On 7/27/2021 5:20 PM, Matthew Brost wrote:
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?
I should change the desc a little. The BUG_ON assumed GT would not be
awake i.e at shutdown, and there would be 0 GT_PM references. However,
this slpc_enable is in gt_resume path (gt_init_hw calls uc_init_hw).
Here, gt_pm_get reference is held, so it will result in BUG_ON when
submission_disable is called.
Thanks,
Vinay.
Matt
Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@xxxxxxxxx>
---
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
