Re: [PATCH] drm/xe/debugfs: Move sa_info from gt to tile directory

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Fri, Aug 29, 2025 at 10:11:03PM +0200, Michal Wajdeczko wrote:
> Our drm-based suballocator is implemented per-tile so it is better
> to show its debug information also per-tile debugfs directory, not
> under per-gt directory as it is done today.
> 
> To allow adding more per-tile attributes, prepare necessary helper
> functions, like we already did for per-gt or per-uc attributes.
> 
> Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> Cc: Lucas De Marchi <lucas.demarchi@intel.com>

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

> ---
>  drivers/gpu/drm/xe/Makefile          |   1 +
>  drivers/gpu/drm/xe/xe_debugfs.c      |  20 +---
>  drivers/gpu/drm/xe/xe_gt_debugfs.c   |  13 ---
>  drivers/gpu/drm/xe/xe_tile_debugfs.c | 135 +++++++++++++++++++++++++++
>  drivers/gpu/drm/xe/xe_tile_debugfs.h |  13 +++
>  5 files changed, 151 insertions(+), 31 deletions(-)
>  create mode 100644 drivers/gpu/drm/xe/xe_tile_debugfs.c
>  create mode 100644 drivers/gpu/drm/xe/xe_tile_debugfs.h
> 
> diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile
> index 987e4fe10538..95c0f0a9b403 100644
> --- a/drivers/gpu/drm/xe/Makefile
> +++ b/drivers/gpu/drm/xe/Makefile
> @@ -325,6 +325,7 @@ ifeq ($(CONFIG_DEBUG_FS),y)
>  		xe_gt_stats.o \
>  		xe_guc_debugfs.o \
>  		xe_huc_debugfs.o \
> +		xe_tile_debugfs.o \
>  		xe_uc_debugfs.o
>  
>  	xe-$(CONFIG_PCI_IOV) += xe_gt_sriov_pf_debugfs.o
> diff --git a/drivers/gpu/drm/xe/xe_debugfs.c b/drivers/gpu/drm/xe/xe_debugfs.c
> index 8d6df6bd885e..4b71570529a6 100644
> --- a/drivers/gpu/drm/xe/xe_debugfs.c
> +++ b/drivers/gpu/drm/xe/xe_debugfs.c
> @@ -25,6 +25,7 @@
>  #include "xe_sriov.h"
>  #include "xe_sriov_pf.h"
>  #include "xe_step.h"
> +#include "xe_tile_debugfs.h"
>  #include "xe_wa.h"
>  #include "xe_vsec.h"
>  
> @@ -329,23 +330,6 @@ static const struct file_operations atomic_svm_timeslice_ms_fops = {
>  	.write = atomic_svm_timeslice_ms_set,
>  };
>  
> -static void create_tile_debugfs(struct xe_tile *tile, struct dentry *root)
> -{
> -	char name[8];
> -
> -	snprintf(name, sizeof(name), "tile%u", tile->id);
> -	tile->debugfs = debugfs_create_dir(name, root);
> -	if (IS_ERR(tile->debugfs))
> -		return;
> -
> -	/*
> -	 * Store the xe_tile pointer as private data of the tile/ directory
> -	 * node so other tile specific attributes under that directory may
> -	 * refer to it by looking at its parent node private data.
