cfq-iosched: make io priorities inherit CPU scheduling class as well as nice

We currently set all processes to the best-effort scheduling class,
regardless of what CPU scheduling class they belong to. Improve that
so that we correctly track idle and rt scheduling classes as well.

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

1 files changed, 2 insertions, 2 deletions

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 7f909d2f4886..b399c62936e0 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -1303,10 +1303,10 @@ static void cfq_init_prio_data(struct cfq_queue *cfqq, struct io_context *ioc)
                 printk(KERN_ERR "cfq: bad prio %x\n", ioprio_class);
         case IOPRIO_CLASS_NONE:
                 /*
-                 * no prio set, place us in the middle of the BE classes
+                 * no prio set, inherit CPU scheduling settings
                  */
                 cfqq->ioprio = task_nice_ioprio(tsk);
-                cfqq->ioprio_class = IOPRIO_CLASS_BE;
+                cfqq->ioprio_class = task_nice_ioclass(tsk);
                 break;
         case IOPRIO_CLASS_RT:
                 cfqq->ioprio = task_ioprio(ioc);