[Intel-gfx] [PATCH] drm/i915: Flush context free work on cleanup

[Tvrtko Ursulin]

On 12/11/2019 09:06, Chris Wilson wrote:
> Throw in a flush_work() and rcu_barrier() to specifically flush the
> context cleanup work.
> 
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=112248
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>

Fixes: a4e7ccdac38e ("drm/i915: Move context management under GEM")

? Might have gotten it wrong.. only did a quick dig.

> ---
>   drivers/gpu/drm/i915/gem/i915_gem_context.c | 1 +
>   drivers/gpu/drm/i915/gt/intel_engine_cs.c   | 1 +
>   2 files changed, 2 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c
> index 72d389afa28a..17f395672e5e 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
> @@ -776,6 +776,7 @@ int i915_gem_init_contexts(struct drm_i915_private *i915)
>   void i915_gem_driver_release__contexts(struct drm_i915_private *i915)
>   {
>   	destroy_kernel_context(&i915->kernel_context);
> +	flush_work(&i915->gem.contexts.free_work);
>   }
>   
>   static int context_idr_cleanup(int id, void *p, void *data)
> diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
> index b9613d044393..1f68700a2311 100644
> --- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
> +++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
> @@ -402,6 +402,7 @@ void intel_engines_cleanup(struct intel_gt *gt)
>   		gt->engine[id] = NULL;
>   		gt->i915->engine[id] = NULL;
>   	}
> +	rcu_barrier();

Why this?

>   }
>   
>   /**
> 

Regards,

Tvrtko