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

[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?


>
>>
>>
>>>       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))
>>>
>