Commit 7abd955a authored by Dragos Tatulea's avatar Dragos Tatulea Committed by Saeed Mahameed
Browse files

net/mlx5e: RX, Fix page_pool page fragment tracking for XDP 



Currently mlx5e releases pages directly to the page_pool for XDP_TX and
does page fragment counting for XDP_REDIRECT. RX pages from the
page_pool are leaking on XDP_REDIRECT because the xdp core will release
only one fragment out of MLX5E_PAGECNT_BIAS_MAX and subsequently the page
is marked as "skip release" which avoids the driver release.

A fix would be to take an extra fragment for XDP_REDIRECT and not set the
"skip release" bit so that the release on the driver side can handle the
remaining bias fragments. But this would be a shortsighted solution.
Instead, this patch converges the two XDP paths (XDP_TX and XDP_REDIRECT) to
always do fragment tracking. The "skip release" bit is no longer
necessary for XDP.

Fixes: 6f574284 ("net/mlx5e: RX, Enable skb page recycling through the page_pool")
Signed-off-by: default avatarDragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: default avatarTariq Toukan <tariqt@nvidia.com>
Signed-off-by: default avatarSaeed Mahameed <saeedm@nvidia.com>
parent 6496357a

drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c

+1 −2
Original line number Diff line number Diff line
@@ -662,8 +662,7 @@ static void mlx5e_free_xdpsq_desc(struct mlx5e_xdpsq *sq, 
				/* No need to check ((page->pp_magic & ~0x3UL) == PP_SIGNATURE)

				 * as we know this is a page_pool page.

				 */

				page_pool_put_defragged_page(page->pp,

							     page, -1, true);

				page_pool_recycle_direct(page->pp, page);

			} while (++n < num);



			break;

drivers/net/ethernet/mellanox/mlx5/core/en_rx.c

+12 −20
Original line number Diff line number Diff line
@@ -1751,11 +1751,11 @@ mlx5e_skb_from_cqe_nonlinear(struct mlx5e_rq *rq, struct mlx5e_wqe_frag_info *wi 


	prog = rcu_dereference(rq->xdp_prog);

	if (prog && mlx5e_xdp_handle(rq, prog, &mxbuf)) {

		if (test_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags)) {

		if (__test_and_clear_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags)) {

			struct mlx5e_wqe_frag_info *pwi;



			for (pwi = head_wi; pwi < wi; pwi++)

				pwi->flags |= BIT(MLX5E_WQE_FRAG_SKIP_RELEASE);

				pwi->frag_page->frags++;

		}

		return NULL; /* page/packet was consumed by XDP */

	}
@@ -1825,12 +1825,8 @@ static void mlx5e_handle_rx_cqe(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe) 
			      rq, wi, cqe, cqe_bcnt);

	if (!skb) {

		/* probably for XDP */

		if (__test_and_clear_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags)) {

			/* do not return page to cache,

			 * it will be returned on XDP_TX completion.

			 */

			wi->flags |= BIT(MLX5E_WQE_FRAG_SKIP_RELEASE);

		}

		if (__test_and_clear_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags))

			wi->frag_page->frags++;

		goto wq_cyc_pop;

	}
@@ -1876,12 +1872,8 @@ static void mlx5e_handle_rx_cqe_rep(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe) 
			      rq, wi, cqe, cqe_bcnt);

	if (!skb) {

		/* probably for XDP */

		if (__test_and_clear_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags)) {

			/* do not return page to cache,

			 * it will be returned on XDP_TX completion.

			 */

			wi->flags |= BIT(MLX5E_WQE_FRAG_SKIP_RELEASE);

		}

		if (__test_and_clear_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags))

			wi->frag_page->frags++;

		goto wq_cyc_pop;

	}
@@ -2060,12 +2052,12 @@ mlx5e_skb_from_cqe_mpwrq_nonlinear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *w 
	if (prog) {

		if (mlx5e_xdp_handle(rq, prog, &mxbuf)) {

			if (__test_and_clear_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags)) {

				int i;

				struct mlx5e_frag_page *pfp;



				for (i = 0; i < sinfo->nr_frags; i++)

					/* non-atomic */

					__set_bit(page_idx + i, wi->skip_release_bitmap);

				return NULL;

				for (pfp = head_page; pfp < frag_page; pfp++)

					pfp->frags++;



				wi->linear_page.frags++;

			}

			mlx5e_page_release_fragmented(rq, &wi->linear_page);

			return NULL; /* page/packet was consumed by XDP */
@@ -2163,7 +2155,7 @@ mlx5e_skb_from_cqe_mpwrq_linear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi, 
				 cqe_bcnt, &mxbuf);

		if (mlx5e_xdp_handle(rq, prog, &mxbuf)) {

			if (__test_and_clear_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags))

				__set_bit(page_idx, wi->skip_release_bitmap); /* non-atomic */

				frag_page->frags++;

			return NULL; /* page/packet was consumed by XDP */

		}