USB: uas: Fix slave queue_depth not being set
authorHans de Goede <hdegoede@redhat.com>
Tue, 31 May 2016 07:18:03 +0000 (09:18 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 1 Jun 2016 21:56:24 +0000 (14:56 -0700)
Commit 198de51dbc34 ("USB: uas: Limit qdepth at the scsi-host level")
removed the scsi_change_queue_depth() call from uas_slave_configure()
assuming that the slave would inherit the host's queue_depth, which
that commit sets to the same value.

This is incorrect, without the scsi_change_queue_depth() call the slave's
queue_depth defaults to 1, introducing a performance regression.

This commit restores the call, fixing the performance regression.

Cc: stable@vger.kernel.org
Fixes: 198de51dbc34 ("USB: uas: Limit qdepth at the scsi-host level")
Reported-by: Tom Yan <tom.ty89@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/storage/uas.c

index e03c490616ef3f40218159ef4aaa5833df9048f5..5ef014ba6ae86917f34e6ebbd855845e3bf71732 100644 (file)
@@ -836,6 +836,7 @@ static int uas_slave_configure(struct scsi_device *sdev)
        if (devinfo->flags & US_FL_BROKEN_FUA)
                sdev->broken_fua = 1;
 
+       scsi_change_queue_depth(sdev, devinfo->qdepth - 2);
        return 0;
 }