drbd: explicitly submit meta data requests with REQ_NOIDLE
authorLars Ellenberg <lars.ellenberg@linbit.com>
Tue, 11 Feb 2014 07:56:53 +0000 (08:56 +0100)
committerPhilipp Reisner <philipp.reisner@linbit.com>
Thu, 10 Jul 2014 16:34:54 +0000 (18:34 +0200)
For some reason we have assumed NOIDLE was implied
by one of the other flags we set. It is not (anymore?).
Explicitly set REQ_NOIDLE for synchronous meta data updates,
or we can seriously starve random writes when using CFQ.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
drivers/block/drbd/drbd_actlog.c

index 278c31f246398b6d4de715dd9884d0601abc26f8..14b2f27291aa05b35b8e81de37cd350e65f71a7c 100644 (file)
@@ -150,7 +150,7 @@ static int _drbd_md_sync_page_io(struct drbd_device *device,
 
        if ((rw & WRITE) && !test_bit(MD_NO_FUA, &device->flags))
                rw |= REQ_FUA | REQ_FLUSH;
-       rw |= REQ_SYNC;
+       rw |= REQ_SYNC | REQ_NOIDLE;
 
        bio = bio_alloc_drbd(GFP_NOIO);
        bio->bi_bdev = bdev->md_bdev;