Re: [PATCH v2 2/2] drm/xe: Invalidate media_gt TLBs in PT code

[Christian König <christian.koenig@xxxxxxx>]

Am 26.08.24 um 19:01 schrieb Matthew Brost:
> Testing on LNL has shown media GT's TLBs need to be invalidated via the
> GuC, update PT code appropriately.
>
> v2:
>   - Do dma_fence_get before first call of invalidation_fence_init (Himal)
>   - No need to check for valid chain fence (Himal)
> v3:
>   - Use dma-fence-array
>
> Fixes: 3330361543fc ("drm/xe/lnl: Add LNL platform definition")
> Signed-off-by: Matthew Brost <matthew.brost@xxxxxxxxx>

Acked-by: Christian König <christian.koenig@xxxxxxx>

> ---
>   drivers/gpu/drm/xe/xe_pt.c | 117 ++++++++++++++++++++++++++++++-------
>   1 file changed, 96 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/gpu/drm/xe/xe_pt.c b/drivers/gpu/drm/xe/xe_pt.c
> index 579ed31b46db..d6353e8969f0 100644
> --- a/drivers/gpu/drm/xe/xe_pt.c
> +++ b/drivers/gpu/drm/xe/xe_pt.c
> @@ -3,6 +3,8 @@
>    * Copyright © 2022 Intel Corporation
>    */
>   
> +#include <linux/dma-fence-array.h>
> +
>   #include "xe_pt.h"
>   
>   #include "regs/xe_gtt_defs.h"
> @@ -1627,9 +1629,11 @@ xe_pt_update_ops_rfence_interval(struct xe_vm_pgtable_update_ops *pt_update_ops,
>   
>   static int vma_reserve_fences(struct xe_device *xe, struct xe_vma *vma)
>   {
> +	int shift = xe_device_get_root_tile(xe)->media_gt ? 1 : 0;
> +
>   	if (!xe_vma_has_no_bo(vma) && !xe_vma_bo(vma)->vm)
>   		return dma_resv_reserve_fences(xe_vma_bo(vma)->ttm.base.resv,
> -					       xe->info.tile_count);
> +					       xe->info.tile_count << shift);
>   
>   	return 0;
>   }
> @@ -1816,6 +1820,7 @@ int xe_pt_update_ops_prepare(struct xe_tile *tile, struct xe_vma_ops *vops)
>   	struct xe_vm_pgtable_update_ops *pt_update_ops =
>   		&vops->pt_update_ops[tile->id];
>   	struct xe_vma_op *op;
> +	int shift = tile->media_gt ? 1 : 0;
>   	int err;
>   
>   	lockdep_assert_held(&vops->vm->lock);
> @@ -1824,7 +1829,7 @@ int xe_pt_update_ops_prepare(struct xe_tile *tile, struct xe_vma_ops *vops)
>   	xe_pt_update_ops_init(pt_update_ops);
>   
>   	err = dma_resv_reserve_fences(xe_vm_resv(vops->vm),
> -				      tile_to_xe(tile)->info.tile_count);
> +				      tile_to_xe(tile)->info.tile_count << shift);
>   	if (err)
>   		return err;
>   
> @@ -1849,13 +1854,20 @@ int xe_pt_update_ops_prepare(struct xe_tile *tile, struct xe_vma_ops *vops)
>   
>   static void bind_op_commit(struct xe_vm *vm, struct xe_tile *tile,
>   			   struct xe_vm_pgtable_update_ops *pt_update_ops,
> -			   struct xe_vma *vma, struct dma_fence *fence)
> +			   struct xe_vma *vma, struct dma_fence *fence,
> +			   struct dma_fence *fence2)
>   {
> -	if (!xe_vma_has_no_bo(vma) && !xe_vma_bo(vma)->vm)
> +	if (!xe_vma_has_no_bo(vma) && !xe_vma_bo(vma)->vm) {
>   		dma_resv_add_fence(xe_vma_bo(vma)->ttm.base.resv, fence,
>   				   pt_update_ops->wait_vm_bookkeep ?
>   				   DMA_RESV_USAGE_KERNEL :
>   				   DMA_RESV_USAGE_BOOKKEEP);
> +		if (fence2)
> +			dma_resv_add_fence(xe_vma_bo(vma)->ttm.base.resv, fence2,
> +					   pt_update_ops->wait_vm_bookkeep ?
