diff options
Diffstat (limited to 'sql/sql_class.cc')
| -rw-r--r-- | sql/sql_class.cc | 62 |
1 files changed, 44 insertions, 18 deletions
diff --git a/sql/sql_class.cc b/sql/sql_class.cc index 1cc9a6a61d3..f4fd27ad5d1 100644 --- a/sql/sql_class.cc +++ b/sql/sql_class.cc @@ -1531,16 +1531,32 @@ void THD::reset_db(const LEX_CSTRING *new_db) /* Do operations that may take a long time */ -void THD::cleanup(void) +void THD::cleanup(bool have_mutex) { DBUG_ENTER("THD::cleanup"); DBUG_ASSERT(cleanup_done == 0); - set_killed(KILL_CONNECTION); + if (have_mutex) + set_killed_no_mutex(KILL_CONNECTION,0,0); + else + set_killed(KILL_CONNECTION); #ifdef WITH_WSREP if (wsrep_cs().state() != wsrep::client_state::s_none) { + // Below wsrep-lib function will take THD::LOCK_thd_data + // I do not like this, but at the moment there is no + // alternative. + if (have_mutex) + { + mysql_mutex_unlock(&LOCK_thd_kill); + mysql_mutex_unlock(&LOCK_thd_data); + } wsrep_cs().cleanup(); + if (have_mutex) + { + mysql_mutex_lock(&LOCK_thd_data); + mysql_mutex_lock(&LOCK_thd_kill); + } } wsrep_client_thread= false; #endif /* WITH_WSREP */ @@ -1614,6 +1630,28 @@ void THD::cleanup(void) void THD::free_connection() { DBUG_ASSERT(free_connection_done == 0); + /* Make sure threads are not available via server_threads. */ + assert_not_linked(); + + /* + Other threads may have a lock on THD::LOCK_thd_data or + THD::LOCK_thd_kill to ensure that this THD is not deleted + while they access it. The following mutex_lock ensures + that no one else is using this THD and it's now safe to + continue. + + For example consider KILL-statement execution on + sql_parse.cc kill_one_thread() that will use + THD::LOCK_thd_data to protect victim thread during + THD::awake(). + */ + mysql_mutex_lock(&LOCK_thd_data); + mysql_mutex_lock(&LOCK_thd_kill); + +#ifdef WITH_WSREP + delete wsrep_rgi; + wsrep_rgi= 0; +#endif my_free((char*) db.str); db= null_clex_str; #ifndef EMBEDDED_LIBRARY @@ -1622,8 +1660,8 @@ void THD::free_connection() net.vio= 0; net_end(&net); #endif - if (!cleanup_done) - cleanup(); + if (!cleanup_done) + cleanup(true); // We have locked THD::LOCK_thd_kill ha_close_connection(this); plugin_thdvar_cleanup(this); mysql_audit_free_thd(this); @@ -1635,6 +1673,8 @@ void THD::free_connection() profiling.restart(); // Reset profiling #endif debug_sync_reset_thread(this); + mysql_mutex_unlock(&LOCK_thd_kill); + mysql_mutex_unlock(&LOCK_thd_data); } /* @@ -1690,24 +1730,10 @@ THD::~THD() if (!status_in_global) add_status_to_global(); - /* - Other threads may have a lock on LOCK_thd_kill to ensure that this - THD is not deleted while they access it. The following mutex_lock - ensures that no one else is using this THD and it's now safe to delete - */ - if (WSREP_NNULL(this)) mysql_mutex_lock(&LOCK_thd_data); - mysql_mutex_lock(&LOCK_thd_kill); - mysql_mutex_unlock(&LOCK_thd_kill); - if (WSREP_NNULL(this)) mysql_mutex_unlock(&LOCK_thd_data); - if (!free_connection_done) free_connection(); #ifdef WITH_WSREP - if (wsrep_rgi != NULL) { - delete wsrep_rgi; - wsrep_rgi = NULL; - } mysql_cond_destroy(&COND_wsrep_thd); #endif mdl_context.destroy(); |