Re: [PATCH v2 3/4] drm/msm/debugfs: Use cleanup.h for gpu state dump

[Konrad Dybcio]

On 11/2/26 8:00 PM, Rob Clark wrote:
> We need to move the gpu lock around a bit for the next patch.  Use
> scoped_guard/etc so we don't have to make the error path handling more
> complicated.
> 
> Signed-off-by: Rob Clark <robin.clark@xxxxxxxxxxxxxxxx>
> ---
>  drivers/gpu/drm/msm/msm_debugfs.c | 31 ++++++++++++-------------------
>  1 file changed, 12 insertions(+), 19 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/msm_debugfs.c b/drivers/gpu/drm/msm/msm_debugfs.c
> index f12701e286ec..aa59b28a3392 100644
> --- a/drivers/gpu/drm/msm/msm_debugfs.c
> +++ b/drivers/gpu/drm/msm/msm_debugfs.c
> @@ -70,43 +70,36 @@ static int msm_gpu_open(struct inode *inode, struct file *file)
>  	struct drm_device *dev = inode->i_private;
>  	struct msm_drm_private *priv = dev->dev_private;
>  	struct msm_gpu *gpu = priv->gpu;
> -	struct msm_gpu_show_priv *show_priv;
>  	int ret;
>  
>  	if (!gpu || !gpu->funcs->gpu_state_get)
>  		return -ENODEV;
>  
> -	show_priv = kmalloc_obj(*show_priv);
> +	struct msm_gpu_show_priv *show_priv __free(kfree)
> +		= kmalloc_obj(*show_priv);
>  	if (!show_priv)
>  		return -ENOMEM;
>  
> -	ret = mutex_lock_interruptible(&gpu->lock);
> -	if (ret)
> -		goto free_priv;
> -
> -	pm_runtime_get_sync(&gpu->pdev->dev);
> -	msm_gpu_hw_init(gpu);
> -	show_priv->state = gpu->funcs->gpu_state_get(gpu);
> -	pm_runtime_put_sync(&gpu->pdev->dev);
> -
> -	mutex_unlock(&gpu->lock);
> +	scoped_guard (pm_runtime_active, &gpu->pdev->dev) {
> +		scoped_cond_guard (mutex_intr, return -EINTR, &gpu->lock) {
> +			msm_gpu_hw_init(gpu);
> +			show_priv->state = gpu->funcs->gpu_state_get(gpu);
> +		}

My clanker tells me we can't grab the PM reference before a mutex,
as the recovery mechanism depends on the rpm count being appropriate
to let it drop it (and kill gx this way)

Konrad