Re: [PATCH] drm/xe/guc: Handle timing out of signaled jobs gracefully

["Thomas Hellström" <thomas.hellstrom@linux.intel.com>]

Hi,

On Fri, 2024-02-23 at 12:46 -0800, Matthew Brost wrote:
> Timing out of signaled jobs can happen during regular operations
> (e.g.
> an exec queue closed immediately after last fence signaled). The TDR
> can
> pass the worker which free jobs. Rather than running through the TDR
> if
> signaled job is found, simply free it without any debug messages.
> 
> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
> Reported-by: José Roberto de Souza <jose.souza@intel.com>
> Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/1271
> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
> ---
>  drivers/gpu/drm/xe/xe_guc_submit.c | 32 ++++++++++++++++++----------
> --
>  1 file changed, 19 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_guc_submit.c
> b/drivers/gpu/drm/xe/xe_guc_submit.c
> index ff77bc8da1b2..29748e40555f 100644
> --- a/drivers/gpu/drm/xe/xe_guc_submit.c
> +++ b/drivers/gpu/drm/xe/xe_guc_submit.c
> @@ -929,20 +929,26 @@ guc_exec_queue_timedout_job(struct
> drm_sched_job *drm_job)
>  	int err = -ETIME;
>  	int i = 0;
>  
> -	if (!test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &job->fence-
> >flags)) {
> -		drm_notice(&xe->drm, "Timedout job: seqno=%u,
> guc_id=%d, flags=0x%lx",
> -			   xe_sched_job_seqno(job), q->guc->id, q-
> >flags);
> -		xe_gt_WARN(q->gt, q->flags & EXEC_QUEUE_FLAG_KERNEL,
> -			   "Kernel-submitted job timed out\n");
> -		xe_gt_WARN(q->gt, q->flags & EXEC_QUEUE_FLAG_VM &&
> !exec_queue_killed(q),
> -			   "VM job timed out on non-killed
> execqueue\n");
> -
> -		simple_error_capture(q);
> -		xe_devcoredump(job);
> -	} else {
> -		drm_dbg(&xe->drm, "Timedout signaled job: seqno=%u,
> guc_id=%d, flags=0x%lx",
> -			 xe_sched_job_seqno(job), q->guc->id, q-
> >flags);
> +	/*
> +	 * TDR has fired before free job worker. Common if exec
> queue
> +	 * immediately closed after last fence signaled.
> +	 */
> +	if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &job->fence-
> >flags)) {
Perhaps use dma_fence_is_signaled() to double-check?

Either way 
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>

> +		guc_exec_queue_free_job(drm_job);
> +
> +		return DRM_GPU_SCHED_STAT_NOMINAL;
>  	}
> +
> +	drm_notice(&xe->drm, "Timedout job: seqno=%u, guc_id=%d,
> flags=0x%lx",
> +		   xe_sched_job_seqno(job), q->guc->id, q->flags);
> +	xe_gt_WARN(q->gt, q->flags & EXEC_QUEUE_FLAG_KERNEL,
> +		   "Kernel-submitted job timed out\n");
> +	xe_gt_WARN(q->gt, q->flags & EXEC_QUEUE_FLAG_VM &&
> !exec_queue_killed(q),
> +		   "VM job timed out on non-killed execqueue\n");
> +
> +	simple_error_capture(q);
> +	xe_devcoredump(job);
> +
>  	trace_xe_sched_job_timedout(job);
>  
>  	/* Kill the run_job entry point */