On 6/18/25 15:47, Sunil Khatri wrote:
> add support to add a directory for each client-id
> with root at the dri level. Since the clients are
> unique and not just related to one single drm device,
> so it makes more sense to add all the client based
> nodes with root as dri.
>
> Also create a symlink back to the parent drm device
> from each client.
>
> Signed-off-by: Sunil Khatri <sunil.kha...@amd.com>
> ---
> drivers/gpu/drm/drm_debugfs.c | 32 ++++++++++++++++++++++++++++++++
> drivers/gpu/drm/drm_file.c | 10 ++++++++++
> include/drm/drm_debugfs.h | 12 ++++++++++++
> include/drm/drm_file.h | 7 +++++++
> 4 files changed, 61 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c
> index 5a33ec299c04..875276d5fb9f 100644
> --- a/drivers/gpu/drm/drm_debugfs.c
> +++ b/drivers/gpu/drm/drm_debugfs.c
> @@ -298,6 +298,38 @@ void drm_debugfs_remove_dir(void)
> debugfs_remove(drm_debugfs_root);
> }
>
> +int drm_debugfs_clients_add(struct drm_file *file)
> +{
> + struct drm_device *dev;
> + char *client_dir, *symlink;
> +
> + dev = file->minor->dev;
> +
> + client_dir = kasprintf(GFP_KERNEL, "client-%llu", file->client_id);
> + if (!client_dir)
> + return -ENOMEM;
> +
> + /* Create a debugfs directory for the client in root on drm debugfs */
That comments on what is done, so probably not a good idea.
But we should certainly have some explanation why we do this! Probably best to
add some overview under Documentation/gpu.
Apart from that this works technically for me.
Regards,
Christian.
> + file->debugfs_client = debugfs_create_dir(client_dir, drm_debugfs_root);
> + kfree(client_dir);
> +
> + symlink = kasprintf(GFP_KERNEL, "../%s", dev->unique);
> + if (!symlink)
> + return -ENOMEM;
> +
> + /* Create a link from client_id to the drm device this client id
> belongs to */
> + debugfs_create_symlink("device", file->debugfs_client, symlink);
> + kfree(symlink);
> +
> + return 0;
> +}
> +
> +void drm_debugfs_clients_remove(struct drm_file *file)
> +{
> + debugfs_remove_recursive(file->debugfs_client);
> + file->debugfs_client = NULL;
> +}
> +
> /**
> * drm_debugfs_dev_init - create debugfs directory for the device
> * @dev: the device which we want to create the directory for
> diff --git a/drivers/gpu/drm/drm_file.c b/drivers/gpu/drm/drm_file.c
> index 06ba6dcbf5ae..8502c5a630b1 100644
> --- a/drivers/gpu/drm/drm_file.c
> +++ b/drivers/gpu/drm/drm_file.c
> @@ -39,12 +39,14 @@
> #include <linux/poll.h>
> #include <linux/slab.h>
> #include <linux/vga_switcheroo.h>
> +#include <linux/debugfs.h>
>
> #include <drm/drm_client_event.h>
> #include <drm/drm_drv.h>
> #include <drm/drm_file.h>
> #include <drm/drm_gem.h>
> #include <drm/drm_print.h>
> +#include <drm/drm_debugfs.h>
>
> #include "drm_crtc_internal.h"
> #include "drm_internal.h"
> @@ -143,6 +145,13 @@ struct drm_file *drm_file_alloc(struct drm_minor *minor)
> rcu_assign_pointer(file->pid, get_pid(task_tgid(current)));
> file->minor = minor;
>
> + ret = drm_debugfs_clients_add(file);
> + if (ret) {
> + put_pid(rcu_access_pointer(file->pid));
> + kfree(file);
> + return ERR_PTR(ret);
> + }
> +
> /* for compatibility root is always authenticated */
> file->authenticated = capable(CAP_SYS_ADMIN);
>
> @@ -236,6 +245,7 @@ void drm_file_free(struct drm_file *file)
> atomic_read(&dev->open_count));
>
> drm_events_release(file);
> + drm_debugfs_clients_remove(file);
>
> if (drm_core_check_feature(dev, DRIVER_MODESET)) {
> drm_fb_release(file);
> diff --git a/include/drm/drm_debugfs.h b/include/drm/drm_debugfs.h
> index cf06cee4343f..4bd6cc1d0900 100644
> --- a/include/drm/drm_debugfs.h
> +++ b/include/drm/drm_debugfs.h
> @@ -153,6 +153,9 @@ void drm_debugfs_add_files(struct drm_device *dev,
>
> int drm_debugfs_gpuva_info(struct seq_file *m,
> struct drm_gpuvm *gpuvm);
> +
> +int drm_debugfs_clients_add(struct drm_file *file);
> +void drm_debugfs_clients_remove(struct drm_file *file);
> #else
> static inline void drm_debugfs_create_files(const struct drm_info_list
> *files,
> int count, struct dentry *root,
> @@ -181,6 +184,15 @@ static inline int drm_debugfs_gpuva_info(struct seq_file
> *m,
> {
> return 0;
> }
> +
> +int drm_debugfs_clients_add(struct drm_file *file)
> +{
> + return 0;
> +}
> +
> +void drm_debugfs_clients_remove(struct drm_file *file)
> +{
> +}
> #endif
>
> #endif /* _DRM_DEBUGFS_H_ */
> diff --git a/include/drm/drm_file.h b/include/drm/drm_file.h
> index 5c3b2aa3e69d..eab7546aad79 100644
> --- a/include/drm/drm_file.h
> +++ b/include/drm/drm_file.h
> @@ -400,6 +400,13 @@ struct drm_file {
> * @client_name_lock: Protects @client_name.
> */
> struct mutex client_name_lock;
> +
> + /**
> + * @debugfs_client:
> + *
> + * debugfs directory for each client under a drm node.
> + */
> + struct dentry *debugfs_client;
> };
>
> /**
