Re: [Intel-xe] [PATCH v2 07/31] drm/xe: Only try to lock external BOs in VM bind

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Mon, May 08, 2023 at 01:08:10AM +0000, Matthew Brost wrote:
> On Fri, May 05, 2023 at 02:40:40PM -0400, Rodrigo Vivi wrote:
> > On Mon, May 01, 2023 at 05:17:03PM -0700, Matthew Brost wrote:
> > > Not needed and causes some issues with bulk LRU moves.
> > 
> > I'm confused with this explanation and the code below.
> > could you please provide a bit more wording here?
> > 
> 
> We only need to try to lock a BO if it external as non-external BOs
> share the dma-resv with the already locked VM. Trying to lock
> non-external BOs caused an issue (list corruption) in an uncoming patch
> which adds bulk LRU move. Since this code isn't needed, remove it.

it makes more sense now. with this in commit msg (but with Christopher fix)


Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>


> 
> ^^^ How about this.
> 
> > > 
> > > Signed-off-by: Matthew Brost <mattthew.brost@intel.com>
> > > ---
> > >  drivers/gpu/drm/xe/xe_vm.c | 8 +++++---
> > >  1 file changed, 5 insertions(+), 3 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
> > > index 272f0f7f24fe..6c427ff92c44 100644
> > > --- a/drivers/gpu/drm/xe/xe_vm.c
> > > +++ b/drivers/gpu/drm/xe/xe_vm.c
> > > @@ -2064,9 +2064,11 @@ static int vm_bind_ioctl(struct xe_vm *vm, struct xe_vma *vma,
> > >  		 */
> > >  		xe_bo_get(vbo);
> > >  
> > > -		tv_bo.bo = &vbo->ttm;
> > > -		tv_bo.num_shared = 1;
> > > -		list_add(&tv_bo.head, &objs);
> > > +		if (!vbo->vm) {
> > > +			tv_bo.bo = &vbo->ttm;
> > > +			tv_bo.num_shared = 1;
> > > +			list_add(&tv_bo.head, &objs);
> > > +		}
> > >  	}
> > >  
> > >  again:
> > > -- 
> > > 2.34.1
> > >