On Mon, Dec 14, 2015 at 11:16:10AM +0530, [email protected] wrote:
> +static int
> +copy_content(struct drm_i915_gem_object *obj,
> + struct drm_i915_private *i915,
> + struct address_space *mapping)
> +{
> + struct drm_mm_node node;
> + int ret, i;
> +
> + /* stolen objects are already pinned to prevent shrinkage */
> + memset(&node, 0, sizeof(node));
> + ret = i915_gem_insert_node_in_range(i915, &node, 4096, 0,
> + 0, i915->gtt.mappable_end);
> + if (ret)
> + return ret;
> +
> + for (i = 0; i < obj->base.size / PAGE_SIZE; i++) {
> + struct page *page;
> + void *__iomem src;
> + void *dst;
> +
> + wmb();
> + i915->gtt.base.insert_page(&i915->gtt.base,
> + i915_gem_object_get_dma_address(obj,
> i),
> + node.start,
> + I915_CACHE_NONE,
> + 0);
> + wmb();
> +
> + page = shmem_read_mapping_page(mapping, i);
> + if (IS_ERR(page)) {
> + ret = PTR_ERR(page);
> + break;
> + }
> +
> + src = io_mapping_map_atomic_wc(i915->gtt.mappable, node.start);
> + dst = kmap_atomic(page);
The wmb() barriers are here...
> + memcpy_fromio(dst, src, PAGE_SIZE);
...and here.
> + kunmap_atomic(dst);
> + io_mapping_unmap_atomic(src);
> +
> + page_cache_release(page);
> + }
> +
> + wmb();
> + i915->gtt.base.clear_range(&i915->gtt.base,
> + node.start, node.size,
> + true);
> + drm_mm_remove_node(&node);
> + return ret;
> +}
> +
> +/**
> + * i915_gem_object_migrate_stolen_to_shmemfs() - migrates a stolen backed
> + * object to shmemfs
> + * @obj: stolen backed object to be migrated
> + *
> + * Returns: 0 on successful migration, errno on failure
> + */
> +
> +static int
> +i915_gem_object_migrate_stolen_to_shmemfs(struct drm_i915_gem_object *obj)
> +{
> + struct drm_i915_private *i915 = to_i915(obj->base.dev);
> + struct i915_vma *vma, *vn;
> + struct file *file;
> + struct address_space *mapping;
> + struct sg_table *stolen_pages, *shmemfs_pages;
> + int ret;
> +
> + if (WARN_ON_ONCE(i915_gem_object_needs_bit17_swizzle(obj)))
> + return -EINVAL;
> +
> + ret = i915_gem_object_set_to_gtt_domain(obj, false);
> + if (ret)
> + return ret;
This should be in copy_content.
> + file = shmem_file_setup("drm mm object", obj->base.size, VM_NORESERVE);
> + if (IS_ERR(file))
> + return PTR_ERR(file);
> + mapping = i915_gem_set_inode_gfp(obj->base.dev, file);
> +
> + list_for_each_entry_safe(vma, vn, &obj->vma_list, vma_link)
> + if (i915_vma_unbind(vma))
> + continue;
> +
> + if (obj->madv != I915_MADV_WILLNEED && list_empty(&obj->vma_list)) {
> + /* Discard the stolen reservation, and replace with
> + * an unpopulated shmemfs object.
> + */
> + obj->madv = __I915_MADV_PURGED;
> + goto swap_pages;
A goto over one line? else?
> + }
> +
> + ret = copy_content(obj, i915, mapping);
> + if (ret)
> + goto err_file;
> +
> +swap_pages:
> + stolen_pages = obj->pages;
> + obj->pages = NULL;
> +
> + obj->base.filp = file;
> + obj->base.read_domains = I915_GEM_DOMAIN_CPU;
> + obj->base.write_domain = I915_GEM_DOMAIN_CPU;
Again, these domains are a result of copy_content.
> +
> + /* Recreate any pinned binding with pointers to the new storage */
> + if (!list_empty(&obj->vma_list)) {
> + ret = i915_gem_object_get_pages_gtt(obj);
> + if (ret) {
> + obj->pages = stolen_pages;
> + goto err_file;
> + }
> +
> + ret = i915_gem_object_set_to_gtt_domain(obj, true);
Why? The pages are allocated, the domain is irrelevant (just so long as
it is accurate, see above).
> + obj->get_page.sg = obj->pages->sgl;
> + obj->get_page.last = 0;
> +
> + list_for_each_entry(vma, &obj->vma_list, vma_link) {
> + if (!drm_mm_node_allocated(&vma->node))
> + continue;
> +
> + WARN_ON(i915_vma_bind(vma,
> + obj->cache_level,
> + PIN_UPDATE));
> + }
> + } else
> + list_del(&obj->global_list);
This is very confusing (and wrong). This should only be a result of
setting PURGED above.
> + /* drop the stolen pin and backing */
> + shmemfs_pages = obj->pages;
> + obj->pages = stolen_pages;
> +
> + i915_gem_object_unpin_pages(obj);
> + obj->ops->put_pages(obj);
> + if (obj->ops->release)
> + obj->ops->release(obj);
> +
> + obj->ops = &i915_gem_object_ops;
> + obj->pages = shmemfs_pages;
> +
> + return 0;
> +
> +err_file:
> + fput(file);
> + obj->base.filp = NULL;
> + return ret;
> +}
> +
> +int
> +i915_gem_freeze(struct drm_device *dev)
> +{
> + /* Called before i915_gem_suspend() when hibernating */
> + struct drm_i915_private *i915 = to_i915(dev);
> + struct drm_i915_gem_object *obj, *tmp;
> + struct list_head *phase[] = {
> + &i915->mm.unbound_list, &i915->mm.bound_list, NULL
> + }, **p;
> + int ret;
> +
> + ret = i915_mutex_lock_interruptible(dev);
> + if (ret)
> + return ret;
Whitespace.
-Chris
> + /* Across hibernation, the stolen area is not preserved.
> + * Anything inside stolen must copied back to normal
> + * memory if we wish to preserve it.
> + */
--
Chris Wilson, Intel Open Source Technology Centre
_______________________________________________
Intel-gfx mailing list
[email protected]
http://lists.freedesktop.org/mailman/listinfo/intel-gfx
