net_sched: reintroduce dev->qdisc for use by sch_api
Currently the multiqueue integration with the qdisc API suffers from
a few problems:
- with multiple queues, all root qdiscs use the same handle. This means
they can't be exposed to userspace in a backwards compatible fashion.
- all API operations always refer to queue number 0. Newly created
qdiscs are automatically shared between all queues, its not possible
to address individual queues or restore multiqueue behaviour once a
shared qdisc has been attached.
- Dumps only contain the root qdisc of queue 0, in case of non-shared
qdiscs this means the statistics are incomplete.
This patch reintroduces dev->qdisc, which points to the (single) root qdisc
from userspace's point of view. Currently it either points to the first
(non-shared) default qdisc, or a qdisc shared between all queues. The
following patches will introduce a classful dummy qdisc, which will be used
as root qdisc and contain the per-queue qdiscs as children.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 121cbad..a44118b 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -832,6 +832,9 @@
/* Number of TX queues currently active in device */
unsigned int real_num_tx_queues;
+ /* root qdisc from userspace point of view */
+ struct Qdisc *qdisc;
+
unsigned long tx_queue_len; /* Max frames per queue allowed */
spinlock_t tx_global_lock;
/*