[05/24] drm/omap: Use devm_kzalloc() to allocate omap_drm_private

Message ID 1518428694-18018-6-git-send-email-tomi.valkeinen@ti.com
State New
Headers show
Series
  • drm/omap: misc patches
Related show

Commit Message

Tomi Valkeinen Feb. 12, 2018, 9:44 a.m.
From: Peter Ujfalusi <peter.ujfalusi@ti.com>

It makes the cleanup paths a bit cleaner.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
---
 drivers/gpu/drm/omapdrm/omap_drv.c | 19 +++++++------------
 1 file changed, 7 insertions(+), 12 deletions(-)

Comments

Laurent Pinchart Feb. 27, 2018, 1:03 p.m. | #1
Hi Tomi,

Thank you for the patch.

On Monday, 12 February 2018 11:44:35 EET Tomi Valkeinen wrote:
> From: Peter Ujfalusi <peter.ujfalusi@ti.com>
> 
> It makes the cleanup paths a bit cleaner.

But it also goes in the wrong direction. The data structure is accessible 
after the .remove() handler returns and thus should outlive the probe/remove 
sequence through proper reference counting. We're of course not doing a good 
job here as we kfree() it in .remove() instead of reference-counting it 
properly, and that should be fixed, but this patch makes the fix more complex 
as we'll have to move back from devm_kzalloc().

> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
> ---
>  drivers/gpu/drm/omapdrm/omap_drv.c | 19 +++++++------------
>  1 file changed, 7 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/gpu/drm/omapdrm/omap_drv.c
> b/drivers/gpu/drm/omapdrm/omap_drv.c index 485684c637ff..3cd9188ab30b
> 100644
> --- a/drivers/gpu/drm/omapdrm/omap_drv.c
> +++ b/drivers/gpu/drm/omapdrm/omap_drv.c
> @@ -529,19 +529,17 @@ static int pdev_probe(struct platform_device *pdev)
>  		return ret;
>  	}
> 
> +	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
>  	omap_crtc_pre_init();
> 
>  	ret = omap_connect_dssdevs();
>  	if (ret)
>  		goto err_crtc_uninit;
> 
> -	/* Allocate and initialize the driver private structure. */
> -	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
> -	if (!priv) {
> -		ret = -ENOMEM;
> -		goto err_disconnect_dssdevs;
> -	}
> -
> +	/* Initialize the driver private structure. */
>  	priv->dispc_ops = dispc_get_ops();
> 
>  	soc = soc_device_match(omapdrm_soc_devices);
> @@ -555,7 +553,7 @@ static int pdev_probe(struct platform_device *pdev)
>  	ddev = drm_dev_alloc(&omap_drm_driver, &pdev->dev);
>  	if (IS_ERR(ddev)) {
>  		ret = PTR_ERR(ddev);
> -		goto err_free_priv;
> +		goto err_destroy_wq;
>  	}
> 
>  	ddev->dev_private = priv;
> @@ -610,10 +608,8 @@ static int pdev_probe(struct platform_device *pdev)
>  err_free_drm_dev:
>  	omap_gem_deinit(ddev);
>  	drm_dev_unref(ddev);
> -err_free_priv:
> +err_destroy_wq:
>  	destroy_workqueue(priv->wq);
> -	kfree(priv);
> -err_disconnect_dssdevs:
>  	omap_disconnect_dssdevs();
>  err_crtc_uninit:
>  	omap_crtc_pre_uninit();
> @@ -644,7 +640,6 @@ static int pdev_remove(struct platform_device *pdev)
>  	drm_dev_unref(ddev);
> 
>  	destroy_workqueue(priv->wq);
> -	kfree(priv);
> 
>  	omap_disconnect_dssdevs();
>  	omap_crtc_pre_uninit();

Patch

diff --git a/drivers/gpu/drm/omapdrm/omap_drv.c b/drivers/gpu/drm/omapdrm/omap_drv.c
index 485684c637ff..3cd9188ab30b 100644
--- a/drivers/gpu/drm/omapdrm/omap_drv.c
+++ b/drivers/gpu/drm/omapdrm/omap_drv.c
@@ -529,19 +529,17 @@  static int pdev_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
 	omap_crtc_pre_init();
 
 	ret = omap_connect_dssdevs();
 	if (ret)
 		goto err_crtc_uninit;
 
-	/* Allocate and initialize the driver private structure. */
-	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
-	if (!priv) {
-		ret = -ENOMEM;
-		goto err_disconnect_dssdevs;
-	}
-
+	/* Initialize the driver private structure. */
 	priv->dispc_ops = dispc_get_ops();
 
 	soc = soc_device_match(omapdrm_soc_devices);
@@ -555,7 +553,7 @@  static int pdev_probe(struct platform_device *pdev)
 	ddev = drm_dev_alloc(&omap_drm_driver, &pdev->dev);
 	if (IS_ERR(ddev)) {
 		ret = PTR_ERR(ddev);
-		goto err_free_priv;
+		goto err_destroy_wq;
 	}
 
 	ddev->dev_private = priv;
@@ -610,10 +608,8 @@  static int pdev_probe(struct platform_device *pdev)
 err_free_drm_dev:
 	omap_gem_deinit(ddev);
 	drm_dev_unref(ddev);
-err_free_priv:
+err_destroy_wq:
 	destroy_workqueue(priv->wq);
-	kfree(priv);
-err_disconnect_dssdevs:
 	omap_disconnect_dssdevs();
 err_crtc_uninit:
 	omap_crtc_pre_uninit();
@@ -644,7 +640,6 @@  static int pdev_remove(struct platform_device *pdev)
 	drm_dev_unref(ddev);
 
 	destroy_workqueue(priv->wq);
-	kfree(priv);
 
 	omap_disconnect_dssdevs();
 	omap_crtc_pre_uninit();