Commit da43f0aa authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

Merge branch 'mvneta-access-skb_shared_info-only-on-last-frag' 

Lorenzo Bianconi says:

====================
mvneta: access skb_shared_info only on last frag

Build skb_shared_info on mvneta_rx_swbm stack and sync it to xdp_buff
skb_shared_info area only on the last fragment.
Avoid avoid unnecessary xdp_buff initialization in mvneta_rx_swbm routine.
This a preliminary series to complete xdp multi-buff in mvneta driver.
====================

Link: https://lore.kernel.org/r/cover.1605889258.git.lorenzo@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parents 9a71baf7 039fbc47

drivers/net/ethernet/marvell/mvneta.c

+35 −20
Original line number Diff line number Diff line
@@ -2033,16 +2033,16 @@ int mvneta_rx_refill_queue(struct mvneta_port *pp, struct mvneta_rx_queue *rxq) 


static void

mvneta_xdp_put_buff(struct mvneta_port *pp, struct mvneta_rx_queue *rxq,

		    struct xdp_buff *xdp, int sync_len, bool napi)

		    struct xdp_buff *xdp, struct skb_shared_info *sinfo,

		    int sync_len)

{

	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);

	int i;



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

		page_pool_put_full_page(rxq->page_pool,

					skb_frag_page(&sinfo->frags[i]), napi);

					skb_frag_page(&sinfo->frags[i]), true);

	page_pool_put_page(rxq->page_pool, virt_to_head_page(xdp->data),

			   sync_len, napi);

			   sync_len, true);

}



static int
@@ -2179,6 +2179,7 @@ mvneta_run_xdp(struct mvneta_port *pp, struct mvneta_rx_queue *rxq, 
	       struct bpf_prog *prog, struct xdp_buff *xdp,

	       u32 frame_sz, struct mvneta_stats *stats)

{

	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);

	unsigned int len, data_len, sync;

	u32 ret, act;
@@ -2199,7 +2200,7 @@ mvneta_run_xdp(struct mvneta_port *pp, struct mvneta_rx_queue *rxq, 


		err = xdp_do_redirect(pp->dev, xdp, prog);

		if (unlikely(err)) {

			mvneta_xdp_put_buff(pp, rxq, xdp, sync, true);

			mvneta_xdp_put_buff(pp, rxq, xdp, sinfo, sync);

			ret = MVNETA_XDP_DROPPED;

		} else {

			ret = MVNETA_XDP_REDIR;
@@ -2210,7 +2211,7 @@ mvneta_run_xdp(struct mvneta_port *pp, struct mvneta_rx_queue *rxq, 
	case XDP_TX:

		ret = mvneta_xdp_xmit_back(pp, xdp);

		if (ret != MVNETA_XDP_TX)

			mvneta_xdp_put_buff(pp, rxq, xdp, sync, true);

			mvneta_xdp_put_buff(pp, rxq, xdp, sinfo, sync);

		break;

	default:

		bpf_warn_invalid_xdp_action(act);
@@ -2219,7 +2220,7 @@ mvneta_run_xdp(struct mvneta_port *pp, struct mvneta_rx_queue *rxq, 
		trace_xdp_exception(pp->dev, prog, act);

		fallthrough;

	case XDP_DROP:

		mvneta_xdp_put_buff(pp, rxq, xdp, sync, true);

		mvneta_xdp_put_buff(pp, rxq, xdp, sinfo, sync);

		ret = MVNETA_XDP_DROPPED;

		stats->xdp_drop++;

		break;
@@ -2277,9 +2278,9 @@ mvneta_swbm_add_rx_fragment(struct mvneta_port *pp, 
			    struct mvneta_rx_desc *rx_desc,

			    struct mvneta_rx_queue *rxq,

			    struct xdp_buff *xdp, int *size,

			    struct skb_shared_info *xdp_sinfo,

			    struct page *page)

