Re: [PATCH v2 2/2] drm/msm: Hangcheck progress detection

From: Dmitry Baryshkov
Date: Wed Nov 02 2022 - 19:35:12 EST


On 02/11/2022 01:33, Rob Clark wrote:
From: Rob Clark <robdclark@xxxxxxxxxxxx>

If the hangcheck timer expires, check if the fw's position in the
cmdstream has advanced (changed) since last timer expiration, and
allow it up to three additional "extensions" to it's alotted time.
The intention is to continue to catch "shader stuck in a loop" type
hangs quickly, but allow more time for things that are actually
making forward progress.

Just out of curiosity: wouldn't position also change for a 'shader stuck in a loop'?


Because we need to sample the CP state twice to detect if there has
not been progress, this also cuts the the timer's duration in half.

v2: Fix typo (REG_A6XX_CP_CSQ_IB2_STAT), add comment

Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
Reviewed-by: Akhil P Oommen <quic_akhilpo@xxxxxxxxxxx>



--
With best wishes
Dmitry