[v3,5/7] drm/i915/ttm: wire up the object offset

Commit Message

Matthew Auld March 14, 2022, 11:28 a.m. UTC

For the ttm backend we can use existing placements fpfn and lpfn to
force the allocator to place the object at the requested offset,
potentially evicting stuff if the spot is currently occupied.

Signed-off-by: Matthew Auld <[e-mail]>
Cc: Thomas Hellström <[e-mail]>
Acked-by: Nirmoy Das <[e-mail]>
---
 .../gpu/drm/i915/gem/i915_gem_object_types.h   |  2 ++
 drivers/gpu/drm/i915/gem/i915_gem_ttm.c        | 18 ++++++++++++++----
 drivers/gpu/drm/i915/i915_ttm_buddy_manager.c  |  3 ++-
 drivers/gpu/drm/i915/intel_region_ttm.c        |  7 ++++++-
 drivers/gpu/drm/i915/intel_region_ttm.h        |  1 +
 drivers/gpu/drm/i915/selftests/mock_region.c   |  3 +++
 6 files changed, 28 insertions(+), 6 deletions(-)

Patch

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
index fd54eb8f4826..2c88bdb8ff7c 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
@@ -631,6 +631,8 @@  struct drm_i915_gem_object {
 
 		struct drm_mm_node *stolen;
 
+		resource_size_t bo_offset;
+
 		unsigned long scratch;
 		u64 encode;
 
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
index 5e543ed867a2..e4a06fcf741a 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
@@ -126,6 +126,8 @@  i915_ttm_select_tt_caching(const struct drm_i915_gem_object *obj)
 static void
 i915_ttm_place_from_region(const struct intel_memory_region *mr,
 			   struct ttm_place *place,
+			   resource_size_t offset,
+			   resource_size_t size,
 			   unsigned int flags)
 {
 	memset(place, 0, sizeof(*place));
@@ -133,7 +135,10 @@  i915_ttm_place_from_region(const struct intel_memory_region *mr,
 
 	if (flags & I915_BO_ALLOC_CONTIGUOUS)
 		place->flags |= TTM_PL_FLAG_CONTIGUOUS;
-	if (mr->io_size && mr->io_size < mr->total) {
+	if (offset != I915_BO_INVALID_OFFSET) {
+		place->fpfn = offset >> PAGE_SHIFT;
+		place->lpfn = place->fpfn + (size >> PAGE_SHIFT);
+	} else if (mr->io_size && mr->io_size < mr->total) {
 		if (flags & I915_BO_ALLOC_GPU_ONLY) {
 			place->flags |= TTM_PL_FLAG_TOPDOWN;
 		} else {
@@ -155,12 +160,14 @@  i915_ttm_placement_from_obj(const struct drm_i915_gem_object *obj,
 
 	placement->num_placement = 1;
 	i915_ttm_place_from_region(num_allowed ? obj->mm.placements[0] :
-				   obj->mm.region, requested, flags);
+				   obj->mm.region, requested, obj->bo_offset,
+				   obj->base.size, flags);
 
 	/* Cache this on object? */
 	placement->num_busy_placement = num_allowed;
 	for (i = 0; i < placement->num_busy_placement; ++i)
-		i915_ttm_place_from_region(obj->mm.placements[i], busy + i, flags);
+		i915_ttm_place_from_region(obj->mm.placements[i], busy + i,
+					   obj->bo_offset, obj->base.size, flags);
 
 	if (num_allowed == 0) {
 		*busy = *requested;
@@ -802,7 +809,8 @@  static int __i915_ttm_migrate(struct drm_i915_gem_object *obj,
 	struct ttm_placement placement;
 	int ret;
 
-	i915_ttm_place_from_region(mr, &requested, flags);
+	i915_ttm_place_from_region(mr, &requested, obj->bo_offset,
+				   obj->base.size, flags);
 	placement.num_placement = 1;
 	placement.num_busy_placement = 1;
 	placement.placement = &requested;
@@ -1159,6 +1167,8 @@  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);
 
