On Mon, 29 Nov 2021 at 13:58, Maarten Lankhorst
<maarten.lankhorst@xxxxxxxxxxxxxxx> wrote:
>
> i915_gem_execbuf will call i915_gem_evict_vm() after failing to pin
> all objects in the first round. We are about to remove those short-term
> pins, but even without those the objects are still locked. Add a special
> case to allow i915_gem_evict_vm to evict locked objects as well.
>
> This might also allow multiple objects sharing the same resv to be evicted.
>
> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
Reviewed-by: Matthew Auld <matthew.auld@xxxxxxxxx>
Do we need similar treatment for stuff like evict_for_node etc?
> ---
> drivers/gpu/drm/i915/i915_gem_evict.c | 23 ++++++++++++++++++++++-
> 1 file changed, 22 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_gem_evict.c b/drivers/gpu/drm/i915/i915_gem_evict.c
> index 24f5e3345e43..f502a617b35c 100644
> --- a/drivers/gpu/drm/i915/i915_gem_evict.c
> +++ b/drivers/gpu/drm/i915/i915_gem_evict.c
> @@ -410,21 +410,42 @@ int i915_gem_evict_vm(struct i915_address_space *vm, struct i915_gem_ww_ctx *ww)
> do {
> struct i915_vma *vma, *vn;
> LIST_HEAD(eviction_list);
> + LIST_HEAD(locked_eviction_list);
>
> list_for_each_entry(vma, &vm->bound_list, vm_link) {
> if (i915_vma_is_pinned(vma))
> continue;
>
> + /*
> + * If we already own the lock, trylock fails. In case the resv
> + * is shared among multiple objects, we still need the object ref.
> + */
> + if (ww && (dma_resv_locking_ctx(vma->obj->base.resv) == &ww->ctx)) {
> + __i915_vma_pin(vma);
> + list_add(&vma->evict_link, &locked_eviction_list);
> + continue;
> + }
> +
> if (!i915_gem_object_trylock(vma->obj, ww))
> continue;
>
> __i915_vma_pin(vma);
> list_add(&vma->evict_link, &eviction_list);
> }
> - if (list_empty(&eviction_list))
> + if (list_empty(&eviction_list) && list_empty(&locked_eviction_list))
> break;
>
> ret = 0;
> + /* Unbind locked objects first, before unlocking the eviction_list */
> + list_for_each_entry_safe(vma, vn, &locked_eviction_list, evict_link) {
> + __i915_vma_unpin(vma);
> +
> + if (ret == 0)
> + ret = __i915_vma_unbind(vma);
> + if (ret != -EINTR) /* "Get me out of here!" */
> + ret = 0;
> + }
> +
> list_for_each_entry_safe(vma, vn, &eviction_list, evict_link) {
> __i915_vma_unpin(vma);
> if (ret == 0)
> --
> 2.34.0
>