> +					   DMA_RESV_USAGE_KERNEL :
> +					   DMA_RESV_USAGE_BOOKKEEP);
> +	}
>   	vma->tile_present |= BIT(tile->id);
>   	vma->tile_staged &= ~BIT(tile->id);
>   	if (xe_vma_is_userptr(vma)) {
> @@ -1875,13 +1887,20 @@ static void bind_op_commit(struct xe_vm *vm, struct xe_tile *tile,
>   
>   static void unbind_op_commit(struct xe_vm *vm, struct xe_tile *tile,
>   			     struct xe_vm_pgtable_update_ops *pt_update_ops,
> -			     struct xe_vma *vma, struct dma_fence *fence)
> +			     struct xe_vma *vma, struct dma_fence *fence,
> +			     struct dma_fence *fence2)
>   {
> -	if (!xe_vma_has_no_bo(vma) && !xe_vma_bo(vma)->vm)
> +	if (!xe_vma_has_no_bo(vma) && !xe_vma_bo(vma)->vm) {
>   		dma_resv_add_fence(xe_vma_bo(vma)->ttm.base.resv, fence,
>   				   pt_update_ops->wait_vm_bookkeep ?
>   				   DMA_RESV_USAGE_KERNEL :
>   				   DMA_RESV_USAGE_BOOKKEEP);
> +		if (fence2)
> +			dma_resv_add_fence(xe_vma_bo(vma)->ttm.base.resv, fence2,
> +					   pt_update_ops->wait_vm_bookkeep ?
> +					   DMA_RESV_USAGE_KERNEL :
> +					   DMA_RESV_USAGE_BOOKKEEP);
> +	}
>   	vma->tile_present &= ~BIT(tile->id);
>   	if (!vma->tile_present) {
>   		list_del_init(&vma->combined_links.rebind);
> @@ -1898,7 +1917,8 @@ static void unbind_op_commit(struct xe_vm *vm, struct xe_tile *tile,
>   static void op_commit(struct xe_vm *vm,
>   		      struct xe_tile *tile,
>   		      struct xe_vm_pgtable_update_ops *pt_update_ops,
> -		      struct xe_vma_op *op, struct dma_fence *fence)
> +		      struct xe_vma_op *op, struct dma_fence *fence,
> +		      struct dma_fence *fence2)
>   {
>   	xe_vm_assert_held(vm);
>   
> @@ -1907,26 +1927,28 @@ static void op_commit(struct xe_vm *vm,
>   		if (!op->map.immediate && xe_vm_in_fault_mode(vm))
>   			break;
>   
> -		bind_op_commit(vm, tile, pt_update_ops, op->map.vma, fence);
> +		bind_op_commit(vm, tile, pt_update_ops, op->map.vma, fence,
> +			       fence2);
>   		break;
>   	case DRM_GPUVA_OP_REMAP:
>   		unbind_op_commit(vm, tile, pt_update_ops,
> -				 gpuva_to_vma(op->base.remap.unmap->va), fence);
> +				 gpuva_to_vma(op->base.remap.unmap->va), fence,
> +				 fence2);
>   
>   		if (op->remap.prev)
>   			bind_op_commit(vm, tile, pt_update_ops, op->remap.prev,
> -				       fence);
> +				       fence, fence2);
>   		if (op->remap.next)
>   			bind_op_commit(vm, tile, pt_update_ops, op->remap.next,
> -				       fence);
> +				       fence, fence2);
>   		break;
>   	case DRM_GPUVA_OP_UNMAP:
>   		unbind_op_commit(vm, tile, pt_update_ops,
> -				 gpuva_to_vma(op->base.unmap.va), fence);
> +				 gpuva_to_vma(op->base.unmap.va), fence, fence2);
>   		break;
>   	case DRM_GPUVA_OP_PREFETCH:
>   		bind_op_commit(vm, tile, pt_update_ops,
> -			       gpuva_to_vma(op->base.prefetch.va), fence);
> +			       gpuva_to_vma(op->base.prefetch.va), fence, fence2);
>   		break;
>   	default:
>   		drm_warn(&vm->xe->drm, "NOT POSSIBLE");
> @@ -1963,7 +1985,9 @@ xe_pt_update_ops_run(struct xe_tile *tile, struct xe_vma_ops *vops)
>   	struct xe_vm_pgtable_update_ops *pt_update_ops =
>   		&vops->pt_update_ops[tile->id];
>   	struct dma_fence *fence;
> -	struct invalidation_fence *ifence = NULL;