+	obj->bo_offset = offset;
+
 	/* Don't put on a region list until we're either locked or fully initialized. */
 	obj->mm.region = mem;
 	INIT_LIST_HEAD(&obj->mm.region_link);
diff --git a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c
index 129f668f21ff..8e4e3f72c1ef 100644
--- a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c
+++ b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c
@@ -71,7 +71,8 @@  static int i915_ttm_buddy_man_alloc(struct ttm_resource_manager *man,
 
 	GEM_BUG_ON(min_page_size < mm->chunk_size);
 
-	if (place->flags & TTM_PL_FLAG_CONTIGUOUS) {
+	if (place->fpfn + bman_res->base.num_pages != place->lpfn &&
+	    place->flags & TTM_PL_FLAG_CONTIGUOUS) {
 		unsigned long pages;
 
 		size = roundup_pow_of_two(size);
diff --git a/drivers/gpu/drm/i915/intel_region_ttm.c b/drivers/gpu/drm/i915/intel_region_ttm.c
index 737ef3f4ab54..62ff77445b01 100644
--- a/drivers/gpu/drm/i915/intel_region_ttm.c
+++ b/drivers/gpu/drm/i915/intel_region_ttm.c
@@ -12,6 +12,7 @@ 
 
 #include "intel_region_ttm.h"
 
+#include "gem/i915_gem_region.h"
 #include "gem/i915_gem_ttm.h" /* For the funcs/ops export only */
 /**
  * DOC: TTM support structure
@@ -191,6 +192,7 @@  intel_region_ttm_resource_to_rsgt(struct intel_memory_region *mem,
  */
 struct ttm_resource *
 intel_region_ttm_resource_alloc(struct intel_memory_region *mem,
+				resource_size_t offset,
 				resource_size_t size,
 				unsigned int flags)
 {
@@ -202,7 +204,10 @@  intel_region_ttm_resource_alloc(struct intel_memory_region *mem,
 
 	if (flags & I915_BO_ALLOC_CONTIGUOUS)
 		place.flags |= TTM_PL_FLAG_CONTIGUOUS;
-	if (mem->io_size && mem->io_size < mem->total) {
+	if (offset != I915_BO_INVALID_OFFSET) {
+		place.fpfn = offset >> PAGE_SHIFT;
+		place.lpfn = place.fpfn + (size >> PAGE_SHIFT);
+	} else if (mem->io_size && mem->io_size < mem->total) {
 		if (flags & I915_BO_ALLOC_GPU_ONLY) {
 			place.flags |= TTM_PL_FLAG_TOPDOWN;
 		} else {
diff --git a/drivers/gpu/drm/i915/intel_region_ttm.h b/drivers/gpu/drm/i915/intel_region_ttm.h
index fdee5e7bd46c..cf9d86dcf409 100644
--- a/drivers/gpu/drm/i915/intel_region_ttm.h
+++ b/drivers/gpu/drm/i915/intel_region_ttm.h
@@ -36,6 +36,7 @@  struct ttm_device_funcs *i915_ttm_driver(void);
 #ifdef CONFIG_DRM_I915_SELFTEST
 struct ttm_resource *
 intel_region_ttm_resource_alloc(struct intel_memory_region *mem,
+				resource_size_t offset,
 				resource_size_t size,
 				unsigned int flags);
 #endif
diff --git a/drivers/gpu/drm/i915/selftests/mock_region.c b/drivers/gpu/drm/i915/selftests/mock_region.c
index f16c0b7198c7..670557ce1024 100644
--- a/drivers/gpu/drm/i915/selftests/mock_region.c
+++ b/drivers/gpu/drm/i915/selftests/mock_region.c
@@ -26,6 +26,7 @@  static int mock_region_get_pages(struct drm_i915_gem_object *obj)
 	int err;
 
 	obj->mm.res = intel_region_ttm_resource_alloc(obj->mm.region,
+						      obj->bo_offset,
 						      obj->base.size,
 						      obj->flags);
 	if (IS_ERR(obj->mm.res))
@@ -71,6 +72,8 @@  static int mock_object_init(struct intel_memory_region *mem,
 	drm_gem_private_object_init(&i915->drm, &obj->base, size);
 	i915_gem_object_init(obj, &mock_region_obj_ops, &lock_class, flags);
 
+	obj->bo_offset = offset;
+
 	obj->read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
 
 	i915_gem_object_set_cache_coherency(obj, I915_CACHE_NONE);