{

	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);

	struct net_device *dev = pp->dev;

	enum dma_data_direction dma_dir;

	int data_len, len;
@@ -2297,13 +2298,22 @@ mvneta_swbm_add_rx_fragment(struct mvneta_port *pp, 
				len, dma_dir);

	rx_desc->buf_phys_addr = 0;



	if (data_len > 0 && sinfo->nr_frags < MAX_SKB_FRAGS) {

		skb_frag_t *frag = &sinfo->frags[sinfo->nr_frags];

	if (data_len > 0 && xdp_sinfo->nr_frags < MAX_SKB_FRAGS) {

		skb_frag_t *frag = &xdp_sinfo->frags[xdp_sinfo->nr_frags++];



		skb_frag_off_set(frag, pp->rx_offset_correction);

		skb_frag_size_set(frag, data_len);

		__skb_frag_set_page(frag, page);

		sinfo->nr_frags++;



		/* last fragment */

		if (len == *size) {

			struct skb_shared_info *sinfo;



			sinfo = xdp_get_shared_info_from_buff(xdp);

			sinfo->nr_frags = xdp_sinfo->nr_frags;

			memcpy(sinfo->frags, xdp_sinfo->frags,

			       sinfo->nr_frags * sizeof(skb_frag_t));

		}

	} else {

		page_pool_put_full_page(rxq->page_pool, page, true);

	}
@@ -2347,13 +2357,17 @@ static int mvneta_rx_swbm(struct napi_struct *napi, 
{

	int rx_proc = 0, rx_todo, refill, size = 0;

	struct net_device *dev = pp->dev;

	struct xdp_buff xdp_buf = {

		.frame_sz = PAGE_SIZE,

		.rxq = &rxq->xdp_rxq,

	};

	struct skb_shared_info sinfo;

	struct mvneta_stats ps = {};

	struct bpf_prog *xdp_prog;

	u32 desc_status, frame_sz;

	struct xdp_buff xdp_buf;



	xdp_buf.data_hard_start = NULL;

	xdp_buf.frame_sz = PAGE_SIZE;

	xdp_buf.rxq = &rxq->xdp_rxq;



	sinfo.nr_frags = 0;



	/* Get number of received packets */

	rx_todo = mvneta_rxq_busy_desc_num_get(pp, rxq);
@@ -2393,11 +2407,11 @@ static int mvneta_rx_swbm(struct napi_struct *napi, 
				rx_desc->buf_phys_addr = 0;

				page_pool_put_full_page(rxq->page_pool, page,

							true);

				continue;

				goto next;

			}



			mvneta_swbm_add_rx_fragment(pp, rx_desc, rxq, &xdp_buf,

						    &size, page);

						    &size, &sinfo, page);

		} /* Middle or Last descriptor */



		if (!(rx_status & MVNETA_RXD_LAST_DESC))
@@ -2405,7 +2419,7 @@ static int mvneta_rx_swbm(struct napi_struct *napi, 
			continue;



		if (size) {

			mvneta_xdp_put_buff(pp, rxq, &xdp_buf, -1, true);

			mvneta_xdp_put_buff(pp, rxq, &xdp_buf, &sinfo, -1);

			goto next;

		}
@@ -2417,7 +2431,7 @@ static int mvneta_rx_swbm(struct napi_struct *napi, 
		if (IS_ERR(skb)) {

			struct mvneta_pcpu_stats *stats = this_cpu_ptr(pp->stats);



			mvneta_xdp_put_buff(pp, rxq, &xdp_buf, -1, true);

			mvneta_xdp_put_buff(pp, rxq, &xdp_buf, &sinfo, -1);



			u64_stats_update_begin(&stats->syncp);

			stats->es.skb_alloc_error++;
@@ -2434,11 +2448,12 @@ static int mvneta_rx_swbm(struct napi_struct *napi, 
		napi_gro_receive(napi, skb);

next:

		xdp_buf.data_hard_start = NULL;

		sinfo.nr_frags = 0;

	}

	rcu_read_unlock();



	if (xdp_buf.data_hard_start)

		mvneta_xdp_put_buff(pp, rxq, &xdp_buf, -1, true);

		mvneta_xdp_put_buff(pp, rxq, &xdp_buf, &sinfo, -1);



	if (ps.xdp_redirect)

		xdp_do_flush_map();

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