Re: [RFC PATCH v2 0/8] fprobe: Introduce fprobe function entry/exit probe

Jiri Olsa
2022-01-13T12:27:42Z

On Wed, Jan 12, 2022 at 05:01:15PM +0100, Jiri Olsa wrote:
> On Wed, Jan 12, 2022 at 11:02:46PM +0900, Masami Hiramatsu wrote:
> > Hi Jiri and Alexei,
> >
> > Here is the 2nd version of fprobe. This version uses the
> > ftrace_set_filter_ips() for reducing the registering overhead.
> > Note that this also drops per-probe point private data, which
> > is not used anyway.
> >
> > This introduces the fprobe, the function entry/exit probe with
> > multiple probe point support. This also introduces the rethook
> > for hooking function return as same as kretprobe does. This
>
> nice, I was going through the multi-user-graph support
> and was wondering that this might be a better way
>
> > abstraction will help us to generalize the fgraph tracer,
> > because we can just switch it from rethook in fprobe, depending
> > on the kernel configuration.
> >
> > The patch [1/8] and [7/8] are from your series[1]. Other libbpf
> > patches will not be affected by this change.
>
> I'll try the bpf selftests on top of this

I'm getting crash and stall when running bpf selftests,
the fprobe sample module works fine, I'll check on that

jirka