In order to keep the assert_bind_count() valid, we need to hold the vma page reference until after we drop the bind count. However, we must also keep the drm_mm_remove_node() as the last action of i915_vma_unbind() so that it serialises with the unlocked check inside i915_vma_destroy(). So we need to split up i915_vma_remove() so that we order the detach, drop pages and remove as required during unbind.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=112067 Signed-off-by: Chris Wilson <[email protected]> Cc: Matthew Auld <[email protected]> --- drivers/gpu/drm/i915/i915_vma.c | 37 +++++++++++++++------------------ 1 file changed, 17 insertions(+), 20 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c index d733bcf262f0..e5512f26e20a 100644 --- a/drivers/gpu/drm/i915/i915_vma.c +++ b/drivers/gpu/drm/i915/i915_vma.c @@ -700,41 +700,35 @@ i915_vma_insert(struct i915_vma *vma, u64 size, u64 alignment, u64 flags) GEM_BUG_ON(!drm_mm_node_allocated(&vma->node)); GEM_BUG_ON(!i915_gem_valid_gtt_space(vma, color)); - list_add_tail(&vma->vm_link, &vma->vm->bound_list); - if (vma->obj) { - atomic_inc(&vma->obj->bind_count); - assert_bind_count(vma->obj); + struct drm_i915_gem_object *obj = vma->obj; + + atomic_inc(&obj->bind_count); + assert_bind_count(obj); } + list_add_tail(&vma->vm_link, &vma->vm->bound_list); return 0; } static void -i915_vma_remove(struct i915_vma *vma) +i915_vma_detach(struct i915_vma *vma) { GEM_BUG_ON(!drm_mm_node_allocated(&vma->node)); GEM_BUG_ON(i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND)); - list_del(&vma->vm_link); - /* - * Since the unbound list is global, only move to that list if - * no more VMAs exist. + * And finally now the object is completely decoupled from this + * vma, we can drop its hold on the backing storage and allow + * it to be reaped by the shrinker. */ + list_del(&vma->vm_link); if (vma->obj) { struct drm_i915_gem_object *obj = vma->obj; - /* - * And finally now the object is completely decoupled from this - * vma, we can drop its hold on the backing storage and allow - * it to be reaped by the shrinker. - */ - atomic_dec(&obj->bind_count); assert_bind_count(obj); + atomic_dec(&obj->bind_count); } - - drm_mm_remove_node(&vma->node); } static bool try_qad_pin(struct i915_vma *vma, unsigned int flags) @@ -929,8 +923,10 @@ int i915_vma_pin(struct i915_vma *vma, u64 size, u64 alignment, u64 flags) GEM_BUG_ON(i915_vma_misplaced(vma, size, alignment, flags)); err_remove: - if (!i915_vma_is_bound(vma, I915_VMA_BIND_MASK)) - i915_vma_remove(vma); + if (!i915_vma_is_bound(vma, I915_VMA_BIND_MASK)) { + i915_vma_detach(vma); + drm_mm_remove_node(&vma->node); + } err_active: i915_active_release(&vma->active); err_unlock: @@ -1187,9 +1183,10 @@ int __i915_vma_unbind(struct i915_vma *vma) } atomic_and(~(I915_VMA_BIND_MASK | I915_VMA_ERROR), &vma->flags); + i915_vma_detach(vma); vma_unbind_pages(vma); - i915_vma_remove(vma); + drm_mm_remove_node(&vma->node); /* pairs with i915_vma_destroy() */ return 0; } -- 2.24.0.rc1 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
