Re: [PATCH net-next v1] gianfar: Change default HW Tx queue scheduling mode

[David Miller <davem@redhat.com>]

From: Claudiu Manoil <claudiu.manoil@freescale.com>
Date: Mon, 24 Sep 2012 11:39:08 +0300

> This is primarily to address transmission timeout occurrences, when
> multiple H/W Tx queues are being used concurrently. Because in
> the priority scheduling mode the controller does not service the
> Tx queues equally (but in ascending index order), Tx timeouts are
> being triggered rightaway for a basic test with multiple simultaneous
> connections like:
> iperf -c <server_ip> -n 100M -P 8
> 
> resulting in kernel trace:
> NETDEV WATCHDOG: eth1 (fsl-gianfar): transmit queue <X> timed out
> ------------[ cut here ]------------
> WARNING: at net/sched/sch_generic.c:255
> ...
> and controller reset during intense traffic, and possibly further
> complications.
> 
> This patch changes the default H/W Tx scheduling setting (TXSCHED)
> for multi-queue devices, from priority scheduling mode to a weighted
> round robin mode with equal weights for all H/W Tx queues, and
> addresses the issue above.
> 
> Signed-off-by: Claudiu Manoil <claudiu.manoil@freescale.com>

Applied, thanks.