[Intel-gfx] [PATCH] drm/i915/guc: Restore preempt-context across S3/S4

[Michał Winiarski]

On Wed, Sep 19, 2018 at 09:54:32PM +0100, Chris Wilson wrote:
> Stolen memory is lost across S4 (hibernate) or S3-RST as it is a portion
> of ordinary volatile RAM. As we allocate our rings from stolen, this may
> include the rings used for our preempt context and their breadcrumb
> instructions. In order to allow preemption following hibernation and
> loss of stolen memory, we therefore need to repopulate the instructions
> inside the lost ring upon resume. To handle both module load and resume,
> we simply defer constructing the ring to first use.
> 
> Testcase: igt/drv_selftest/live_gem
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Michał Winiarski <michal.winiarski at intel.com>
> Cc: Michal Wajdeczko <michal.wajdeczko at intel.com>

Reviewed-by: Michał Winiarski <michal.winiarski at intel.com>

-Michał

> ---
>  drivers/gpu/drm/i915/intel_guc_submission.c | 80 +++++++--------------
>  1 file changed, 27 insertions(+), 53 deletions(-)