Re: [Intel-gfx] [PATCH 07/15] drm/i915/guc/slpc: Remove BUG_ON in guc_submission_disable

Matthew Brost
2021-07-28T00:20:44Z

On Mon, Jul 26, 2021 at 12:07:52PM -0700, Vinay Belgaumkar wrote:
> The assumption when it was added was there would be no wakerefs
> held. However, if we fail to enable SLPC, we will still be
> holding a wakeref.
>

So this is if intel_guc_slpc_enable() fails, right? Not seeing where the
wakeref is taken. It also seems wrong not to drop the wakeref before
calling intel_guc_submission_disable, hence the GEM_BUG_ON in this
function.

Can you explain this bit more?

Matt

> Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
> ---
> drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 4 ----
> 1 file changed, 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
> index b6338742a594..48cbd800ca54 100644
> --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
> +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
> @@ -2523,10 +2523,6 @@ void intel_guc_submission_enable(struct intel_guc *guc)
>
> void intel_guc_submission_disable(struct intel_guc *guc)
> {
> - struct intel_gt *gt = guc_to_gt(guc);
> -
> - GEM_BUG_ON(gt->awake); /* GT should be parked first */
> -
> /* Note: By the time we're here, GuC may have already been reset */
> }
>
> --
> 2.25.0