[PATCH 1/4] drm/amdgpu: add sched sync for amdgpu job

[zhoucm1]

On 2017年05月10日 16:26, Christian König wrote:
> Am 10.05.2017 um 09:31 schrieb Chunming Zhou:
>> this is an improvement for previous patch, the sched_sync is to store 
>> fence
>> that could be skipped as scheduled, when job is executed, we didn't need
>> pipeline_sync if all fences in sched_sync are signalled, otherwise 
>> insert
>> pipeline_sync still.
>>
>> Change-Id: I26d3a2794272ba94b25753d4bf367326d12f6939
>> Signed-off-by: Chunming Zhou <David1.Zhou at amd.com>
>> ---
>>   drivers/gpu/drm/amd/amdgpu/amdgpu.h     | 1 +
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c  | 7 ++++++-
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_job.c | 5 ++++-
>>   3 files changed, 11 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h 
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
>> index 787acd7..ef018bf 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
>> @@ -1162,6 +1162,7 @@ struct amdgpu_job {
>>       struct amdgpu_vm    *vm;
>>       struct amdgpu_ring    *ring;
>>       struct amdgpu_sync    sync;
>> +    struct amdgpu_sync    sched_sync;
>>       struct amdgpu_ib    *ibs;
>>       struct fence        *fence; /* the hw fence */
>>       uint32_t        preamble_status;
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c 
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c
>> index 2c6624d..86ad507 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c
>> @@ -121,6 +121,7 @@ int amdgpu_ib_schedule(struct amdgpu_ring *ring, 
>> unsigned num_ibs,
>>   {
>>       struct amdgpu_device *adev = ring->adev;
>>       struct amdgpu_ib *ib = &ibs[0];
>> +    struct fence *tmp;
>>       bool skip_preamble, need_ctx_switch;
>>       unsigned patch_offset = ~0;
>>       struct amdgpu_vm *vm;
>> @@ -167,8 +168,12 @@ int amdgpu_ib_schedule(struct amdgpu_ring *ring, 
>> unsigned num_ibs,
>>           return r;
>>       }
>>   -    if (ring->funcs->emit_pipeline_sync && job && 
>> job->need_pipeline_sync)
>> +    if (ring->funcs->emit_pipeline_sync && job &&
>> +        (tmp = amdgpu_sync_get_fence(&job->sched_sync))) {
>> +        job->need_pipeline_sync = true;
>>           amdgpu_ring_emit_pipeline_sync(ring);
>> +        fence_put(tmp);
>> +    }
>>       if (vm) {
>>           amdgpu_ring_insert_nop(ring, extra_nop); /* prevent CE go 
>> too fast than DE */
>>   diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c 
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
>> index cfa97ab..fa0c8b1 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
>> @@ -60,6 +60,7 @@ int amdgpu_job_alloc(struct amdgpu_device *adev, 
>> unsigned num_ibs,
>>       (*job)->need_pipeline_sync = false;
>>         amdgpu_sync_create(&(*job)->sync);
>> +    amdgpu_sync_create(&(*job)->sched_sync);
>>         return 0;
>>   }
>> @@ -98,6 +99,7 @@ static void amdgpu_job_free_cb(struct amd_sched_job 
>> *s_job)
>>         fence_put(job->fence);
>>       amdgpu_sync_free(&job->sync);
>> +    amdgpu_sync_free(&job->sched_sync);
>>       kfree(job);
>>   }
>>   @@ -107,6 +109,7 @@ void amdgpu_job_free(struct amdgpu_job *job)
>>         fence_put(job->fence);
>>       amdgpu_sync_free(&job->sync);
>> +    amdgpu_sync_free(&job->sched_sync);
>>       kfree(job);
>>   }
>>   @@ -154,7 +157,7 @@ static struct fence 
>> *amdgpu_job_dependency(struct amd_sched_job *sched_job)
>>       }
>>         if (amd_sched_dependency_optimized(fence, sched_job->s_entity))
>> -        job->need_pipeline_sync = true;
>> +        amdgpu_sync_fence(job->adev, &job->sched_sync, fence);
>
> This can result in an -ENOMEM 
will handle it.
> and additional to that we only need to remember the last fence 
> optimized like this, not all of them.
>
> So just keep the last one found here in job->sched_fence instead.
I guess this isn't enough.
The dependency is not in order when calling, so the last one is not 
always the last scheduled fence.
And they could be sched fence not hw fence, although they are handled by 
same hw ring, but the sched fence context isn't same.
so we still need sched_sync here, right?

Regards,
David zhou
>
> Regards,
> Christian.
>
>>         return fence;
>>   }
>
>