s390/qeth: add statistics for consumed buffer elements

Nowadays an skb fragment typically spans over multiple pages. So replace
the obsolete, SG-only 'fragments' counter with one that tracks the
consumed buffer elements. This is what actually matters for performance.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h
index 994ac7f..6d8005a 100644 (file)
--- a/drivers/s390/net/qeth_core.h
+++ b/drivers/s390/net/qeth_core.h
@@ -104,6 +104,7 @@ struct qeth_dbf_info {
 struct qeth_perf_stats {
        unsigned int bufs_rec;
        unsigned int bufs_sent;
+       unsigned int buf_elements_sent;
 
        unsigned int skbs_sent_pack;
        unsigned int bufs_sent_pack;
@@ -137,7 +138,6 @@ struct qeth_perf_stats {
        unsigned int large_send_bytes;
        unsigned int large_send_cnt;
        unsigned int sg_skbs_sent;
-       unsigned int sg_frags_sent;
        /* initial values when measuring starts */
        unsigned long initial_rx_packets;
        unsigned long initial_tx_packets;

diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index 717511c..84f1e1e 100644 (file)
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -5970,7 +5970,7 @@ static struct {
        {"tx skbs packing"},
        {"tx buffers packing"},
        {"tx sg skbs"},
-       {"tx sg frags"},
+       {"tx buffer elements"},
 /* 10 */{"rx sg skbs"},
        {"rx sg frags"},
        {"rx sg page allocs"},
@@ -6029,7 +6029,7 @@ void qeth_core_get_ethtool_stats(struct net_device *dev,
        data[6] = card->perf_stats.skbs_sent_pack;
        data[7] = card->perf_stats.bufs_sent_pack;
        data[8] = card->perf_stats.sg_skbs_sent;
-       data[9] = card->perf_stats.sg_frags_sent;
+       data[9] = card->perf_stats.buf_elements_sent;
        data[10] = card->perf_stats.sg_skbs_rx;
        data[11] = card->perf_stats.sg_frags_rx;
        data[12] = card->perf_stats.sg_alloc_page_rx;

diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c
index 668f806..a785c5f 100644 (file)
--- a/drivers/s390/net/qeth_l2_main.c
+++ b/drivers/s390/net/qeth_l2_main.c
@@ -672,10 +672,11 @@ static int qeth_l2_xmit_osa(struct qeth_card *card, struct sk_buff *skb,
                            int ipv)
 {
        int push_len = sizeof(struct qeth_hdr);
-       unsigned int elements, nr_frags;
        unsigned int hdr_elements = 0;
        struct qeth_hdr *hdr = NULL;
        unsigned int hd_len = 0;
+       unsigned int elements;
+       bool is_sg;
        int rc;
 
        /* fix hardware limitation: as long as we do not have sbal
@@ -693,7 +694,6 @@ static int qeth_l2_xmit_osa(struct qeth_card *card, struct sk_buff *skb,
                if (rc)
                        return rc;
        }
-       nr_frags = skb_shinfo(skb)->nr_frags;
 
        rc = skb_cow_head(skb, push_len);
        if (rc)
@@ -720,15 +720,16 @@ static int qeth_l2_xmit_osa(struct qeth_card *card, struct sk_buff *skb,
        }
        elements += hdr_elements;
 
+       is_sg = skb_is_nonlinear(skb);
        /* TODO: remove the skb_orphan() once TX completion is fast enough */
        skb_orphan(skb);
        rc = qeth_do_send_packet(card, queue, skb, hdr, 0, hd_len, elements);
 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;
+               if (card->options.performance_stats) {
+                       card->perf_stats.buf_elements_sent += elements;
+                       if (is_sg)
+                               card->perf_stats.sg_skbs_sent++;
                }
        } else {
                if (hd_len)

diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c
index 078b891..c12aeb7 100644 (file)
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -2166,12 +2166,13 @@ static int qeth_l3_xmit_offload(struct qeth_card *card, struct sk_buff *skb,
                                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;
        int elements, push_len, rc;
        unsigned int hd_len = 0;
+       unsigned int frame_len;
+       bool is_sg;
 
        /* compress skb to fit into one IO buffer: */
        if (!qeth_get_elements_no(card, skb, 0, 0)) {
@@ -2194,7 +2195,6 @@ static int qeth_l3_xmit_offload(struct qeth_card *card, struct sk_buff *skb,
        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)
@@ -2217,6 +2217,7 @@ static int qeth_l3_xmit_offload(struct qeth_card *card, struct sk_buff *skb,
        else
                qeth_l3_fill_header(card, hdr, skb, ipv, cast_type, frame_len);
 
+       is_sg = skb_is_nonlinear(skb);
        if (IS_IQD(card)) {
                rc = qeth_do_send_packet_fast(queue, skb, hdr, 0, hd_len);
        } else {
@@ -2227,10 +2228,10 @@ static int qeth_l3_xmit_offload(struct qeth_card *card, struct sk_buff *skb,
        }
 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;
+               if (card->options.performance_stats) {
+                       card->perf_stats.buf_elements_sent += elements;
+                       if (is_sg)
+                               card->perf_stats.sg_skbs_sent++;
                }
        } else {
                if (!push_len)
@@ -2248,14 +2249,14 @@ out:
 static int qeth_l3_xmit(struct qeth_card *card, struct sk_buff *skb,
                        struct qeth_qdio_out_q *queue, int ipv, int cast_type)
 {
-       unsigned int hd_len, nr_frags;
        int elements, len, rc;
        __be16 *tag;
        struct qeth_hdr *hdr = NULL;
        int hdr_elements = 0;
        struct sk_buff *new_skb = NULL;
        int tx_bytes = skb->len;
-       bool use_tso;
+       unsigned int hd_len;
+       bool use_tso, is_sg;
 
        /* Ignore segment size from skb_is_gso(), 1 page is always used. */
        use_tso = skb_is_gso(skb) &&
@@ -2297,7 +2298,6 @@ static int qeth_l3_xmit(struct qeth_card *card, struct sk_buff *skb,
                if (rc)
                        goto out;
        }
-       nr_frags = skb_shinfo(new_skb)->nr_frags;
 
        if (use_tso) {
                hdr = skb_push(new_skb, sizeof(struct qeth_hdr_tso));
@@ -2334,6 +2334,8 @@ static int qeth_l3_xmit(struct qeth_card *card, struct sk_buff *skb,
                rc = -EINVAL;
                goto out;
        }
+
+       is_sg = skb_is_nonlinear(new_skb);
        rc = qeth_do_send_packet(card, queue, new_skb, hdr, hd_len, hd_len,
                                 elements);
 out:
@@ -2341,15 +2343,13 @@ out:
                if (new_skb != skb)
                        dev_kfree_skb_any(skb);
                if (card->options.performance_stats) {
+                       card->perf_stats.buf_elements_sent += elements;
+                       if (is_sg)
+                               card->perf_stats.sg_skbs_sent++;
                        if (use_tso) {
                                card->perf_stats.large_send_bytes += tx_bytes;
                                card->perf_stats.large_send_cnt++;
                        }
-                       if (nr_frags) {
-                               card->perf_stats.sg_skbs_sent++;
-                               /* nr_frags + skb->data */
-                               card->perf_stats.sg_frags_sent += nr_frags + 1;
-                       }
                }
        } else {
                if (new_skb != skb)