Re: [PATCH v12 09/10] perf/amd/iommu: Introduce amd_iommu-specific struct in struct hw_perf_event

From: Borislav Petkov
Date: Fri Mar 24 2017 - 13:54:51 EST


On Wed, Mar 22, 2017 at 02:02:41AM -0500, Suravee Suthikulpanit wrote:
> From: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
>
> Current AMD IOMMU Perf PMU inappropriately uses hardware struct
> inside the union inside the struct hw_perf_event, mainly the use of
> extra_reg.
>
> Instead, introduce amd_iommu-specific struct with required
> parameters to be programmed onto the IOMMU performance counter
> control register.
>
> Also update the pasid field from 16 to 20 bits.
>
> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> Cc: Borislav Petkov <bp@xxxxxxxxx>
> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
> ---
> arch/x86/events/amd/iommu.c | 102 +++++++++++++++++++-------------------------
> include/linux/perf_event.h | 7 +++
> 2 files changed, 52 insertions(+), 57 deletions(-)
>
> diff --git a/arch/x86/events/amd/iommu.c b/arch/x86/events/amd/iommu.c
> index 7ac8138..915a20c 100644
> --- a/arch/x86/events/amd/iommu.c
> +++ b/arch/x86/events/amd/iommu.c
> @@ -23,17 +23,16 @@
>
> #define COUNTER_SHIFT 16
>
> -#define _GET_BANK(ev) ((u8)(ev->hw.extra_reg.reg >> 8))
> -#define _GET_CNTR(ev) ((u8)(ev->hw.extra_reg.reg))
> -
> -/* iommu pmu config masks */
> -#define _GET_CSOURCE(ev) ((ev->hw.config & 0xFFULL))
> -#define _GET_DEVID(ev) ((ev->hw.config >> 8) & 0xFFFFULL)
> -#define _GET_PASID(ev) ((ev->hw.config >> 24) & 0xFFFFULL)
> -#define _GET_DOMID(ev) ((ev->hw.config >> 40) & 0xFFFFULL)
> -#define _GET_DEVID_MASK(ev) ((ev->hw.extra_reg.config) & 0xFFFFULL)
> -#define _GET_PASID_MASK(ev) ((ev->hw.extra_reg.config >> 16) & 0xFFFFULL)
> -#define _GET_DOMID_MASK(ev) ((ev->hw.extra_reg.config >> 32) & 0xFFFFULL)
> +/* iommu pmu conf masks */
> +#define GET_CSOURCE(x) (x->conf & 0xFFULL)

You need to prevent the macro arg from potentially wrong precedence
rules/multiple eval:

#define GET_CSOURCE(x) ((x)->conf & 0xFFULL)
^^^

I fixed them up when applying.

--
Regards/Gruss,
Boris.

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