On 10/8/19 10:24 AM, Kurt Van Dijck wrote:
>>>> taking up Kurt's work. I've cleaned up the rx-offload and c_can patches
>>>> a bit. Untested as I don't have any hardware at hand.
>>>
>>> I had created equivalent code (skb_queue in isr, skb_dequeue in napi
>>> handler) running on a 4.9 kernel since some days now. I didn't observe
>>> any problems yet.
>>
>> This is based on the patches you send around.
>> Anyways can you send me your currently working version?
>
> I know. My first attempt was to backport rx-offload, but this was more
> work than expected, so I created this patch, doing the skb_queue inside
> c_can driver directly. I wrote that patch with the latest rx-offload.c
> side-by-side.
>
> I just wrote it this way quickly so I could go ahead and test the mower,
> upgrading to a more recent kernel is scheduled within a few months or
> so.
Ok, so which variant should be integrated into the kernel?
> From ba7d83f7e8c6a70fc4593cd069b27d6bbe0c5b8e Mon Sep 17 00:00:00 2001
> From: Kurt Van Dijck <dev.kurt@xxxxxxxxxxxxxxxxxxxxxx>
> Date: Sat, 5 Oct 2019 22:43:53 +0200
> Subject: [PATCH 22/23] c_can: use fifo
>
> Avoid softirq latency by reading the CAN msgs in the irq handler,
> and push the msgs in a FIFO.
> The napi handler will empty the FIFO in softirq.
>
> This commit also avoids missed CAN status interrupts,
> INT_REG is only read once per interrupt.
I'd like to fix the problem first, before moving the driver to
rx-offload or this variant.
So I'll take:
[PATCH 1/3] net can c_can: only read status register after
status irq
on top of Jeroen Hofstee's patches.
Marc
--
Pengutronix e.K. | Marc Kleine-Budde |
Industrial Linux Solutions | Phone: +49-231-2826-924 |
Vertretung West/Dortmund | Fax: +49-5121-206917-5555 |
Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de |
Attachment:
signature.asc
Description: OpenPGP digital signature
