| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <6c785722f068deef5ff546f53b8011ecff43a4c1.1321384662.git.david.decotigny@google.com>
Date: Tue, 15 Nov 2011 11:25:38 -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>,
Jiri Pirko <jpirko@...hat.com>, Joe Perches <joe@...ches.com>,
Szymon Janc <szymon@...c.net.pl>,
Richard Jones <rick.jones2@...com>,
Ayaz Abdulla <AAbdulla@...dia.com>,
David Decotigny <david.decotigny@...gle.com>
Subject: [PATCH net-next v4 5/8] forcedeth: implement ndo_get_stats64() API
This commit implements the ndo_get_stats64() API for forcedeth. Since
hardware stats are being updated from different contexts (process and
timer), this commit adds protection (locking + atomic variables). For
software stats, it relies on the u64_stats_sync.h API.
Tested:
- 16-way SMP x86_64 ->
RX bytes:7244556582 (7.2 GB) TX bytes:181904254 (181.9 MB)
- pktgen + loopback: identical rx_bytes/tx_bytes and rx_packets/tx_packets
Signed-off-by: David Decotigny <david.decotigny@...gle.com>
---
drivers/net/ethernet/nvidia/forcedeth.c | 195 +++++++++++++++++++++++--------
1 files changed, 144 insertions(+), 51 deletions(-)
diff --git a/drivers/net/ethernet/nvidia/forcedeth.c b/drivers/net/ethernet/nvidia/forcedeth.c
index ee8cce5..ff01d5e 100644
--- a/drivers/net/ethernet/nvidia/forcedeth.c
+++ b/drivers/net/ethernet/nvidia/forcedeth.c
@@ -65,7 +65,8 @@
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/prefetch.h>
-#include <linux/io.h>
+#include <linux/u64_stats_sync.h>
+#include <linux/io.h>
#include <asm/irq.h>
#include <asm/system.h>
@@ -736,6 +737,18 @@ 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.
+ *
+ * Hardware stats updates are protected by hwstats_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
+ *
+ * Software stats are accessed only through a 64b synchronization
+ * point and are not subject to other synchronization techniques (one
+ * unique updating thread for each stat [single queue RX/TX fast
+ * paths], or callers already synchronized [for tx_dropped, except from
+ * nv_open/nv_close]).
*/
/* in dev: base, irq */
@@ -745,9 +758,13 @@ struct fe_priv {
struct net_device *dev;
struct napi_struct napi;
- /* General data:
- * Locking: spin_lock(&np->lock); */
+ /* hardware stats are updated in syscall and timer */
+ spinlock_t hwstats_lock;
struct nv_ethtool_stats estats;
+
+ /* software stats are accessed through a 64b synchronization point */
+ struct u64_stats_sync swstats_syncp;
+
int in_shutdown;
u32 linkspeed;
int duplex;
@@ -798,6 +815,11 @@ struct fe_priv {
u32 nic_poll_irq;
int rx_ring_size;
+ /* RX software stats */
+ u64 stat_rx_packets;
+ u64 stat_rx_bytes; /* not always available in HW */
+ u64 stat_rx_missed_errors;
+
/* media detection workaround.
* Locking: Within irq hander or disable_irq+spin_lock(&np->lock);
*/
@@ -820,6 +842,11 @@ struct fe_priv {
struct nv_skb_map *tx_end_flip;
int tx_stop;
+ /* TX software stats */
+ u64 stat_tx_packets; /* not always available in HW */
+ u64 stat_tx_bytes;
+ u64 stat_tx_dropped;
+
/* msi/msi-x fields */
u32 msi_flags;
struct msix_entry msi_x_entry[NV_MSI_X_MAX_VECTORS];
@@ -1635,11 +1662,19 @@ 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)->hwstats_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 hwstats_lock with
+ * spin_lock_irqsave() in calling functions. */
+ WARN_ONCE(in_irq(), "forcedeth: estats spin_lock(_bh) from top-half");
+ assert_spin_locked(&np->hwstats_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);
@@ -1698,40 +1733,67 @@ static void nv_get_hw_stats(struct net_device *dev)
}
/*
- * 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)->hwstats_lock)
+ __releases(&netdev_priv(dev)->hwstats_lock)
{
struct fe_priv *np = netdev_priv(dev);
+ unsigned int syncp_start;
+
+ /*
+ * Note: because HW stats are not always available and for
+ * consistency reasons, the following ifconfig stats are
+ * managed by software: rx_bytes, tx_bytes, rx_packets and
+ * tx_packets. The related hardware stats reported by ethtool
+ * should be equivalent to these ifconfig stats, with 4
+ * additional bytes per packet (Ethernet FCS CRC).
