For cached objects we can allocate our pages directly in shmem. This should make it possible(in a later patch) to utilise the existing i915-gem shrinker code for such objects. For now this is still disabled.
Signed-off-by: Matthew Auld matthew.auld@intel.com Cc: Thomas Hellström thomas.hellstrom@linux.intel.com Cc: Christian König christian.koenig@amd.com --- drivers/gpu/drm/i915/gem/i915_gem_object.h | 8 + drivers/gpu/drm/i915/gem/i915_gem_shmem.c | 14 +- drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 214 ++++++++++++++++++--- 3 files changed, 206 insertions(+), 30 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h index 48112b9d76df..561d6bd0a5c9 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_object.h +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h @@ -618,6 +618,14 @@ int i915_gem_object_wait_migration(struct drm_i915_gem_object *obj, bool i915_gem_object_placement_possible(struct drm_i915_gem_object *obj, enum intel_memory_type type);
+struct sg_table *shmem_alloc_st(struct drm_i915_private *i915, + size_t size, struct intel_memory_region *mr, + struct address_space *mapping, + unsigned int max_segment); +void shmem_free_st(struct sg_table *st, struct address_space *mapping, + bool dirty, bool backup); +void __shmem_writeback(size_t size, struct address_space *mapping); + #ifdef CONFIG_MMU_NOTIFIER static inline bool i915_gem_object_is_userptr(struct drm_i915_gem_object *obj) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c index 36b711ae9e28..19e55cc29a15 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c @@ -25,8 +25,8 @@ static void check_release_pagevec(struct pagevec *pvec) cond_resched(); }
-static void shmem_free_st(struct sg_table *st, struct address_space *mapping, - bool dirty, bool backup) +void shmem_free_st(struct sg_table *st, struct address_space *mapping, + bool dirty, bool backup) { struct sgt_iter sgt_iter; struct pagevec pvec; @@ -52,10 +52,10 @@ static void shmem_free_st(struct sg_table *st, struct address_space *mapping, kfree(st); }
-static struct sg_table *shmem_alloc_st(struct drm_i915_private *i915, - size_t size, struct intel_memory_region *mr, - struct address_space *mapping, - unsigned int max_segment) +struct sg_table *shmem_alloc_st(struct drm_i915_private *i915, + size_t size, struct intel_memory_region *mr, + struct address_space *mapping, + unsigned int max_segment) { const unsigned long page_count = size / PAGE_SIZE; unsigned long i; @@ -300,7 +300,7 @@ shmem_truncate(struct drm_i915_gem_object *obj) obj->mm.pages = ERR_PTR(-EFAULT); }
-static void __shmem_writeback(size_t size, struct address_space *mapping) +void __shmem_writeback(size_t size, struct address_space *mapping) { struct writeback_control wbc = { .sync_mode = WB_SYNC_NONE, diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c index aefaf9293005..e60e538afcd9 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c @@ -37,6 +37,9 @@ * @ttm: The base TTM page vector. * @dev: The struct device used for dma mapping and unmapping. * @cached_st: The cached scatter-gather table. + * @obj: The GEM object. Should be valid while we have a valid bo->ttm. + * @filp: The shmem file, if using shmem backend. + * @backup: Swap out the pages when unpopulating, if using shmem backend. * * Note that DMA may be going on right up to the point where the page- * vector is unpopulated in delayed destroy. Hence keep the @@ -48,6 +51,9 @@ struct i915_ttm_tt { struct ttm_tt ttm; struct device *dev; struct sg_table *cached_st; + struct drm_i915_gem_object *obj; + struct file *filp; + bool backup; };
static const struct ttm_place sys_placement_flags = { @@ -167,12 +173,105 @@ i915_ttm_placement_from_obj(const struct drm_i915_gem_object *obj, placement->busy_placement = busy; }