> -	 */
> -	tile->debugfs->d_inode->i_private = tile;
> -}
> -
>  void xe_debugfs_register(struct xe_device *xe)
>  {
>  	struct ttm_device *bdev = &xe->ttm;
> @@ -398,7 +382,7 @@ void xe_debugfs_register(struct xe_device *xe)
>  		ttm_resource_manager_create_debugfs(man, root, "stolen_mm");
>  
>  	for_each_tile(tile, xe, tile_id)
> -		create_tile_debugfs(tile, root);
> +		xe_tile_debugfs_register(tile);
>  
>  	for_each_gt(gt, xe, id)
>  		xe_gt_debugfs_register(gt);
> diff --git a/drivers/gpu/drm/xe/xe_gt_debugfs.c b/drivers/gpu/drm/xe/xe_gt_debugfs.c
> index bf3a67b5951c..f7a362ac8030 100644
> --- a/drivers/gpu/drm/xe/xe_gt_debugfs.c
> +++ b/drivers/gpu/drm/xe/xe_gt_debugfs.c
> @@ -123,18 +123,6 @@ static int powergate_info(struct xe_gt *gt, struct drm_printer *p)
>  	return ret;
>  }
>  
> -static int sa_info(struct xe_gt *gt, struct drm_printer *p)
> -{
> -	struct xe_tile *tile = gt_to_tile(gt);
> -
> -	xe_pm_runtime_get(gt_to_xe(gt));
> -	drm_suballoc_dump_debug_info(&tile->mem.kernel_bb_pool->base, p,
> -				     xe_sa_manager_gpu_addr(tile->mem.kernel_bb_pool));
> -	xe_pm_runtime_put(gt_to_xe(gt));
> -
> -	return 0;
> -}
> -
>  static int sa_info_vf_ccs(struct xe_gt *gt, struct drm_printer *p)
>  {
>  	struct xe_tile *tile = gt_to_tile(gt);
> @@ -316,7 +304,6 @@ static int hwconfig(struct xe_gt *gt, struct drm_printer *p)
>   * - without access to the PF specific data
>   */
>  static const struct drm_info_list vf_safe_debugfs_list[] = {
> -	{"sa_info", .show = xe_gt_debugfs_simple_show, .data = sa_info},
>  	{"topology", .show = xe_gt_debugfs_simple_show, .data = topology},
>  	{"ggtt", .show = xe_gt_debugfs_simple_show, .data = ggtt},
>  	{"register-save-restore", .show = xe_gt_debugfs_simple_show, .data = register_save_restore},
> diff --git a/drivers/gpu/drm/xe/xe_tile_debugfs.c b/drivers/gpu/drm/xe/xe_tile_debugfs.c
> new file mode 100644
> index 000000000000..5523874cba7b
> --- /dev/null
> +++ b/drivers/gpu/drm/xe/xe_tile_debugfs.c
> @@ -0,0 +1,135 @@
> +// SPDX-License-Identifier: MIT
> +/*
> + * Copyright © 2025 Intel Corporation
> + */
> +
> +#include <linux/debugfs.h>
> +#include <drm/drm_debugfs.h>
> +
> +#include "xe_pm.h"
> +#include "xe_sa.h"
> +#include "xe_tile_debugfs.h"
> +
> +static struct xe_tile *node_to_tile(struct drm_info_node *node)
> +{
> +	return node->dent->d_parent->d_inode->i_private;
> +}
> +
> +/**
> + * tile_debugfs_simple_show - A show callback for struct drm_info_list
> + * @m: the &seq_file
> + * @data: data used by the drm debugfs helpers
> + *
> + * This callback can be used in struct drm_info_list to describe debugfs
> + * files that are &xe_tile specific.
> + *
> + * It is assumed that those debugfs files will be created on directory entry
> + * which struct dentry d_inode->i_private points to &xe_tile.
> + *
> + *      /sys/kernel/debug/dri/0/
> + *      ├── tile0/		# tile = dentry->d_inode->i_private
> + *      │   │   ├── id		# tile = dentry->d_parent->d_inode->i_private
> + *
> + * This function assumes that &m->private will be set to the &struct
> + * drm_info_node corresponding to the instance of the info on a given &struct
> + * drm_minor (see struct drm_info_list.show for details).
> + *
> + * This function also assumes that struct drm_info_list.data will point to the
> + * function code that will actually print a file content::
> + *
> + *   int (*print)(struct xe_tile *, struct drm_printer *)
> + *
> + * Example::
> + *
> + *    int tile_id(struct xe_tile *tile, struct drm_printer *p)
> + *    {
> + *        drm_printf(p, "%u\n", tile->id);
> + *        return 0;
> + *    }
> + *
> + *    static const struct drm_info_list info[] = {
> + *        { name = "id", .show = tile_debugfs_simple_show, .data = tile_id },
> + *    };
> + *
> + *    dir = debugfs_create_dir("tile0", parent);
> + *    dir->d_inode->i_private = tile;
> + *    drm_debugfs_create_files(info, ARRAY_SIZE(info), dir, minor);
> + *
> + * Return: 0 on success or a negative error code on failure.
