Re: [PATCH v4 3/4] drm/panthor: Label all kernel BO's

[Boris Brezillon <boris.brezillon@collabora.com>]

On Wed,  2 Apr 2025 12:54:28 +0100
Adrián Larumbe <adrian.larumbe@collabora.com> wrote:

> Kernel BO's aren't exposed to UM, so labelling them is the responsibility
> of the driver itself. This kind of tagging will prove useful in further
> commits when want to expose these objects through DebugFS.
> 
> Expand panthor_kernel_bo_create() interface to take a NULL-terminated
> string. No bounds checking is done because all label strings are given
> as statically-allocated literals, but if a more complex kernel BO naming
> scheme with explicit memory allocation and formatting was desired in the
> future, this would have to change.
> 
> Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
> ---
>  drivers/gpu/drm/panthor/panthor_fw.c    | 8 +++++---
>  drivers/gpu/drm/panthor/panthor_gem.c   | 3 ++-
>  drivers/gpu/drm/panthor/panthor_gem.h   | 2 +-
>  drivers/gpu/drm/panthor/panthor_heap.c  | 6 ++++--
>  drivers/gpu/drm/panthor/panthor_sched.c | 9 ++++++---
>  5 files changed, 18 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panthor/panthor_fw.c b/drivers/gpu/drm/panthor/panthor_fw.c
> index 4a9c4afa9ad7..36e60bb2dcc5 100644
> --- a/drivers/gpu/drm/panthor/panthor_fw.c
> +++ b/drivers/gpu/drm/panthor/panthor_fw.c
> @@ -449,7 +449,8 @@ panthor_fw_alloc_queue_iface_mem(struct panthor_device *ptdev,
>  				       DRM_PANTHOR_BO_NO_MMAP,
>  				       DRM_PANTHOR_VM_BIND_OP_MAP_NOEXEC |
>  				       DRM_PANTHOR_VM_BIND_OP_MAP_UNCACHED,
> -				       PANTHOR_VM_KERNEL_AUTO_VA);
> +				       PANTHOR_VM_KERNEL_AUTO_VA,
> +				       "Queue FW interface");
>  	if (IS_ERR(mem))
>  		return mem;
>  
> @@ -481,7 +482,8 @@ panthor_fw_alloc_suspend_buf_mem(struct panthor_device *ptdev, size_t size)
>  	return panthor_kernel_bo_create(ptdev, panthor_fw_vm(ptdev), size,
>  					DRM_PANTHOR_BO_NO_MMAP,
>  					DRM_PANTHOR_VM_BIND_OP_MAP_NOEXEC,
> -					PANTHOR_VM_KERNEL_AUTO_VA);
> +					PANTHOR_VM_KERNEL_AUTO_VA,
> +					"FW suspend buffer");
>  }
>  
>  static int panthor_fw_load_section_entry(struct panthor_device *ptdev,
> @@ -601,7 +603,7 @@ static int panthor_fw_load_section_entry(struct panthor_device *ptdev,
>  		section->mem = panthor_kernel_bo_create(ptdev, panthor_fw_vm(ptdev),
>  							section_size,
>  							DRM_PANTHOR_BO_NO_MMAP,
> -							vm_map_flags, va);
> +							vm_map_flags, va, "FW Section");

nit: Let's try to use the caps consistently in the names we assign to
kernel BOs, like, cap on the first word only, or cap on each word, I
don't mind, but pick one and try to stick to it.

>  		if (IS_ERR(section->mem))
>  			return PTR_ERR(section->mem);
>  
> diff --git a/drivers/gpu/drm/panthor/panthor_gem.c b/drivers/gpu/drm/panthor/panthor_gem.c
> index 7d017f9d1d52..44d027e6d664 100644
> --- a/drivers/gpu/drm/panthor/panthor_gem.c
> +++ b/drivers/gpu/drm/panthor/panthor_gem.c
> @@ -81,7 +81,7 @@ void panthor_kernel_bo_destroy(struct panthor_kernel_bo *bo)
>  struct panthor_kernel_bo *
>  panthor_kernel_bo_create(struct panthor_device *ptdev, struct panthor_vm *vm,
>  			 size_t size, u32 bo_flags, u32 vm_map_flags,
> -			 u64 gpu_va)
> +			 u64 gpu_va, const char *name)
>  {
>  	struct drm_gem_shmem_object *obj;
>  	struct panthor_kernel_bo *kbo;
> @@ -105,6 +105,7 @@ panthor_kernel_bo_create(struct panthor_device *ptdev, struct panthor_vm *vm,
>  	kbo->obj = &obj->base;
>  	bo->flags = bo_flags;
>  
> +	panthor_gem_kernel_bo_set_label(kbo, name);

nit: can we add a blank line here, and remove the one that's after the
bo->flags assignment?