+static int i915_ttm_tt_shmem_populate(struct ttm_device *bdev, + struct ttm_tt *ttm, + struct ttm_operation_ctx *ctx) +{ + struct drm_i915_private *i915 = container_of(bdev, typeof(*i915), bdev); + struct intel_memory_region *mr = i915->mm.regions[INTEL_MEMORY_SYSTEM]; + struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm); + const unsigned int max_segment = i915_sg_segment_size(); + const size_t size = ttm->num_pages << PAGE_SHIFT; + struct drm_i915_gem_object *obj = i915_tt->obj; + struct file *filp = i915_tt->filp; + struct sgt_iter sgt_iter; + struct sg_table *st; + struct page *page; + unsigned long i; + int err; + + GEM_BUG_ON(obj->mm.madv != I915_MADV_WILLNEED); + + if (!filp) { + struct address_space *mapping; + gfp_t mask; + + filp = shmem_file_setup("i915-shmem-tt", size, VM_NORESERVE); + if (IS_ERR(filp)) + return PTR_ERR(filp); + + mask = GFP_HIGHUSER | __GFP_RECLAIMABLE; + + mapping = filp->f_mapping; + mapping_set_gfp_mask(mapping, mask); + GEM_BUG_ON(!(mapping_gfp_mask(mapping) & __GFP_RECLAIM)); + + i915_tt->filp = filp; + } + + st = shmem_alloc_st(i915, size, mr, filp->f_mapping, max_segment); + if (IS_ERR(st)) + return PTR_ERR(st); + + err = dma_map_sg_attrs(i915_tt->dev, + st->sgl, st->nents, + PCI_DMA_BIDIRECTIONAL, + DMA_ATTR_SKIP_CPU_SYNC | + DMA_ATTR_NO_KERNEL_MAPPING | + DMA_ATTR_NO_WARN); + if (err <= 0) { + err = -EINVAL; + goto err_free_st; + } + + i = 0; + for_each_sgt_page(page, sgt_iter, st) + ttm->pages[i++] = page; + + if (ttm->page_flags & TTM_PAGE_FLAG_SWAPPED) + ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED; + + i915_tt->cached_st = st; + return 0; + +err_free_st: + shmem_free_st(st, filp->f_mapping, false, false); + return err; +} + +static void i915_ttm_tt_shmem_unpopulate(struct ttm_tt *ttm) +{ + struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm); + struct drm_i915_gem_object *obj = i915_tt->obj; + bool backup = i915_tt->backup; + + if (obj->mm.madv == I915_MADV_DONTNEED) { + obj->mm.dirty = false; + GEM_BUG_ON(backup); + } + + dma_unmap_sg(i915_tt->dev, i915_tt->cached_st->sgl, + i915_tt->cached_st->nents, + PCI_DMA_BIDIRECTIONAL); + + shmem_free_st(i915_tt->cached_st, + file_inode(i915_tt->filp)->i_mapping, + obj->mm.dirty, backup); + i915_tt->cached_st = NULL; + + obj->mm.dirty = false; + + if (backup) + ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED; +} + static struct ttm_tt *i915_ttm_tt_create(struct ttm_buffer_object *bo, uint32_t page_flags) { struct ttm_resource_manager *man = ttm_manager_type(bo->bdev, bo->resource->mem_type); struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); + enum ttm_caching caching = i915_ttm_select_tt_caching(obj); struct i915_ttm_tt *i915_tt; int ret;
@@ -184,36 +283,60 @@ static struct ttm_tt *i915_ttm_tt_create(struct ttm_buffer_object *bo, man->use_tt) page_flags |= TTM_PAGE_FLAG_ZERO_ALLOC;
- ret = ttm_tt_init(&i915_tt->ttm, bo, page_flags, - i915_ttm_select_tt_caching(obj)); - if (ret) { - kfree(i915_tt); - return NULL; - } + if (i915_gem_object_is_shrinkable(obj) && caching == ttm_cached) + page_flags |= TTM_PAGE_FLAG_SHMEM; + + ret = ttm_tt_init(&i915_tt->ttm, bo, page_flags, caching); + if (ret) + goto err_free;
i915_tt->dev = obj->base.dev->dev; + i915_tt->obj = obj;
return &i915_tt->ttm; + +err_free: + kfree(i915_tt); + return NULL; +} + +static int i915_ttm_tt_populate(struct ttm_device *bdev, + struct ttm_tt *ttm, + struct ttm_operation_ctx *ctx) +{ + struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm); + + if (ttm->page_flags & TTM_PAGE_FLAG_SHMEM) + return i915_ttm_tt_shmem_populate(bdev, ttm, ctx); + + return ttm_pool_alloc(&bdev->pool, ttm, ctx); }
static void i915_ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm) { struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm);
- if (i915_tt->cached_st) { - dma_unmap_sgtable(i915_tt->dev, i915_tt->cached_st, - DMA_BIDIRECTIONAL, 0); - sg_free_table(i915_tt->cached_st); - kfree(i915_tt->cached_st); - i915_tt->cached_st = NULL; + if (ttm->page_flags & TTM_PAGE_FLAG_SHMEM) { + i915_ttm_tt_shmem_unpopulate(ttm); + } else { + if (i915_tt->cached_st) { + dma_unmap_sgtable(i915_tt->dev, i915_tt->cached_st, + DMA_BIDIRECTIONAL, 0); + sg_free_table(i915_tt->cached_st); + kfree(i915_tt->cached_st); + i915_tt->cached_st = NULL; + } + ttm_pool_free(&bdev->pool, ttm); } - ttm_pool_free(&bdev->pool, ttm); }
static void i915_ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *ttm) { struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm);
