Re: [PATCH] drm/xe: Add a per-client debugfs file reporting bo NUMA node distribution

[Andi Shyti <andi.shyti@kernel.org>]

Hi Thomas,

On Wed, Oct 28, 2026 at 11:32:37AM +0100, Thomas Hellström wrote:
> When debugging NUMA placement of bo system memory, there is currently
> no way to tell on which nodes the pages backing a bo reside. The
> /proc/<pid>/numa_maps interface doesn't help since bo CPU mappings are
> VM_PFNMAP, and clients may have thousands of bos, so a dump of all bos
> is undesirable.

...

> Example:
>   exec 3<>/sys/kernel/debug/dri/client-<id>/bo_numa
>   echo <handle1> >&3
>   cat <&3
>   echo <handle2> >&3
>   cat <&3
>   exec 3>&-
> 
> The client id can be obtained from the drm-client-id fdinfo key.
> 
> Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> Cc: Matthew Brost <matthew.brost@intel.com>
> Cc: Matthew Auld <matthew.auld@intel.com>
> Assisted-by: LLM

Please drop the Assisted-by and add your SoB :-)

...

> +	do {
> +		kvfree(buf);
> +		bufsize *= 2;
> +		buf = kvzalloc(bufsize, GFP_KERNEL_ACCOUNT);
> +		if (!buf) {
> +			ret = -ENOMEM;
> +			goto out_unlock;
> +		}
> +
> +		iter = (struct drm_print_iterator) {
> +			.data = buf,
> +			.remain = bufsize,
> +		};
> +		p = drm_coredump_printer(&iter);
> +		ret = xe_bo_print_numa_info(file, handle, &p);
> +		if (ret)
> +			goto out_free;
> +	} while (!iter.remain);

this is basically

	} while(drm_coredump_printer_is_full(&p));

The rest looks good to me.

Andi