[PATCH v2] drm/amdgpu: check vm ready by amdgpu_vm->evicting flag

[PATCH v2] drm/amdgpu: check vm ready by amdgpu_vm->evicting flag

[Qiang Yu]

Workstation application ANSA/META v21.1.4 get this error dmesg when
running CI test suite provided by ANSA/META:
[drm:amdgpu_gem_va_ioctl [amdgpu]] *ERROR* Couldn't update BO_VA (-16)

This is caused by:
1. create a 256MB buffer in invisible VRAM
2. CPU map the buffer and access it causes vm_fault and try to move
   it to visible VRAM
3. force visible VRAM space and traverse all VRAM bos to check if
   evicting this bo is valuable
4. when checking a VM bo (in invisible VRAM), amdgpu_vm_evictable()
   will set amdgpu_vm->evicting, but latter due to not in visible
   VRAM, won't really evict it so not add it to amdgpu_vm->evicted
5. before next CS to clear the amdgpu_vm->evicting, user VM ops
   ioctl will pass amdgpu_vm_ready() (check amdgpu_vm->evicted)
   but fail in amdgpu_vm_bo_update_mapping() (check
   amdgpu_vm->evicting) and get this error log

This error won't affect functionality as next CS will finish the
waiting VM ops. But we'd better clear the error log by checking
the amdgpu_vm->evicting flag in amdgpu_vm_ready() to stop calling
amdgpu_vm_bo_update_mapping() latter.

Another reason is amdgpu_vm->evicted list holds all BOs (both
user buffer and page table), but only page table BOs' eviction
prevent VM ops. amdgpu_vm->evicting flag is set only for page
table BOs, so we should use evicting flag instead of evicted list
in amdgpu_vm_ready().

The side effect of This change is: previously blocked VM op (user
buffer in "evicted" list but no page table in it) gets done
immediately.

v2: update commit comments.

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Qiang Yu <qiang.yu@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index 37acd8911168..2cd9f1a2e5fa 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -770,11 +770,16 @@ int amdgpu_vm_validate_pt_bos(struct amdgpu_device *adev, struct amdgpu_vm *vm,
  * Check if all VM PDs/PTs are ready for updates
  *
  * Returns:
- * True if eviction list is empty.
+ * True if VM is not evicting.
  */
 bool amdgpu_vm_ready(struct amdgpu_vm *vm)
 {
-	return list_empty(&vm->evicted);
+	bool ret;
+
+	amdgpu_vm_eviction_lock(vm);
+	ret = !vm->evicting;
+	amdgpu_vm_eviction_unlock(vm);
+	return ret;
 }
 
 /**
-- 
2.25.1

Re: [PATCH v2] drm/amdgpu: check vm ready by amdgpu_vm->evicting flag

[Paul Menzel]

Dear Qiang,


Am 22.02.22 um 03:46 schrieb Qiang Yu:
> Workstation application ANSA/META v21.1.4 get this error dmesg when
> running CI test suite provided by ANSA/META:
> [drm:amdgpu_gem_va_ioctl [amdgpu]] *ERROR* Couldn't update BO_VA (-16)
> 
> This is caused by:
> 1. create a 256MB buffer in invisible VRAM
> 2. CPU map the buffer and access it causes vm_fault and try to move
>     it to visible VRAM
> 3. force visible VRAM space and traverse all VRAM bos to check if
>     evicting this bo is valuable
> 4. when checking a VM bo (in invisible VRAM), amdgpu_vm_evictable()
>     will set amdgpu_vm->evicting, but latter due to not in visible
>     VRAM, won't really evict it so not add it to amdgpu_vm->evicted
> 5. before next CS to clear the amdgpu_vm->evicting, user VM ops
>     ioctl will pass amdgpu_vm_ready() (check amdgpu_vm->evicted)
>     but fail in amdgpu_vm_bo_update_mapping() (check
>     amdgpu_vm->evicting) and get this error log
> 
> This error won't affect functionality as next CS will finish the
> waiting VM ops. But we'd better clear the error log by checking
> the amdgpu_vm->evicting flag in amdgpu_vm_ready() to stop calling
> amdgpu_vm_bo_update_mapping() latter.

later
> Another reason is amdgpu_vm->evicted list holds all BOs (both
> user buffer and page table), but only page table BOs' eviction
> prevent VM ops. amdgpu_vm->evicting flag is set only for page
> table BOs, so we should use evicting flag instead of evicted list
> in amdgpu_vm_ready().
> 
> The side effect of This change is: previously blocked VM op (user

this

> buffer in "evicted" list but no page table in it) gets done
> immediately.
> 
> v2: update commit comments.
> 
> Reviewed-by: Christian König <christian.koenig@amd.com>
> Signed-off-by: Qiang Yu <qiang.yu@amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 9 +++++++--
>   1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> index 37acd8911168..2cd9f1a2e5fa 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> @@ -770,11 +770,16 @@ int amdgpu_vm_validate_pt_bos(struct amdgpu_device *adev, struct amdgpu_vm *vm,
>    * Check if all VM PDs/PTs are ready for updates
>    *
>    * Returns:
> - * True if eviction list is empty.
> + * True if VM is not evicting.
>    */
>   bool amdgpu_vm_ready(struct amdgpu_vm *vm)
>   {
> -	return list_empty(&vm->evicted);
> +	bool ret;
> +
> +	amdgpu_vm_eviction_lock(vm);
> +	ret = !vm->evicting;
> +	amdgpu_vm_eviction_unlock(vm);
> +	return ret;
>   }
>   
>   /**

