450,7 @@ static my_bool plugin_add(const LEX_STRING *name, const LEX_STRING *dl, int repo 
      tmp.state= PLUGIN_IS_UNINITIALIZED;

      if (! (tmp_plugin_ptr= plugin_insert_or_reuse(&tmp)))

        goto err;

      plugin_array_version++;

      if (my_hash_insert(&plugin_hash[plugin->type], (byte*)tmp_plugin_ptr))

      {

        tmp_plugin_ptr->state= PLUGIN_IS_FREED;
@@ -504,6 +507,7 @@ static void plugin_del(const LEX_STRING *name) 
    hash_delete(&plugin_hash[plugin->plugin->type], (byte*)plugin);

    plugin_dl_del(&plugin->plugin_dl->dl);

    plugin->state= PLUGIN_IS_FREED;

    plugin_array_version++;

  }

  DBUG_VOID_RETURN;

}
@@ -639,7 +643,7 @@ static byte *get_hash_key(const byte *buff, uint *length, 
*/

int plugin_init(int skip_dynamic_loading)

{

  int i;

  uint i;

  struct st_mysql_plugin **builtins;

  struct st_mysql_plugin *plugin;

  DBUG_ENTER("plugin_init");
@@ -939,43 +943,61 @@ my_bool mysql_uninstall_plugin(THD *thd, const LEX_STRING *name) 
  DBUG_RETURN(TRUE);

}





my_bool plugin_foreach(THD *thd, plugin_foreach_func *func,

                       int type, void *arg)

{

  uint idx;

  struct st_plugin_int *plugin;

  uint idx, total;

  struct st_plugin_int *plugin, **plugins;

  int version=plugin_array_version;

  DBUG_ENTER("plugin_foreach");

  rw_rdlock(&THR_LOCK_plugin);



  rw_rdlock(&THR_LOCK_plugin);

  if (type == MYSQL_ANY_PLUGIN)

  {

    for (idx= 0; idx < plugin_array.elements; idx++)

    total=plugin_array.elements;

    plugins=(struct st_plugin_int **)my_alloca(total*sizeof(*plugins));

    for (idx= 0; idx < total; idx++)

    {

      plugin= dynamic_element(&plugin_array, idx, struct st_plugin_int *);



      /* FREED records may have garbage pointers */

      if ((plugin->state != PLUGIN_IS_FREED) &&

          func(thd, plugin, arg))

        goto err;

      if (plugin->state == PLUGIN_IS_FREED)

        continue;

      plugins[idx]= plugin;

    }

  }

  else

  {

    HASH *hash= &plugin_hash[type];

    for (idx= 0; idx < hash->records; idx++)

    total=hash->records;

    plugins=(struct st_plugin_int **)my_alloca(total*sizeof(*plugins));

    for (idx= 0; idx < total; idx++)

    {

      plugin= (struct st_plugin_int *) hash_element(hash, idx);

      if ((plugin->state != PLUGIN_IS_FREED) &&

          (plugin->state != PLUGIN_IS_DELETED) &&

          func(thd, plugin, arg))

        goto err;

      if (plugin->state == PLUGIN_IS_FREED)

        continue;

      plugins[idx]= plugin;

    }

  }

  rw_unlock(&THR_LOCK_plugin);



  for (idx= 0; idx < total; idx++)

  {

    plugin= plugins[idx];

    if (unlikely(version != plugin_array_version))

    {

      rw_rdlock(&THR_LOCK_plugin);

      for (uint i=idx; i < total; i++)

        if (plugins[i]->state == PLUGIN_IS_FREED)

          plugins[i]=0;

      rw_unlock(&THR_LOCK_plugin);

    }

    if (plugin && func(thd, plugin, arg))

        goto err;

  }



  my_afree(plugins);

  DBUG_RETURN(FALSE);

err:

  rw_unlock(&THR_LOCK_plugin);

  my_afree(plugins);

  DBUG_RETURN(TRUE);

}