Re: stmmac / meson8b-dwmac

[Simon Huelck <simonmail@gmx.de>]

Am 17.01.2019 um 21:57 schrieb Martin Blumenstingl:
> Hi Simon,
>
> On Thu, Jan 17, 2019 at 7:53 PM Simon Huelck <simonmail@gmx.de> wrote:
>> Hi Martin,
>>
>>
>> deutsch ?
> theoretisch: ja, das endet bei mir aber in einem komischen Mix aus
> deutsch und englisch, von daher...
>
>> I got problems with my ODROID c2 running on 4.19.16 ( and some releases
>> earlier ). the stmmac / dwmac driver doesnt provide the 800M/900M
>> performance that i was used to earlier.
>>
>>
>> Now im stuck near 550M/600M in the same environment. but what really
>> confuses me that duplex does hurt even more.
> interesting that you see this on the Odroid-C2 as well.
> previously I have only observed it on an Odroid-C1
>
>> PC --- VLAN3 --> switch --VLAN3--> ODROID
>>
>> NAS <-- VLAN1 -- switch <-- VLAN1-- ODROID
>>
>>
>> this means when im doing a iperf from PC to NAS, that my ODROID has load
>> on RX/TX same time (duplex). this shouldnt be an issue , all is 1GBits
>> FD. And in the past that wasnt an issue.
>>
>>
>> Now what happens:
>>
>> - benchmark between PC - ODROID is roughly 550M
>>
>> - benchmark between NAS - ODROID is roughly 550M
>>
>> - benchmark between PC - NAS is only around 300M
>>
>>
>> and like i said i was easliy able to hit 800 or even 900M to my NAS
>> earlier. I applied some .dtb fixes for interrupt levels for the
>> meson-gx.dtsi and meson-gxbb-odroid-c2.dtb, which will be mainlined ,
>> but the effect stayed identical.
> good that you have the interrupt patches already applied
> I believe it don't fix any performance issues - it's a fix for the
> Ethernet controller seemingly getting "stuck" (not processing data
> anymore). however, that already rules out one potential issue
>
>> are you aware of this problem ? Earlier kernel versions were all
>> perfectly fine and i stepped ( self compiled) kernel through all major
>> releases since odroid c2 was mainlined.
> I'm not aware of this - so it would be great if you could re-send your mail to:
> - the mainline Amlogic mailing list at: linux-amlogic@lists.infradead.org
> - the netdev mailing list (where all the networking people discuss
> their issues): netdev@vger.kernel.org
> - the stmmac maintainers: Gpeppe.cavallaro@st.com,
> alexandre.torgue@st.com, joabreu@synopsys.com


ok , will do so

>
> it's great that you stepped through various releases in the past.
> you can even help us to get closer to the root cause of the problem
> using git bisect. in case you haven't used git bisect yet::
> - git bisect start
> - git bisect good v4.18 (assuming v4.18 was good)
> - git bisect bad v4.19 (assuming v4.19 is bad)
> - the repeat the following:
> -- (git will checkout a different revision and ask you to test it)
> -- compile, boot the kernel and test whether your problem still exists
> -- enter either "git bisect good", "git bisect bad" or "git bisect
> skip" (for example if the revision doesn't compile, your board doesn't
> start with it, ...)
>
> git bisect will output one commit which is likely to be the cause (or
> at least a puzzle piece which points to the root cause)


the problem is that i dont have these kernel sources anymore :-(. but i
can provide some testing and numbers. maybe i dig if i got these kernel
configs somewhere around but i did not change much during migrating



im using a zyxel gs1900-8 switch and a qnap ts231p , and as i said i
didnt change my setup. i was able to hit 100MByte/s from my NAS , so
close to the benchmarks of 900MBit/s

>
>
> Regards
> Martin