Re: [PATCH v3 perf, bpf-next 1/4] perf, bpf: Introduce PERF_RECORD_BPF_EVENT

[Peter Zijlstra]

On Wed, Dec 12, 2018 at 05:09:17PM +0000, Song Liu wrote:
> > And while this tracks the bpf kallsyms, it does not do all kallsyms.
> > 
> > .... Oooh, I see the problem, everybody is doing their own custom
> > kallsym_{add,del}() thing, instead of having that in generic code :-(
> > 
> > This, for example, doesn't track module load/unload nor ftrace
> > trampolines, even though both affect kallsyms.
> 
> I think we can use PERF_RECORD_MMAP(or MMAP2) for module load/unload. 
> That could be separate sets of patches. 

So I would actually like to move bpf_lock/bpf_kallsyms/bpf_tree +
bpf_prog_kallsyms_*() + __bpf_address_lookup() into kernel/kallsyms.c
and also have ftrace use that.

Because currently the ftrace stuff is otherwise invisible.

A generic kallsym register/unregister for any JIT.