[PATCH] drm/amdkfd: only allow heavy-weight TLB flush on some ASICs for SVM too

[Felix Kuehling]

Am 2022-04-14 um 04:19 schrieb Lang Yu:
> The idea is from commit a50fe7078035 ("drm/amdkfd: Only apply heavy-weight
> TLB flush on Aldebaran") and commit f61c40c0757a ("drm/amdkfd: enable
> heavy-weight TLB flush on Arcturus"). Otherwise, we will run into problems
> on some ASICs when running SVM applications.
>
> Signed-off-by: Lang Yu <Lang.Yu at amd.com>
> ---
>   drivers/gpu/drm/amd/amdkfd/kfd_chardev.c | 8 --------
>   drivers/gpu/drm/amd/amdkfd/kfd_priv.h    | 8 ++++++++
>   drivers/gpu/drm/amd/amdkfd/kfd_svm.c     | 4 +++-
>   3 files changed, 11 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
> index 91f82a9ccdaf..459f59e3d0ed 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
> @@ -1128,14 +1128,6 @@ static int kfd_ioctl_free_memory_of_gpu(struct file *filep,
>   	return ret;
>   }
>   
> -static bool kfd_flush_tlb_after_unmap(struct kfd_dev *dev)
> -{
> -	return KFD_GC_VERSION(dev) == IP_VERSION(9, 4, 2) ||
> -		(KFD_GC_VERSION(dev) == IP_VERSION(9, 4, 1) &&
> -		dev->adev->sdma.instance[0].fw_version >= 18) ||
> -		KFD_GC_VERSION(dev) == IP_VERSION(9, 4, 0);
> -}
> -
>   static int kfd_ioctl_map_memory_to_gpu(struct file *filep,
>   					struct kfd_process *p, void *data)
>   {
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_priv.h b/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
> index 8a43def1f638..aff6f598ff2c 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
> @@ -1328,6 +1328,14 @@ void kfd_signal_poison_consumed_event(struct kfd_dev *dev, u32 pasid);
>   
>   void kfd_flush_tlb(struct kfd_process_device *pdd, enum TLB_FLUSH_TYPE type);
>   
> +static inline bool kfd_flush_tlb_after_unmap(struct kfd_dev *dev)
> +{
> +	return KFD_GC_VERSION(dev) == IP_VERSION(9, 4, 2) ||
> +	       (KFD_GC_VERSION(dev) == IP_VERSION(9, 4, 1) &&
> +	       dev->adev->sdma.instance[0].fw_version >= 18) ||
> +	       KFD_GC_VERSION(dev) == IP_VERSION(9, 4, 0);
> +}
> +
>   bool kfd_is_locked(void);
>   
>   /* Compute profile */
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> index 459fa07a3bcc..5afe216cf099 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> @@ -1229,7 +1229,9 @@ svm_range_unmap_from_gpus(struct svm_range *prange, unsigned long start,
>   			if (r)
>   				break;
>   		}
> -		kfd_flush_tlb(pdd, TLB_FLUSH_HEAVYWEIGHT);
> +
> +		if (kfd_flush_tlb_after_unmap(pdd->dev))
> +			kfd_flush_tlb(pdd, TLB_FLUSH_HEAVYWEIGHT);

Then you probably need to add another flush_tlb call in 
svm_range_map_to_gpus.

Regards,
   Felix


>   	}
>   
>   	return r;