[PATCH] ipw2200: stop netdev queue if h/w doesn't have space for new packets
authorJames Ketrenos <jketreno@linux.intel.com>
Tue, 14 Feb 2006 01:10:51 +0000 (09:10 +0800)
committerJohn W. Linville <linville@tuxdriver.com>
Fri, 17 Mar 2006 20:08:02 +0000 (15:08 -0500)
commitf697014af90c1db3c7b299327bf5a9548945b8bf
tree983fd3e7a6c3c365a78f9d79cfdfd5761b60c7ea
parent48a847709f821b5eecd45ae7660add1869f9cd37
[PATCH] ipw2200: stop netdev queue if h/w doesn't have space for new packets

The patch roll back the change we made to support for the ability to
start/stop independent Tx queues within a single net device in order to
support 802.11e QoS. We need to be able to indicate to the upper layers
that packets of a given priority can not be sent any more without halting
transmission of all packets, and without rescheduling high priority packets
down to the next priority level.

So we return NETDEV_TX_BUSY in this case and rely on the stack would
take care of rescheduling... which it apparently does immediately and
consumes the CPU. This caused the ksoftirqd kernel thread consuming almost
all the CPU...

To put the code back to the way it was before we made these changes we
put the call netif_queue_stop back in ipw_tx_skb.  This effectively
disables multiple priority based transmit queues for 802.11e, but given
that its broken anyway...

Signed-off-by: James Ketrenos <jketreno@linux.intel.com>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
drivers/net/wireless/ipw2200.c