[Intel-gfx] [PATCH v3 1/7] drm/i915: Avoid using the i915_fence_array when collecting dependencies

[Matthew Auld]

On 17/12/2021 14:52, Thomas Hellström wrote:
> Since the gt migration code was using only a single fence for
> dependencies, these were collected in a dma_fence_array. However, it
> turns out that it's illegal to use some dma_fences in a dma_fence_array,
> in particular other dma_fence_arrays and dma_fence_chains, and this
> causes trouble for us moving forward.
> 
> Have the gt migration code instead take a const struct i915_deps for
> dependencies. This means we can skip the dma_fence_array creation
> and instead pass the struct i915_deps instead to circumvent the
> problem.
> 
> v2:
> - Make the prev_deps() function static. (kernel test robot <lkp at intel.com>)
> - Update the struct i915_deps kerneldoc.
> 
> Fixes: 5652df829b3c ("drm/i915/ttm: Update i915_gem_obj_copy_ttm() to be asynchronous")
> Signed-off-by: Thomas Hellström <thomas.hellstrom at linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld at intel.com>