Re: [PATCH v2] drm: add logging for RMFB ioctl

[Daniel Vetter <daniel@ffwll.ch>]

On Mon, Jul 26, 2021 at 07:49:06AM +0000, Simon Ser wrote:
> We already have logging for ADDFB2. Add some logging for RMFB as
> well.
> 
> This can be handy when trying to find out why a CRTC gets magically
> disabled.
> 
> v2: make log message more explicit, add log messages to
> drm_framebuffer_remove (Daniel)
> 
> Signed-off-by: Simon Ser <contact@emersion.fr>
> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

> ---
>  drivers/gpu/drm/drm_framebuffer.c | 22 +++++++++++++++++++++-
>  1 file changed, 21 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/drm_framebuffer.c b/drivers/gpu/drm/drm_framebuffer.c
> index 4d01464b6f95..d3d09aba9833 100644
> --- a/drivers/gpu/drm/drm_framebuffer.c
> +++ b/drivers/gpu/drm/drm_framebuffer.c
> @@ -404,6 +404,9 @@ static void drm_mode_rmfb_work_fn(struct work_struct *w)
>  		struct drm_framebuffer *fb =
>  			list_first_entry(&arg->fbs, typeof(*fb), filp_head);
>  
> +		drm_dbg_kms(fb->dev,
> +			    "Removing [FB:%d] from all active usage due to RMFB ioctl\n",
> +			    fb->base.id);
>  		list_del_init(&fb->filp_head);
>  		drm_framebuffer_remove(fb);
>  	}
> @@ -981,6 +984,10 @@ static int atomic_remove_fb(struct drm_framebuffer *fb)
>  		if (plane->state->fb != fb)
>  			continue;
>  
> +		drm_dbg_kms(dev,
> +			    "Disabling [PLANE:%d:%s] because [FB:%d] is removed\n",
> +			    plane->base.id, plane->name, fb->base.id);
> +
>  		plane_state = drm_atomic_get_plane_state(state, plane);
>  		if (IS_ERR(plane_state)) {
>  			ret = PTR_ERR(plane_state);
> @@ -990,6 +997,11 @@ static int atomic_remove_fb(struct drm_framebuffer *fb)
>  		if (disable_crtcs && plane_state->crtc->primary == plane) {
>  			struct drm_crtc_state *crtc_state;
>  
> +			drm_dbg_kms(dev,
> +				    "Disabling [CRTC:%d:%s] because [FB:%d] is removed\n",
> +				    plane_state->crtc->base.id,
> +				    plane_state->crtc->name, fb->base.id);
> +
>  			crtc_state = drm_atomic_get_existing_crtc_state(state, plane_state->crtc);
>  
>  			ret = drm_atomic_add_affected_connectors(state, plane_state->crtc);
> @@ -1052,6 +1064,10 @@ static void legacy_remove_fb(struct drm_framebuffer *fb)
>  	/* remove from any CRTC */
>  	drm_for_each_crtc(crtc, dev) {
>  		if (crtc->primary->fb == fb) {
> +			drm_dbg_kms(dev,
> +				    "Disabling [CRTC:%d:%s] because [FB:%d] is removed\n",
> +				    crtc->base.id, crtc->name, fb->base.id);
> +
>  			/* should turn off the crtc */
>  			if (drm_crtc_force_disable(crtc))
>  				DRM_ERROR("failed to reset crtc %p when fb was deleted\n", crtc);
> @@ -1059,8 +1075,12 @@ static void legacy_remove_fb(struct drm_framebuffer *fb)
>  	}
>  
>  	drm_for_each_plane(plane, dev) {
> -		if (plane->fb == fb)
> +		if (plane->fb == fb) {
> +			drm_dbg_kms(dev,
> +				    "Disabling [PLANE:%d:%s] because [FB:%d] is removed\n",
> +				    plane->base.id, plane->name, fb->base.id);
>  			drm_plane_force_disable(plane);
> +		}
>  	}
>  	drm_modeset_unlock_all(dev);
>  }
> -- 
> 2.32.0
> 
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch