cfq-iosched: never allow an async queue idling

We don't enable it by default, don't let it get enabled during
runtime.

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

1 files changed, 6 insertions, 1 deletions

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 839086dcb0af..df82755ac40b 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -1603,7 +1603,12 @@ static void
 cfq_update_idle_window(struct cfq_data *cfqd, struct cfq_queue *cfqq,
                        struct cfq_io_context *cic)
 {
-        int enable_idle = cfq_cfqq_idle_window(cfqq);
+        int enable_idle;
+
+        if (!cfq_cfqq_sync(cfqq))
+                return;
+
+        enable_idle = cfq_cfqq_idle_window(cfqq);
 
         if (!cic->ioc->task || !cfqd->cfq_slice_idle ||
             (cfqd->hw_tag && CIC_SEEKY(cic)))