+ */
+
+ /* software stats */
+ do {
+ syncp_start = u64_stats_fetch_begin(&np->swstats_syncp);
+ storage->rx_packets = np->stat_rx_packets;
+ storage->tx_packets = np->stat_tx_packets;
+ storage->rx_bytes = np->stat_rx_bytes;
+ storage->tx_bytes = np->stat_tx_bytes;
+ storage->tx_dropped = np->stat_tx_dropped;
+ storage->rx_missed_errors = np->stat_rx_missed_errors;
+ } while (u64_stats_fetch_retry(&np->swstats_syncp, syncp_start));
/* 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);
+ if (np->driver_data & DEV_HAS_STATISTICS_V123) {
+ spin_lock_bh(&np->hwstats_lock);
- /*
- * Note: because HW stats are not always available and
- * for consistency reasons, the following ifconfig
- * stats are managed by software: rx_bytes, tx_bytes,
- * rx_packets and tx_packets. The related hardware
- * stats reported by ethtool should be equivalent to
- * these ifconfig stats, with 4 additional bytes per
- * packet (Ethernet FCS CRC).
- */
+ nv_update_stats(dev);
+
+ /* generic stats */
+ storage->rx_errors = np->estats.rx_errors_total;
+ storage->tx_errors = np->estats.tx_errors_total;
+
+ /* meaningful only when NIC supports stats v3 */
+ 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;
- /* copy to net_device stats */
- 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;
+ /* 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->hwstats_lock);
}
- return &dev->stats;
+ return storage;
}
/*
@@ -1932,8 +1994,11 @@ static void nv_drain_tx(struct net_device *dev)
np->tx_ring.ex[i].bufhigh = 0;
np->tx_ring.ex[i].buflow = 0;
}
- if (nv_release_txskb(np, &np->tx_skb[i]))
- dev->stats.tx_dropped++;
+ if (nv_release_txskb(np, &np->tx_skb[i])) {
+ u64_stats_update_begin(&np->swstats_syncp);
+ np->stat_tx_dropped++;
+ u64_stats_update_end(&np->swstats_syncp);
+ }
np->tx_skb[i].dma = 0;
np->tx_skb[i].dma_len = 0;
np->tx_skb[i].dma_single = 0;
@@ -2390,11 +2455,14 @@ static int nv_tx_done(struct net_device *dev, int limit)
if (np->desc_ver == DESC_VER_1) {
if (flags & NV_TX_LASTPACKET) {
if (flags & NV_TX_ERROR) {
- if ((flags & NV_TX_RETRYERROR) && !(flags & NV_TX_RETRYCOUNT_MASK))
+ if ((flags & NV_TX_RETRYERROR)
+ && !(flags & NV_TX_RETRYCOUNT_MASK))
nv_legacybackoff_reseed(dev);
} else {
- dev->stats.tx_packets++;
- dev->stats.tx_bytes += np->get_tx_ctx->skb->len;
+ u64_stats_update_begin(&np->swstats_syncp);
+ np->stat_tx_packets++;
+ np->stat_tx_bytes += np->get_tx_ctx->skb->len;
+ u64_stats_update_end(&np->swstats_syncp);
}
dev_kfree_skb_any(np->get_tx_ctx->skb);
np->get_tx_ctx->skb = NULL;
@@ -2403,11 +2471,14 @@ static int nv_tx_done(struct net_device *dev, int limit)
} else {
if (flags & NV_TX2_LASTPACKET) {
if (flags & NV_TX2_ERROR) {
- if ((flags & NV_TX2_RETRYERROR) && !(flags & NV_TX2_RETRYCOUNT_MASK))
+ if ((flags & NV_TX2_RETRYERROR)
+ && !(flags & NV_TX2_RETRYCOUNT_MASK))
nv_legacybackoff_reseed(dev);
} else {
- dev->stats.tx_packets++;
- dev->stats.tx_bytes += np->get_tx_ctx->skb->len;
+ u64_stats_update_begin(&np->swstats_syncp);
+ np->stat_tx_packets++;
+ np->stat_tx_bytes += np->get_tx_ctx->skb->len;
+ u64_stats_update_end(&np->swstats_syncp);
