Re: [PATCH v2 27/29] drm/xe: Add modparam for SVM notifier size

["Thomas Hellström" <thomas.hellstrom@linux.intel.com>]

On Tue, 2024-10-15 at 20:25 -0700, Matthew Brost wrote:
> Useful to experiment with notifier size and how it affects
> performance.
> 
> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
> ---
>  drivers/gpu/drm/xe/xe_module.h | 1 +
>  drivers/gpu/drm/xe/xe_svm.c    | 5 +++--
>  2 files changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_module.h
> b/drivers/gpu/drm/xe/xe_module.h
> index 161a5e6f717f..5a3bfea8b7b4 100644
> --- a/drivers/gpu/drm/xe/xe_module.h
> +++ b/drivers/gpu/drm/xe/xe_module.h
> @@ -22,6 +22,7 @@ struct xe_modparam {
>  	unsigned int max_vfs;
>  #endif
>  	int wedged_mode;
> +	u32 svm_notifier_size;

Hmm. Shouldn't this be assigned and documented somewhere?

Thanks,
Thomas



>  };
>  
>  extern struct xe_modparam xe_modparam;
> diff --git a/drivers/gpu/drm/xe/xe_svm.c
> b/drivers/gpu/drm/xe/xe_svm.c
> index acf2a3750f38..16e34aaead79 100644
> --- a/drivers/gpu/drm/xe/xe_svm.c
> +++ b/drivers/gpu/drm/xe/xe_svm.c
> @@ -8,6 +8,7 @@
>  #include "xe_bo.h"
>  #include "xe_gt_tlb_invalidation.h"
>  #include "xe_migrate.h"
> +#include "xe_module.h"
>  #include "xe_pt.h"
>  #include "xe_svm.h"
>  #include "xe_ttm_vram_mgr.h"
> @@ -573,8 +574,8 @@ int xe_svm_init(struct xe_vm *vm)
>  
>  	return drm_gpusvm_init(&vm->svm.gpusvm, "Xe SVM", &vm->xe-
> >drm,
>  			       current->mm, xe_svm_devm_owner(vm-
> >xe), 0,
> -			       vm->size, SZ_512M, &gpusvm_ops,
> -			       fault_chunk_sizes,
> +			       vm->size,
> xe_modparam.svm_notifier_size * SZ_1M,
> +			       &gpusvm_ops, fault_chunk_sizes,
>  			       ARRAY_SIZE(fault_chunk_sizes));
>  }
>