Messages in this thread | | | From | Song Liu <> | Subject | Re: [PATCH v3 perf, bpf-next 1/4] perf, bpf: Introduce PERF_RECORD_BPF_EVENT | Date | Wed, 12 Dec 2018 18:56:11 +0000 |
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> On Dec 12, 2018, at 10:05 AM, Peter Zijlstra <peterz@infradead.org> wrote: > > 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.
I guess this is _not_ a requirement for this patchset? BPF program has special data (id, sub_id, tag) that we need PERF_RECORD_BPF_EVENT. So this patchset should be orthogonal to the generic kallsym framework?
Thanks, Song
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