}
dev_kfree_skb_any(np->get_tx_ctx->skb);
np->get_tx_ctx->skb = NULL;
@@ -2441,15 +2512,18 @@ static int nv_tx_done_optimized(struct net_device *dev, int limit)
if (flags & NV_TX2_LASTPACKET) {
if (flags & NV_TX2_ERROR) {
- if ((flags & NV_TX2_RETRYERROR) && !(flags & NV_TX2_RETRYCOUNT_MASK)) {
+ if ((flags & NV_TX2_RETRYERROR)
+ && !(flags & NV_TX2_RETRYCOUNT_MASK)) {
if (np->driver_data & DEV_HAS_GEAR_MODE)
nv_gear_backoff_reseed(dev);
else
nv_legacybackoff_reseed(dev);
}
} else {
- dev->stats.tx_packets++;
- dev->stats.tx_bytes += np->get_tx_ctx->skb->len;
+ u64_stats_update_begin(&np->swstats_syncp);
+ np->stat_tx_packets++;
+ np->stat_tx_bytes += np->get_tx_ctx->skb->len;
+ u64_stats_update_end(&np->swstats_syncp);
}
dev_kfree_skb_any(np->get_tx_ctx->skb);
@@ -2662,8 +2736,11 @@ 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++;
+ if (flags & NV_RX_MISSEDFRAME) {
+ u64_stats_update_begin(&np->swstats_syncp);
+ np->stat_rx_missed_errors++;
+ u64_stats_update_end(&np->swstats_syncp);
+ }
dev_kfree_skb(skb);
goto next_pkt;
}
@@ -2706,8 +2783,10 @@ static int nv_rx_process(struct net_device *dev, int limit)
skb_put(skb, len);
skb->protocol = eth_type_trans(skb, dev);
napi_gro_receive(&np->napi, skb);
- dev->stats.rx_packets++;
- dev->stats.rx_bytes += len;
+ u64_stats_update_begin(&np->swstats_syncp);
+ np->stat_rx_packets++;
+ np->stat_rx_bytes += len;
+ u64_stats_update_end(&np->swstats_syncp);
next_pkt:
if (unlikely(np->get_rx.orig++ == np->last_rx.orig))
np->get_rx.orig = np->first_rx.orig;
@@ -2790,8 +2869,10 @@ static int nv_rx_process_optimized(struct net_device *dev, int limit)
__vlan_hwaccel_put_tag(skb, vid);
}
napi_gro_receive(&np->napi, skb);
- dev->stats.rx_packets++;
- dev->stats.rx_bytes += len;
+ u64_stats_update_begin(&np->swstats_syncp);
+ np->stat_rx_packets++;
+ np->stat_rx_bytes += len;
+ u64_stats_update_end(&np->swstats_syncp);
} else {
dev_kfree_skb(skb);
}
@@ -4000,11 +4081,18 @@ static void nv_poll_controller(struct net_device *dev)
#endif
static void nv_do_stats_poll(unsigned long data)
+ __acquires(&netdev_priv(dev)->hwstats_lock)
+ __releases(&netdev_priv(dev)->hwstats_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->hwstats_lock)) {
+ nv_update_stats(dev);
+ spin_unlock(&np->hwstats_lock);
+ }
if (!np->in_shutdown)
mod_timer(&np->stats_poll,
@@ -4711,14 +4799,18 @@ 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)->hwstats_lock)
+ __releases(&netdev_priv(dev)->hwstats_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->hwstats_lock);
+ nv_update_stats(dev);
+ memcpy(buffer, &np->estats,
+ nv_get_sset_count(dev, ETH_SS_STATS)*sizeof(u64));
+ spin_unlock_bh(&np->hwstats_lock);
}
static int nv_link_test(struct net_device *dev)
@@ -5362,7 +5454,7 @@ 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,
@@ -5379,7 +5471,7 @@ 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,
@@ -5418,6 +5510,7 @@ 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->hwstats_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 linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists