[Intel-gfx] [PATCH] drm/i915/guc: do not capture error state on exiting context

[Ceraolo Spurio, Daniele]

On 9/26/2022 3:44 PM, Andi Shyti wrote:
> Hi Andrzej,
>
> On Mon, Sep 26, 2022 at 11:54:09PM +0200, Andrzej Hajda wrote:
>> Capturing error state is time consuming (up to 350ms on DG2), so it should
>> be avoided if possible. Context reset triggered by context removal is a
>> good example.
>> With this patch multiple igt tests will not timeout and should run faster.
>>
>> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1551
>> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/3952
>> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/5891
>> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/6268
>> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/6281
>> Signed-off-by: Andrzej Hajda <andrzej.hajda at intel.com>
> fine for me:
>
> Reviewed-by: Andi Shyti <andi.shyti at linux.intel.com>
>
> Just to be on the safe side, can we also have the ack from any of
> the GuC folks? Daniele, John?
>
> Andi
>
>
>> ---
>>   drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 3 ++-
>>   1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> 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 22ba66e48a9b01..cb58029208afe1 100644
>> --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
>> +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
>> @@ -4425,7 +4425,8 @@ static void guc_handle_context_reset(struct intel_guc *guc,
>>   	trace_intel_context_reset(ce);
>>   
>>   	if (likely(!intel_context_is_banned(ce))) {
>> -		capture_error_state(guc, ce);
>> +		if (!intel_context_is_exiting(ce))
>> +			capture_error_state(guc, ce);
>>   		guc_context_replay(ce);

You definitely don't want to replay requests of a context that is going 
away.

This seems at least in part due to 
https://patchwork.freedesktop.org/patch/487531/, where we replaced the 
"context_ban" with "context_exiting". There are several places where we 
skipped operations if the context was banned (here included) which are 
now not covered anymore for exiting contexts. Maybe we need a new 
checker function to check both flags in places where we don't care why 
the context is being removed (ban vs exiting), just that it is?

Daniele

>>   	} else {
>>   		drm_info(&guc_to_gt(guc)->i915->drm,
>> -- 
>> 2.34.1