+ if (i915_tt->filp) + fput(i915_tt->filp); + ttm_tt_fini(ttm); kfree(i915_tt); } @@ -223,6 +346,10 @@ static bool i915_ttm_eviction_valuable(struct ttm_buffer_object *bo, { struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
+ if (place->mem_type == TTM_PL_SYSTEM && + bo->ttm && bo->ttm->page_flags & TTM_PAGE_FLAG_SHMEM) + return false; + /* Will do for now. Our pinned objects are still on TTM's LRU lists */ return i915_gem_object_evictable(obj); } @@ -316,9 +443,11 @@ static void i915_ttm_adjust_gem_after_move(struct drm_i915_gem_object *obj) i915_gem_object_set_cache_coherency(obj, cache_level); }
-static void i915_ttm_purge(struct drm_i915_gem_object *obj) +static void i915_ttm_writeback(struct drm_i915_gem_object *obj) { struct ttm_buffer_object *bo = i915_gem_to_ttm(obj); + struct i915_ttm_tt *i915_tt = + container_of(bo->ttm, typeof(*i915_tt), ttm); struct ttm_operation_ctx ctx = { .interruptible = true, .no_wait_gpu = false, @@ -326,18 +455,52 @@ static void i915_ttm_purge(struct drm_i915_gem_object *obj) struct ttm_placement place = {}; int ret;
- if (obj->mm.madv == __I915_MADV_PURGED) + if (!bo->ttm || !(bo->ttm->page_flags & TTM_PAGE_FLAG_SHMEM)) return;
- /* TTM's purge interface. Note that we might be reentering. */ + i915_tt->backup = true; ret = ttm_bo_validate(bo, &place, &ctx); - if (!ret) { - obj->write_domain = 0; - obj->read_domains = 0; - i915_ttm_adjust_gem_after_move(obj); - i915_ttm_free_cached_io_st(obj); - obj->mm.madv = __I915_MADV_PURGED; + i915_tt->backup = false; + if (ret) + return; + + __shmem_writeback(obj->base.size, i915_tt->filp->f_mapping); +} + +static void i915_ttm_purge(struct drm_i915_gem_object *obj) +{ + struct ttm_buffer_object *bo = i915_gem_to_ttm(obj); + struct ttm_operation_ctx ctx = { + .interruptible = true, + .no_wait_gpu = false, + }; + struct ttm_placement place = {}; + + if (obj->mm.madv == __I915_MADV_PURGED) + return; + + if (ttm_bo_validate(bo, &place, &ctx)) + return; + + if (bo->ttm && bo->ttm->page_flags & TTM_PAGE_FLAG_SHMEM) { + struct i915_ttm_tt *i915_tt = + container_of(bo->ttm, typeof(*i915_tt), ttm); + + GEM_BUG_ON(i915_tt->backup); + + if (i915_tt->filp) { + shmem_truncate_range(file_inode(i915_tt->filp), + 0, (loff_t)-1); + fput(i915_tt->filp); + i915_tt->filp = NULL; + } } + + obj->write_domain = 0; + obj->read_domains = 0; + i915_ttm_adjust_gem_after_move(obj); + i915_ttm_free_cached_io_st(obj); + obj->mm.madv = __I915_MADV_PURGED; }
static void i915_ttm_swap_notify(struct ttm_buffer_object *bo) @@ -605,6 +768,7 @@ static unsigned long i915_ttm_io_mem_pfn(struct ttm_buffer_object *bo,
static struct ttm_device_funcs i915_ttm_bo_driver = { .ttm_tt_create = i915_ttm_tt_create, + .ttm_tt_populate = i915_ttm_tt_populate, .ttm_tt_unpopulate = i915_ttm_tt_unpopulate, .ttm_tt_destroy = i915_ttm_tt_destroy, .eviction_valuable = i915_ttm_eviction_valuable, @@ -678,6 +842,8 @@ static int __i915_ttm_get_pages(struct drm_i915_gem_object *obj, return PTR_ERR(st);
__i915_gem_object_set_pages(obj, st, i915_sg_dma_sizes(st->sgl)); + if (!bo->ttm || !(bo->ttm->page_flags & TTM_PAGE_FLAG_SHMEM)) + i915_gem_object_make_unshrinkable(obj); }
return ret; @@ -874,9 +1040,12 @@ static const struct drm_i915_gem_object_ops i915_gem_ttm_obj_ops = { .get_pages = i915_ttm_get_pages, .put_pages = i915_ttm_put_pages, .truncate = i915_ttm_purge, + .writeback = i915_ttm_writeback, + .adjust_lru = i915_ttm_adjust_lru, .delayed_free = i915_ttm_delayed_free, .migrate = i915_ttm_migrate, + .mmap_offset = i915_ttm_mmap_offset, .mmap_ops = &vm_ops_ttm, }; @@ -918,7 +1087,6 @@ int __i915_gem_ttm_object_init(struct intel_memory_region *mem, drm_gem_private_object_init(&i915->drm, &obj->base, size); i915_gem_object_init(obj, &i915_gem_ttm_obj_ops, &lock_class, flags); i915_gem_object_init_memory_region(obj, mem); - i915_gem_object_make_unshrinkable(obj); INIT_RADIX_TREE(&obj->ttm.get_io_page.radix, GFP_KERNEL | __GFP_NOWARN); mutex_init(&obj->ttm.get_io_page.lock); bo_type = (obj->flags & I915_BO_ALLOC_USER) ? ttm_bo_type_device :