Acked-by: Paul Menzel <pmenzel@molgen.mpg.de>


Kind regards,

Paul

Re: [PATCH v2] drm/amdgpu: check vm ready by amdgpu_vm->evicting flag

[Qiang Yu]

On Wed, Feb 23, 2022 at 3:47 PM Paul Menzel <pmenzel@molgen.mpg.de> wrote:
>
> Dear Qiang,
>
>
> Am 22.02.22 um 03:46 schrieb Qiang Yu:
> > Workstation application ANSA/META v21.1.4 get this error dmesg when
> > running CI test suite provided by ANSA/META:
> > [drm:amdgpu_gem_va_ioctl [amdgpu]] *ERROR* Couldn't update BO_VA (-16)
> >
> > This is caused by:
> > 1. create a 256MB buffer in invisible VRAM
> > 2. CPU map the buffer and access it causes vm_fault and try to move
> >     it to visible VRAM
> > 3. force visible VRAM space and traverse all VRAM bos to check if
> >     evicting this bo is valuable
> > 4. when checking a VM bo (in invisible VRAM), amdgpu_vm_evictable()
> >     will set amdgpu_vm->evicting, but latter due to not in visible
> >     VRAM, won't really evict it so not add it to amdgpu_vm->evicted
> > 5. before next CS to clear the amdgpu_vm->evicting, user VM ops
> >     ioctl will pass amdgpu_vm_ready() (check amdgpu_vm->evicted)
> >     but fail in amdgpu_vm_bo_update_mapping() (check
> >     amdgpu_vm->evicting) and get this error log
> >
> > This error won't affect functionality as next CS will finish the
> > waiting VM ops. But we'd better clear the error log by checking
> > the amdgpu_vm->evicting flag in amdgpu_vm_ready() to stop calling
> > amdgpu_vm_bo_update_mapping() latter.
>
> later
> > Another reason is amdgpu_vm->evicted list holds all BOs (both
> > user buffer and page table), but only page table BOs' eviction
> > prevent VM ops. amdgpu_vm->evicting flag is set only for page
> > table BOs, so we should use evicting flag instead of evicted list
> > in amdgpu_vm_ready().
> >
> > The side effect of This change is: previously blocked VM op (user
>
> this
>
> > buffer in "evicted" list but no page table in it) gets done
> > immediately.
> >
> > v2: update commit comments.
> >
> > Reviewed-by: Christian König <christian.koenig@amd.com>
> > Signed-off-by: Qiang Yu <qiang.yu@amd.com>
> > ---
> >   drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 9 +++++++--
> >   1 file changed, 7 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> > index 37acd8911168..2cd9f1a2e5fa 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> > @@ -770,11 +770,16 @@ int amdgpu_vm_validate_pt_bos(struct amdgpu_device *adev, struct amdgpu_vm *vm,
> >    * Check if all VM PDs/PTs are ready for updates
> >    *
> >    * Returns:
> > - * True if eviction list is empty.
> > + * True if VM is not evicting.
> >    */
> >   bool amdgpu_vm_ready(struct amdgpu_vm *vm)
> >   {
> > -     return list_empty(&vm->evicted);
> > +     bool ret;
> > +
> > +     amdgpu_vm_eviction_lock(vm);
> > +     ret = !vm->evicting;
> > +     amdgpu_vm_eviction_unlock(vm);
> > +     return ret;
> >   }
> >
> >   /**
>
> Acked-by: Paul Menzel <pmenzel@molgen.mpg.de>
>
Thanks, will submit with the typo fixed.

Regards,
Qiang

>
> Kind regards,
>
> Paul

Re: [PATCH v2] drm/amdgpu: check vm ready by amdgpu_vm->evicting flag

[youling257]

this patch cause suspend to disk resume amdgpu hang,  [drm:amdgpu_job_timedout [amdgpu]] *ERROR* ring gfx timeout, signaled seq=8330, emitted seq=8332

https://gitlab.freedesktop.org/drm/amd/-/issues/1915

Re: [PATCH v2] drm/amdgpu: check vm ready by amdgpu_vm->evicting flag

[youling 257]

https://gitlab.freedesktop.org/drm/amd/-/issues/1922

2022-03-01 1:26 GMT+08:00, youling257 <youling257@gmail.com>:
> this patch cause suspend to disk resume amdgpu hang,
> [drm:amdgpu_job_timedout [amdgpu]] *ERROR* ring gfx timeout, signaled
> seq=8330, emitted seq=8332
>
> https://gitlab.freedesktop.org/drm/amd/-/issues/1915
>