Re: [dpdk-dev] [PATCH] crypto/armv8: enable meson build

[Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>]

On Sat, 12 Oct, 2019, 12:44 AM Honnappa Nagarahalli, <Honnappa.Nagarahalli@arm.com<mailto:Honnappa.Nagarahalli@arm.com>> wrote:
<snip>

On Thu, 10 Oct, 2019, 10:17 AM Honnappa Nagarahalli, <Honnappa.Nagarahalli@arm.com<mailto:Honnappa.Nagarahalli@arm.com>> wrote:
<snip>

On Mon, 7 Oct, 2019, 3:49 PM Jerin Jacob, <jerinjacobk@gmail.com<mailto:jerinjacobk@gmail.com>> wrote:

On Sun, 6 Oct, 2019, 11:36 PM Thomas Monjalon, <thomas@monjalon.net<mailto:thomas@monjalon.net>> wrote:
05/10/2019 17:28, Jerin Jacob:
> On Fri, Oct 4, 2019 at 4:27 AM Dharmik Thakkar <dharmik.thakkar@arm.com<mailto:dharmik.thakkar@arm.com>> wrote:
> >
> > Add new meson.build file for crypto/armv8
> >
> > Signed-off-by: Dharmik Thakkar <dharmik.thakkar@arm.com<mailto:dharmik.thakkar@arm.com>>
> > ---
> >  drivers/crypto/armv8/meson.build | 25 +++++++++++++++++++++++++
> >  drivers/crypto/meson.build       |  6 +++---
> >  meson_options.txt                |  2 ++
> >  3 files changed, 30 insertions(+), 3 deletions(-)
> >  create mode 100644 drivers/crypto/armv8/meson.build
>
> >
> >  option('allow_invalid_socket_id', type: 'boolean', value: false,
> >         description: 'allow out-of-range NUMA socket id\'s for platforms that don\'t report the value correctly')
> > +option('armv8_crypto_dir', type: 'string', value: '',
> > +       description: 'path to the armv8_crypto library installation directory')

You should not need such option if you provide a pkg-config file
in your library.


> It is not specific to this patch but it is connected to this patch.
>
> Three years back when Cavium contributed to this driver the situation
> was different where only Cavium was contributing to DPDK and now we
> have multiple vendors from
> ARMv8 platform and ARM itself is contributing it.
>
> When it is submitted, I was not in favor of the external library. But
> various reasons it happened to be the external library where 90% meat
> in this library and shim PMD
> the driver moved to DPDK.
>
> Now, I look back, It does not make sense to the external library. Reasons are
> - It won't allow another ARMv8 player to contribute to this library as
> Marvell owns this repo and there is no upstreaming path to this
> library.

This is a real issue and you are able to fix it.

Note sure how I can fix it and why I need to fix it. I just dont want to start a parallel collaborating infrastructure for DPDK armv8.



> - That made this library to not have 'any' change for the last three
> year and everyone have there owned copy of this driver. In fact the
> library was not compiling for last 2.5 years.
> - AES-NI case it makes sense to have an external library as it is a
> single vendor and it is not specific to DPDK. But in this, It is
> another way around

I don't see how it is different, except it is badly maintained.

It is different because only one company contributing to it. In this case, multiple companies needs to contribute.

The library badly maintained in upstream as there is no incentives to upstream  to external library. I believe each vendor has it own copy of that. At least Some teams in Marvell internally has copy of it.
What is their incentive to upstream? They ask me the same thing.



> - If it an external library, we might as well add the PMD code as well
> there and that only 10% of the real stuff.
> We are not able able to improve anything in this library due to this situation.
>
> Does anyone care about this PMD? If not, we might as well remove this
> DPDK and every vendor can manage the external library and external
> PMD(Situation won't change much)

External PMD is bad.

It is SHIM layer. I would say external library also bad if it is specific to DPDK.

I think this library should not be specific to DPDK,

Sadly it is VERY specific to DPDK for doing authentication and encryption in one shot to improve the performance. Openssl has already has armv8 instructions support for doing it as two pass just that performance is not good. For use cae such as  IPsec it make sense do authentication and encryption in one shot for performance improvement.
[Honnappa] I think there is a need for such a library not just for DPDK. It would be good if it could do UDP checksum validation for the inner packet as well.

so it would make sense as an external library

If it an external library, it does NOT make  much sense for Marvell to maintain it(No incentive and it is pain due lack of collaboration)

Either someone need to step up and maintain it if we NOT choose to make it as external else we can remove the PMD from dpdk(Makes life easy for everyone). I don't want to maintain something not upsteamble nor collaboration friendly aka less quality.

.




> Thoughts from ARM, other ARMv8 vendors or community?

I have expressed my concerns. If there is no constructive feedback to fix the concern. I will plan for submitting a patch to remove the shim crypto Armv8 PMD from dpdk by next week.
[Honnappa] I do not think there is a need to remove the PMD. As you have mentioned, many might have developed their own libraries and may be dependent on DPDK Armv8 PMD.

Problem with that approach is that, No convergence/collaboration on this PMD aka no improvement and less quality.
[Honnappa] Would not removing this fall under ABI/API compatibility? Essentially, DPDK defines how an external Armv8 Crypto library can work with DPDK. Is it possible to remove it considering that there might be users dependent on this?
I agree with you on the improvements (features?), but not sure on quality. For the features that are supported, the quality should be good.

The library was broken for last 2.5 years. Is that the high quality and no improvement for last 3 year and no single contribution otherthan Marvell in external library.
[Honnappa] We need to separate the discussion about PMD and the external library. IMO, PMD cannot be removed as some might be using the interfaces with their own crypto library.

From Arm side, there have been efforts to fix the situation. Some have not gone far and some have shown promise, but fell flat. I can say that this is still a priority but I am not sure when we will have something.

If ARM is ready to take over the maintenance on PMD and external library then I am fine with any decision.
Let us know. Personally, I don't like to maintain something not upsteamble friendly.
[Honnappa] What is the maintenance burden on the PMD? Can you elaborate?

Marvell open-source policy is bit different than cavium policy. We can not contribute to GitHub repository with out approval. The existing external library, not belongs to Marvell GitHub domain. I need to create a case to add new GitHub repo under Marvell to contribute to all armv8 partners. I don't have justification for that to legal. We have approvals to contribute to dpdk.org<http://dpdk.org>

On the external library, I do not think this is the right forum to make a decision. There are channels provided to all our partners to discuss these kind of topics and I think those should be made use of.
It is cavium created library for dpdk. Why we need to discuss in some other channel. I believe this is the correct forum for dpdk discussions.
[Honnappa] May be I was not clear, please see my comment below.

For example, Dharmik got comment to update the external library to support autoconfig for meson. What is the path for Dharmik to do that?
[Honnappa] Is this mainly from testing purposes?

Don't you think, you need have access to the complete code base to contribute. That's the reason why I am saying remove the external library and have it in DPDK so that everyone can contribute and improve.
[Honnappa] I don’t have any issues

If you think, otherwise please take over the maintenance keeping initial author credit. If you need time to take decision that makes sense. You can share the ETA. Otherwise, this discussion going in circles.
[Honnappa] This cannot be decided in this forum.


My suggestion, we should go ahead with adding the meson build for this PMD.