Re: [PATCH] drm/v3d: Use kvcalloc

[Harshit Mogalapalli]

Hi Joe,

On 13/03/22 3:57 am, Joe Perches wrote:
> On Sat, 2022-03-12 at 07:26 -0800, Harshit Mogalapalli wrote:
> > kvcalloc is same as kvmalloc_array + __GFP_ZERO.
> []
> > diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c
> []
> > @@ -308,9 +308,8 @@ v3d_lookup_bos(struct drm_device *dev,
> >   		return -EINVAL;
> >   	}
> >   
> > -	job->bo = kvmalloc_array(job->bo_count,
> > -				 sizeof(struct drm_gem_cma_object *),
> > -				 GFP_KERNEL | __GFP_ZERO);
> > +	job->bo = kvcalloc(job->bo_count, sizeof(struct drm_gem_cma_object *),
> > +			   GFP_KERNEL);
> >   	if (!job->bo) {
> >   		DRM_DEBUG("Failed to allocate validated BO pointers\n");
> >   		return -ENOMEM;
>
> trivia:
>
> The DRM_DEBUG could also be removed as the the alloc will do a
> a dump_stack on failure.
Thanks for sharing your comments.

DRM_DEBUG statements are present in other parts of code as well. So 
didnot remove it.

Example below:
drivers/gpu/drm/v3d/v3d_gem.c at 322.

 311         job->bo = kvmalloc_array(job->bo_count,
 312                                  sizeof(struct drm_gem_cma_object *),
 313                                  GFP_KERNEL | __GFP_ZERO);
 314         if (!job->bo) {
 315                 DRM_DEBUG("Failed to allocate validated BO 
pointers\n");
 316                 return -ENOMEM;
 317         }
 318
 319         handles = kvmalloc_array(job->bo_count, sizeof(u32), 
GFP_KERNEL);
 320         if (!handles) {
 321                 ret = -ENOMEM;
 322                 DRM_DEBUG("Failed to allocate incoming GEM 
handles\n");
 323                 goto fail;
 324         }


Regards,
Harshit