Re: [PATCH 2/2] drm/xe: Add a WARN_ON for NULL job in xe_sync_entry_signal

[Nirmoy Das <nirmoy.das@intel.com>]

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Hi Matt,

On 3/18/2024 3:21 PM, Matthew Brost wrote:
> On Mon, Mar 18, 2024 at 02:50:00PM +0100, Nirmoy Das wrote:
>> Add a warn for NULL job when sync->type is
>> DRM_XE_SYNC_TYPE_USER_FENCE. This should be a programming
>> error and should never happen so warn and let the kernel crash
>> if that ever happens.
>>
>> Cc: Matthew Auld<matthew.auld@intel.com>
>> Cc: Matthew Brost<matthew.brost@intel.com>
>> Signed-off-by: Nirmoy Das<nirmoy.das@intel.com>
>> ---
>>   drivers/gpu/drm/xe/xe_sync.c | 1 +
>>   1 file changed, 1 insertion(+)
>>
>> diff --git a/drivers/gpu/drm/xe/xe_sync.c b/drivers/gpu/drm/xe/xe_sync.c
>> index 02c9577fe418..2b45950aa0af 100644
>> --- a/drivers/gpu/drm/xe/xe_sync.c
>> +++ b/drivers/gpu/drm/xe/xe_sync.c
>> @@ -255,6 +255,7 @@ void xe_sync_entry_signal(struct xe_sync_entry *sync, struct xe_sched_job *job,
>>   			dma_fence_put(fence);
>>   		}
>>   	} else if (sync->type == DRM_XE_SYNC_TYPE_USER_FENCE) {
>> +		XE_WARN_ON(job);
> For a warn on you this inverted - a WARN_ON(true) will pop.
Thanks,  that was stupid of me. I meant to do "WARN_ON(!job)"

>
> But I think we should actually use an xe_assert here which has this
> opposite behavior - pops on xe_assert(xe, false).
>
> So the I think it should be:
>
> xe_assert(xe, job);

xe_assert needed a xe device struct which I can't find a better way to 
retrieve than to pass it on as new argument

I think that is bit too much change for it. I will resend with 
WARN_ON(!job).


Regards,

Nirmoy

>
> Matt
>
>>   		job->user_fence.used = true;
>>   		job->user_fence.addr = sync->addr;
>>   		job->user_fence.value = sync->timeline_value;
>> -- 
>> 2.42.0
>>

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