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[AMD Official Use Only - Internal Distribution Only]<br>
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yes, adding excl fence again as shared one is more reliable<br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Christian König <ckoenig.leichtzumerken@gmail.com><br>
<b>Sent:</b> Wednesday, March 18, 2020 4:03:14 PM<br>
<b>To:</b> Pan, Xinhui <Xinhui.Pan@amd.com><br>
<b>Cc:</b> amd-gfx@lists.freedesktop.org <amd-gfx@lists.freedesktop.org>; Liu, Monk <Monk.Liu@amd.com><br>
<b>Subject:</b> Re: [PATCH] drm/amdgpu: fix and cleanup amdgpu_gem_object_close v2</font>
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<div class="PlainText">The key point is that 10ms should be sufficient that either the move or
<br>
the update is finished.<br>
<br>
One alternative which came to my mind would be to add the exclusive <br>
fence as shared as well in this case.<br>
<br>
This way we won't need to block at all.<br>
<br>
Christian.<br>
<br>
Am 18.03.20 um 09:00 schrieb Pan, Xinhui:<br>
> I wonder if it really fix anything with such small delay. but it should be no harm anyway.<br>
><br>
> Reviewed-by: xinhui pan <xinhui.pan@amd.com><br>
><br>
>> 2020年3月18日 15:51,Christian König <ckoenig.leichtzumerken@gmail.com> 写道:<br>
>><br>
>> Ping? Xinhui can I get an rb for this?<br>
>><br>
>> Thanks,<br>
>> Christian.<br>
>><br>
>> Am 16.03.20 um 14:22 schrieb Christian König:<br>
>>> The problem is that we can't add the clear fence to the BO<br>
>>> when there is an exclusive fence on it since we can't<br>
>>> guarantee the the clear fence will complete after the<br>
>>> exclusive one.<br>
>>><br>
>>> To fix this refactor the function and wait for any potential<br>
>>> exclusive fence with a small timeout before adding the<br>
>>> shared clear fence.<br>
>>><br>
>>> v2: fix warning<br>
>>><br>
>>> Signed-off-by: Christian König <christian.koenig@amd.com><br>
>>> ---<br>
>>> drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c | 43 +++++++++++++++----------<br>
>>> 1 file changed, 26 insertions(+), 17 deletions(-)<br>
>>><br>
>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c<br>
>>> index 5bec66e6b1f8..49c91dac35a0 100644<br>
>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c<br>
>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c<br>
>>> @@ -161,10 +161,11 @@ void amdgpu_gem_object_close(struct drm_gem_object *obj,<br>
>>> struct amdgpu_bo_list_entry vm_pd;<br>
>>> struct list_head list, duplicates;<br>
>>> + struct dma_fence *fence = NULL;<br>
>>> struct ttm_validate_buffer tv;<br>
>>> struct ww_acquire_ctx ticket;<br>
>>> struct amdgpu_bo_va *bo_va;<br>
>>> - int r;<br>
>>> + long r;<br>
>>> INIT_LIST_HEAD(&list);<br>
>>> INIT_LIST_HEAD(&duplicates);<br>
>>> @@ -178,28 +179,36 @@ void amdgpu_gem_object_close(struct drm_gem_object *obj,<br>
>>> r = ttm_eu_reserve_buffers(&ticket, &list, false, &duplicates);<br>
>>> if (r) {<br>
>>> dev_err(adev->dev, "leaking bo va because "<br>
>>> - "we fail to reserve bo (%d)\n", r);<br>
>>> + "we fail to reserve bo (%ld)\n", r);<br>
>>> return;<br>
>>> }<br>
>>> bo_va = amdgpu_vm_bo_find(vm, bo);<br>
>>> - if (bo_va && --bo_va->ref_count == 0) {<br>
>>> - amdgpu_vm_bo_rmv(adev, bo_va);<br>
>>> + if (!bo_va || --bo_va->ref_count)<br>
>>> + goto out_unlock;<br>
>>> - if (amdgpu_vm_ready(vm)) {<br>
>>> - struct dma_fence *fence = NULL;<br>
>>> + amdgpu_vm_bo_rmv(adev, bo_va);<br>
>>> + if (!amdgpu_vm_ready(vm))<br>
>>> + goto out_unlock;<br>
>>> - r = amdgpu_vm_clear_freed(adev, vm, &fence);<br>
>>> - if (unlikely(r)) {<br>
>>> - dev_err(adev->dev, "failed to clear page "<br>
>>> - "tables on GEM object close (%d)\n", r);<br>
>>> - }<br>
>>> - if (fence) {<br>
>>> - amdgpu_bo_fence(bo, fence, true);<br>
>>> - dma_fence_put(fence);<br>
>>> - }<br>
>>> - }<br>
>>> - }<br>
>>> + r = amdgpu_vm_clear_freed(adev, vm, &fence);<br>
>>> + if (r || !fence)<br>
>>> + goto out_unlock;<br>
>>> +<br>
>>> + r = dma_resv_wait_timeout_rcu(bo->tbo.base.resv, false, false,<br>
>>> + msecs_to_jiffies(10));<br>
>>> + if (r == 0)<br>
>>> + r = -ETIMEDOUT;<br>
>>> + if (r)<br>
>>> + goto out_unlock;<br>
>>> +<br>
>>> + amdgpu_bo_fence(bo, fence, true);<br>
>>> + dma_fence_put(fence);<br>
>>> +<br>
>>> +out_unlock:<br>
>>> + if (unlikely(r < 0))<br>
>>> + dev_err(adev->dev, "failed to clear page "<br>
>>> + "tables on GEM object close (%ld)\n", r);<br>
>>> ttm_eu_backoff_reservation(&ticket, &list);<br>
>>> }<br>
>>> <br>
<br>
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