From 41aeed58af5d1b5d35988c1c82531306fa719a66 Mon Sep 17 00:00:00 2001 From: Eugene Crosser Date: Thu, 16 Jun 2016 16:18:53 +0200 Subject: [PATCH] qeth: clean up condition when tso is used Make conditions under which TSO is activated more stringent. Make calculation of SBALEs required for the skb more accurate. Signed-off-by: Eugene Crosser Signed-off-by: Ursula Braun Signed-off-by: David S. Miller --- drivers/s390/net/qeth_core.h | 6 ++++++ drivers/s390/net/qeth_l3_main.c | 44 ++++++++++++++++++++++------------------- 2 files changed, 30 insertions(+), 20 deletions(-) diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h index eb8f434a2681..c3ab956536ff 100644 --- a/drivers/s390/net/qeth_core.h +++ b/drivers/s390/net/qeth_core.h @@ -19,6 +19,7 @@ #include #include #include +#include #include #include @@ -878,6 +879,11 @@ static inline int qeth_get_ip_version(struct sk_buff *skb) } } +static inline int qeth_get_ip_protocol(struct sk_buff *skb) +{ + return ip_hdr(skb)->protocol; +} + static inline void qeth_put_buffer_pool_entry(struct qeth_card *card, struct qeth_buffer_pool_entry *entry) { diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c index 7c9968adb66d..86b3bc28d9d4 100644 --- a/drivers/s390/net/qeth_l3_main.c +++ b/drivers/s390/net/qeth_l3_main.c @@ -2794,10 +2794,10 @@ static void qeth_tso_fill_header(struct qeth_card *card, } /** - * qeth_get_elements_no_tso() - find number of SBALEs for skb data, inc. frags. - * @card: qeth card structure, to check max. elems. - * @skb: SKB address - * @extra_elems: extra elems needed, to check against max. + * qeth_l3_get_elements_no_tso() - find number of SBALEs for skb data for tso + * @card: qeth card structure, to check max. elems. + * @skb: SKB address + * @extra_elems: extra elems needed, to check against max. * * Returns the number of pages, and thus QDIO buffer elements, needed to cover * skb data, including linear part and fragments, but excluding TCP header. @@ -2806,7 +2806,7 @@ static void qeth_tso_fill_header(struct qeth_card *card, * Returns 0 if it does not. * Note: extra_elems is not included in the returned result. */ -static int qeth_get_elements_no_tso(struct qeth_card *card, +static int qeth_l3_get_elements_no_tso(struct qeth_card *card, struct sk_buff *skb, int extra_elems) { addr_t tcpdptr = (addr_t)tcp_hdr(skb) + tcp_hdrlen(skb); @@ -2841,7 +2841,7 @@ static int qeth_l3_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) qeth_get_priority_queue(card, skb, ipv, cast_type) : card->qdio.default_out_queue]; int tx_bytes = skb->len; - bool large_send; + bool use_tso; int data_offset = -1; int nr_frags; @@ -2866,10 +2866,12 @@ static int qeth_l3_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) card->perf_stats.outbound_start_time = qeth_get_micros(); } - large_send = skb_is_gso(skb); + /* Ignore segment size from skb_is_gso(), 1 page is always used. */ + use_tso = skb_is_gso(skb) && + (qeth_get_ip_protocol(skb) == IPPROTO_TCP) && (ipv == 4); - if ((card->info.type == QETH_CARD_TYPE_IQD) && (!large_send) && - (skb_shinfo(skb)->nr_frags == 0)) { + if ((card->info.type == QETH_CARD_TYPE_IQD) && + !skb_is_nonlinear(skb)) { new_skb = skb; if (new_skb->protocol == ETH_P_AF_IUCV) data_offset = 0; @@ -2913,16 +2915,16 @@ static int qeth_l3_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) /* fix hardware limitation: as long as we do not have sbal * chaining we can not send long frag lists */ - if (large_send) { - if (!qeth_get_elements_no_tso(card, new_skb, 1)) { - if (skb_linearize(new_skb)) - goto tx_drop; - if (card->options.performance_stats) - card->perf_stats.tx_lin++; - } + 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)))) { + if (skb_linearize(new_skb)) + goto tx_drop; + if (card->options.performance_stats) + card->perf_stats.tx_lin++; } - if (large_send && (cast_type == RTN_UNSPEC)) { + if (use_tso) { hdr = (struct qeth_hdr *)skb_push(new_skb, sizeof(struct qeth_hdr_tso)); memset(hdr, 0, sizeof(struct qeth_hdr_tso)); @@ -2949,7 +2951,9 @@ static int qeth_l3_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) qeth_l3_hdr_csum(card, hdr, new_skb); } - elements = qeth_get_elements_no(card, new_skb, hdr_elements); + elements = use_tso ? + qeth_l3_get_elements_no_tso(card, new_skb, hdr_elements) : + qeth_get_elements_no(card, new_skb, hdr_elements); if (!elements) { if (data_offset >= 0) kmem_cache_free(qeth_core_header_cache, hdr); @@ -2959,7 +2963,7 @@ static int qeth_l3_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) if (card->info.type != QETH_CARD_TYPE_IQD) { int len; - if (large_send) + if (use_tso) len = ((unsigned long)tcp_hdr(new_skb) + tcp_hdrlen(new_skb)) - (unsigned long)new_skb->data; @@ -2980,7 +2984,7 @@ static int qeth_l3_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) dev_kfree_skb_any(skb); if (card->options.performance_stats) { nr_frags = skb_shinfo(new_skb)->nr_frags; - if (large_send) { + if (use_tso) { card->perf_stats.large_send_bytes += tx_bytes; card->perf_stats.large_send_cnt++; } -- 2.11.0