Re: [PATCH v14 7/7] drm/xe/pmu: Add GT C6 events

Riana Tauro
2025-01-22T10:23:53Z

On 1/22/2025 11:53 AM, Lucas De Marchi wrote:
> From: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
>
> Provide a PMU interface for GT C6 residency counters. The implementation
> is ported over from the i915 PMU code. Residency is provided in units of
> ms(like sysfs entry in - /sys/class/drm/card0/device/tile0/gt0/gtidle).
>
> Sample usage and output:
>
> $ perf list | grep gt-c6
> xe_0000_00_02.0/gt-c6-residency/ [Kernel PMU event]
>
> $ tail /sys/bus/event_source/devices/xe_0000_00_02.0/events/gt-c6-residency*
> ==> /sys/bus/event_source/devices/xe_0000_00_02.0/events/gt-c6-residency <==
> event=0x01
>
> ==> /sys/bus/event_source/devices/xe_0000_00_02.0/events/gt-c6-residency.unit <==
> ms
>
> $ perf stat -e xe_0000_00_02.0/gt-c6-residency,gt=0/ -I1000
> # time counts unit events
> 1.001196056 1,001 ms xe_0000_00_02.0/gt-c6-residency,gt=0/
> 2.005216219 1,003 ms xe_0000_00_02.0/gt-c6-residency,gt=0/
>
> Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
> Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Looks good to me
Reviewed-by: Riana Tauro <riana.tauro@intel.com>
> ---
> drivers/gpu/drm/xe/xe_pmu.c | 13 +++++++++++--
> 1 file changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/xe/xe_pmu.c b/drivers/gpu/drm/xe/xe_pmu.c
> index 8d938d67c1f2c..a2e4addd3dd7e 100644
> --- a/drivers/gpu/drm/xe/xe_pmu.c
> +++ b/drivers/gpu/drm/xe/xe_pmu.c
> @@ -11,6 +11,7 @@
> #include "xe_device.h"
> #include "xe_force_wake.h"
> #include "xe_gt_clock.h"
> +#include "xe_gt_idle.h"
> #include "xe_gt_printk.h"
> #include "xe_mmio.h"
> #include "xe_macros.h"
> @@ -122,12 +123,16 @@ static int xe_pmu_event_init(struct perf_event *event)
> static u64 __xe_pmu_event_read(struct perf_event *event)
> {
> struct xe_gt *gt = event_to_gt(event);
> - u64 val = 0;
>
> if (!gt)
> return 0;
>
> - return val;
> + switch (config_to_event_id(event->attr.config)) {
> + case XE_PMU_EVENT_GT_C6_RESIDENCY:
> + return xe_gt_idle_residency_msec(&gt->gtidle);
> + }
> +
> + return 0;
> }
>
> static void xe_pmu_event_update(struct perf_event *event)
> @@ -268,6 +273,10 @@ static const struct attribute_group pmu_events_attr_group = {
>
> static void set_supported_events(struct xe_pmu *pmu)
> {
> + struct xe_device *xe = container_of(pmu, typeof(*xe), pmu);
> +
> + if (!xe->info.skip_guc_pc)
> + pmu->supported_events |= BIT_ULL(XE_PMU_EVENT_GT_C6_RESIDENCY);
> }
>
> /**