diff options
| author | ingo@mysql.com <> | 2006-06-26 19:14:35 +0200 |
|---|---|---|
| committer | ingo@mysql.com <> | 2006-06-26 19:14:35 +0200 |
| commit | d27a15a81c8806ff6d41ccd0303909f0c5a9f174 (patch) | |
| tree | f72941273e5da9bb2f5853ff33357f7b0c0a118c /sql/sql_table.cc | |
| parent | fa98891ee74531b05d0e9f7c5e3a2cce9a751288 (diff) | |
| download | mariadb-git-d27a15a81c8806ff6d41ccd0303909f0c5a9f174.tar.gz | |
Bug#16986 - Deadlock condition with MyISAM tables
Addendum fixes after changing the condition variable
for the global read lock.
The stress test suite revealed some deadlocks. Some were
related to the new condition variable (COND_global_read_lock)
and some were general problems with the global read lock.
It is now necessary to signal COND_global_read_lock whenever
COND_refresh is signalled.
We need to wait for the release of a global read lock if one
is set before every operation that requires a write lock.
But we must not wait if we have locked tables by LOCK TABLES.
After setting a global read lock a thread waits until all
write locks are released.
Diffstat (limited to 'sql/sql_table.cc')
| -rw-r--r-- | sql/sql_table.cc | 9 |
1 files changed, 3 insertions, 6 deletions
diff --git a/sql/sql_table.cc b/sql/sql_table.cc index 275cfbaa088..49f84aed966 100644 --- a/sql/sql_table.cc +++ b/sql/sql_table.cc @@ -1674,8 +1674,6 @@ bool mysql_create_table(THD *thd,const char *db, const char *table_name, my_error(ER_TABLE_EXISTS_ERROR, MYF(0), alias); DBUG_RETURN(TRUE); } - if (wait_if_global_read_lock(thd, 0, 1)) - DBUG_RETURN(TRUE); VOID(pthread_mutex_lock(&LOCK_open)); if (!internal_tmp_table && !(create_info->options & HA_LEX_CREATE_TMP_TABLE)) { @@ -1743,7 +1741,6 @@ bool mysql_create_table(THD *thd,const char *db, const char *table_name, end: VOID(pthread_mutex_unlock(&LOCK_open)); - start_waiting_global_read_lock(thd); thd->proc_info="After create"; DBUG_RETURN(error); @@ -1923,7 +1920,7 @@ void close_cached_table(THD *thd, TABLE *table) thd->open_tables=unlink_open_table(thd,thd->open_tables,table); /* When lock on LOCK_open is freed other threads can continue */ - pthread_cond_broadcast(&COND_refresh); + broadcast_refresh(); DBUG_VOID_RETURN; } @@ -3894,7 +3891,7 @@ bool mysql_alter_table(THD *thd,char *new_db, char *new_name, if (error) { VOID(pthread_mutex_unlock(&LOCK_open)); - VOID(pthread_cond_broadcast(&COND_refresh)); + broadcast_refresh(); goto err; } thd->proc_info="end"; @@ -3904,7 +3901,7 @@ bool mysql_alter_table(THD *thd,char *new_db, char *new_name, Query_log_event qinfo(thd, thd->query, thd->query_length, FALSE, FALSE); mysql_bin_log.write(&qinfo); } - VOID(pthread_cond_broadcast(&COND_refresh)); + broadcast_refresh(); VOID(pthread_mutex_unlock(&LOCK_open)); #ifdef HAVE_BERKELEY_DB if (old_db_type == DB_TYPE_BERKELEY_DB) |