From: Julian Wiedmann Date: Mon, 23 Dec 2019 15:22:26 +0100 Subject: s390/qeth: use napi_gro_frags() for SG skbs Git-commit: dcdcf8670dad7547cff59ef9ddd7312fc706464a Patch-mainline: v5.6-rc1 References: jsc#SLE-13690 For non-linear packets, get the skb for attaching the page fragments from napi_get_frags() so that it can be recycled during GRO. Signed-off-by: Julian Wiedmann Signed-off-by: David S. Miller Acked-by: Petr Tesarik --- drivers/s390/net/qeth_core_main.c | 67 ++++++++++++++++++++++++++++---------- 1 file changed, 50 insertions(+), 17 deletions(-) --- a/drivers/s390/net/qeth_core_main.c +++ b/drivers/s390/net/qeth_core_main.c @@ -5095,8 +5095,9 @@ static void qeth_l3_rebuild_skb(struct q #endif static void qeth_receive_skb(struct qeth_card *card, struct sk_buff *skb, - struct qeth_hdr *hdr) + struct qeth_hdr *hdr, bool uses_frags) { + struct napi_struct *napi = &card->napi; bool is_cso; switch (hdr->hdr.l2.id) { @@ -5119,7 +5120,10 @@ static void qeth_receive_skb(struct qeth break; default: /* never happens */ - dev_kfree_skb_any(skb); + if (uses_frags) + napi_free_frags(napi); + else + dev_kfree_skb_any(skb); return; } @@ -5130,8 +5134,6 @@ static void qeth_receive_skb(struct qeth skb->ip_summed = CHECKSUM_NONE; } - skb->protocol = eth_type_trans(skb, skb->dev); - QETH_CARD_STAT_ADD(card, rx_bytes, skb->len); QETH_CARD_STAT_INC(card, rx_packets); if (skb_is_nonlinear(skb)) { @@ -5140,7 +5142,12 @@ static void qeth_receive_skb(struct qeth skb_shinfo(skb)->nr_frags); } - napi_gro_receive(&card->napi, skb); + if (uses_frags) { + napi_gro_frags(napi); + } else { + skb->protocol = eth_type_trans(skb, skb->dev); + napi_gro_receive(napi, skb); + } } static void qeth_create_skb_frag(struct sk_buff *skb, char *data, int data_len) @@ -5166,7 +5173,9 @@ static int qeth_extract_skb(struct qeth_ { struct qdio_buffer_element *element = *__element; struct qdio_buffer *buffer = qethbuffer->buffer; + struct napi_struct *napi = &card->napi; unsigned int linear_len = 0; + bool uses_frags = false; int offset = *__offset; bool use_rx_sg = false; unsigned int headroom; @@ -5242,21 +5251,42 @@ next_packet: !atomic_read(&card->force_alloc_skb) && !IS_OSN(card)); - if (use_rx_sg && qethbuffer->rx_skb) { + if (use_rx_sg) { /* QETH_CQ_ENABLED only: */ - skb = qethbuffer->rx_skb; - qethbuffer->rx_skb = NULL; - } else { - if (!use_rx_sg) - linear_len = skb_len; - skb = napi_alloc_skb(&card->napi, linear_len + headroom); + if (qethbuffer->rx_skb) { + skb = qethbuffer->rx_skb; + qethbuffer->rx_skb = NULL; + goto use_skb; + } + + skb = napi_get_frags(napi); + if (!skb) { + /* -ENOMEM, no point in falling back further. */ + QETH_CARD_STAT_INC(card, rx_dropped_nomem); + goto walk_packet; + } + + if (skb_tailroom(skb) >= linear_len + headroom) { + uses_frags = true; + goto use_skb; + } + + netdev_info_once(card->dev, + "Insufficient linear space in NAPI frags skb, need %u but have %u\n", + linear_len + headroom, skb_tailroom(skb)); + /* Shouldn't happen. Don't optimize, fall back to linear skb. */ } - if (!skb) + linear_len = skb_len; + skb = napi_alloc_skb(napi, linear_len + headroom); + if (!skb) { QETH_CARD_STAT_INC(card, rx_dropped_nomem); - else if (headroom) - skb_reserve(skb, headroom); + goto walk_packet; + } +use_skb: + if (headroom) + skb_reserve(skb, headroom); walk_packet: while (skb_len) { int data_len = min(skb_len, (int)(element->length - offset)); @@ -5289,7 +5319,10 @@ walk_packet: QETH_CARD_TEXT(card, 4, "unexeob"); QETH_CARD_HEX(card, 2, buffer, sizeof(void *)); if (skb) { - dev_kfree_skb_any(skb); + if (uses_frags) + napi_free_frags(napi); + else + dev_kfree_skb_any(skb); QETH_CARD_STAT_INC(card, rx_length_errors); } @@ -5307,7 +5340,7 @@ walk_packet: *__element = element; *__offset = offset; - qeth_receive_skb(card, skb, hdr); + qeth_receive_skb(card, skb, hdr, uses_frags); return 0; }