NULL engine: ->commit() has side effects, make sure it always works

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

diff --git a/engines/null.c b/engines/null.c
index acb8cf4170c4e00de963f55bae736250a37109da..86b9cbd3929e286a36c098c65cd36278e84c794c 100644 (file)
--- a/engines/null.c
+++ b/engines/null.c
@@ -45,8 +45,11 @@ static int fio_null_commit(struct thread_data *td)
 {
        struct null_data *nd = td->io_ops->data;
 
 {
        struct null_data *nd = td->io_ops->data;
 

-       nd->events += nd->queued;
-       nd->queued = 0;
+       if (!nd->events) {
+               nd->events = nd->queued;
+               nd->queued = 0;
+       }
+

        return 0;
 }
 
        return 0;
 }
 


@@ -56,6 +59,8 @@ static int fio_null_queue(struct thread_data fio_unused *td, struct io_u *io_u)
 
        if (td->io_ops->flags & FIO_SYNCIO)
                return FIO_Q_COMPLETED;
 
        if (td->io_ops->flags & FIO_SYNCIO)
                return FIO_Q_COMPLETED;

+       if (nd->events)
+               return FIO_Q_BUSY;

 
        nd->io_us[nd->queued++] = io_u;
        return FIO_Q_QUEUED;
 
        nd->io_us[nd->queued++] = io_u;
        return FIO_Q_QUEUED;