On Wed, Jan 11, 2023 at 01:50:06AM +0530, Deepak R Varma wrote:
> Using DEFINE_SIMPLE_ATTRIBUTE macro with the debugfs_create_file()
> function adds the overhead of introducing a proxy file operation
> functions to wrap the original read/write inside file removal protection
> functions. This adds significant overhead in terms of introducing and
> managing the proxy factory file operations structure and function
> wrapping at runtime.
> As a replacement, a combination of DEFINE_DEBUGFS_ATTRIBUTE macro paired
> with debugfs_create_file_unsafe() is suggested to be used instead. The
> DEFINE_DEBUGFS_ATTRIBUTE utilises debugfs_file_get() and
> debugfs_file_put() wrappers to protect the original read and write
> function calls for the debug attributes. There is no need for any
> runtime proxy file operations to be managed by the debugfs core.
> Following coccicheck make command helped identify this change:
>
> make coccicheck M=drivers/gpu/drm/i915/ MODE=patch COCCI=./scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci
>
> Signed-off-by: Deepak R Varma <drv@xxxxxxxxx>
> ---
> Note: Change cross compile tested using stm32_defconfig for arm
Hello,
Is there a feedback/comment on this patch proposal please? Let me know if I
should resend it.
Thank you,
./drv
>
> drivers/gpu/drm/sti/sti_drv.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/sti/sti_drv.c b/drivers/gpu/drm/sti/sti_drv.c
> index ef6a4e63198f..c9be82043638 100644
> --- a/drivers/gpu/drm/sti/sti_drv.c
> +++ b/drivers/gpu/drm/sti/sti_drv.c
> @@ -67,8 +67,8 @@ static int sti_drm_fps_set(void *data, u64 val)
> return 0;
> }
>
> -DEFINE_SIMPLE_ATTRIBUTE(sti_drm_fps_fops,
> - sti_drm_fps_get, sti_drm_fps_set, "%llu\n");
> +DEFINE_DEBUGFS_ATTRIBUTE(sti_drm_fps_fops,
> + sti_drm_fps_get, sti_drm_fps_set, "%llu\n");
>
> static int sti_drm_fps_dbg_show(struct seq_file *s, void *data)
> {
> @@ -97,8 +97,8 @@ static void sti_drm_dbg_init(struct drm_minor *minor)
> ARRAY_SIZE(sti_drm_dbg_list),
> minor->debugfs_root, minor);
>
> - debugfs_create_file("fps_show", S_IRUGO | S_IWUSR, minor->debugfs_root,
> - minor->dev, &sti_drm_fps_fops);
> + debugfs_create_file_unsafe("fps_show", S_IRUGO | S_IWUSR, minor->debugfs_root,
> + minor->dev, &sti_drm_fps_fops);
>
> DRM_INFO("%s: debugfs installed\n", DRIVER_NAME);
> }
> --
> 2.34.1
>
>
>
