On Thu, Sep 20, 2018 at 06:05:55PM +0800, Wei Wang wrote:
> diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c
> index c88ed39..c81f160 100644
> --- a/arch/x86/events/intel/lbr.c
> +++ b/arch/x86/events/intel/lbr.c
> @@ -1277,3 +1277,26 @@ void intel_pmu_lbr_init_knl(void)
> if (x86_pmu.intel_cap.lbr_format == LBR_FORMAT_LIP)
> x86_pmu.intel_cap.lbr_format = LBR_FORMAT_EIP_FLAGS;
> }
> +
> +/**
> + * perf_get_lbr_stack - get the lbr stack related MSRs
> + *
> + * @stack: the caller's memory to get the lbr stack
> + *
> + * Returns: 0 indicates that the lbr stack has been successfully obtained.
> + */
> +int perf_get_lbr_stack(struct perf_lbr_stack *stack)
> +{
> + stack->nr = x86_pmu.lbr_nr;
> + stack->tos = x86_pmu.lbr_tos;
> + stack->from = x86_pmu.lbr_from;
> + stack->to = x86_pmu.lbr_to;
> +
> + if (x86_pmu.intel_cap.lbr_format == LBR_FORMAT_INFO)
> + stack->info = MSR_LBR_INFO_0;
> + else
> + stack->info = 0;
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(perf_get_lbr_stack);
Blergh, I know KVM is a module but it really sucks having to export
everything :/
> diff --git a/arch/x86/include/asm/perf_event.h
> b/arch/x86/include/asm/perf_event.h
> index 12f5408..84cc8cb 100644
> --- a/arch/x86/include/asm/perf_event.h
> +++ b/arch/x86/include/asm/perf_event.h
> @@ -267,7 +267,16 @@ struct perf_guest_switch_msr {
> u64 host, guest;
> };
>
> +struct perf_lbr_stack {
> + int nr;
Do we need a negative number of LBR entries?
> + unsigned long tos;
> + unsigned long from;
> + unsigned long to;
> + unsigned long info;
These are all MSR values, that can be 'unsigned int', right? If so,
please also fix struct x86_pmu for that.
> +};
> +
> extern struct perf_guest_switch_msr *perf_guest_get_msrs(int *nr);
> +extern int perf_get_lbr_stack(struct perf_lbr_stack *stack);
> extern void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap);
> extern void perf_check_microcode(void);
> #else
I would like to use the x86_perf namespace or something along those
lines, this is very much not a generic perf interface -- it is very much
x86 (or rather even Intel) specific.
