Re: [PATCH drm-next v7 02/13] drm: manager to keep track of GPUs VA mappings

From: Donald Robson
Date: Mon Jul 17 2023 - 06:02:27 EST


Hi Danilo,
The below part of the documentation is out of date now.
Thanks,
Donald

On Thu, 2023-07-13 at 19:03 +0200, Danilo Krummrich wrote:
>
> +
> +/**
> + * DOC: Locking
> + *
> + * Generally, the GPU VA manager does not take care of locking itself, it is
> + * the drivers responsibility to take care about locking. Drivers might want to
> + * protect the following operations: inserting, removing and iterating
> + * &drm_gpuva objects as well as generating all kinds of operations, such as
> + * split / merge or prefetch.
> + *
> + * The GPU VA manager also does not take care of the locking of the backing
> + * &drm_gem_object buffers GPU VA lists by itself; drivers are responsible to
> + * enforce mutual exclusion using either the GEMs dma_resv lock or alternatively
> + * a driver specific external lock by setting the @DRM_GPUVA_MANAGER_LOCK_EXTERN
> + * flag.
> + *
> + * For the latter, functions such as drm_gpuva_link() or drm_gpuva_unlink()
> + * contain lockdep checks to indicate locking issues. For this to work drivers
> + * must provide (in case the @DRM_GPUVA_MANAGER_LOCK_EXTERN flag is set) their
> + * external lock with drm_gpuva_manager_set_ext_lock() after initialization.
> + */
>