Messages in this thread | | | Date | Mon, 15 Aug 2022 14:37:38 +0200 | From | Peter Zijlstra <> | Subject | Re: [RFC] ftrace: Add support to keep some functions out of ftrace |
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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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