Re: [PATCH] drm/xe: Convert kernel job timeout from assert to warning

[Matthew Brost <matthew.brost@intel.com>]

On Tue, Jan 30, 2024 at 10:04:53AM -0800, Matt Roper wrote:
> xe_assert() is intended to be used only for "impossible" situations that
> should never be hit (and if they are hit it means there's a driver bug
> somewhere); assertions are only compiled into debug builds.
> 
> Although we expect jobs submitted by the kernel to be well-behaved and
> run without error, timeouts are a legitimate possibility for reasons
> beyond our control (bad firmware, flaky hardware, etc.).  We should use
> a real WARN if we encounter these, even for non-debug builds, to ensure
> the issue is being properly highlighted in bug reports and such.
> 
> Also give the WARN a more human-readable message and move it below the
> general notice-level message that gets printed for any kind of timeout
> to make the errors a bit more understandable.
> 
> Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
> ---
>  drivers/gpu/drm/xe/xe_guc_submit.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_guc_submit.c b/drivers/gpu/drm/xe/xe_guc_submit.c
> index 2b008ec1b6de..4efc9601e050 100644
> --- a/drivers/gpu/drm/xe/xe_guc_submit.c
> +++ b/drivers/gpu/drm/xe/xe_guc_submit.c
> @@ -23,6 +23,7 @@
>  #include "xe_force_wake.h"
>  #include "xe_gpu_scheduler.h"
>  #include "xe_gt.h"
> +#include "xe_gt_printk.h"
>  #include "xe_guc.h"
>  #include "xe_guc_ct.h"
>  #include "xe_guc_exec_queue_types.h"
> @@ -928,11 +929,12 @@ guc_exec_queue_timedout_job(struct drm_sched_job *drm_job)
>  	int i = 0;
>  
>  	if (!test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &job->fence->flags)) {
> -		xe_assert(xe, !(q->flags & EXEC_QUEUE_FLAG_KERNEL));
>  		xe_assert(xe, !(q->flags & EXEC_QUEUE_FLAG_VM && !exec_queue_killed(q)));

The above condition should also be converted to warn, I had a patch for
this too [1] but prefer yours. Want to post a follow up with this
converted to a warn too?

With that:
Reviewed-by: Matthew Brost <matthew.brost@intel.com>

[1] https://patchwork.freedesktop.org/series/128408/

>  
>  		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");
>  		simple_error_capture(q);
>  		xe_devcoredump(job);
>  	} else {
> -- 
> 2.43.0
>