Merge lp:~laurynas-biveinis/percona-server/bug1397859 into lp:percona-server/5.6

[Laurynas Biveinis]

Fix bug 1397859 (5.6 with enabled HandlerSocket hangs on shutdown).

There are two issues. First, dbcontex::term_thread calls
remove_global_thread with LOCK_thread_count locked, which is incorrect
after the fix for http://bugs.mysql.com/bug.php?id=69954, which makes
remove_global_thread to take that mutex. Fix by taking the mutex
conditionally in HandlerSocket.

Second, remove_global_thread fails with the debug assert that
thd->release_resources() has not been called yet. This function is
supposed to perform a part of THD::~THD destruction outside
LOCK_thread_count protection, so call it accordingly.

Add a testcase and support for testing HandlerSocket in MTR.

http://jenkins.percona.com/job/percona-server-5.6-param/763/

[Laurynas Biveinis (laurynas-biveinis)]

ST 48431

[George Ormond Lorch III (gl-az)]

review: Approve (g2)

=== added file 'mysql-test/include/have_handler_socket.inc'
--- mysql-test/include/have_handler_socket.inc	1970-01-01 00:00:00 +0000
+++ mysql-test/include/have_handler_socket.inc	2014-12-01 16:32:28 +0000
@@ -0,0 +1,15 @@
+if (`SELECT @@have_dynamic_loading != 'YES'`) {
+  --skip HandlerSocket plugin requires dynamic loading
+}
+
+if (!$HANDLER_SOCKET) {
+  --skip HandlerSocket plugin requires the environment variable $HANDLER_SOCKET to be set (normally done by MTR)
+}
+
+#
+# Check if --plugin-dir was setup for HandlerSocket
+#
+if (`SELECT CONCAT('--plugin-dir=', REPLACE(@@plugin_dir, '\\\\', '/')) != '$HANDLER_SOCKET_OPT/'`) {
+  --skip HandlerSocket plugin requires that --plugin-dir is set to the plugin dir (either the .opt file does not contain $HANDLER_SOCKET_OPT or another plugin is in use)
+}
+enable_query_log;
 
=== modified file 'mysql-test/include/plugin.defs'
--- mysql-test/include/plugin.defs	2014-12-01 07:53:48 +0000
+++ mysql-test/include/plugin.defs	2014-12-01 16:32:28 +0000
@@ -50,3 +50,4 @@
 adt_null           plugin/audit_null  AUDIT_NULL
 audit_log          plugin/audit_log   AUDIT_LOG             audit_log
 query_response_time plugin/query_response_time PLUGIN_QUERY_RESPONSE_TIME QUERY_RESPONSE_TIME_AUDIT,QUERY_RESPONSE_TIME 
+handlersocket      plugin/HandlerSocket-Plugin-for-MySQL HANDLER_SOCKET
 
=== added file 'mysql-test/r/handler_socket.result'
--- mysql-test/r/handler_socket.result	1970-01-01 00:00:00 +0000
+++ mysql-test/r/handler_socket.result	2014-12-01 16:32:28 +0000
@@ -0,0 +1,4 @@
+call mtr.add_suppression("handlersocket: open_files_limit is too small");
+INSTALL PLUGIN handlersocket SONAME 'HANDLER_SOCKET';
+Restarting mysqld for bug 1397859 test...
+UNINSTALL PLUGIN handlersocket;
 
=== added file 'mysql-test/t/handler_socket-master.opt'
--- mysql-test/t/handler_socket-master.opt	1970-01-01 00:00:00 +0000
+++ mysql-test/t/handler_socket-master.opt	2014-12-01 16:32:28 +0000
@@ -0,0 +1,1 @@
+$HANDLER_SOCKET_OPT --loose-handlersocket-port=9998
 
=== added file 'mysql-test/t/handler_socket.test'
--- mysql-test/t/handler_socket.test	1970-01-01 00:00:00 +0000
+++ mysql-test/t/handler_socket.test	2014-12-01 16:32:28 +0000
@@ -0,0 +1,14 @@
+--source include/have_handler_socket.inc
+
+call mtr.add_suppression("handlersocket: open_files_limit is too small");
+
+--replace_result $HANDLER_SOCKET HANDLER_SOCKET
+eval INSTALL PLUGIN handlersocket SONAME '$HANDLER_SOCKET';
+
+#
+# Test for bug 1397859: mysqld crashes or hangs on HS plugin shutdown
+#
+--echo Restarting mysqld for bug 1397859 test...
+--source include/restart_mysqld.inc
+
+UNINSTALL PLUGIN handlersocket;
 
=== modified file 'plugin/HandlerSocket-Plugin-for-MySQL/handlersocket/database.cpp'
--- plugin/HandlerSocket-Plugin-for-MySQL/handlersocket/database.cpp	2014-05-26 07:38:54 +0000
+++ plugin/HandlerSocket-Plugin-for-MySQL/handlersocket/database.cpp	2014-12-01 16:32:28 +0000
@@ -351,7 +351,12 @@
   unlock_tables_if();
   my_pthread_setspecific_ptr(THR_THD, 0);
   {
+    #if MYSQL_VERSION_ID >= 50600
+    thd->release_resources();
+    #endif
+    #if MYSQL_VERSION_ID < 50620
     pthread_mutex_lock(&LOCK_thread_count);
+    #endif
     #if MYSQL_VERSION_ID >= 50600
     remove_global_thread(thd);
     #else
@@ -359,7 +364,9 @@
     #endif
     delete thd;
     thd = 0;
+    #if MYSQL_VERSION_ID < 50620
     pthread_mutex_unlock(&LOCK_thread_count);
+    #endif
     my_thread_end();
   }
 }