[PATCH v3 01/30] drm/xe: Retry BO allocation

[Summers, Stuart]

On Tue, 2024-12-17 at 15:33 -0800, Matthew Brost wrote:
> TTM doesn't support fair eviction via WW locking, this mitigated in
> by
> using retry loops in exec and preempt rebind worker. Extend this
> retry
> loop to BO allocation. Once TTM supports fair eviction this patch can
> be
> reverted.
> 
> Signed-off-by: Matthew Brost <matthew.brost at intel.com>
> ---
>  drivers/gpu/drm/xe/xe_bo.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c
> index e6c896ad5602..a670a0444e03 100644
> --- a/drivers/gpu/drm/xe/xe_bo.c
> +++ b/drivers/gpu/drm/xe/xe_bo.c
> @@ -2142,6 +2142,7 @@ int xe_gem_create_ioctl(struct drm_device *dev,
> void *data,
>         struct xe_file *xef = to_xe_file(file);
>         struct drm_xe_gem_create *args = data;
>         struct xe_vm *vm = NULL;
> +       ktime_t end = 0;
>         struct xe_bo *bo;
>         unsigned int bo_flags;
>         u32 handle;
> @@ -2214,11 +2215,14 @@ int xe_gem_create_ioctl(struct drm_device
> *dev, void *data,
>                 vm = xe_vm_lookup(xef, args->vm_id);
>                 if (XE_IOCTL_DBG(xe, !vm))
>                         return -ENOENT;
> +       }
> +
> +retry:
> +       if (vm) {
>                 err = xe_vm_lock(vm, true);
>                 if (err)
>                         goto out_vm;
>         }
> -

Feel like we could keep this line break, but not a blocker. Looks good,
thanks!

Reviewed-by: Stuart Summers <stuart.summers at intel.com>

>         bo = xe_bo_create_user(xe, NULL, vm, args->size, args-
> >cpu_caching,
>                                bo_flags);
>  
> @@ -2227,6 +2231,8 @@ int xe_gem_create_ioctl(struct drm_device *dev,
> void *data,
>  
>         if (IS_ERR(bo)) {
>                 err = PTR_ERR(bo);
> +               if (xe_vm_validate_should_retry(NULL, err, &end))
> +                       goto retry;
>                 goto out_vm;
>         }
>