[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <14be343e242ede786e387b1d22f0a9259ec7d862.1320875577.git.david.decotigny@google.com>
Date: Wed, 9 Nov 2011 14:09:19 -0800
From: David Decotigny <david.decotigny@...gle.com>
To: netdev@...r.kernel.org, linux-kernel@...r.kernel.org
Cc: "David S. Miller" <davem@...emloft.net>,
Ian Campbell <ian.campbell@...rix.com>,
Eric Dumazet <eric.dumazet@...il.com>,
Jeff Kirsher <jeffrey.t.kirsher@...el.com>,
Ben Hutchings <bhutchings@...arflare.com>,
David Decotigny <david.decotigny@...gle.com>
Subject: [PATCH net-next v1 5/9] forcedeth: implement ndo_get_stats64() API
This commit implements the ndo_get_stats64() API for forcedeth. Since
these stats are being updated from different contexts (process and
timer), this commit adds protection (locking + atomic variables).
Tested:
16-way SMP x86_64 ->
RX bytes:7244556582 (7.2 GB) TX bytes:181904254 (181.9 MB)
Signed-off-by: David Decotigny <david.decotigny@...gle.com>
---
drivers/net/ethernet/nvidia/forcedeth.c | 132 +++++++++++++++++++++++--------
1 files changed, 99 insertions(+), 33 deletions(-)
diff --git a/drivers/net/ethernet/nvidia/forcedeth.c b/drivers/net/ethernet/nvidia/forcedeth.c
index 0071d5c..0b4fd1a 100644
--- a/drivers/net/ethernet/nvidia/forcedeth.c
+++ b/drivers/net/ethernet/nvidia/forcedeth.c
@@ -692,6 +692,19 @@ struct nv_ethtool_stats {
#define NV_DEV_STATISTICS_V2_COUNT (NV_DEV_STATISTICS_V3_COUNT - 3)
#define NV_DEV_STATISTICS_V1_COUNT (NV_DEV_STATISTICS_V2_COUNT - 6)
+/* driver statistics */
+struct nv_driver_stat {
+ atomic_t delta; /* increase since last nv_update_stats() */
+ u64 total; /* cumulative, requires netdev_priv(dev)->stats_lock */
+};
+
+#define NV_DRIVER_STAT_ATOMIC_INC(ptr_stat) /* atomic */ \
+ ({ atomic_inc(&(ptr_stat)->delta); })
+#define NV_DRIVER_STAT_UPDATE_TOTAL(ptr_stat) /* requires stats_lock */ \
+ ({ (ptr_stat)->total += atomic_xchg(&(ptr_stat)->delta, 0); })
+#define NV_DRIVER_STAT_GET_TOTAL(ptr_stat) /* requires stats_lock */ \
+ ((ptr_stat)->total)
+
/* diagnostics */
#define NV_TEST_COUNT_BASE 3
#define NV_TEST_COUNT_EXTENDED 4
@@ -736,6 +749,12 @@ struct nv_skb_map {
* - tx setup is lockless: it relies on netif_tx_lock. Actual submission
* needs netdev_priv(dev)->lock :-(
* - set_multicast_list: preparation lockless, relies on netif_tx_lock.
+ *
+ * Stats are protected with stats_lock:
+ * - updated by nv_do_stats_poll (timer). This is meant to avoid
+ * integer wraparound in the NIC stats registers, at low frequency
+ * (0.1 Hz)
+ * - updated by nv_get_ethtool_stats + nv_get_stats64
*/
/* in dev: base, irq */
@@ -745,9 +764,10 @@ struct fe_priv {
struct net_device *dev;
struct napi_struct napi;
- /* General data:
- * Locking: spin_lock(&np->lock); */
+ /* stats are updated in syscall and timer */
+ spinlock_t stats_lock;
struct nv_ethtool_stats estats;
+
int in_shutdown;
u32 linkspeed;
int duplex;
@@ -797,6 +817,7 @@ struct fe_priv {
struct timer_list stats_poll;
u32 nic_poll_irq;
int rx_ring_size;
+ struct nv_driver_stat stat_rx_missed_errors;
/* media detection workaround.
