Re: [PATCH 1/2] drm/v3d: switch to drmm_mutex_init

From: Daniel Vetter
Date: Tue Nov 08 2022 - 10:57:03 EST


On Mon, Nov 07, 2022 at 07:46:55PM -0300, Maíra Canal wrote:
> mutex_init() is supposed to be balanced by a call to mutex_destroy(), but
> this is not currently happening on the v3d driver.
>
> Considering the introduction of a DRM-managed mutex_init variant, switch
> to drmm_mutex_init.
>
> Signed-off-by: Maíra Canal <mcanal@xxxxxxxxxx>

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

> ---
> drivers/gpu/drm/v3d/v3d_gem.c | 17 +++++++++++++----
> 1 file changed, 13 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c
> index b8980440d137..96af1cb5202a 100644
> --- a/drivers/gpu/drm/v3d/v3d_gem.c
> +++ b/drivers/gpu/drm/v3d/v3d_gem.c
> @@ -10,6 +10,7 @@
> #include <linux/sched/signal.h>
> #include <linux/uaccess.h>
>
> +#include <drm/drm_managed.h>
> #include <drm/drm_syncobj.h>
> #include <uapi/drm/v3d_drm.h>
>
> @@ -1075,10 +1076,18 @@ v3d_gem_init(struct drm_device *dev)
>
> spin_lock_init(&v3d->mm_lock);
> spin_lock_init(&v3d->job_lock);
> - mutex_init(&v3d->bo_lock);
> - mutex_init(&v3d->reset_lock);
> - mutex_init(&v3d->sched_lock);
> - mutex_init(&v3d->cache_clean_lock);
> + ret = drmm_mutex_init(dev, &v3d->bo_lock);
> + if (ret)
> + return ret;
> + ret = drmm_mutex_init(dev, &v3d->reset_lock);
> + if (ret)
> + return ret;
> + ret = drmm_mutex_init(dev, &v3d->sched_lock);
> + if (ret)
> + return ret;
> + ret = drmm_mutex_init(dev, &v3d->cache_clean_lock);
> + if (ret)
> + return ret;
>
> /* Note: We don't allocate address 0. Various bits of HW
> * treat 0 as special, such as the occlusion query counters
> --
> 2.38.1
>

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