qeth: introduce linearization fail count to stats

When skb data touches too many pages, skb_linearize() is called
opportunistically in the hope that less pages will be required
for a big linear buffer than for multiple fragments. This patch
intoduces a separate counter in ethtool statistics structure
representing _failed_ linearization attempts.

Signed-off-by: Eugene Crosser <Eugene.Crosser@ru.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Reviewed-by: Lakhvich Dmitriy <ldmitriy@ru.ibm.com>
Reviewed-by: Thomas Richter <tmricht@de.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 c3ab956..b4f14e4 100644 (file)
--- a/drivers/s390/net/qeth_core.h
+++ b/drivers/s390/net/qeth_core.h
@@ -145,6 +145,7 @@ struct qeth_perf_stats {
        unsigned int sg_alloc_page_rx;
        unsigned int tx_csum;
        unsigned int tx_lin;
+       unsigned int tx_linfail;
 };
 
 /* Routing stuff */

diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index a91a31d..9806ee0 100644 (file)
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -5801,6 +5801,7 @@ static struct {
        {"tx do_QDIO count"},
        {"tx csum"},
        {"tx lin"},
+       {"tx linfail"},
        {"cq handler count"},
        {"cq handler time"}
 };
@@ -5861,8 +5862,9 @@ void qeth_core_get_ethtool_stats(struct net_device *dev,
        data[32] = card->perf_stats.outbound_do_qdio_cnt;
        data[33] = card->perf_stats.tx_csum;
        data[34] = card->perf_stats.tx_lin;
-       data[35] = card->perf_stats.cq_cnt;
-       data[36] = card->perf_stats.cq_time;
+       data[35] = card->perf_stats.tx_linfail;
+       data[36] = card->perf_stats.cq_cnt;
+       data[37] = card->perf_stats.cq_time;
 }
 EXPORT_SYMBOL_GPL(qeth_core_get_ethtool_stats);
 

diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c
index e24627f..08b5fa9 100644 (file)
--- a/drivers/s390/net/qeth_l2_main.c
+++ b/drivers/s390/net/qeth_l2_main.c
@@ -898,10 +898,16 @@ static int qeth_l2_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
         */
        if ((card->info.type != QETH_CARD_TYPE_IQD) &&
            !qeth_get_elements_no(card, new_skb, 0)) {
-               if (skb_linearize(new_skb))
+               int lin_rc = skb_linearize(new_skb);
+
+               if (card->options.performance_stats) {
+                       if (lin_rc)
+                               card->perf_stats.tx_linfail++;
+                       else
+                               card->perf_stats.tx_lin++;
+               }
+               if (lin_rc)
                        goto tx_drop;
-               if (card->options.performance_stats)
-                       card->perf_stats.tx_lin++;
        }
 
        if (card->info.type == QETH_CARD_TYPE_OSN)

diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c
index 0afdb14..51077fb 100644 (file)
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -2918,10 +2918,16 @@ static int qeth_l3_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
        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))
+               int lin_rc = skb_linearize(new_skb);
+
+               if (card->options.performance_stats) {
+                       if (lin_rc)
+                               card->perf_stats.tx_linfail++;
+                       else
+                               card->perf_stats.tx_lin++;
+               }
+               if (lin_rc)
                        goto tx_drop;
-               if (card->options.performance_stats)
-                       card->perf_stats.tx_lin++;
        }
 
        if (use_tso) {