>  	/* The system and GPU MMU page size might differ, which becomes a
>  	 * problem for FW sections that need to be mapped at explicit address
>  	 * since our PAGE_SIZE alignment might cover a VA range that's
> diff --git a/drivers/gpu/drm/panthor/panthor_gem.h b/drivers/gpu/drm/panthor/panthor_gem.h
> index e18fbc093abd..49daa5088a0d 100644
> --- a/drivers/gpu/drm/panthor/panthor_gem.h
> +++ b/drivers/gpu/drm/panthor/panthor_gem.h
> @@ -153,7 +153,7 @@ panthor_kernel_bo_vunmap(struct panthor_kernel_bo *bo)
>  struct panthor_kernel_bo *
>  panthor_kernel_bo_create(struct panthor_device *ptdev, struct panthor_vm *vm,
>  			 size_t size, u32 bo_flags, u32 vm_map_flags,
> -			 u64 gpu_va);
> +			 u64 gpu_va, const char *name);
>  
>  void panthor_kernel_bo_destroy(struct panthor_kernel_bo *bo);
>  
> diff --git a/drivers/gpu/drm/panthor/panthor_heap.c b/drivers/gpu/drm/panthor/panthor_heap.c
> index db0285ce5812..ad122bd37ac2 100644
> --- a/drivers/gpu/drm/panthor/panthor_heap.c
> +++ b/drivers/gpu/drm/panthor/panthor_heap.c
> @@ -147,7 +147,8 @@ static int panthor_alloc_heap_chunk(struct panthor_device *ptdev,
>  	chunk->bo = panthor_kernel_bo_create(ptdev, vm, heap->chunk_size,
>  					     DRM_PANTHOR_BO_NO_MMAP,
>  					     DRM_PANTHOR_VM_BIND_OP_MAP_NOEXEC,
> -					     PANTHOR_VM_KERNEL_AUTO_VA);
> +					     PANTHOR_VM_KERNEL_AUTO_VA,
> +					     "Tiler heap chunk");
>  	if (IS_ERR(chunk->bo)) {
>  		ret = PTR_ERR(chunk->bo);
>  		goto err_free_chunk;
> @@ -550,7 +551,8 @@ panthor_heap_pool_create(struct panthor_device *ptdev, struct panthor_vm *vm)
>  	pool->gpu_contexts = panthor_kernel_bo_create(ptdev, vm, bosize,
>  						      DRM_PANTHOR_BO_NO_MMAP,
>  						      DRM_PANTHOR_VM_BIND_OP_MAP_NOEXEC,
> -						      PANTHOR_VM_KERNEL_AUTO_VA);
> +						      PANTHOR_VM_KERNEL_AUTO_VA,
> +						      "Heap pool");
>  	if (IS_ERR(pool->gpu_contexts)) {
>  		ret = PTR_ERR(pool->gpu_contexts);
>  		goto err_destroy_pool;
> diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c
> index 1a276db095ff..a0b8f1ba4ea8 100644
> --- a/drivers/gpu/drm/panthor/panthor_sched.c
> +++ b/drivers/gpu/drm/panthor/panthor_sched.c
> @@ -3334,7 +3334,8 @@ group_create_queue(struct panthor_group *group,
>  						  DRM_PANTHOR_BO_NO_MMAP,
>  						  DRM_PANTHOR_VM_BIND_OP_MAP_NOEXEC |
>  						  DRM_PANTHOR_VM_BIND_OP_MAP_UNCACHED,
> -						  PANTHOR_VM_KERNEL_AUTO_VA);
> +						  PANTHOR_VM_KERNEL_AUTO_VA,
> +						  "Ring buffer");
>  	if (IS_ERR(queue->ringbuf)) {
>  		ret = PTR_ERR(queue->ringbuf);
>  		goto err_free_queue;
> @@ -3364,7 +3365,8 @@ group_create_queue(struct panthor_group *group,
>  					 DRM_PANTHOR_BO_NO_MMAP,
>  					 DRM_PANTHOR_VM_BIND_OP_MAP_NOEXEC |
>  					 DRM_PANTHOR_VM_BIND_OP_MAP_UNCACHED,
> -					 PANTHOR_VM_KERNEL_AUTO_VA);
> +					 PANTHOR_VM_KERNEL_AUTO_VA,
> +					 "fdinfo slots");

I think I'd prefer "Group job stats", just in case we end up dumping
other stuff that's not exposed through fdinfo there.

>  
>  	if (IS_ERR(queue->profiling.slots)) {
>  		ret = PTR_ERR(queue->profiling.slots);
> @@ -3495,7 +3497,8 @@ int panthor_group_create(struct panthor_file *pfile,
>  						   DRM_PANTHOR_BO_NO_MMAP,
>  						   DRM_PANTHOR_VM_BIND_OP_MAP_NOEXEC |
>  						   DRM_PANTHOR_VM_BIND_OP_MAP_UNCACHED,
> -						   PANTHOR_VM_KERNEL_AUTO_VA);
> +						   PANTHOR_VM_KERNEL_AUTO_VA,
> +						   "Group sync objects");
>  	if (IS_ERR(group->syncobjs)) {
>  		ret = PTR_ERR(group->syncobjs);
>  		goto err_put_group;