Messages in this thread | | | Date | Fri, 29 Mar 2024 08:43:13 +0100 | From | Ingo Molnar <> | Subject | Re: [PATCH v2] perf/x86/amd: support capturing LBR from software events |
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* Andrii Nakryiko <andrii@kernel.org> wrote:
> Now that it's possible to capture LBR on AMD CPU from BPF at arbitrary > point, there is no reason to artificially limit this feature to sampling > events. So corresponding check is removed. AFAIU, there is no > correctness implications of doing this (and it was possible to bypass > this check by just setting perf_event's sample_period to 1 anyways, so > it doesn't guard all that much).
> diff --git a/arch/x86/events/amd/lbr.c b/arch/x86/events/amd/lbr.c > index 4a1e600314d5..75920f895d67 100644 > --- a/arch/x86/events/amd/lbr.c > +++ b/arch/x86/events/amd/lbr.c > @@ -310,10 +310,6 @@ int amd_pmu_lbr_hw_config(struct perf_event *event) > { > int ret = 0; > > - /* LBR is not recommended in counting mode */ > - if (!is_sampling_event(event)) > - return -EINVAL; > -
Could you please split out this change into a separate patch?
Thanks,
Ingo
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