Method wakeup

sql/sql_class.cc:8465–8491

void
wait_for_commit::wakeup(int wakeup_error)
{
  /*
    We signal each waiter on their own condition and mutex (rather than using
    pthread_cond_broadcast() or something like that).

    Otherwise we would need to somehow ensure that they were done
    waking up before we could allow this THD to be destroyed, which would
    be annoying and unnecessary.

    Note that wakeup_subsequent_commits2() depends on this function being a
    full memory barrier (it is, because it takes a mutex lock).

  */
  mysql_mutex_lock(&LOCK_wait_commit);
  this->wakeup_error= wakeup_error;
  /* Memory barrier to make wakeup_error visible to the waiter thread. */
  waitee.store(NULL, std::memory_order_release);
  /*
    Note that it is critical that the mysql_cond_signal() here is done while
    still holding the mutex. As soon as we release the mutex, the waiter might
    deallocate the condition object.
  */
  mysql_cond_signal(&COND_wait_commit);
  mysql_mutex_unlock(&LOCK_wait_commit);
}


/*