Commit 69013f52 authored by Alice Ryhl's avatar Alice Ryhl Committed by Danilo Krummrich
Browse files

panthor: use drm_gem_object.gpuva.lock instead of gpuva_list_lock 



Now that drm_gem_object has a dedicated mutex for the gpuva list that is
intended to be used in cases that must be fence signalling safe, use it
in Panthor.

Reviewed-by: default avatarBoris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: default avatarAlice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250827-gpuva-mutex-in-gem-v3-2-bd89f5a82c0d@google.com


Signed-off-by: default avatarDanilo Krummrich <dakr@kernel.org>
parent e7fa80e2

drivers/gpu/drm/panthor/panthor_gem.c

+1 −3
Original line number Diff line number Diff line
@@ -74,7 +74,6 @@ static void panthor_gem_free_object(struct drm_gem_object *obj) 
	mutex_destroy(&bo->label.lock);



	drm_gem_free_mmap_offset(&bo->base.base);

	mutex_destroy(&bo->gpuva_list_lock);

	drm_gem_shmem_free(&bo->base);

	drm_gem_object_put(vm_root_gem);

}
@@ -246,8 +245,7 @@ struct drm_gem_object *panthor_gem_create_object(struct drm_device *ddev, size_t 


	obj->base.base.funcs = &panthor_gem_funcs;

	obj->base.map_wc = !ptdev->coherent;

	mutex_init(&obj->gpuva_list_lock);

	drm_gem_gpuva_set_lock(&obj->base.base, &obj->gpuva_list_lock);

	drm_gem_gpuva_set_lock(&obj->base.base, &obj->base.base.gpuva.lock);

	mutex_init(&obj->label.lock);



	panthor_gem_debugfs_bo_init(obj);

drivers/gpu/drm/panthor/panthor_gem.h

+0 −12
Original line number Diff line number Diff line
@@ -79,18 +79,6 @@ struct panthor_gem_object { 
	 */

	struct drm_gem_object *exclusive_vm_root_gem;



	/**

	 * @gpuva_list_lock: Custom GPUVA lock.

	 *

	 * Used to protect insertion of drm_gpuva elements to the

	 * drm_gem_object.gpuva.list list.

	 *

	 * We can't use the GEM resv for that, because drm_gpuva_link() is

	 * called in a dma-signaling path, where we're not allowed to take

	 * resv locks.

	 */

	struct mutex gpuva_list_lock;



	/** @flags: Combination of drm_panthor_bo_flags flags. */

	u32 flags;

drivers/gpu/drm/panthor/panthor_mmu.c

+8 −8
Original line number Diff line number Diff line
@@ -1107,9 +1107,9 @@ static void panthor_vm_bo_put(struct drm_gpuvm_bo *vm_bo) 
	 * GEM vm_bo list.

	 */

	dma_resv_lock(drm_gpuvm_resv(vm), NULL);

	mutex_lock(&bo->gpuva_list_lock);

	mutex_lock(&bo->base.base.gpuva.lock);

	unpin = drm_gpuvm_bo_put(vm_bo);

	mutex_unlock(&bo->gpuva_list_lock);

	mutex_unlock(&bo->base.base.gpuva.lock);

	dma_resv_unlock(drm_gpuvm_resv(vm));



	/* If the vm_bo object was destroyed, release the pin reference that
@@ -1282,9 +1282,9 @@ static int panthor_vm_prepare_map_op_ctx(struct panthor_vm_op_ctx *op_ctx, 
	 * calling this function.

	 */

	dma_resv_lock(panthor_vm_resv(vm), NULL);

	mutex_lock(&bo->gpuva_list_lock);

	mutex_lock(&bo->base.base.gpuva.lock);

	op_ctx->map.vm_bo = drm_gpuvm_bo_obtain_prealloc(preallocated_vm_bo);

	mutex_unlock(&bo->gpuva_list_lock);

	mutex_unlock(&bo->base.base.gpuva.lock);

	dma_resv_unlock(panthor_vm_resv(vm));



	/* If the a vm_bo for this <VM,BO> combination exists, it already
@@ -2036,10 +2036,10 @@ static void panthor_vma_link(struct panthor_vm *vm, 
{

	struct panthor_gem_object *bo = to_panthor_bo(vma->base.gem.obj);



	mutex_lock(&bo->gpuva_list_lock);

	mutex_lock(&bo->base.base.gpuva.lock);

	drm_gpuva_link(&vma->base, vm_bo);

	drm_WARN_ON(&vm->ptdev->base, drm_gpuvm_bo_put(vm_bo));

	mutex_unlock(&bo->gpuva_list_lock);

	mutex_unlock(&bo->base.base.gpuva.lock);

}



static void panthor_vma_unlink(struct panthor_vm *vm,
@@ -2048,9 +2048,9 @@ static void panthor_vma_unlink(struct panthor_vm *vm, 
	struct panthor_gem_object *bo = to_panthor_bo(vma->base.gem.obj);

	struct drm_gpuvm_bo *vm_bo = drm_gpuvm_bo_get(vma->base.vm_bo);



	mutex_lock(&bo->gpuva_list_lock);

	mutex_lock(&bo->base.base.gpuva.lock);

	drm_gpuva_unlink(&vma->base);

	mutex_unlock(&bo->gpuva_list_lock);

	mutex_unlock(&bo->base.base.gpuva.lock);



	/* drm_gpuva_unlink() release the vm_bo, but we manually retained it

	 * when entering this function, so we can implement deferred VMA