On 11/24/21 13:44, Christian König wrote:
Keep track for which BO a resource was allocated.
This is necessary to move the LRU handling into the resources.
A bit problematic is i915 since it tries to use the resource
interface without a BO which is illegal from the conceptional
point of view.
s/conceptional/conceptual/ ?
Can't find the i915 workaround below? Was this the mock bo that was used
in the selftest code, perhaps that was replaced with allowing
resource->bo to be NULL. In that case the commit message should be updated.
/Thomas.
v2: Document that this is a weak reference and add a workaround for i915
v3: further document that this is protected by ttm_device::lru_lock and
clarify the i915 workaround
Signed-off-by: Christian König <christian.koenig@xxxxxxx>
---
drivers/gpu/drm/ttm/ttm_bo_util.c | 7 +++++--
drivers/gpu/drm/ttm/ttm_resource.c | 9 +++++++++
include/drm/ttm/ttm_resource.h | 4 ++++
3 files changed, 18 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c
index 95de2691ee7c..a2e3a9626198 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_util.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
@@ -237,6 +237,11 @@ static int ttm_buffer_object_transfer(struct ttm_buffer_object *bo,
if (bo->type != ttm_bo_type_sg)
fbo->base.base.resv = &fbo->base.base._resv;
+ if (fbo->base.resource) {
+ ttm_resource_set_bo(fbo->base.resource, &fbo->base);
+ bo->resource = NULL;
+ }
+
dma_resv_init(&fbo->base.base._resv);
fbo->base.base.dev = NULL;
ret = dma_resv_trylock(&fbo->base.base._resv);
@@ -512,7 +517,6 @@ static int ttm_bo_move_to_ghost(struct ttm_buffer_object *bo,
ghost_obj->ttm = NULL;
else
bo->ttm = NULL;
- bo->resource = NULL;
dma_resv_unlock(&ghost_obj->base._resv);
ttm_bo_put(ghost_obj);
@@ -637,7 +641,6 @@ int ttm_bo_pipeline_gutting(struct ttm_buffer_object *bo)
dma_resv_unlock(&ghost->base._resv);
ttm_bo_put(ghost);
bo->ttm = ttm;
- bo->resource = NULL;
ttm_bo_assign_mem(bo, sys_res);
return 0;
diff --git a/drivers/gpu/drm/ttm/ttm_resource.c b/drivers/gpu/drm/ttm/ttm_resource.c
index 41e7bf195168..7fdd58b53c61 100644
--- a/drivers/gpu/drm/ttm/ttm_resource.c
+++ b/drivers/gpu/drm/ttm/ttm_resource.c
@@ -41,6 +41,7 @@ void ttm_resource_init(struct ttm_buffer_object *bo,
res->bus.offset = 0;
res->bus.is_iomem = false;
res->bus.caching = ttm_cached;
+ res->bo = bo;
}
EXPORT_SYMBOL(ttm_resource_init);
@@ -122,6 +123,14 @@ bool ttm_resource_compat(struct ttm_resource *res,
}
EXPORT_SYMBOL(ttm_resource_compat);
+void ttm_resource_set_bo(struct ttm_resource *res,
+ struct ttm_buffer_object *bo)
+{
+ spin_lock(&bo->bdev->lru_lock);
+ res->bo = bo;
+ spin_unlock(&bo->bdev->lru_lock);
+}
+
/**
* ttm_resource_manager_init
*
diff --git a/include/drm/ttm/ttm_resource.h b/include/drm/ttm/ttm_resource.h
index 6bf37383002b..69eea9d6399b 100644
--- a/include/drm/ttm/ttm_resource.h
+++ b/include/drm/ttm/ttm_resource.h
@@ -161,6 +161,7 @@ struct ttm_bus_placement {
* @mem_type: Resource type of the allocation.
* @placement: Placement flags.
* @bus: Placement on io bus accessible to the CPU
+ * @bo: weak reference to the BO, protected by ttm_device::lru_lock
*
* Structure indicating the placement and space resources used by a
* buffer object.
@@ -171,6 +172,7 @@ struct ttm_resource {
uint32_t mem_type;
uint32_t placement;
struct ttm_bus_placement bus;
+ struct ttm_buffer_object *bo;
};
/**
@@ -271,6 +273,8 @@ int ttm_resource_alloc(struct ttm_buffer_object *bo,
void ttm_resource_free(struct ttm_buffer_object *bo, struct ttm_resource **res);
bool ttm_resource_compat(struct ttm_resource *res,
struct ttm_placement *placement);
+void ttm_resource_set_bo(struct ttm_resource *res,
+ struct ttm_buffer_object *bo);
void ttm_resource_manager_init(struct ttm_resource_manager *man,
struct ttm_device *bdev,