* Locking: Within irq hander or disable_irq+spin_lock(&np->lock);
@@ -819,6 +840,7 @@ struct fe_priv {
struct nv_skb_map *tx_change_owner;
struct nv_skb_map *tx_end_flip;
int tx_stop;
+ struct nv_driver_stat stat_tx_dropped;
/* msi/msi-x fields */
u32 msi_flags;
@@ -1635,11 +1657,19 @@ static void nv_mac_reset(struct net_device *dev)
pci_push(base);
}
-static void nv_get_hw_stats(struct net_device *dev)
+/* Caller must appropriately lock netdev_priv(dev)->stats_lock */
+static void nv_update_stats(struct net_device *dev)
{
struct fe_priv *np = netdev_priv(dev);
u8 __iomem *base = get_hwbase(dev);
+ /* If it happens that this is run in top-half context, then
+ * replace the spin_lock of stats_lock with
+ * spin_lock_irqsave() in calling functions. */
+ WARN_ONCE(in_irq(), "forcedeth: estats spin_lock(_bh) from top-half");
+ assert_spin_locked(&np->stats_lock);
+
+ /* query hardware */
np->estats.tx_bytes += readl(base + NvRegTxCnt);
np->estats.tx_zero_rexmt += readl(base + NvRegTxZeroReXmt);
np->estats.tx_one_rexmt += readl(base + NvRegTxOneReXmt);
@@ -1695,37 +1725,61 @@ static void nv_get_hw_stats(struct net_device *dev)
np->estats.tx_multicast += readl(base + NvRegTxMulticast);
np->estats.tx_broadcast += readl(base + NvRegTxBroadcast);
}
+
+ /* update software stats */
+ NV_DRIVER_STAT_UPDATE_TOTAL(&np->stat_tx_dropped);
+ NV_DRIVER_STAT_UPDATE_TOTAL(&np->stat_rx_missed_errors);
}
/*
- * nv_get_stats: dev->get_stats function
+ * nv_get_stats64: dev->ndo_get_stats64 function
* Get latest stats value from the nic.
* Called with read_lock(&dev_base_lock) held for read -
* only synchronized against unregister_netdevice.
*/
-static struct net_device_stats *nv_get_stats(struct net_device *dev)
+static struct rtnl_link_stats64*
+nv_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *storage)
+ __acquires(&netdev_priv(dev)->stats_lock)
+ __releases(&netdev_priv(dev)->stats_lock)
{
struct fe_priv *np = netdev_priv(dev);
/* If the nic supports hw counters then retrieve latest values */
- if (np->driver_data & (DEV_HAS_STATISTICS_V1|DEV_HAS_STATISTICS_V2|DEV_HAS_STATISTICS_V3)) {
- nv_get_hw_stats(dev);
-
- /* copy to net_device stats */
- dev->stats.rx_packets = np->estats.rx_packets;
- dev->stats.tx_packets = np->estats.tx_packets;
- dev->stats.rx_bytes = np->estats.rx_bytes;
- dev->stats.tx_bytes = np->estats.tx_bytes;
- dev->stats.tx_fifo_errors = np->estats.tx_fifo_errors;
- dev->stats.tx_carrier_errors = np->estats.tx_carrier_errors;
- dev->stats.rx_crc_errors = np->estats.rx_crc_errors;
- dev->stats.rx_over_errors = np->estats.rx_over_errors;
- dev->stats.rx_fifo_errors = np->estats.rx_drop_frame;
- dev->stats.rx_errors = np->estats.rx_errors_total;
- dev->stats.tx_errors = np->estats.tx_errors_total;
- }
-
- return &dev->stats;
+ if (np->driver_data & (DEV_HAS_STATISTICS_V1
+ | DEV_HAS_STATISTICS_V2
+ | DEV_HAS_STATISTICS_V3)) {
+ spin_lock_bh(&np->stats_lock);
+
+ nv_update_stats(dev);
+
+ /* generic stats */
+ storage->rx_packets = np->estats.rx_packets;
+ storage->tx_packets = np->estats.tx_packets;
+ storage->rx_bytes = np->estats.rx_bytes;
+ storage->tx_bytes = np->estats.tx_bytes;
+ storage->rx_errors = np->estats.rx_errors_total;
+ storage->tx_errors = np->estats.tx_errors_total;
+ storage->tx_dropped = NV_DRIVER_STAT_GET_TOTAL(
+ &np->stat_tx_dropped);
+ storage->multicast = np->estats.rx_multicast;
+
+ /* detailed rx_errors */
+ storage->rx_length_errors = np->estats.rx_length_error;
