BUG#29968 (rpl_ndb_circular.test and rpl_ndb_log.test fail):

Removing unguarded read of slave_running field from inside
terminate_slave_threads(). This could cause premature exit in the event
that the slave thread already were shutting down, but isn't finished yet.

The fields slave_running, io_thd, and sql_thread are guarded by an
associated run_lock. A read of these fields were not guarded inside
terminate_slave_threads(), which caused an assertion to fire. The
assertion was removed, and the code reorganized slightly.


sql/slave.cc:
  Changing signature of terminate_slave_thread() to accept a skip_lock
  parameter instead of two mutexes. This mimics the signature of the
  terminate_slave_threads() function. Code is also changed as a result
  of this.
  
  Removing unguarded check of slave_running field in the master info and
  relay log info structure since that could cause premature exit of
  terminate_slave_threads().
  
  The thread variable for each of the slave threads can change before
  acquiring the run_lock mutex inside terminate_slave_thread(). Hence
  an assertion was removed that read the variable without guarding it
  with run_lock.
  
  Code that checked *slave_running status inside terminate_slave_thread()
  was reorganized slightly.
sql/slave.h:
  Moving terminate_slave_thread() to use internal linkage.

1 files changed, 0 insertions, 4 deletions

diff --git a/sql/slave.h b/sql/slave.h
index 731728bde4f..c7385934460 100644
--- a/sql/slave.h
+++ b/sql/slave.h
@@ -133,10 +133,6 @@ bool flush_relay_log_info(RELAY_LOG_INFO* rli);
 int register_slave_on_master(MYSQL* mysql);
 int terminate_slave_threads(MASTER_INFO* mi, int thread_mask,
 			     bool skip_lock = 0);
-int terminate_slave_thread(THD* thd, pthread_mutex_t* term_mutex,
-			   pthread_mutex_t* cond_lock,
-			   pthread_cond_t* term_cond,
-			   volatile uint* slave_running);
 int start_slave_threads(bool need_slave_mutex, bool wait_for_start,
 			MASTER_INFO* mi, const char* master_info_fname,
 			const char* slave_info_fname, int thread_mask);