[PATCH 5/5] drm/amdgpu: drop client_id from VM

[Christian König]

The problem is PASID would never work correctly, it is only 16bits and 
so gets reused quite often.

But we introduced the client_id because we needed an unique 64bit 
identifier which never repeats.

Felix probably didn't knew that when he added the comment.

Regards,
Christian.

Am 21.12.2017 um 04:05 schrieb Chunming Zhou:
> I agree using fence_context is same efficiency with original client 
> id, since vm only has one sdma entity.
>
> But PASID seems be more proper with per-VM-per-process concept, the 
> comment also said that.
>
> Regards,
> David Zhou
> On 2017年12月20日 21:21, Christian König wrote:
>> Use the fence context from the scheduler entity.
>>
>> Signed-off-by: Christian König <christian.koenig at amd.com>
>> ---
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c | 8 ++++----
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c  | 2 --
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h  | 4 ----
>>   3 files changed, 4 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c 
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
>> index d24884b419cb..16884a0b677b 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
>> @@ -115,7 +115,7 @@ static int 
>> amdgpu_vmid_grab_reserved_locked(struct amdgpu_vm *vm,
>>         flushed  = id->flushed_updates;
>>       if ((amdgpu_vmid_had_gpu_reset(adev, id)) ||
>> -        (atomic64_read(&id->owner) != vm->client_id) ||
>> +        (atomic64_read(&id->owner) != vm->entity.fence_context) ||
>>           (job->vm_pd_addr != id->pd_gpu_addr) ||
>>           (updates && (!flushed || updates->context != 
>> flushed->context ||
>>               dma_fence_is_later(updates, flushed))) ||
>> @@ -144,7 +144,7 @@ static int 
>> amdgpu_vmid_grab_reserved_locked(struct amdgpu_vm *vm,
>>           id->flushed_updates = dma_fence_get(updates);
>>       }
>>       id->pd_gpu_addr = job->vm_pd_addr;
>> -    atomic64_set(&id->owner, vm->client_id);
>> +    atomic64_set(&id->owner, vm->entity.fence_context);
>>       job->vm_needs_flush = needs_flush;
>>       if (needs_flush) {
>>           dma_fence_put(id->last_flush);
>> @@ -242,7 +242,7 @@ int amdgpu_vmid_grab(struct amdgpu_vm *vm, struct 
>> amdgpu_ring *ring,
>>           if (amdgpu_vmid_had_gpu_reset(adev, id))
>>               continue;
>>   -        if (atomic64_read(&id->owner) != vm->client_id)
>> +        if (atomic64_read(&id->owner) != vm->entity.fence_context)
>>               continue;
>>             if (job->vm_pd_addr != id->pd_gpu_addr)
>> @@ -291,7 +291,7 @@ int amdgpu_vmid_grab(struct amdgpu_vm *vm, struct 
>> amdgpu_ring *ring,
>>       id->pd_gpu_addr = job->vm_pd_addr;
>>       dma_fence_put(id->flushed_updates);
>>       id->flushed_updates = dma_fence_get(updates);
>> -    atomic64_set(&id->owner, vm->client_id);
>> +    atomic64_set(&id->owner, vm->entity.fence_context);
>>     needs_flush:
>>       job->vm_needs_flush = true;
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c 
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
>> index 946bc21c6d7d..af7dceb7131e 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
>> @@ -2256,7 +2256,6 @@ int amdgpu_vm_init(struct amdgpu_device *adev, 
>> struct amdgpu_vm *vm,
>>       uint64_t init_pde_value = 0;
>>         vm->va = RB_ROOT_CACHED;
>> -    vm->client_id = 
>> atomic64_inc_return(&adev->vm_manager.client_counter);
>>       for (i = 0; i < AMDGPU_MAX_VMHUBS; i++)
>>           vm->reserved_vmid[i] = NULL;
>>       spin_lock_init(&vm->status_lock);
>> @@ -2502,7 +2501,6 @@ void amdgpu_vm_manager_init(struct 
>> amdgpu_device *adev)
>>           adev->vm_manager.seqno[i] = 0;
>>         atomic_set(&adev->vm_manager.vm_pte_next_ring, 0);
>> -    atomic64_set(&adev->vm_manager.client_counter, 0);
>>       spin_lock_init(&adev->vm_manager.prt_lock);
>>       atomic_set(&adev->vm_manager.num_prt_users, 0);
>>   diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h 
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
>> index 78296d1a5b2f..21a80f1bb2b9 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
>> @@ -191,8 +191,6 @@ struct amdgpu_vm {
>>       /* Scheduler entity for page table updates */
>>       struct drm_sched_entity    entity;
>>   -    /* client id and PASID (TODO: replace client_id with PASID) */
>> -    u64                     client_id;
>>       unsigned int        pasid;
>>       /* dedicated to vm */
>>       struct amdgpu_vmid    *reserved_vmid[AMDGPU_MAX_VMHUBS];
>> @@ -230,8 +228,6 @@ struct amdgpu_vm_manager {
>>       struct amdgpu_ring *vm_pte_rings[AMDGPU_MAX_RINGS];
>>       unsigned                vm_pte_num_rings;
>>       atomic_t                vm_pte_next_ring;
>> -    /* client id counter */
>> -    atomic64_t                client_counter;
>>         /* partial resident texture handling */
>>       spinlock_t                prt_lock;
>