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_handler.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_handler.cc')
| -rw-r--r-- | sql/sql_handler.cc | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/sql/sql_handler.cc b/sql/sql_handler.cc index 1cd7778a053..0193d4d5355 100644 --- a/sql/sql_handler.cc +++ b/sql/sql_handler.cc @@ -254,7 +254,8 @@ err: DESCRIPTION Though this function takes a list of tables, only the first list entry - will be closed. Broadcasts a COND_refresh condition. + will be closed. + Broadcasts refresh if it closed the table. RETURN FALSE ok @@ -291,7 +292,7 @@ bool mysql_ha_close(THD *thd, TABLE_LIST *tables) if (close_thread_table(thd, table_ptr)) { /* Tell threads waiting for refresh that something has happened */ - VOID(pthread_cond_broadcast(&COND_refresh)); + broadcast_refresh(); } VOID(pthread_mutex_unlock(&LOCK_open)); } @@ -608,7 +609,7 @@ err0: tables are closed (if MYSQL_HA_FLUSH_ALL) is set. If 'tables' is NULL and MYSQL_HA_FLUSH_ALL is not set, all HANDLER tables marked for flush are closed. - Broadcasts a COND_refresh condition, for every table closed. + Broadcasts refresh for every table closed. NOTE Since mysql_ha_flush() is called when the base table has to be closed, @@ -704,7 +705,7 @@ int mysql_ha_flush(THD *thd, TABLE_LIST *tables, uint mode_flags, MYSQL_HA_REOPEN_ON_USAGE mark for reopen. DESCRIPTION - Broadcasts a COND_refresh condition, for every table closed. + Broadcasts refresh if it closed the table. The caller must lock LOCK_open. RETURN @@ -742,7 +743,7 @@ static int mysql_ha_flush_table(THD *thd, TABLE **table_ptr, uint mode_flags) if (close_thread_table(thd, table_ptr)) { /* Tell threads waiting for refresh that something has happened */ - VOID(pthread_cond_broadcast(&COND_refresh)); + broadcast_refresh(); } DBUG_RETURN(0); |