Re: [PATCH] drm/xe/pmu/uapi: Remove PMU group busyness events from uapi

["Dixit, Ashutosh" <ashutosh.dixit@intel.com>]

On Fri, 08 Dec 2023 16:02:33 -0800, Ashutosh Dixit wrote:
>
> PMU group busyness uapi is likely to change in the future. Till the uapi is
> decided remove the uapi from xe_drm.h. To not break the build retain the
> events internally in xe_pmu.c for now.

This gets the job done of getting the PMU stuff out of the uapi, but not
sure if moving the defines in xe_pmu.c is ugly? The other easy option is to
just delete everything (maybe drop all PMU patches in a rebase). Later add
it back when some valid PMU stuff is added again.

Deleting the uapi but retaining the PMU infrastructure is a chore. I'd say
do something like this patch, or delete everything and start over.

>
> Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
> ---
>  drivers/gpu/drm/xe/xe_pmu.c | 39 +++++++++++++++++++++++++++++++++++++
>  include/uapi/drm/xe_drm.h   | 39 -------------------------------------
>  2 files changed, 39 insertions(+), 39 deletions(-)
>
> diff --git a/drivers/gpu/drm/xe/xe_pmu.c b/drivers/gpu/drm/xe/xe_pmu.c
> index 9d0b7887cfc45..d6fa7cdca9ede 100644
> --- a/drivers/gpu/drm/xe/xe_pmu.c
> +++ b/drivers/gpu/drm/xe/xe_pmu.c
> @@ -12,6 +12,45 @@
>  #include "xe_gt_clock.h"
>  #include "xe_mmio.h"
>
> +/**
> + * DOC: XE PMU event config IDs
> + *
> + * Check 'man perf_event_open' to use the ID's DRM_XE_PMU_XXXX listed in xe_drm.h
> + * in 'struct perf_event_attr' as part of perf_event_open syscall to read a
> + * particular event.
> + *
> + * For example to open the DRMXE_PMU_RENDER_GROUP_BUSY(0):
> + *
> + * .. code-block:: C
> + *
> + *	struct perf_event_attr attr;
> + *	long long count;
> + *	int cpu = 0;
> + *	int fd;
> + *
> + *	memset(&attr, 0, sizeof(struct perf_event_attr));
> + *	attr.type = type; // eg: /sys/bus/event_source/devices/xe_0000_56_00.0/type
> + *	attr.read_format = PERF_FORMAT_TOTAL_TIME_ENABLED;
> + *	attr.use_clockid = 1;
> + *	attr.clockid = CLOCK_MONOTONIC;
> + *	attr.config = DRM_XE_PMU_RENDER_GROUP_BUSY(0);
> + *
> + *	fd = syscall(__NR_perf_event_open, &attr, -1, cpu, -1, 0);
> + */
> +
> +/*
> + * Top bits of every counter are GT id.
> + */
> +#define __DRM_XE_PMU_GT_SHIFT (56)
> +
> +#define ___DRM_XE_PMU_OTHER(gt, x) \
> +	(((__u64)(x)) | ((__u64)(gt) << __DRM_XE_PMU_GT_SHIFT))
> +
> +#define DRM_XE_PMU_RENDER_GROUP_BUSY(gt)	___DRM_XE_PMU_OTHER(gt, 0)
> +#define DRM_XE_PMU_COPY_GROUP_BUSY(gt)		___DRM_XE_PMU_OTHER(gt, 1)
> +#define DRM_XE_PMU_MEDIA_GROUP_BUSY(gt)		___DRM_XE_PMU_OTHER(gt, 2)
> +#define DRM_XE_PMU_ANY_ENGINE_GROUP_BUSY(gt)	___DRM_XE_PMU_OTHER(gt, 3)
> +
>  static cpumask_t xe_pmu_cpumask;
>  static unsigned int xe_pmu_target_cpu = -1;
>
> diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
> index 0895e4d2a9815..64498c762d8b9 100644
> --- a/include/uapi/drm/xe_drm.h
> +++ b/include/uapi/drm/xe_drm.h
> @@ -1081,45 +1081,6 @@ struct drm_xe_wait_user_fence {
>	__u64 reserved[2];
>  };
>
> -/**
> - * DOC: XE PMU event config IDs
> - *
> - * Check 'man perf_event_open' to use the ID's DRM_XE_PMU_XXXX listed in xe_drm.h
> - * in 'struct perf_event_attr' as part of perf_event_open syscall to read a
> - * particular event.
> - *
> - * For example to open the DRMXE_PMU_RENDER_GROUP_BUSY(0):
> - *
> - * .. code-block:: C
> - *
> - *	struct perf_event_attr attr;
> - *	long long count;
> - *	int cpu = 0;
> - *	int fd;
> - *
> - *	memset(&attr, 0, sizeof(struct perf_event_attr));
> - *	attr.type = type; // eg: /sys/bus/event_source/devices/xe_0000_56_00.0/type
> - *	attr.read_format = PERF_FORMAT_TOTAL_TIME_ENABLED;
> - *	attr.use_clockid = 1;
> - *	attr.clockid = CLOCK_MONOTONIC;
> - *	attr.config = DRM_XE_PMU_RENDER_GROUP_BUSY(0);
> - *
> - *	fd = syscall(__NR_perf_event_open, &attr, -1, cpu, -1, 0);
> - */
> -
> -/*
> - * Top bits of every counter are GT id.
> - */
> -#define __DRM_XE_PMU_GT_SHIFT (56)
> -
> -#define ___DRM_XE_PMU_OTHER(gt, x) \
> -	(((__u64)(x)) | ((__u64)(gt) << __DRM_XE_PMU_GT_SHIFT))
> -
> -#define DRM_XE_PMU_RENDER_GROUP_BUSY(gt)	___DRM_XE_PMU_OTHER(gt, 0)
> -#define DRM_XE_PMU_COPY_GROUP_BUSY(gt)		___DRM_XE_PMU_OTHER(gt, 1)
> -#define DRM_XE_PMU_MEDIA_GROUP_BUSY(gt)		___DRM_XE_PMU_OTHER(gt, 2)
> -#define DRM_XE_PMU_ANY_ENGINE_GROUP_BUSY(gt)	___DRM_XE_PMU_OTHER(gt, 3)
> -
>  #if defined(__cplusplus)
>  }
>  #endif
> --
> 2.41.0
>