On 09/07/2018 11:28 AM, Andi Kleen wrote:
+int perf_get_lbr_stack(struct perf_lbr_stack *stack) +{ + stack->lbr_nr = x86_pmu.lbr_nr; + stack->lbr_tos = x86_pmu.lbr_tos; + stack->lbr_from = x86_pmu.lbr_from; + stack->lbr_to = x86_pmu.lbr_to; + + if (x86_pmu.intel_cap.lbr_format == LBR_FORMAT_INFO) + stack->lbr_info = MSR_LBR_INFO_0; + else + stack->lbr_info = 0;Seems weird to export the enum value if the enum isn't exported. How can it be used?
I'm not sure about the issue. The caller gets the value of MSR_LBR_INFO_0 (not the enum, LBR_FORMAT_INFO) only when the hardware supports it. If hardware doesn't support it, just sets it to 0, and there will be no lbr info msr to be passed through.
Best, Wei
