Linux Virtualization - Mar 2020 - [PATCH 09/51] drm/cirrus: Use drmm_add_final_kfree

With this we can drop the final kfree from the release function.

I also noticed that cirrus forgot to call drm_dev_fini().

v2: Don't call kfree(cirrus) after we've handed overship of that to
drm_device and the drmm_ stuff.

Acked-by: Sam Ravnborg <sam at ravnborg.org>
Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
Cc: Dave Airlie <airlied at redhat.com>
Cc: Gerd Hoffmann <kraxel at redhat.com>
Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
Cc: "Noralf Tr?nnes" <noralf at tronnes.org>
Cc: Linus Walleij <linus.walleij at linaro.org>
Cc: Sam Ravnborg <sam at ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann at suse.de>
Cc: virtualization at lists.linux-foundation.org
---
 drivers/gpu/drm/cirrus/cirrus.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/cirrus/cirrus.c b/drivers/gpu/drm/cirrus/cirrus.c
index d2ff63ce8eaf..2232556ce34c 100644
--- a/drivers/gpu/drm/cirrus/cirrus.c
+++ b/drivers/gpu/drm/cirrus/cirrus.c
@@ -35,6 +35,7 @@
 #include <drm/drm_gem_shmem_helper.h>
 #include <drm/drm_gem_framebuffer_helper.h>
 #include <drm/drm_ioctl.h>
+#include <drm/drm_managed.h>
 #include <drm/drm_modeset_helper_vtables.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_simple_kms_helper.h>
@@ -527,10 +528,8 @@ static void cirrus_mode_config_init(struct cirrus_device
*cirrus)
 
 static void cirrus_release(struct drm_device *dev)
 {
-	struct cirrus_device *cirrus = dev->dev_private;
-
 	drm_mode_config_cleanup(dev);
-	kfree(cirrus);
+	drm_dev_fini(dev);
 }
 
 DEFINE_DRM_GEM_FOPS(cirrus_fops);
@@ -575,9 +574,12 @@ static int cirrus_pci_probe(struct pci_dev *pdev,
 
 	dev = &cirrus->dev;
 	ret = drm_dev_init(dev, &cirrus_driver, &pdev->dev);
-	if (ret)
-		goto err_free_cirrus;
+	if (ret) {
+		kfree(cirrus);
+		goto err_pci_release;
+	}
 	dev->dev_private = cirrus;
+	drmm_add_final_kfree(dev, cirrus);
 
 	ret = -ENOMEM;
 	cirrus->vram = ioremap(pci_resource_start(pdev, 0),
@@ -618,8 +620,6 @@ static int cirrus_pci_probe(struct pci_dev *pdev,
 	iounmap(cirrus->vram);
 err_dev_put:
 	drm_dev_put(dev);
-err_free_cirrus:
-	kfree(cirrus);
 err_pci_release:
 	pci_release_regions(pdev);
 	return ret;
-- 
2.24.1

> @@ -575,9 +574,12 @@ static int cirrus_pci_probe(struct pci_dev *pdev,
>  
>  	dev = &cirrus->dev;
>  	ret = drm_dev_init(dev, &cirrus_driver, &pdev->dev);
> -	if (ret)
> -		goto err_free_cirrus;
> +	if (ret) {
> +		kfree(cirrus);
> +		goto err_pci_release;
> +	}
>  	dev->dev_private = cirrus;
> +	drmm_add_final_kfree(dev, cirrus);
That doesn't look like an error path improvement.
With patch #30 applied it'll looks alot better though.
So maybe squash the patches?

In any case:
Acked-by: Gerd Hoffmann <kraxel at redhat.com>

cheers,
  Gerd

On Tue, Mar 03, 2020 at 08:49:34AM +0100, Gerd Hoffmann
wrote:
> > @@ -575,9 +574,12 @@ static int cirrus_pci_probe(struct pci_dev *pdev,
> >  
> >  	dev = &cirrus->dev;
> >  	ret = drm_dev_init(dev, &cirrus_driver, &pdev->dev);
> > -	if (ret)
> > -		goto err_free_cirrus;
> > +	if (ret) {
> > +		kfree(cirrus);
> > +		goto err_pci_release;
> > +	}
> >  	dev->dev_private = cirrus;
> > +	drmm_add_final_kfree(dev, cirrus);
> 
> That doesn't look like an error path improvement.
> With patch #30 applied it'll looks alot better though.
> So maybe squash the patches?
Breaks the patch set evolution, there's a _lot_ of dependencies in here to
make sure we never break anything interim. But yeah that's why I created
this entire series, since with just the first part it's really not any
better. I also have a pile more ideas on top, so hopefully once this lands
I can get around to them and make everything even better :-)

Cheers, Daniel
> 
> In any case:
> Acked-by: Gerd Hoffmann <kraxel at redhat.com>
> 
> cheers,
>   Gerd
> 
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch