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    SubjectRe: [RFC] ftrace: Add support to keep some functions out of ftrace
    On Mon, Aug 15, 2022 at 11:44:32AM +0200, Jiri Olsa wrote:
    > On Mon, Aug 15, 2022 at 10:03:17AM +0200, Peter Zijlstra wrote:
    > > On Sat, Aug 13, 2022 at 03:02:52PM -0400, Steven Rostedt wrote:
    > > > On Fri, 12 Aug 2022 23:18:15 +0200
    > > > Jiri Olsa <olsajiri@gmail.com> wrote:
    > > >
    > > > > the patch below moves the bpf function into sepatate object and switches
    > > > > off the -mrecord-mcount for it.. so the function gets profile call
    > > > > generated but it's not visible to ftrace
    > >
    > > Why ?!?
    >
    > there's bpf dispatcher code that updates bpf_dispatcher_xdp_func
    > function with bpf_arch_text_poke and that can race with ftrace update
    > if the function is traced

    I thought bpf_arch_text_poke() wasn't allowed to touch kernel code and
    ftrace is in full control of it ?

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