Re: [PATCH bpf-next v3 1/3] xsk: Support UMEM chunk_size > PAGE_SIZE

From: Toke Høiland-Jørgensen
Date: Thu Apr 13 2023 - 18:29:56 EST


Kal Cutter Conley <kal.conley@xxxxxxxxxxx> writes:

>> "More annoying" is not a great argument, though. You're basically saying
>> "please complicate your code so I don't have to complicate mine". And
>> since kernel API is essentially frozen forever, adding more of them
>> carries a pretty high cost, which is why kernel developers tend not to
>> be easily swayed by convenience arguments (if all you want is a more
>> convenient API, just build one on top of the kernel primitives and wrap
>> it into a library).
>
> I was trying to make a fair comparison from the user's perspective
> between having to allocate huge pages and deal with discontiguous
> buffers. That was all.
>
> I think the "your code" distinction is a bit harsh. The kernel is a
> community project. Why isn't it "our" code? I am trying to add a
> feature that I think is generally useful to people. The kernel only
> exists to serve its users.

Oh, I'm sorry if that came across as harsh, that was not my intention! I
was certainly not trying to make a "you vs us" distinction; I was just
trying to explain why making changes on the kernel side carries a higher
cost than an equivalent (or even slightly more complex) change on the
userspace side, because of the UAPI consideration.

> I believe I am doing more good than harm sending these patches.

I don't think so! You've certainly sparked a discussion, that is good :)

-Toke