Am 03.01.2018 um 09:10 schrieb Zhou, David(ChunMing):
>
> On 2018å¹´01æ??02æ?¥ 22:47, Christian König wrote:
>> Try to lock moved BOs if it's successful we can update the
>> PTEs directly to the new location.
>>
>> v2: rebase
>>
>> Signed-off-by: Christian König <christian.koenig at amd.com>
>> ---
>> drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 15 ++++++++++++++-
>> 1 file changed, 14 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
>> index 3632c69f1814..c1c5ccdee783 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
>> @@ -1697,18 +1697,31 @@ int amdgpu_vm_handle_moved(struct amdgpu_device *adev,
>> spin_lock(&vm->status_lock);
>> while (!list_empty(&vm->moved)) {
>> struct amdgpu_bo_va *bo_va;
>> + struct reservation_object *resv;
>>
>> bo_va = list_first_entry(&vm->moved,
>> struct amdgpu_bo_va, base.vm_status);
>> spin_unlock(&vm->status_lock);
>>
>> + resv = bo_va->base.bo->tbo.resv;
>> +
>> /* Per VM BOs never need to bo cleared in the page tables */
> This reminders us Per-VM-BOs need to cleared as well after we allow to
> evict/swap out per-vm-bos.
Actually they don't. The page tables only need to be valid during CS.
So what happens is that the per VM-BOs are validated in right before we
call amdgpu_vm_handle_moved().
Regards,
Christian.
>
> Regards,
> David Zhou
>> - clear = bo_va->base.bo->tbo.resv != vm->root.base.bo->tbo.resv;
>> + if (resv == vm->root.base.bo->tbo.resv)
>> + clear = false;
>> + /* Try to reserve the BO to avoid clearing its ptes */
>> + else if (reservation_object_trylock(resv))
>> + clear = false;
>> + /* Somebody else is using the BO right now */
>> + else
>> + clear = true;
>>
>> r = amdgpu_vm_bo_update(adev, bo_va, clear);
>> if (r)
>> return r;
>>
>> + if (!clear && resv != vm->root.base.bo->tbo.resv)
>> + reservation_object_unlock(resv);
>> +
>> spin_lock(&vm->status_lock);
>> }
>> spin_unlock(&vm->status_lock);
