Merge "Revert "Avoid doNotifyQueueEmpty() race conditions for Redis""

diff --combined includes/jobqueue/aggregator/JobQueueAggregatorRedis.php
index 250947a,6c49646..9b4e7e9
--- 1/includes/jobqueue/aggregator/JobQueueAggregatorRedis.php
--- 2/includes/jobqueue/aggregator/JobQueueAggregatorRedis.php
+++ b/includes/jobqueue/aggregator/JobQueueAggregatorRedis.php
@@@ -31,10 -31,9 +31,10 @@@
  class JobQueueAggregatorRedis extends JobQueueAggregator {
        /** @var RedisConnectionPool */
        protected $redisPool;
 -
        /** @var array List of Redis server addresses */
        protected $servers;
 +      /** @var bool */
 +      protected $registeredQueue = false;
  
        /**
         * @param array $params Possible keys:
@@@ -60,11 -59,7 +60,7 @@@
                        return false;
                }
                try {
-                       // Make sure doNotifyQueueNonEmpty() takes precedence to avoid races
-                       $conn->watch( $this->getReadyQueueKey() );
-                       $conn->multi()
-                               ->hDel( $this->getReadyQueueKey(), $this->encQueueName( $type, $wiki ) )
-                               ->exec();
+                       $conn->hDel( $this->getReadyQueueKey(), $this->encQueueName( $type, $wiki ) );
  
                        return true;
                } catch ( RedisException $e ) {
@@@ -81,16 -76,11 +77,16 @@@
                }
                try {
                        $conn->multi( Redis::PIPELINE );
 -                      $conn->hSetNx( $this->getQueueTypesKey(), $type, 'enabled' );
 -                      $conn->sAdd( $this->getWikiSetKey(), $wiki );
 +                      if ( !$this->registeredQueue ) {
 +                              // Make sure the queue is registered as existing
 +                              $conn->hSetNx( $this->getQueueTypesKey(), $type, 'enabled' );
 +                              $conn->sAdd( $this->getWikiSetKey(), $wiki );
 +                      }
                        $conn->hSet( $this->getReadyQueueKey(), $this->encQueueName( $type, $wiki ), time() );
                        $conn->exec();
  
 +                      $this->registeredQueue = true;
 +
                        return true;
                } catch ( RedisException $e ) {
                        $this->handleException( $conn, $e );