Re: [PATCH] drm/xe/migrate: Parameterize ccs and bo data clear in xe_migrate_clear()

[Nirmoy Das <nirmoy.das@intel.com>]

Extracting this from https://patchwork.freedesktop.org/series/136277/ as 
there is a regression in performance number on drm-tip.

I think it will take some time to find out what is going on. This patch 
can be applied independently sending it separately.


Regards,

Nirmoy

On 8/10/2024 12:03 AM, Nirmoy Das wrote:
> Parameterize clearing ccs and bo data in xe_migrate_clear() which  higher
> layers can utilize. This patch will be used later on when doing bo data
> clear for igfx as well.
>
> v2: Replace multiple params with flags in xe_migrate_clear (Matt B)
> v3: s/CLEAR_BO_DATA_FLAG_*/XE_MIGRATE_CLEAR_FLAG_* and move to
>      xe_migrate.h. other nits(Matt B)
>
> Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
> Cc: Matthew Auld <matthew.auld@intel.com>
> Cc: Matthew Brost <matthew.brost@intel.com>
> Cc: "Thomas Hellström" <thomas.hellstrom@linux.intel.com>
> Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
> Signed-off-by: Akshata Jahagirdar <akshata.jahagirdar@intel.com>
> Reviewed-by: Matthew Auld <matthew.auld@intel.com>
> ---
>   drivers/gpu/drm/xe/tests/xe_bo.c      |  3 ++-
>   drivers/gpu/drm/xe/tests/xe_migrate.c | 12 ++++++++----
>   drivers/gpu/drm/xe/xe_bo.c            | 12 ++++++++++--
>   drivers/gpu/drm/xe/xe_migrate.c       | 27 +++++++++++++++++++--------
>   drivers/gpu/drm/xe/xe_migrate.h       |  7 ++++++-
>   5 files changed, 45 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/gpu/drm/xe/tests/xe_bo.c b/drivers/gpu/drm/xe/tests/xe_bo.c
> index 1768483da1b7..df9fd907edd4 100644
> --- a/drivers/gpu/drm/xe/tests/xe_bo.c
> +++ b/drivers/gpu/drm/xe/tests/xe_bo.c
> @@ -36,7 +36,8 @@ static int ccs_test_migrate(struct xe_tile *tile, struct xe_bo *bo,
>   
>   	/* Optionally clear bo *and* CCS data in VRAM. */
>   	if (clear) {
> -		fence = xe_migrate_clear(tile->migrate, bo, bo->ttm.resource);
> +		fence = xe_migrate_clear(tile->migrate, bo, bo->ttm.resource,
> +					 XE_MIGRATE_CLEAR_FLAG_FULL);
>   		if (IS_ERR(fence)) {
>   			KUNIT_FAIL(test, "Failed to submit bo clear.\n");
>   			return PTR_ERR(fence);
> diff --git a/drivers/gpu/drm/xe/tests/xe_migrate.c b/drivers/gpu/drm/xe/tests/xe_migrate.c
> index 4344a1724029..47ae9d0b8864 100644
> --- a/drivers/gpu/drm/xe/tests/xe_migrate.c
> +++ b/drivers/gpu/drm/xe/tests/xe_migrate.c
> @@ -105,7 +105,8 @@ static void test_copy(struct xe_migrate *m, struct xe_bo *bo,
>   	}
>   
>   	xe_map_memset(xe, &remote->vmap, 0, 0xd0, remote->size);
> -	fence = xe_migrate_clear(m, remote, remote->ttm.resource);
> +	fence = xe_migrate_clear(m, remote, remote->ttm.resource,
> +				 XE_MIGRATE_CLEAR_FLAG_FULL);
>   	if (!sanity_fence_failed(xe, fence, big ? "Clearing remote big bo" :
>   				 "Clearing remote small bo", test)) {
>   		retval = xe_map_rd(xe, &remote->vmap, 0, u64);
> @@ -279,7 +280,8 @@ static void xe_migrate_sanity_test(struct xe_migrate *m, struct kunit *test)
>   	kunit_info(test, "Clearing small buffer object\n");
>   	xe_map_memset(xe, &tiny->vmap, 0, 0x22, tiny->size);
