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authorBjørn Mork2014-05-16 21:48:25 +0200
committerDavid S. Miller2014-05-17 04:39:01 +0200
commitbeeecd42c3b41d17d0bf1d839db99274c287f514 (patch)
tree65bbae15a9ec1d3368a059f3bd4fad7d7c0a018b /drivers/net/usb/cdc_ncm.c
parentnet: cdc_ncm: set reasonable padding limits (diff)
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net: cdc_ncm/cdc_mbim: adding NCM protocol statistics
To have an idea of the effects of the protocol coalescing it's useful to have some counters showing the different aspects. Due to the asymmetrical usbnet interface the netdev rx_bytes counter has been counting real received payload, while the tx_bytes counter has included the NCM/MBIM framing overhead. This overhead can be many times the payload because of the aggressive padding strategy of this driver, and will vary a lot depending on device and traffic. With very few exceptions, users are only interested in the payload size. Having an somewhat accurate payload byte counter is particularly important for mobile broadband devices, which many NCM devices and of course all MBIM devices are. Users and userspace applications will use this counter to monitor account quotas. Having protocol specific counters for the overhead, we are now able to correct the tx_bytes netdev counter so that it shows the real payload Signed-off-by: Bjørn Mork <bjorn@mork.no> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/usb/cdc_ncm.c')
-rw-r--r--drivers/net/usb/cdc_ncm.c91
1 files changed, 91 insertions, 0 deletions
diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c
index 9592d4669435..f4b439847d04 100644
--- a/drivers/net/usb/cdc_ncm.c
+++ b/drivers/net/usb/cdc_ncm.c
@@ -65,6 +65,68 @@ static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx);
static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *hr_timer);
static struct usb_driver cdc_ncm_driver;
+struct cdc_ncm_stats {
+ char stat_string[ETH_GSTRING_LEN];
+ int sizeof_stat;
+ int stat_offset;
+};
+
+#define CDC_NCM_STAT(str, m) { \
+ .stat_string = str, \
+ .sizeof_stat = sizeof(((struct cdc_ncm_ctx *)0)->m), \
+ .stat_offset = offsetof(struct cdc_ncm_ctx, m) }
+#define CDC_NCM_SIMPLE_STAT(m) CDC_NCM_STAT(__stringify(m), m)
+
+static const struct cdc_ncm_stats cdc_ncm_gstrings_stats[] = {
+ CDC_NCM_SIMPLE_STAT(tx_reason_ntb_full),
+ CDC_NCM_SIMPLE_STAT(tx_reason_ndp_full),
+ CDC_NCM_SIMPLE_STAT(tx_reason_timeout),
+ CDC_NCM_SIMPLE_STAT(tx_reason_max_datagram),
+ CDC_NCM_SIMPLE_STAT(tx_overhead),
+ CDC_NCM_SIMPLE_STAT(tx_ntbs),
+ CDC_NCM_SIMPLE_STAT(rx_overhead),
+ CDC_NCM_SIMPLE_STAT(rx_ntbs),
+};
+
+static int cdc_ncm_get_sset_count(struct net_device __always_unused *netdev, int sset)
+{
+ switch (sset) {
+ case ETH_SS_STATS:
+ return ARRAY_SIZE(cdc_ncm_gstrings_stats);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static void cdc_ncm_get_ethtool_stats(struct net_device *netdev,
+ struct ethtool_stats __always_unused *stats,
+ u64 *data)
+{
+ struct usbnet *dev = netdev_priv(netdev);
+ struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
+ int i;
+ char *p = NULL;
+
+ for (i = 0; i < ARRAY_SIZE(cdc_ncm_gstrings_stats); i++) {
+ p = (char *)ctx + cdc_ncm_gstrings_stats[i].stat_offset;
+ data[i] = (cdc_ncm_gstrings_stats[i].sizeof_stat == sizeof(u64)) ? *(u64 *)p : *(u32 *)p;
+ }
+}
+
+static void cdc_ncm_get_strings(struct net_device __always_unused *netdev, u32 stringset, u8 *data)
+{
+ u8 *p = data;
+ int i;
+
+ switch (stringset) {
+ case ETH_SS_STATS:
+ for (i = 0; i < ARRAY_SIZE(cdc_ncm_gstrings_stats); i++) {
