Re: [PATCH v1 2/8] tracing/ftrace: guard syscall probe with preempt_notrace

From: Steven Rostedt
Date: Fri Oct 04 2024 - 10:57:46 EST


On Fri, 4 Oct 2024 10:19:36 -0400
Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx> wrote:

> The eBPF people want to leverage this. When I last discussed this with
> eBPF maintainers, they were open to adapt eBPF after this infrastructure
> series is merged. Based on this eBPF attempt from 2022:
>
> https://lore.kernel.org/lkml/c323bce9-a04e-b1c3-580a-783fde259d60@xxxxxx/

Sorry, I wasn't part of that discussion.

>
> The sframe code is just getting in shape (2024), but is far from being ready.
>
> Everyone appears to be waiting for this infrastructure work to go in
> before they can build on top. Once this infrastructure is available,
> multiple groups can start working on introducing use of this into their
> own code in parallel.
>
> Four years into this effort, and this is the first time we're told we need
> to adapt in-tree tracers to handle the page faults before this can go in.
>
> Could you please stop moving the goal posts ?

I don't think I'm moving the goal posts. I was mentioning to show an
in-tree user. If BPF wants this, I'm all for it. The only thing I saw was a
generalization in the cover letter about perf, bpf and ftrace using
faultible tracepoints. I just wanted to see a path for that happening.

-- Steve