+ storage->rx_over_errors = np->estats.rx_over_errors;
+ storage->rx_crc_errors = np->estats.rx_crc_errors;
+ storage->rx_frame_errors = np->estats.rx_frame_align_error;
+ storage->rx_fifo_errors = np->estats.rx_drop_frame;
+ storage->rx_missed_errors = NV_DRIVER_STAT_GET_TOTAL(
+ &np->stat_rx_missed_errors);
+
+ /* detailed tx_errors */
+ storage->tx_carrier_errors = np->estats.tx_carrier_errors;
+ storage->tx_fifo_errors = np->estats.tx_fifo_errors;
+
+ spin_unlock_bh(&np->stats_lock);
+ }
+
+ return storage;
}
/*
@@ -1927,7 +1981,7 @@ static void nv_drain_tx(struct net_device *dev)
np->tx_ring.ex[i].buflow = 0;
}
if (nv_release_txskb(np, &np->tx_skb[i]))
- dev->stats.tx_dropped++;
+ NV_DRIVER_STAT_ATOMIC_INC(&np->stat_tx_dropped);
np->tx_skb[i].dma = 0;
np->tx_skb[i].dma_len = 0;
np->tx_skb[i].dma_single = 0;
@@ -2648,7 +2702,7 @@ static int nv_rx_process(struct net_device *dev, int limit)
/* the rest are hard errors */
else {
if (flags & NV_RX_MISSEDFRAME)
- dev->stats.rx_missed_errors++;
+ NV_DRIVER_STAT_ATOMIC_INC(&np->stat_rx_missed_errors);
dev_kfree_skb(skb);
goto next_pkt;
}
@@ -3900,11 +3954,18 @@ static void nv_poll_controller(struct net_device *dev)
#endif
static void nv_do_stats_poll(unsigned long data)
+ __acquires(&netdev_priv(dev)->stats_lock)
+ __releases(&netdev_priv(dev)->stats_lock)
{
struct net_device *dev = (struct net_device *) data;
struct fe_priv *np = netdev_priv(dev);
- nv_get_hw_stats(dev);
+ /* If lock is currently taken, the stats are being refreshed
+ * and hence fresh enough */
+ if (spin_trylock(&np->stats_lock)) {
+ nv_update_stats(dev);
+ spin_unlock(&np->stats_lock);
+ }
if (!np->in_shutdown)
mod_timer(&np->stats_poll,
@@ -4549,14 +4610,18 @@ static int nv_get_sset_count(struct net_device *dev, int sset)
}
}
-static void nv_get_ethtool_stats(struct net_device *dev, struct ethtool_stats *estats, u64 *buffer)
+static void nv_get_ethtool_stats(struct net_device *dev,
+ struct ethtool_stats *estats, u64 *buffer)
+ __acquires(&netdev_priv(dev)->stats_lock)
+ __releases(&netdev_priv(dev)->stats_lock)
{
struct fe_priv *np = netdev_priv(dev);
- /* update stats */
- nv_get_hw_stats(dev);
-
- memcpy(buffer, &np->estats, nv_get_sset_count(dev, ETH_SS_STATS)*sizeof(u64));
+ spin_lock_bh(&np->stats_lock);
+ nv_update_stats(dev);
+ memcpy(buffer, &np->estats,
+ nv_get_sset_count(dev, ETH_SS_STATS)*sizeof(u64));
+ spin_unlock_bh(&np->stats_lock);
}
static int nv_link_test(struct net_device *dev)
@@ -5194,7 +5259,7 @@ static int nv_close(struct net_device *dev)
static const struct net_device_ops nv_netdev_ops = {
.ndo_open = nv_open,
.ndo_stop = nv_close,
- .ndo_get_stats = nv_get_stats,
+ .ndo_get_stats64 = nv_get_stats64,
.ndo_start_xmit = nv_start_xmit,
.ndo_tx_timeout = nv_tx_timeout,
.ndo_change_mtu = nv_change_mtu,
@@ -5211,7 +5276,7 @@ static const struct net_device_ops nv_netdev_ops = {
static const struct net_device_ops nv_netdev_ops_optimized = {
.ndo_open = nv_open,
.ndo_stop = nv_close,
- .ndo_get_stats = nv_get_stats,
+ .ndo_get_stats64 = nv_get_stats64,
.ndo_start_xmit = nv_start_xmit_optimized,
.ndo_tx_timeout = nv_tx_timeout,
.ndo_change_mtu = nv_change_mtu,
@@ -5250,6 +5315,7 @@ static int __devinit nv_probe(struct pci_dev *pci_dev, const struct pci_device_i
np->dev = dev;
np->pci_dev = pci_dev;
spin_lock_init(&np->lock);
+ spin_lock_init(&np->stats_lock);
SET_NETDEV_DEV(dev, &pci_dev->dev);
init_timer(&np->oom_kick);
--
1.7.3.1
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists