#At file:///home/svoj/devel/bzr-mysql/mysql-5.1-bugteam-bug39053/ based on revid:sergey.glukhov@stripped
3436 Sergey Vojtovich 2010-03-31
BUG#39053 - UNISTALL PLUGIN does not allow the storage engine
to cleanup open connections
It was possible to UNINSTALL storage engine plugin when binding
between THD object and storage engine is still active (e.g. in
the middle of transaction).
To avoid unclean deactivation (uninstall) of storage engine plugin
in the middle of transaction, additional storage engine plugin
locks are acquired by thd_set_ha_data().
If ha_data is not null and storage engine plugin was not locked
by thd_set_ha_data() in this connection before, storage engine
plugin gets locked.
If ha_data is null and storage engine plugin was locked by
thd_set_ha_data() in this connection before, storage engine
plugin lock gets released.
If handlerton::close_connection() didn't reset ha_data, server does
it immediately after calling handlerton::close_connection().
Note that this is just a framework fix, storage engines must switch
to thd_set_ha_data() from thd_ha_data() if they want to see fit.
@ include/mysql/plugin.h
As thd_{get|set}_ha_data() have some extra logic now, they
must be implemented on server side.
@ include/mysql/plugin.h.pp
As thd_{get|set}_ha_data() have some extra logic now, they
must be implemented on server side.
@ sql/handler.cc
Make sure ha_data is reset and ha_data_lock is released.
@ sql/sql_class.cc
As thd_{get|set}_ha_data() have some extra logic now, they
must be implemented on server side.
@ sql/sql_class.h
Added ha_data_lock.
modified:
include/mysql/plugin.h
include/mysql/plugin.h.pp
sql/handler.cc
sql/sql_class.cc
sql/sql_class.h
=== modified file 'include/mysql/plugin.h'
--- a/include/mysql/plugin.h 2010-03-16 13:15:19 +0000
+++ b/include/mysql/plugin.h 2010-03-31 12:04:11 +0000
@@ -801,30 +801,37 @@ void mysql_query_cache_invalidate4(MYSQL
const char *key, unsigned int key_length,
int using_trx);
-#ifdef __cplusplus
-}
-#endif
-#ifdef __cplusplus
/**
Provide a handler data getter to simplify coding
*/
-inline
-void *
-thd_get_ha_data(const MYSQL_THD thd, const struct handlerton *hton)
-{
- return *thd_ha_data(thd, hton);
-}
+void *thd_get_ha_data(const MYSQL_THD thd, const struct handlerton *hton);
+
/**
Provide a handler data setter to simplify coding
+
+ @details
+ Set ha_data pointer (storage engine per-connection information).
+
+ To avoid unclean deactivation (uninstall) of storage engine plugin
+ in the middle of transaction, additional storage engine plugin
+ locks are acquired.
+
+ If ha_data is not null and storage engine plugin was not locked
+ by thd_set_ha_data() in this connection before, storage engine
+ plugin gets locked.
+
+ If ha_data is null and storage engine plugin was locked by
+ thd_set_ha_data() in this connection before, storage engine
+ plugin lock gets released.
+
+ If handlerton::close_connection() didn't reset ha_data, server does
+ it immediately after calling handlerton::close_connection().
*/
-inline
-void
-thd_set_ha_data(const MYSQL_THD thd, const struct handlerton *hton,
- const void *ha_data)
-{
- *thd_ha_data(thd, hton)= (void*) ha_data;
+void thd_set_ha_data(const MYSQL_THD thd, const struct handlerton *hton,
+ const void *ha_data);
+#ifdef __cplusplus
}
#endif
=== modified file 'include/mysql/plugin.h.pp'
--- a/include/mysql/plugin.h.pp 2008-06-17 12:27:04 +0000
+++ b/include/mysql/plugin.h.pp 2010-03-31 12:04:11 +0000
@@ -137,3 +137,6 @@ void thd_get_xid(const void* thd, MYSQL_
void mysql_query_cache_invalidate4(void* thd,
const char *key, unsigned int key_length,
int using_trx);
+void *thd_get_ha_data(const void* thd, const struct handlerton *hton);
+void thd_set_ha_data(const void* thd, const struct handlerton *hton,
+ const void *ha_data);
=== modified file 'sql/handler.cc'
--- a/sql/handler.cc 2009-12-01 09:19:51 +0000
+++ b/sql/handler.cc 2010-03-31 12:04:11 +0000
@@ -601,9 +601,13 @@ static my_bool closecon_handlerton(THD *
there's no need to rollback here as all transactions must
be rolled back already
*/
- if (hton->state == SHOW_OPTION_YES && hton->close_connection &&
- thd_get_ha_data(thd, hton))
- hton->close_connection(hton, thd);
+ if (hton->state == SHOW_OPTION_YES && thd_get_ha_data(thd, hton))
+ {
+ if (hton->close_connection)
+ hton->close_connection(hton, thd);
+ /* make sure ha_data is reset and ha_data_lock is released */
+ thd_set_ha_data(thd, hton, NULL);
+ }
return FALSE;
}
=== modified file 'sql/sql_class.cc'
--- a/sql/sql_class.cc 2010-03-29 02:32:30 +0000
+++ b/sql/sql_class.cc 2010-03-31 12:04:11 +0000
@@ -284,6 +284,36 @@ void **thd_ha_data(const THD *thd, const
return (void **) &thd->ha_data[hton->slot].ha_ptr;
}
+
+/**
+ Provide a handler data getter to simplify coding
+*/
+extern "C"
+void *thd_get_ha_data(const THD *thd, const struct handlerton *hton)
+{
+ return *thd_ha_data(thd, hton);
+}
+
+
+/**
+ Provide a handler data setter to simplify coding
+*/
+extern "C"
+void thd_set_ha_data(const THD *thd, const struct handlerton *hton,
+ const void *ha_data)
+{
+ if (ha_data && !thd->ha_data_lock[hton->slot])
+ ((THD*) thd)->ha_data_lock[hton->slot]=
+ ha_lock_engine(NULL, (handlerton*) hton);
+ else if (!ha_data && thd->ha_data_lock[hton->slot])
+ {
+ plugin_unlock(NULL, thd->ha_data_lock[hton->slot]);
+ ((THD*) thd)->ha_data_lock[hton->slot]= 0;
+ }
+ *thd_ha_data(thd, hton)= (void*) ha_data;
+}
+
+
extern "C"
long long thd_test_options(const THD *thd, long long test_options)
{
@@ -639,6 +669,7 @@ THD::THD()
warn_id= 0;
db_charset= global_system_variables.collation_database;
bzero(ha_data, sizeof(ha_data));
+ bzero(ha_data_lock, sizeof(ha_data_lock));
mysys_var=0;
binlog_evt_union.do_union= FALSE;
enable_slow_log= 0;
=== modified file 'sql/sql_class.h'
--- a/sql/sql_class.h 2010-03-29 02:32:30 +0000
+++ b/sql/sql_class.h 2010-03-31 12:04:11 +0000
@@ -1424,6 +1424,7 @@ public:
/* container for handler's private per-connection data */
Ha_data ha_data[MAX_HA];
+ plugin_ref ha_data_lock[MAX_HA];
#ifndef MYSQL_CLIENT
int binlog_setup_trx_data();
Attachment: [text/bzr-bundle] bzr/svoj@sun.com-20100331120411-u2kmoqnzf5m451t0.bundle
