[Intel-gfx] [PATCH 01/12] drm/i915/guc: Avoid reclaim locks during reset

[Michal Wajdeczko]

On Mon, 01 Jul 2019 12:04:51 +0200, Chris Wilson  
<chris at chris-wilson.co.uk> wrote:

> During reset, we must be very selective in which locks we take as most
> are tainted by being held across a wait or reclaim (kmalloc) which
> implicitly waits. Inside the guc reset path, we reset the ADS to sane
> defaults, but must keep it pinned from initialisation to avoid having to
> pin it during reset.
>
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>

Reviewed-by: Michal Wajdeczko <michal.wajdeczko at intel.com>

but I'm little worried about leaving stale guc->ads_blob below:

> @@ -183,7 +183,7 @@ int intel_guc_ads_create(struct intel_guc *guc)
> void intel_guc_ads_destroy(struct intel_guc *guc)
>  {
> -	i915_vma_unpin_and_release(&guc->ads_vma, 0);
> +	i915_vma_unpin_and_release(&guc->ads_vma, I915_VMA_RELEASE_MAP);
>  }

maybe there is a way to get ptr right from the pinned/mapped vma
without introducing extra separate field that might go out of sync ?

Michal