+ memcpy(p, cdc_ncm_gstrings_stats[i].stat_string, ETH_GSTRING_LEN);
+ p += ETH_GSTRING_LEN;
+ }
+ }
+}
+
static int cdc_ncm_get_coalesce(struct net_device *netdev,
struct ethtool_coalesce *ec)
{
@@ -122,6 +184,9 @@ static const struct ethtool_ops cdc_ncm_ethtool_ops = {
.get_msglevel = usbnet_get_msglevel,
.set_msglevel = usbnet_set_msglevel,
.get_ts_info = ethtool_op_get_ts_info,
+ .get_sset_count = cdc_ncm_get_sset_count,
+ .get_strings = cdc_ncm_get_strings,
+ .get_ethtool_stats = cdc_ncm_get_ethtool_stats,
.get_coalesce = cdc_ncm_get_coalesce,
.set_coalesce = cdc_ncm_set_coalesce,
};
@@ -862,6 +927,9 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign)
/* count total number of frames in this NTB */
ctx->tx_curr_frame_num = 0;
+
+ /* recent payload counter for this skb_out */
+ ctx->tx_curr_frame_payload = 0;
}
for (n = ctx->tx_curr_frame_num; n < ctx->tx_max_datagrams; n++) {
@@ -899,6 +967,7 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign)
ctx->tx_rem_sign = sign;
skb = NULL;
ready2send = 1;
+ ctx->tx_reason_ntb_full++; /* count reason for transmitting */
}
break;
}
@@ -912,12 +981,14 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign)
ndp16->dpe16[index].wDatagramIndex = cpu_to_le16(skb_out->len);
ndp16->wLength = cpu_to_le16(ndplen + sizeof(struct usb_cdc_ncm_dpe16));
memcpy(skb_put(skb_out, skb->len), skb->data, skb->len);
+ ctx->tx_curr_frame_payload += skb->len; /* count real tx payload data */
dev_kfree_skb_any(skb);
skb = NULL;
/* send now if this NDP is full */
if (index >= CDC_NCM_DPT_DATAGRAMS_MAX) {
ready2send = 1;
+ ctx->tx_reason_ndp_full++; /* count reason for transmitting */
break;
}
}
@@ -947,6 +1018,8 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign)
goto exit_no_skb;
} else {
+ if (n == ctx->tx_max_datagrams)
+ ctx->tx_reason_max_datagram++; /* count reason for transmitting */
/* frame goes out */
/* variables will be reset at next call */
}
@@ -974,6 +1047,17 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign)
/* return skb */
ctx->tx_curr_skb = NULL;
dev->net->stats.tx_packets += ctx->tx_curr_frame_num;
+
+ /* keep private stats: framing overhead and number of NTBs */
+ ctx->tx_overhead += skb_out->len - ctx->tx_curr_frame_payload;
+ ctx->tx_ntbs++;
+
+ /* usbnet has already counted all the framing overhead.
+ * Adjust the stats so that the tx_bytes counter show real
+ * payload data instead.
+ */
+ dev->net->stats.tx_bytes -= skb_out->len - ctx->tx_curr_frame_payload;
+
return skb_out;
exit_no_skb:
@@ -1014,6 +1098,7 @@ static void cdc_ncm_txpath_bh(unsigned long param)
cdc_ncm_tx_timeout_start(ctx);
spin_unlock_bh(&ctx->mtx);
} else if (dev->net != NULL) {
+ ctx->tx_reason_timeout++; /* count reason for transmitting */
spin_unlock_bh(&ctx->mtx);
netif_tx_lock_bh(dev->net);
usbnet_start_xmit(NULL, dev->net);
@@ -1149,6 +1234,7 @@ int cdc_ncm_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
struct usb_cdc_ncm_dpe16 *dpe16;
int ndpoffset;
int loopcount = 50; /* arbitrary max preventing infinite loop */
+ u32 payload = 0;
ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in);
if (ndpoffset < 0)
@@ -1201,6 +1287,7 @@ next_ndp:
skb->data = ((u8 *)skb_in->data) + offset;
skb_set_tail_pointer(skb, len);
usbnet_skb_return(dev, skb);
+ payload += len; /* count payload bytes in this NTB */
}
}
err_ndp:
@@ -1209,6 +1296,10 @@ err_ndp:
if (ndpoffset && loopcount--)
goto next_ndp;
+ /* update stats */
+ ctx->rx_overhead += skb_in->len - payload;
+ ctx->rx_ntbs++;
+
return 1;
error:
return 0;