[PATCH v3 2/2] drm/admgpu: Present amdgpu_task_info in VM_FAULTS.

[Christian König]

Am 09.07.2018 um 09:48 schrieb Zhang, Jerry (Junwei):
> On 07/09/2018 03:04 PM, Christian König wrote:
>> Am 09.07.2018 um 07:13 schrieb Zhang, Jerry (Junwei):
>>> On 07/06/2018 03:27 AM, Andrey Grodzovsky wrote:
>>>> Extract and present the reposnsible process and thread when
>>>> VM_FAULT happens.
>>>>
>>>> v2: Use getter and setter functions.
>>>>
>>>> Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky at amd.com>
>>>> ---
>>>>   drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c |  4 ++++
>>>>   drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c  | 10 +++++++---
>>>>   drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c  |  9 +++++++--
>>>>   3 files changed, 18 insertions(+), 5 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c 
>>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
>>>> index 7a625f3..609c8f5 100644
>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
>>>> @@ -187,6 +187,10 @@ static int amdgpu_cs_parser_init(struct 
>>>> amdgpu_cs_parser *p, void *data)
>>>>       if (p->uf_entry.robj)
>>>>           p->job->uf_addr = uf_offset;
>>>>       kfree(chunk_array);
>>>> +
>>>> +    /* Use this opportunity to fill in task info for the vm */
>>>> +    amdgpu_vm_set_task_info(vm);
>>>> +
>>>
>>> Shall we set the task info when vm init?
>>
>> No, vm_init() is called from a completely different process which is 
>> later on user of the VM.
>
> Originally I thought UMD opened DRI node and create a VM by vm_init(), 
> then every command submission
> would be passed in the same VM initialized by vm_init().
>
> So that's different process?

The display server, e.g. X or Wayland.

See with DRI3 the process of opening a connection to the hardware is 
that the display server open the file descriptor and with that calls 
vm_init.

And then this file descriptor is passed to the client processes through IPC.

Regards,
Christian.

>
>
>>
>>>
>>>
>>>>       return 0;
>>>>
>>>>   free_all_kdata:
>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c 
>>>> b/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c
>>>> index 08753e7..75f3ffb 100644
>>>> --- a/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c
>>>> +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c
>>>> @@ -46,7 +46,6 @@
>>>>
>>>>   #include "ivsrcid/ivsrcid_vislands30.h"
>>>>
>>>> -
>>>>   static void gmc_v8_0_set_gmc_funcs(struct amdgpu_device *adev);
>>>>   static void gmc_v8_0_set_irq_funcs(struct amdgpu_device *adev);
>>>>   static int gmc_v8_0_wait_for_idle(void *handle);
>>>> @@ -1449,8 +1448,13 @@ static int gmc_v8_0_process_interrupt(struct 
>>>> amdgpu_device *adev,
>>>>           gmc_v8_0_set_fault_enable_default(adev, false);
>>>>
>>>>       if (printk_ratelimit()) {
>>>> -        dev_err(adev->dev, "GPU fault detected: %d 0x%08x\n",
>>>> -            entry->src_id, entry->src_data[0]);
>>>> +        struct amdgpu_task_info task_info = { 0 };
>>>> +
>>>> +        amdgpu_vm_get_task_info(adev, entry->pasid, &task_info);
>>>
>>> Shall we find vm and get the vm->task_info directly instead of 
>>> filling local variable task_info?
>>> (current style is also OK for me, just for more info)
>>
>> No, we can't guarantee that the task_info pointer in the VM won't be 
>> freed after dropping the spinlock. So returning a copy here is the 
>> better approach.
>>
>>>
>>> And we may also check the return value for "NULL" case, otherwise it 
>>> may cause access errorin dev_err(),
>>> if failed to find vm (although, it's most unlikely to happen).
>>
>> Since we use a copy of the task info we should never get a NULL 
>> pointer. The string should already be zero terminated with the "{ 0 
>> }" initialization above.
>
> Thanks to explain that more.
> Got it, fine for me.
>
> Jerry
>
>>
>> Christian.
>>
>>>
>>> Jerry
>>>
>>>> +
>>>> +        dev_err(adev->dev, "GPU fault detected: %d 0x%08x for 
>>>> process %s pid %d thread %s pid %d\n",
>>>> +            entry->src_id, entry->src_data[0], 
>>>> task_info.process_name,
>>>> +            task_info.tgid, task_info.task_name, task_info.pid);
>>>>           dev_err(adev->dev, " VM_CONTEXT1_PROTECTION_FAULT_ADDR 
>>>> 0x%08X\n",
>>>>               addr);
>>>>           dev_err(adev->dev, " VM_CONTEXT1_PROTECTION_FAULT_STATUS 
>>>> 0x%08X\n",
>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c 
>>>> b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
>>>> index 691a659..9df94b4 100644
>>>> --- a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
>>>> +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
>>>> @@ -259,11 +259,16 @@ static int gmc_v9_0_process_interrupt(struct 
>>>> amdgpu_device *adev,
>>>>       }
>>>>
>>>>       if (printk_ratelimit()) {
>>>> +        struct amdgpu_task_info task_info = { 0 };
>>>> +
>>>> +        amdgpu_vm_get_task_info(adev, entry->pasid, &task_info);
>>>> +
>>>>           dev_err(adev->dev,
>>>> -            "[%s] VMC page fault (src_id:%u ring:%u vmid:%u 
>>>> pasid:%u)\n",
>>>> +            "[%s] VMC page fault (src_id:%u ring:%u vmid:%u 
>>>> pasid:%u, for process %s pid %d thread %s pid %d\n)\n",
>>>>               entry->vmid_src ? "mmhub" : "gfxhub",
>>>>               entry->src_id, entry->ring_id, entry->vmid,
>>>> -            entry->pasid);
>>>> +            entry->pasid, task_info.process_name, task_info.tgid,
>>>> +            task_info.task_name, task_info.pid);
>>>>           dev_err(adev->dev, "  at page 0x%016llx from %d\n",
>>>>               addr, entry->client_id);
>>>>           if (!amdgpu_sriov_vf(adev))
>>>>
>>