linux/drivers/s390
Julian Wiedmann 3a18d75400 s390/qeth: add TX multiqueue support for IQD devices
qeth has been supporting multiple HW Output Queues for a long time. But
rather than exposing those queues to the stack, it uses its own queue
selection logic in .ndo_start_xmit... with all the drawbacks that
entails.
Start off by switching IQD devices over to a proper mqs net_device,
and converting all the netdev_queue management code.

One oddity with IQD devices is the requirement to place all mcast
traffic on the _highest_ established HW queue. Doing so via
.ndo_select_queue seems straight-forward - but that won't work if only
some of the HW queues are active
(ie. when dev->real_num_tx_queues < dev->num_tx_queues), since
netdev_cap_txqueue() will not allow us to put skbs on the higher queues.

To make this work, we
1. let .ndo_select_queue() map all mcast traffic to netdev_queue 0, and
2. later re-map the netdev_queue and HW queue indices in
   .ndo_start_xmit and the TX completion handler.

With this patch we default to a fixed set of 1 ucast and 1 mcast queue.
Support for dynamic reconfiguration is added at a later time.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-17 10:33:59 -07:00
..
block s390 updates for the 5.1 merge window 2019-03-05 11:13:10 -08:00
char s390 updates for the 5.1 merge window 2019-03-05 11:13:10 -08:00
cio s390 update with improvements and bug fixes for 5.1-rc2 2019-03-28 08:35:32 -07:00
crypto zcrypt: handle AP Info notification from CHSC SEI command 2019-03-11 10:16:42 -07:00
net s390/qeth: add TX multiqueue support for IQD devices 2019-04-17 10:33:59 -07:00
scsi scsi: zfcp: reduce flood of fcrscn1 trace records on multi-element RSCN 2019-03-27 21:26:12 -04:00
virtio virtio-ccw: wire up ->bus_name callback 2019-03-06 11:19:56 -05:00
Makefile kbuild: rename built-in.o to built-in.a 2018-03-26 02:01:19 +09:00