From e43791d4dc8feb2c02a08ce73c0bb0e2c320018c Mon Sep 17 00:00:00 2001 From: Sergey Vojtovich Date: Wed, 2 Oct 2019 15:23:59 +0400 Subject: Cleanup EITS Moved EITS allocation inside read_statistics_for_tables_if_needed(). Removed redundant is_safe argument. --- sql/sql_statistics.cc | 53 +++++++++++++++++++++++++++++++++------------------ 1 file changed, 34 insertions(+), 19 deletions(-) (limited to 'sql/sql_statistics.cc') diff --git a/sql/sql_statistics.cc b/sql/sql_statistics.cc index 52b3811e60d..e18cec589be 100644 --- a/sql/sql_statistics.cc +++ b/sql/sql_statistics.cc @@ -2216,8 +2216,6 @@ inline bool statistics_for_command_is_needed(THD *thd) thd Thread handler @param table_share Table share for which the memory for statistical data is allocated - @param - is_safe TRUE <-> at any time only one thread can perform the function @note The function allocates the memory for the statistical data on a table in the @@ -2226,8 +2224,6 @@ inline bool statistics_for_command_is_needed(THD *thd) mysql.index_stats. The memory is allocated for the statistics on the table, on the tables's columns, and on the table's indexes. The memory is allocated in the table_share's mem_root. - If the parameter is_safe is TRUE then it is guaranteed that at any given time - only one thread is executed the code of the function. @retval 0 If the memory for all statistical data has been successfully allocated @@ -2246,16 +2242,10 @@ inline bool statistics_for_command_is_needed(THD *thd) Here the second and the third threads try to allocate the memory for statistical data at the same time. The precautions are taken to guarantee the correctness of the allocation. - - @note - Currently the function always is called with the parameter is_safe set - to FALSE. */ -int alloc_statistics_for_table_share(THD* thd, TABLE_SHARE *table_share, - bool is_safe) +static int alloc_statistics_for_table_share(THD* thd, TABLE_SHARE *table_share) { - Field **field_ptr; KEY *key_info, *end; TABLE_STATISTICS_CB *stats_cb= &table_share->stats_cb; @@ -2268,13 +2258,11 @@ int alloc_statistics_for_table_share(THD* thd, TABLE_SHARE *table_share, if (!statistics_for_command_is_needed(thd)) DBUG_RETURN(1); - if (!is_safe) - mysql_mutex_lock(&table_share->LOCK_share); + mysql_mutex_lock(&table_share->LOCK_share); if (stats_cb->stats_can_be_read) { - if (!is_safe) - mysql_mutex_unlock(&table_share->LOCK_share); + mysql_mutex_unlock(&table_share->LOCK_share); DBUG_RETURN(0); } @@ -2285,8 +2273,7 @@ int alloc_statistics_for_table_share(THD* thd, TABLE_SHARE *table_share, sizeof(Table_statistics)); if (!table_stats) { - if (!is_safe) - mysql_mutex_unlock(&table_share->LOCK_share); + mysql_mutex_unlock(&table_share->LOCK_share); DBUG_RETURN(1); } memset(table_stats, 0, sizeof(Table_statistics)); @@ -2358,8 +2345,7 @@ int alloc_statistics_for_table_share(THD* thd, TABLE_SHARE *table_share, if (column_stats && index_stats && idx_avg_frequency) stats_cb->stats_can_be_read= TRUE; - if (!is_safe) - mysql_mutex_unlock(&table_share->LOCK_share); + mysql_mutex_unlock(&table_share->LOCK_share); DBUG_RETURN(0); } @@ -3264,6 +3250,35 @@ int read_statistics_for_tables_if_needed(THD *thd, TABLE_LIST *tables) DBUG_ENTER("read_statistics_for_tables_if_needed"); + for (TABLE_LIST *tl= tables; tl; tl= tl->next_global) + { + if (get_use_stat_tables_mode(thd) > NEVER && tl->table) + { + TABLE_SHARE *table_share= tl->table->s; + if (table_share && table_share->table_category == TABLE_CATEGORY_USER && + table_share->tmp_table == NO_TMP_TABLE) + { + if (table_share->stats_cb.stats_can_be_read || + !alloc_statistics_for_table_share(thd, table_share)) + { + if (table_share->stats_cb.stats_can_be_read) + { + KEY *key_info= table_share->key_info; + KEY *key_info_end= key_info + table_share->keys; + KEY *table_key_info= tl->table->key_info; + for ( ; key_info < key_info_end; key_info++, table_key_info++) + table_key_info->read_stats= key_info->read_stats; + Field **field_ptr= table_share->field; + Field **table_field_ptr= tl->table->field; + for ( ; *field_ptr; field_ptr++, table_field_ptr++) + (*table_field_ptr)->read_stats= (*field_ptr)->read_stats; + tl->table->stats_is_read= table_share->stats_cb.stats_is_read; + } + } + } + } + } + DEBUG_SYNC(thd, "statistics_read_start"); if (!statistics_for_tables_is_needed(thd, tables)) -- cgit v1.2.1 From adefaeffcce7c4ae0844f72dd920603b35285d40 Mon Sep 17 00:00:00 2001 From: Sergey Vojtovich Date: Wed, 2 Oct 2019 16:04:52 +0400 Subject: MDEV-19536 - Server crash or ASAN heap-use-after-free in is_temporary_table / read_statistics_for_tables_if_needed Regression after 279a907, read_statistics_for_tables_if_needed() was called after open_normal_and_derived_tables() failure. Fixed by moving read_statistics_for_tables() call to a branch of get_schema_stat_record() where result of open_normal_and_derived_tables() is checked. Removed THD::force_read_stats, added read_statistics_for_tables() instead. Simplified away statistics_for_command_is_needed(). --- sql/sql_statistics.cc | 83 +++++++++++++++++---------------------------------- 1 file changed, 27 insertions(+), 56 deletions(-) (limited to 'sql/sql_statistics.cc') diff --git a/sql/sql_statistics.cc b/sql/sql_statistics.cc index e18cec589be..4a1ed9cde4e 100644 --- a/sql/sql_statistics.cc +++ b/sql/sql_statistics.cc @@ -2160,54 +2160,6 @@ int alloc_statistics_for_table(THD* thd, TABLE *table) } -/** - @brief - Check whether any persistent statistics for the processed command is needed - - @param - thd The thread handle - - @details - The function checks whether any persitent statistics for the processed - command is needed to be read. - - @retval - TRUE statistics is needed to be read - @retval - FALSE Otherwise -*/ - -static -inline bool statistics_for_command_is_needed(THD *thd) -{ - if (thd->bootstrap || thd->variables.use_stat_tables == NEVER) - return FALSE; - - if (thd->force_read_stats) - return TRUE; - - switch(thd->lex->sql_command) { - case SQLCOM_SELECT: - case SQLCOM_INSERT: - case SQLCOM_INSERT_SELECT: - case SQLCOM_UPDATE: - case SQLCOM_UPDATE_MULTI: - case SQLCOM_DELETE: - case SQLCOM_DELETE_MULTI: - case SQLCOM_REPLACE: - case SQLCOM_REPLACE_SELECT: - case SQLCOM_CREATE_TABLE: - case SQLCOM_SET_OPTION: - case SQLCOM_DO: - break; - default: - return FALSE; - } - - return TRUE; -} - - /** @brief Allocate memory for the statistical data used by a table share @@ -2255,9 +2207,6 @@ static int alloc_statistics_for_table_share(THD* thd, TABLE_SHARE *table_share) DEBUG_SYNC(thd, "statistics_mem_alloc_start1"); DEBUG_SYNC(thd, "statistics_mem_alloc_start2"); - if (!statistics_for_command_is_needed(thd)) - DBUG_RETURN(1); - mysql_mutex_lock(&table_share->LOCK_share); if (stats_cb->stats_can_be_read) @@ -3110,9 +3059,6 @@ bool statistics_for_tables_is_needed(THD *thd, TABLE_LIST *tables) { if (!tables) return FALSE; - - if (!statistics_for_command_is_needed(thd)) - return FALSE; /* Do not read statistics for any query that explicity involves @@ -3244,15 +3190,40 @@ int read_histograms_for_table(THD *thd, TABLE *table, TABLE_LIST *stat_tables) */ int read_statistics_for_tables_if_needed(THD *thd, TABLE_LIST *tables) +{ + switch (thd->lex->sql_command) { + case SQLCOM_SELECT: + case SQLCOM_INSERT: + case SQLCOM_INSERT_SELECT: + case SQLCOM_UPDATE: + case SQLCOM_UPDATE_MULTI: + case SQLCOM_DELETE: + case SQLCOM_DELETE_MULTI: + case SQLCOM_REPLACE: + case SQLCOM_REPLACE_SELECT: + case SQLCOM_CREATE_TABLE: + case SQLCOM_SET_OPTION: + case SQLCOM_DO: + return read_statistics_for_tables(thd, tables); + default: + return 0; + } +} + + +int read_statistics_for_tables(THD *thd, TABLE_LIST *tables) { TABLE_LIST stat_tables[STATISTICS_TABLES]; Open_tables_backup open_tables_backup; - DBUG_ENTER("read_statistics_for_tables_if_needed"); + DBUG_ENTER("read_statistics_for_tables"); + + if (thd->bootstrap || thd->variables.use_stat_tables == NEVER) + DBUG_RETURN(0); for (TABLE_LIST *tl= tables; tl; tl= tl->next_global) { - if (get_use_stat_tables_mode(thd) > NEVER && tl->table) + if (tl->table) { TABLE_SHARE *table_share= tl->table->s; if (table_share && table_share->table_category == TABLE_CATEGORY_USER && -- cgit v1.2.1