diff options
Diffstat (limited to 'sql/lock.cc')
| -rw-r--r-- | sql/lock.cc | 16 |
1 files changed, 9 insertions, 7 deletions
diff --git a/sql/lock.cc b/sql/lock.cc index ac689495ca3..0917c143a8a 100644 --- a/sql/lock.cc +++ b/sql/lock.cc @@ -732,15 +732,14 @@ bool lock_global_read_lock(THD *thd) while (protect_against_global_read_lock && !thd->killed) pthread_cond_wait(&COND_refresh, &LOCK_open); waiting_for_read_lock--; - thd->exit_cond(old_message); if (thd->killed) { - (void) pthread_mutex_unlock(&LOCK_open); + thd->exit_cond(old_message); DBUG_RETURN(1); } thd->global_read_lock=1; global_read_lock++; - (void) pthread_mutex_unlock(&LOCK_open); + thd->exit_cond(old_message); } DBUG_RETURN(0); } @@ -761,11 +760,12 @@ void unlock_global_read_lock(THD *thd) bool wait_if_global_read_lock(THD *thd, bool abort_on_refresh) { const char *old_message; - bool result=0; + bool result= 0, need_exit_cond; DBUG_ENTER("wait_if_global_read_lock"); + LINT_INIT(old_message); (void) pthread_mutex_lock(&LOCK_open); - if (global_read_lock) + if (need_exit_cond= (bool)global_read_lock) { if (thd->global_read_lock) // This thread had the read locks { @@ -780,11 +780,13 @@ bool wait_if_global_read_lock(THD *thd, bool abort_on_refresh) (void) pthread_cond_wait(&COND_refresh,&LOCK_open); if (thd->killed) result=1; - thd->exit_cond(old_message); } if (!abort_on_refresh && !result) protect_against_global_read_lock++; - pthread_mutex_unlock(&LOCK_open); + if (unlikely(need_exit_cond)) // global read locks are rare + thd->exit_cond(old_message); + else + pthread_mutex_unlock(&LOCK_open); DBUG_RETURN(result); } |