Comment 53 for bug 709245

On Fri, Jul 6, 2012 at 6:57 AM, Emeric Vigier <email address hidden> wrote:
> Hi,
>
> I am having ethernet performance issue on panda rev A3. TX gets stuck while RX seems fine. At least pinging is ok...

We are discussing a similar problem now, see below link:

            http://marc.info/?t=134145311800001&r=1&w=2

I found that enabling DEBUG_SLAB may degrade TX performance a lot( ~35Mbps).
But if the option is disabled, the TX performance should be OK(> 90Mbps).

I am not sure if it is same with your problem.

> I started a thread on various mailing-list (http://comments.gmane.org/gmane.linux.network/234335).
> I made a lot of trials but no luck so far...
>
> My problem may be related to the one described here for usb storage. My
> kernel already embeds Ming Lei's patch
> (https://patchwork.kernel.org/patch/1113332/), and
> CONFIG_ARM_DMA_MEM_BUFFERABLE and CONFIG_ARCH_HAS_BARRIERS are enabled.
> But still ethernet performance is really poor.
>
> Smsc9514 device driver relies on usbnet. I lack usb knowledge, thus I
> cannot state whether Ming Lei's patch in ehci-q.c "should" fix my issue

> if they were related. Otherwise, did anyone find out that
> CONFIG_PL310_ERRATA_769419 patch above effectively fixes the usb storage
> issue?

Yes, it is fine for the problem, so the ehci patch isn't needed to upstream.

Thanks,
--
Ming Lei