Re: [PATCH v7 0/7] Add support for EU stall sampling

[Harish Chegondi <harish.chegondi@intel.com>]

On Fri, Dec 20, 2024 at 03:22:49AM -0800, Harish Chegondi wrote:
> The following patch series add support for EU stall sampling,
> a new hardware feature first added in PVC and is being supported
> in XE2 and later architecture GPUs. This feature would enable
> capturing of EU stall data which include the IP address of the
> instruction stalled and various stall reason counts.
> 
> Support for this feature is being added into Mesa.
> https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/30142
> 
> A new test in the IGT repo:
> https://gitlab.freedesktop.org/drm/igt-gpu-tools.git
> is also under development to test this feature in the driver. This
> patch has undergone basic testing with the new IGT test that is under
> development.
IGT patch that adds tests for EU stall sampling is:
https://patchwork.freedesktop.org/series/143030/

> Thank You.
-Harish.
> 
> v7: a. Renamed input property DRM_XE_EU_STALL_PROP_EVENT_REPORT_COUNT
>        to DRM_XE_EU_STALL_PROP_WAIT_NUM_REPORTS to be consistent with
>        OA. Renamed the corresponding internal variables.
>     b. Fixed some commit messages based on review feedback.
>     c. Changed sampling_rates from a pointer to flexible array.
> 
> v6: a. Changed the uAPI input to accept sampling rate in GPU cycles
>        instead of sampling rate multiplier.
>     b. Fix buffer wrap around over write bug (Matt Olson).
>     c. Include EU stall sampling rates information and per XeCore buffer size in the query information.
> 
> v5: Addressed review feedback from v4 including
>     a. Removed DRM_XE_EU_STALL_PROP_POLL_PERIOD from the uAPI (Ashutosh)
>     b. Separated the patches for Xe_HPC and Xe2 (Matt R)
>     c. Moved read() returning -EIO into a separate patch
>     d. Removed spinlocks around set_bit() and clear_bit() (Matt R)
>     e. Renamed several variables, structures and enums (Ashutosh and
> Matt R)
>     f. Addressed other review feedback.
> v4: Addressed review feedback from v3 including
>     a. Split the patch into multiple patches (Matt R)
>     b. Added a new device query to get EU stall info (Ashutosh)
>     c. Renamed all Dss to xecore (Matt R)
>     d. Removed buffer size and disable at open input properties. (Matt R)
>     e. Removed the "_SHIFT" macros (Matt R)
>     f. Allocate the EU stall buffer only on system memory.
>     g. Changed the work arounds to OOB (Matt R)
>     h. Other review feedback.
> v3: a. Removed data header and changed read() to return -EIO when data is dropped by the HW.
>     b. Added a new DRM_XE_OBSERVATION_IOCTL_INFO to query EU stall data record info
>     c. Added struct drm_xe_eu_stall_data_pvc and struct drm_xe_eu_stall_data_xe2
>        to xe_drm.h. These declarations would help user space to parse the
>        EU stall data
>     d. Addressed other review comments from v2
> v2: Rename xe perf layer as xe observation layer (Ashutosh)
> 
> Cc: Felix Degrood <felix.j.degrood@intel.com>
> Signed-off-by: Harish Chegondi <harish.chegondi@intel.com>
> Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
> 
> Harish Chegondi (7):
>   drm/xe/topology: Add a function to find the index of the last enabled
>     DSS in a mask
>   drm/xe/uapi: Introduce API for EU stall sampling
>   drm/xe/eustall: Implement EU stall sampling APIs for Xe_HPC
>   drm/xe/eustall: Return -EIO error from read() if HW drops data
>   drm/xe/eustall: Add EU stall sampling support for Xe2
>   drm/xe/uapi: Add a device query to get EU stall sampling information
>   drm/xe/eustall: Add workaround 22016596838 which applies to PVC.
> 
>  drivers/gpu/drm/xe/Makefile                |    1 +
>  drivers/gpu/drm/xe/regs/xe_eu_stall_regs.h |   29 +
>  drivers/gpu/drm/xe/xe_eu_stall.c           | 1103 ++++++++++++++++++++
>  drivers/gpu/drm/xe/xe_eu_stall.h           |   61 ++
>  drivers/gpu/drm/xe/xe_gt.c                 |    6 +
>  drivers/gpu/drm/xe/xe_gt_topology.h        |   13 +
>  drivers/gpu/drm/xe/xe_gt_types.h           |    3 +
>  drivers/gpu/drm/xe/xe_observation.c        |   14 +
>  drivers/gpu/drm/xe/xe_query.c              |   38 +
>  drivers/gpu/drm/xe/xe_trace.h              |   33 +
>  drivers/gpu/drm/xe/xe_wa_oob.rules         |    1 +
>  include/uapi/drm/xe_drm.h                  |   74 ++
>  12 files changed, 1376 insertions(+)
>  create mode 100644 drivers/gpu/drm/xe/regs/xe_eu_stall_regs.h
>  create mode 100644 drivers/gpu/drm/xe/xe_eu_stall.c
>  create mode 100644 drivers/gpu/drm/xe/xe_eu_stall.h
> 
> -- 
> 2.47.1
>