Re: [PATCH 1/2] drm: Add DRM-managed alloc_workqueue() and alloc_ordered_workqueue()

[Daniel Vetter]

On Tue, Jan 10, 2023 at 11:24:47PM +0800, Jiasheng Jiang wrote:
> Add drmm_alloc_workqueue() and drmm_alloc_ordered_workqueue(), the helpers
> that provide managed workqueue cleanup. The workqueue will be destroyed
> with the final reference of the DRM device.
> 
> Signed-off-by: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>

Yeah I think this looks nice.

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

I'm assuming driver maintainers will pick this up, if not please holler.

Also the threading seems broken, it's not a patch series. The b4 tool or
git send-email (of all the patches of the entire series at once, not each
individually) should get this right.

Unfortunately I did't find the right link in the kernel docs, or at least
they're not as detailed as I hoped.

Also your previous submission had iirc a bunch more patches, do you plan
to include them all in the next patch set?
-Daniel


> ---
>  drivers/gpu/drm/drm_managed.c | 66 +++++++++++++++++++++++++++++++++++
>  include/drm/drm_managed.h     |  8 +++++
>  2 files changed, 74 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_managed.c b/drivers/gpu/drm/drm_managed.c
> index 4cf214de50c4..d3bd6247eec9 100644
> --- a/drivers/gpu/drm/drm_managed.c
> +++ b/drivers/gpu/drm/drm_managed.c
> @@ -271,6 +271,13 @@ static void drmm_mutex_release(struct drm_device *dev, void *res)
>  	mutex_destroy(lock);
>  }
>  
> +static void drmm_destroy_workqueue(struct drm_device *dev, void *res)
> +{
> +	struct workqueue_struct *wq = res;
> +
> +	destroy_workqueue(wq);
> +}
> +
>  /**
>   * drmm_mutex_init - &drm_device-managed mutex_init()
>   * @dev: DRM device
> @@ -289,3 +296,62 @@ int drmm_mutex_init(struct drm_device *dev, struct mutex *lock)
>  	return drmm_add_action_or_reset(dev, drmm_mutex_release, lock);
>  }
>  EXPORT_SYMBOL(drmm_mutex_init);
> +
> +/**
> + * drmm_alloc_workqueue - &drm_device-managed alloc_workqueue()
> + * @dev: DRM device
> + * @wq: workqueue to be allocated
> + *
> + * Returns:
> + * 0 on success, or a negative errno code otherwise.
> + *
> + * This is a &drm_device-managed version of alloc_workqueue().
> + * The initialized lock is automatically destroyed on the final
> + * drm_dev_put().
> + */
> +int drmm_alloc_workqueue(struct drm_device *dev,
> +			  struct workqueue_struct *wq, const char *fmt,
> +			  unsigned int flags, int max_active, ...)
> +{
> +	va_list args;
> +
> +	va_start(args, max_active);
> +	wq = alloc_workqueue(fmt, flags, max_active, args);
> +	va_end(args);
> +
> +	if (!wq)
> +		return -ENOMEM;
> +
> +	return drmm_add_action_or_reset(dev, drmm_destroy_workqueue, wq);
> +}
> +EXPORT_SYMBOL(drmm_alloc_workqueue);
> +
> +/**
> + * drmm_alloc_ordered_workqueue - &drm_device-managed
> + * alloc_ordered_workqueue()
> + * @dev: DRM device
> + * @wq: workqueue to be allocated
> + *
> + * Returns:
> + * 0 on success, or a negative errno code otherwise.
> + *
> + * This is a &drm_device-managed version of alloc_ordered_workqueue().
> + * The initialized lock is automatically destroyed on the final
> + * drm_dev_put().
> + */
> +int drmm_alloc_ordered_workqueue(struct drm_device *dev,
> +				  struct workqueue_struct *wq,
> +				  const char *fmt, unsigned int flags, ...)
> +{
> +	va_list args;
> +
> +	va_start(args, flags);
> +	wq = alloc_ordered_workqueue(fmt, flags, args);
> +	va_end(args);
> +
> +	if (!wq)
> +		return -ENOMEM;
> +
> +	return drmm_add_action_or_reset(dev, drmm_destroy_workqueue, wq);
> +}
> +EXPORT_SYMBOL(drmm_alloc_ordered_workqueue);
> diff --git a/include/drm/drm_managed.h b/include/drm/drm_managed.h
> index 359883942612..68cecc14e1af 100644
> --- a/include/drm/drm_managed.h
> +++ b/include/drm/drm_managed.h
> @@ -107,4 +107,12 @@ void drmm_kfree(struct drm_device *dev, void *data);
>  
>  int drmm_mutex_init(struct drm_device *dev, struct mutex *lock);
>  
> +int drmm_alloc_workqueue(struct drm_device *dev,
> +			  struct workqueue_struct *wq, const char *fmt,
> +			  unsigned int flags, int max_active, ...);
> +
> +int drmm_alloc_ordered_workqueue(struct drm_device *dev,
> +				  struct workqueue_struct *wq,
> +				  const char *fmt, unsigned int flags, ...);
> +
>  #endif
> -- 
> 2.25.1
> 

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