>   	expected = 0;
> -	fence = xe_migrate_clear(m, tiny, tiny->ttm.resource);
> +	fence = xe_migrate_clear(m, tiny, tiny->ttm.resource,
> +				 XE_MIGRATE_CLEAR_FLAG_FULL);
>   	if (sanity_fence_failed(xe, fence, "Clearing small bo", test))
>   		goto out;
>   
> @@ -300,7 +302,8 @@ static void xe_migrate_sanity_test(struct xe_migrate *m, struct kunit *test)
>   	kunit_info(test, "Clearing big buffer object\n");
>   	xe_map_memset(xe, &big->vmap, 0, 0x11, big->size);
>   	expected = 0;
> -	fence = xe_migrate_clear(m, big, big->ttm.resource);
> +	fence = xe_migrate_clear(m, big, big->ttm.resource,
> +				 XE_MIGRATE_CLEAR_FLAG_FULL);
>   	if (sanity_fence_failed(xe, fence, "Clearing big bo", test))
>   		goto out;
>   
> @@ -603,7 +606,8 @@ static void test_clear(struct xe_device *xe, struct xe_tile *tile,
>   
>   	kunit_info(test, "Clear vram buffer object\n");
>   	expected = 0x0000000000000000;
> -	fence = xe_migrate_clear(tile->migrate, vram_bo, vram_bo->ttm.resource);
> +	fence = xe_migrate_clear(tile->migrate, vram_bo, vram_bo->ttm.resource,
> +				 XE_MIGRATE_CLEAR_FLAG_FULL);
>   	if (sanity_fence_failed(xe, fence, "Clear vram_bo", test))
>   		return;
>   	dma_fence_put(fence);
> diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c
> index 3295bc92d7aa..56a089aa3916 100644
> --- a/drivers/gpu/drm/xe/xe_bo.c
> +++ b/drivers/gpu/drm/xe/xe_bo.c
> @@ -793,8 +793,16 @@ static int xe_bo_move(struct ttm_buffer_object *ttm_bo, bool evict,
>   			}
>   		}
>   	} else {
> -		if (move_lacks_source)
> -			fence = xe_migrate_clear(migrate, bo, new_mem);
> +		if (move_lacks_source) {
> +			u32 flags = 0;
> +
> +			if (mem_type_is_vram(new_mem->mem_type))
> +				flags |= XE_MIGRATE_CLEAR_FLAG_FULL;
> +			else if (handle_system_ccs)
> +				flags |= XE_MIGRATE_CLEAR_FLAG_CCS_DATA;
> +
> +			fence = xe_migrate_clear(migrate, bo, new_mem, flags);
> +		}
>   		else
>   			fence = xe_migrate_copy(migrate, bo, bo, old_mem,
>   						new_mem, handle_system_ccs);
> diff --git a/drivers/gpu/drm/xe/xe_migrate.c b/drivers/gpu/drm/xe/xe_migrate.c
> index 6f24aaf58252..a2d0ce3c59bf 100644
> --- a/drivers/gpu/drm/xe/xe_migrate.c
> +++ b/drivers/gpu/drm/xe/xe_migrate.c
> @@ -1037,9 +1037,11 @@ static void emit_clear(struct xe_gt *gt, struct xe_bb *bb, u64 src_ofs,
>    * @m: The migration context.
>    * @bo: The buffer object @dst is currently bound to.
>    * @dst: The dst TTM resource to be cleared.
> + * @clear_flags: flags to specify which data to clear: CCS, BO, or both.
>    *
> - * Clear the contents of @dst to zero. On flat CCS devices,
> - * the CCS metadata is cleared to zero as well on VRAM destinations.
> + * Clear the contents of @dst to zero when XE_MIGRATE_CLEAR_FLAG_BO_DATA is set.
> + * On flat CCS devices, the CCS metadata is cleared to zero with XE_MIGRATE_CLEAR_FLAG_CCS_DATA.
> + * Set XE_MIGRATE_CLEAR_FLAG_FULL to clear bo as well as CCS metadata.
>    * TODO: Eliminate the @bo argument.
>    *
>    * Return: Pointer to a dma_fence representing the last clear batch, or
> @@ -1048,18 +1050,27 @@ static void emit_clear(struct xe_gt *gt, struct xe_bb *bb, u64 src_ofs,