> +	struct invalidation_fence *ifence = NULL, *mfence = NULL;
> +	struct dma_fence **fences = NULL;
> +	struct dma_fence_array *cf = NULL;
>   	struct xe_range_fence *rfence;
>   	struct xe_vma_op *op;
>   	int err = 0, i;
> @@ -1996,6 +2020,23 @@ xe_pt_update_ops_run(struct xe_tile *tile, struct xe_vma_ops *vops)
>   			err = -ENOMEM;
>   			goto kill_vm_tile1;
>   		}
> +		if (tile->media_gt) {
> +			mfence = kzalloc(sizeof(*ifence), GFP_KERNEL);
> +			if (!mfence) {
> +				err = -ENOMEM;
> +				goto free_ifence;
> +			}
> +			fences = kmalloc_array(2, sizeof(*fences), GFP_KERNEL);
> +			if (!fences) {
> +				err = -ENOMEM;
> +				goto free_ifence;
> +			}
> +			cf = dma_fence_array_alloc(2);
> +			if (!cf) {
> +				err = -ENOMEM;
> +				goto free_ifence;
> +			}
> +		}
>   	}
>   
>   	rfence = kzalloc(sizeof(*rfence), GFP_KERNEL);
> @@ -2027,19 +2068,50 @@ xe_pt_update_ops_run(struct xe_tile *tile, struct xe_vma_ops *vops)
>   
>   	/* tlb invalidation must be done before signaling rebind */
>   	if (ifence) {
> +		if (mfence)
> +			dma_fence_get(fence);
>   		invalidation_fence_init(tile->primary_gt, ifence, fence,
>   					pt_update_ops->start,
>   					pt_update_ops->last, vm->usm.asid);
> -		fence = &ifence->base.base;
> +		if (mfence) {
> +			invalidation_fence_init(tile->media_gt, mfence, fence,
> +						pt_update_ops->start,
> +						pt_update_ops->last, vm->usm.asid);
> +			fences[0] = &ifence->base.base;
> +			fences[1] = &mfence->base.base;
> +			dma_fence_array_init(cf, 2, fences,
> +					     vm->composite_fence_ctx,
> +					     vm->composite_fence_seqno++,
> +					     false);
> +			fence = &cf->base;
> +		} else {
> +			fence = &ifence->base.base;
> +		}
>   	}
>   
> -	dma_resv_add_fence(xe_vm_resv(vm), fence,
> -			   pt_update_ops->wait_vm_bookkeep ?
> -			   DMA_RESV_USAGE_KERNEL :
> -			   DMA_RESV_USAGE_BOOKKEEP);
> +	if (!mfence) {
> +		dma_resv_add_fence(xe_vm_resv(vm), fence,
> +				   pt_update_ops->wait_vm_bookkeep ?
> +				   DMA_RESV_USAGE_KERNEL :
> +				   DMA_RESV_USAGE_BOOKKEEP);
>   
> -	list_for_each_entry(op, &vops->list, link)
> -		op_commit(vops->vm, tile, pt_update_ops, op, fence);
> +		list_for_each_entry(op, &vops->list, link)
> +			op_commit(vops->vm, tile, pt_update_ops, op, fence, NULL);
> +	} else {
> +		dma_resv_add_fence(xe_vm_resv(vm), &ifence->base.base,
> +				   pt_update_ops->wait_vm_bookkeep ?
> +				   DMA_RESV_USAGE_KERNEL :
> +				   DMA_RESV_USAGE_BOOKKEEP);
> +
> +		dma_resv_add_fence(xe_vm_resv(vm), &mfence->base.base,
> +				   pt_update_ops->wait_vm_bookkeep ?
> +				   DMA_RESV_USAGE_KERNEL :
> +				   DMA_RESV_USAGE_BOOKKEEP);
> +
> +		list_for_each_entry(op, &vops->list, link)
> +			op_commit(vops->vm, tile, pt_update_ops, op,
> +				  &ifence->base.base, &mfence->base.base);
> +	}
>   
>   	if (pt_update_ops->needs_userptr_lock)
>   		up_read(&vm->userptr.notifier_lock);
> @@ -2049,6 +2121,9 @@ xe_pt_update_ops_run(struct xe_tile *tile, struct xe_vma_ops *vops)
>   free_rfence:
>   	kfree(rfence);
>   free_ifence:
> +	kfree(cf);
> +	kfree(fences);
> +	kfree(mfence);
>   	kfree(ifence);
>   kill_vm_tile1:
>   	if (err != -EAGAIN && tile->id)