Bug #26588738 : MEMCACHED.MEMC280_MISC FAILS WITH SIG 11 ON PB2

Background:
  memcached plugin listens to a specific (hardocded) port in MTR tests.
  Therefore when a testcase is executed in parallel to itself, it might fail with
  an error that port is in use. Which is expected. And then memcached plugin code
  goes for a cleanup.

Issue:
  In memcached code, my_thread_init() was taken out from handler_create_thd().
  Thus, during cleanup, when handler_create_thd() is called, it crashes (as thd
  is not initialized and THR_mysys is NULL).
  It was not failing in MySQL 5.7 because in 5.7, my_thread_init() was inside
  handler_create_thd().

Fix:
  Before calling handler_create_thd(), make sure to call my_thread_init(), to
  initialized thread.

  Reviewed by: [email protected]
  RB: 17547

Author: mayprasa

plugin/innodb_memcached/innodb_memcache/src/innodb_engine.c

@@ -786,6 +786,7 @@ innodb_conn_clean(
 	void*			thd = NULL;
 
 	if (clear_all) {
+		my_thread_init();
 		thd = handler_create_thd(engine->enable_binlog);
 	}
 
@@ -859,6 +860,7 @@ innodb_conn_clean(
 	if (thd) {
 		handler_thd_attach(thd, NULL);
 		handler_close_thd(thd);
+		my_thread_end();
 	}
 
 	return(num_freed);