> + */
> +static int tile_debugfs_simple_show(struct seq_file *m, void *data)
> +{
> +	struct drm_printer p = drm_seq_file_printer(m);
> +	struct drm_info_node *node = m->private;
> +	struct xe_tile *tile = node_to_tile(node);
> +	int (*print)(struct xe_tile *, struct drm_printer *) = node->info_ent->data;
> +
> +	return print(tile, &p);
> +}
> +
> +/**
> + * tile_debugfs_show_with_rpm - A show callback for struct drm_info_list
> + * @m: the &seq_file
> + * @data: data used by the drm debugfs helpers
> + *
> + * Similar to tile_debugfs_simple_show() but implicitly takes a RPM ref.
> + *
> + * Return: 0 on success or a negative error code on failure.
> + */
> +static int tile_debugfs_show_with_rpm(struct seq_file *m, void *data)
> +{
> +	struct drm_info_node *node = m->private;
> +	struct xe_tile *tile = node_to_tile(node);
> +	struct xe_device *xe = tile_to_xe(tile);
> +	int ret;
> +
> +	xe_pm_runtime_get(xe);
> +	ret = tile_debugfs_simple_show(m, data);
> +	xe_pm_runtime_put(xe);
> +
> +	return ret;
> +}
> +
> +static int sa_info(struct xe_tile *tile, struct drm_printer *p)
> +{
> +	drm_suballoc_dump_debug_info(&tile->mem.kernel_bb_pool->base, p,
> +				     xe_sa_manager_gpu_addr(tile->mem.kernel_bb_pool));
> +
> +	return 0;
> +}
> +
> +/* only for debugfs files which can be safely used on the VF */
> +static const struct drm_info_list vf_safe_debugfs_list[] = {
> +	{ "sa_info", .show = tile_debugfs_show_with_rpm, .data = sa_info },
> +};
> +
> +/**
> + * xe_tile_debugfs_register - Register tile's debugfs attributes
> + * @tile: the &xe_tile to register
> + *
> + * Create debugfs sub-directory with a name that includes a tile ID and
> + * then creates set of debugfs files (attributes) specific to this tile.
> + */
> +void xe_tile_debugfs_register(struct xe_tile *tile)
> +{
> +	struct xe_device *xe = tile_to_xe(tile);
> +	struct drm_minor *minor = xe->drm.primary;
> +	struct dentry *root = minor->debugfs_root;
> +	char name[8];
> +
> +	snprintf(name, sizeof(name), "tile%u", tile->id);
> +	tile->debugfs = debugfs_create_dir(name, root);
> +	if (IS_ERR(tile->debugfs))
> +		return;
> +
> +	/*
> +	 * Store the xe_tile pointer as private data of the tile/ directory
> +	 * node so other tile specific attributes under that directory may
> +	 * refer to it by looking at its parent node private data.
> +	 */
> +	tile->debugfs->d_inode->i_private = tile;
> +
> +	drm_debugfs_create_files(vf_safe_debugfs_list,
> +				 ARRAY_SIZE(vf_safe_debugfs_list),
> +				 tile->debugfs, minor);
> +}
> diff --git a/drivers/gpu/drm/xe/xe_tile_debugfs.h b/drivers/gpu/drm/xe/xe_tile_debugfs.h
> new file mode 100644
> index 000000000000..0e5f724de37f
> --- /dev/null
> +++ b/drivers/gpu/drm/xe/xe_tile_debugfs.h
> @@ -0,0 +1,13 @@
> +/* SPDX-License-Identifier: MIT */
> +/*
> + * Copyright © 2025 Intel Corporation
> + */
> +
> +#ifndef _XE_TILE_DEBUGFS_H_
> +#define _XE_TILE_DEBUGFS_H_
> +
> +struct xe_tile;
> +
> +void xe_tile_debugfs_register(struct xe_tile *tile);
> +
> +#endif
> -- 
> 2.47.1
>