>    */
>   struct dma_fence *xe_migrate_clear(struct xe_migrate *m,
>   				   struct xe_bo *bo,
> -				   struct ttm_resource *dst)
> +				   struct ttm_resource *dst,
> +				   u32 clear_flags)
>   {
>   	bool clear_vram = mem_type_is_vram(dst->mem_type);
> +	bool clear_bo_data = XE_MIGRATE_CLEAR_FLAG_BO_DATA & clear_flags;
> +	bool clear_ccs = XE_MIGRATE_CLEAR_FLAG_CCS_DATA & clear_flags;
>   	struct xe_gt *gt = m->tile->primary_gt;
>   	struct xe_device *xe = gt_to_xe(gt);
> -	bool clear_system_ccs = (xe_bo_needs_ccs_pages(bo) && !IS_DGFX(xe)) ? true : false;
> +	bool clear_only_system_ccs = false;
>   	struct dma_fence *fence = NULL;
>   	u64 size = bo->size;
>   	struct xe_res_cursor src_it;
>   	struct ttm_resource *src = dst;
>   	int err;
>   
> +	if (WARN_ON(!clear_bo_data && !clear_ccs))
> +		return NULL;
> +
> +	if (!clear_bo_data && clear_ccs && !IS_DGFX(xe))
> +		clear_only_system_ccs = true;
> +
>   	if (!clear_vram)
>   		xe_res_first_sg(xe_bo_sg(bo), 0, bo->size, &src_it);
>   	else
> @@ -1085,7 +1096,7 @@ struct dma_fence *xe_migrate_clear(struct xe_migrate *m,
>   		batch_size = 2 +
>   			pte_update_size(m, pte_flags, src, &src_it,
>   					&clear_L0, &clear_L0_ofs, &clear_L0_pt,
> -					clear_system_ccs ? 0 : emit_clear_cmd_len(gt), 0,
> +					clear_bo_data ? emit_clear_cmd_len(gt) : 0, 0,
>   					avail_pts);
>   
>   		if (xe_migrate_needs_ccs_emit(xe))
> @@ -1107,13 +1118,13 @@ struct dma_fence *xe_migrate_clear(struct xe_migrate *m,
>   		if (clear_vram && xe_migrate_allow_identity(clear_L0, &src_it))
>   			xe_res_next(&src_it, clear_L0);
>   		else
> -			emit_pte(m, bb, clear_L0_pt, clear_vram, clear_system_ccs,
> +			emit_pte(m, bb, clear_L0_pt, clear_vram, clear_only_system_ccs,
>   				 &src_it, clear_L0, dst);
>   
>   		bb->cs[bb->len++] = MI_BATCH_BUFFER_END;
>   		update_idx = bb->len;
>   
> -		if (!clear_system_ccs)
> +		if (clear_bo_data)
>   			emit_clear(gt, bb, clear_L0_ofs, clear_L0, XE_PAGE_SIZE, clear_vram);
>   
>   		if (xe_migrate_needs_ccs_emit(xe)) {
> @@ -1172,7 +1183,7 @@ struct dma_fence *xe_migrate_clear(struct xe_migrate *m,
>   		return ERR_PTR(err);
>   	}
>   
> -	if (clear_system_ccs)
> +	if (clear_ccs)
>   		bo->ccs_cleared = true;
>   
>   	return fence;
> diff --git a/drivers/gpu/drm/xe/xe_migrate.h b/drivers/gpu/drm/xe/xe_migrate.h
> index 453e0ecf5034..7929cc2425e8 100644
> --- a/drivers/gpu/drm/xe/xe_migrate.h
> +++ b/drivers/gpu/drm/xe/xe_migrate.h
> @@ -102,9 +102,14 @@ struct dma_fence *xe_migrate_copy(struct xe_migrate *m,
>   				  struct ttm_resource *dst,
>   				  bool copy_only_ccs);
>   
> +#define XE_MIGRATE_CLEAR_FLAG_BO_DATA		BIT(0)
> +#define XE_MIGRATE_CLEAR_FLAG_CCS_DATA		BIT(1)
> +#define XE_MIGRATE_CLEAR_FLAG_FULL	(XE_MIGRATE_CLEAR_FLAG_BO_DATA | \
> +					XE_MIGRATE_CLEAR_FLAG_CCS_DATA)
>   struct dma_fence *xe_migrate_clear(struct xe_migrate *m,
>   				   struct xe_bo *bo,
> -				   struct ttm_resource *dst);
> +				   struct ttm_resource *dst,
> +				   u32 clear_flags);
>   
>   struct xe_vm *xe_migrate_get_vm(struct xe_migrate *m);
>