From a647a02512ca346bb399d7dc4f57e327f2475286 Mon Sep 17 00:00:00 2001 From: Julian Wiedmann Date: Wed, 11 Jul 2018 17:42:46 +0200 Subject: [PATCH] s390/qeth: speed-up L3 IQD xmit This implements a new xmit path for L3 HiperSockets, which carves the HW header from skb headroom instead of allocating it from the hdr cache. It also adds NETIF_F_SG support. The delta in qeth_l3_xmit() is all just removal of IQD-specific code and some minor consolidation. Signed-off-by: Julian Wiedmann Signed-off-by: David S. Miller --- drivers/s390/net/qeth_l3_main.c | 211 +++++++++++++++++++------------- 1 file changed, 128 insertions(+), 83 deletions(-) diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c index b5a54cc07017..0863ffa9ab59 100644 --- a/drivers/s390/net/qeth_l3_main.c +++ b/drivers/s390/net/qeth_l3_main.c @@ -2000,19 +2000,18 @@ static int qeth_l3_get_cast_type(struct sk_buff *skb) return RTN_UNICAST; } -static void qeth_l3_fill_af_iucv_hdr(struct qeth_card *card, - struct qeth_hdr *hdr, struct sk_buff *skb) +static void qeth_l3_fill_af_iucv_hdr(struct qeth_hdr *hdr, struct sk_buff *skb, + unsigned int data_len) { char daddr[16]; struct af_iucv_trans_hdr *iucv_hdr; memset(hdr, 0, sizeof(struct qeth_hdr)); hdr->hdr.l3.id = QETH_HEADER_TYPE_LAYER3; - hdr->hdr.l3.ext_flags = 0; - hdr->hdr.l3.length = skb->len - ETH_HLEN; + hdr->hdr.l3.length = data_len; hdr->hdr.l3.flags = QETH_HDR_IPV6 | QETH_CAST_UNICAST; - iucv_hdr = (struct af_iucv_trans_hdr *) (skb->data + ETH_HLEN); + iucv_hdr = (struct af_iucv_trans_hdr *)(skb_mac_header(skb) + ETH_HLEN); memset(daddr, 0, sizeof(daddr)); daddr[0] = 0xfe; daddr[1] = 0x80; @@ -2156,63 +2155,122 @@ static int qeth_l3_get_elements_no_tso(struct qeth_card *card, return elements; } +static int qeth_l3_xmit_offload(struct qeth_card *card, struct sk_buff *skb, + struct qeth_qdio_out_q *queue, int ipv, + int cast_type) +{ + const unsigned int hw_hdr_len = sizeof(struct qeth_hdr); + unsigned int frame_len, nr_frags; + unsigned char eth_hdr[ETH_HLEN]; + unsigned int hdr_elements = 0; + struct qeth_hdr *hdr = NULL; + unsigned int hd_len = 0; + int push_len, rc; + + /* compress skb to fit into one IO buffer: */ + if (!qeth_get_elements_no(card, skb, 0, 0)) { + rc = skb_linearize(skb); + + if (card->options.performance_stats) { + if (rc) + card->perf_stats.tx_linfail++; + else + card->perf_stats.tx_lin++; + } + if (rc) + return rc; + } + + /* re-use the L2 header area for the HW header: */ + rc = skb_cow_head(skb, hw_hdr_len - ETH_HLEN); + if (rc) + return rc; + skb_copy_from_linear_data(skb, eth_hdr, ETH_HLEN); + skb_pull(skb, ETH_HLEN); + frame_len = skb->len; + nr_frags = skb_shinfo(skb)->nr_frags; + + push_len = qeth_push_hdr(skb, &hdr, hw_hdr_len); + if (push_len < 0) + return push_len; + if (!push_len) { + /* hdr was added discontiguous from skb->data */ + hd_len = hw_hdr_len; + hdr_elements = 1; + } + + if (!qeth_get_elements_no(card, skb, hdr_elements, 0)) { + rc = -E2BIG; + goto out; + } + + if (skb->protocol == htons(ETH_P_AF_IUCV)) + qeth_l3_fill_af_iucv_hdr(hdr, skb, frame_len); + else + qeth_l3_fill_header(card, hdr, skb, ipv, cast_type, frame_len); + + rc = qeth_do_send_packet_fast(queue, skb, hdr, 0, hd_len); +out: + if (!rc) { + if (card->options.performance_stats && nr_frags) { + card->perf_stats.sg_skbs_sent++; + /* nr_frags + skb->data */ + card->perf_stats.sg_frags_sent += nr_frags + 1; + } + } else { + if (!push_len) + kmem_cache_free(qeth_core_header_cache, hdr); + if (rc == -EBUSY) { + /* roll back to ETH header */ + skb_pull(skb, push_len); + skb_push(skb, ETH_HLEN); + skb_copy_to_linear_data(skb, eth_hdr, ETH_HLEN); + } + } + return rc; +} + static int qeth_l3_xmit(struct qeth_card *card, struct sk_buff *skb, struct qeth_qdio_out_q *queue, int ipv, int cast_type) { - int rc; + unsigned int hd_len, nr_frags; + int elements, len, rc; __be16 *tag; struct qeth_hdr *hdr = NULL; int hdr_elements = 0; - int elements; struct sk_buff *new_skb = NULL; int tx_bytes = skb->len; - unsigned int hd_len = 0; bool use_tso; - int data_offset = -1; - unsigned int nr_frags; /* Ignore segment size from skb_is_gso(), 1 page is always used. */ use_tso = skb_is_gso(skb) && (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4); - if (card->info.type == QETH_CARD_TYPE_IQD) { - new_skb = skb; - data_offset = ETH_HLEN; - hd_len = sizeof(*hdr); - hdr = kmem_cache_alloc(qeth_core_header_cache, GFP_ATOMIC); - if (!hdr) - return -ENOMEM; - hdr_elements++; - } else { - /* create a clone with writeable headroom */ - new_skb = skb_realloc_headroom(skb, sizeof(struct qeth_hdr_tso) - + VLAN_HLEN); - if (!new_skb) - return -ENOMEM; + /* create a clone with writeable headroom */ + new_skb = skb_realloc_headroom(skb, sizeof(struct qeth_hdr_tso) + + VLAN_HLEN); + if (!new_skb) + return -ENOMEM; - if (ipv == 4) { - skb_pull(new_skb, ETH_HLEN); - } - - if (ipv != 4 && skb_vlan_tag_present(new_skb)) { - skb_push(new_skb, VLAN_HLEN); - skb_copy_to_linear_data(new_skb, new_skb->data + 4, 4); - skb_copy_to_linear_data_offset(new_skb, 4, - new_skb->data + 8, 4); - skb_copy_to_linear_data_offset(new_skb, 8, - new_skb->data + 12, 4); - tag = (__be16 *)(new_skb->data + 12); - *tag = cpu_to_be16(ETH_P_8021Q); - *(tag + 1) = cpu_to_be16(skb_vlan_tag_get(new_skb)); - } + if (ipv == 4) { + skb_pull(new_skb, ETH_HLEN); + } else if (skb_vlan_tag_present(new_skb)) { + skb_push(new_skb, VLAN_HLEN); + skb_copy_to_linear_data(new_skb, new_skb->data + 4, 4); + skb_copy_to_linear_data_offset(new_skb, 4, + new_skb->data + 8, 4); + skb_copy_to_linear_data_offset(new_skb, 8, + new_skb->data + 12, 4); + tag = (__be16 *)(new_skb->data + 12); + *tag = cpu_to_be16(ETH_P_8021Q); + *(tag + 1) = cpu_to_be16(skb_vlan_tag_get(new_skb)); } /* fix hardware limitation: as long as we do not have sbal * chaining we can not send long frag lists */ - if ((card->info.type != QETH_CARD_TYPE_IQD) && - ((use_tso && !qeth_l3_get_elements_no_tso(card, new_skb, 1)) || - (!use_tso && !qeth_get_elements_no(card, new_skb, 0, 0)))) { + if ((use_tso && !qeth_l3_get_elements_no_tso(card, new_skb, 1)) || + (!use_tso && !qeth_get_elements_no(card, new_skb, 0, 0))) { rc = skb_linearize(new_skb); if (card->options.performance_stats) { @@ -2234,20 +2292,9 @@ static int qeth_l3_xmit(struct qeth_card *card, struct sk_buff *skb, qeth_tso_fill_header(card, hdr, new_skb); hdr_elements++; } else { - if (data_offset < 0) { - hdr = skb_push(new_skb, sizeof(struct qeth_hdr)); - qeth_l3_fill_header(card, hdr, new_skb, ipv, cast_type, - new_skb->len - - sizeof(struct qeth_hdr)); - } else { - if (be16_to_cpu(new_skb->protocol) == ETH_P_AF_IUCV) - qeth_l3_fill_af_iucv_hdr(card, hdr, new_skb); - else { - qeth_l3_fill_header(card, hdr, new_skb, ipv, - cast_type, - new_skb->len - data_offset); - } - } + hdr = skb_push(new_skb, sizeof(struct qeth_hdr)); + qeth_l3_fill_header(card, hdr, new_skb, ipv, cast_type, + new_skb->len - sizeof(struct qeth_hdr)); if (new_skb->ip_summed == CHECKSUM_PARTIAL) { qeth_tx_csum(new_skb, &hdr->hdr.l3.ext_flags, ipv); @@ -2258,34 +2305,28 @@ static int qeth_l3_xmit(struct qeth_card *card, struct sk_buff *skb, elements = use_tso ? qeth_l3_get_elements_no_tso(card, new_skb, hdr_elements) : - qeth_get_elements_no(card, new_skb, hdr_elements, - (data_offset > 0) ? data_offset : 0); + qeth_get_elements_no(card, new_skb, hdr_elements, 0); if (!elements) { rc = -E2BIG; goto out; } elements += hdr_elements; - if (card->info.type != QETH_CARD_TYPE_IQD) { - int len; - if (use_tso) { - hd_len = sizeof(struct qeth_hdr_tso) + - ip_hdrlen(new_skb) + tcp_hdrlen(new_skb); - len = hd_len; - } else { - len = sizeof(struct qeth_hdr_layer3); - } - - if (qeth_hdr_chk_and_bounce(new_skb, &hdr, len)) { - rc = -EINVAL; - goto out; - } - rc = qeth_do_send_packet(card, queue, new_skb, hdr, hd_len, - hd_len, elements); - } else - rc = qeth_do_send_packet_fast(queue, new_skb, hdr, data_offset, - hd_len); + if (use_tso) { + hd_len = sizeof(struct qeth_hdr_tso) + + ip_hdrlen(new_skb) + tcp_hdrlen(new_skb); + len = hd_len; + } else { + hd_len = 0; + len = sizeof(struct qeth_hdr_layer3); + } + if (qeth_hdr_chk_and_bounce(new_skb, &hdr, len)) { + rc = -EINVAL; + goto out; + } + rc = qeth_do_send_packet(card, queue, new_skb, hdr, hd_len, hd_len, + elements); out: if (!rc) { if (new_skb != skb) @@ -2304,8 +2345,6 @@ out: } else { if (new_skb != skb) dev_kfree_skb_any(new_skb); - if (data_offset >= 0) - kmem_cache_free(qeth_core_header_cache, hdr); } return rc; } @@ -2345,7 +2384,10 @@ static netdev_tx_t qeth_l3_hard_start_xmit(struct sk_buff *skb, } netif_stop_queue(dev); - rc = qeth_l3_xmit(card, skb, queue, ipv, cast_type); + if (IS_IQD(card)) + rc = qeth_l3_xmit_offload(card, skb, queue, ipv, cast_type); + else + rc = qeth_l3_xmit(card, skb, queue, ipv, cast_type); if (!rc) { card->stats.tx_packets++; @@ -2503,9 +2545,6 @@ static int qeth_l3_setup_netdev(struct qeth_card *card) if (!(card->info.unique_id & UNIQUE_ID_NOT_BY_CARD)) card->dev->dev_id = card->info.unique_id & 0xffff; - card->dev->hw_features |= NETIF_F_SG; - card->dev->vlan_features |= NETIF_F_SG; - if (!card->info.guestlan) { card->dev->features |= NETIF_F_SG; card->dev->hw_features |= NETIF_F_TSO | @@ -2524,7 +2563,10 @@ static int qeth_l3_setup_netdev(struct qeth_card *card) if (!card->dev) return -ENODEV; card->dev->flags |= IFF_NOARP; + card->dev->priv_flags &= ~IFF_TX_SKB_SHARING; card->dev->netdev_ops = &qeth_l3_netdev_ops; + card->dev->needed_headroom = sizeof(struct qeth_hdr) - ETH_HLEN; + rc = qeth_l3_iqd_read_initial_mac(card); if (rc) return rc; @@ -2543,6 +2585,9 @@ static int qeth_l3_setup_netdev(struct qeth_card *card) card->dev->features |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX | NETIF_F_HW_VLAN_CTAG_FILTER; + card->dev->hw_features |= NETIF_F_SG; + card->dev->vlan_features |= NETIF_F_SG; + netif_keep_dst(card->dev); if (card->dev->hw_features & NETIF_F_TSO) netif_set_gso_max_size(card->dev,