net: Explicitly initialize u64_stats_sync structures for lockdep

In order to enable lockdep on seqcount/seqlock structures, we
must explicitly initialize any locks.

The u64_stats_sync structure, uses a seqcount, and thus we need
to introduce a u64_stats_init() function and use it to initialize
the structure.

This unfortunately adds a lot of fairly trivial initialization code
to a number of drivers. But the benefit of ensuring correctness makes
this worth while.

Because these changes are required for lockdep to be enabled, and the
changes are quite trivial, I've not yet split this patch out into 30-some
separate patches, as I figured it would be better to get the various
maintainers thoughts on how to best merge this change along with
the seqcount lockdep enablement.

Feedback would be appreciated!

Signed-off-by: John Stultz <john.stultz@linaro.org>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: James Morris <jmorris@namei.org>
Cc: Jesse Gross <jesse@nicira.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Mirko Lindner <mlindner@marvell.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Roger Luethi <rl@hellgate.ch>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Simon Horman <horms@verge.net.au>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Wensong Zhang <wensong@linux-vs.org>
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/1381186321-4906-2-git-send-email-john.stultz@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

21 files changed, 109 insertions, 1 deletions

diff --git a/drivers/net/dummy.c b/drivers/net/dummy.c
index b710c6b2d659..bd8f84b0b894 100644
--- a/drivers/net/dummy.c
+++ b/drivers/net/dummy.c
@@ -88,10 +88,16 @@ static netdev_tx_t dummy_xmit(struct sk_buff *skb, struct net_device *dev)
 
 static int dummy_dev_init(struct net_device *dev)
 {
+        int i;
         dev->dstats = alloc_percpu(struct pcpu_dstats);
         if (!dev->dstats)
                 return -ENOMEM;
 
+        for_each_possible_cpu(i) {
+                struct pcpu_dstats *dstats;
+                dstats = per_cpu_ptr(dev->dstats, i);
+                u64_stats_init(&dstats->syncp);
+        }
         return 0;
 }
 
diff --git a/drivers/net/ethernet/emulex/benet/be_main.c b/drivers/net/ethernet/emulex/benet/be_main.c
index 2c38cc402119..edd75950855a 100644
--- a/drivers/net/ethernet/emulex/benet/be_main.c
+++ b/drivers/net/ethernet/emulex/benet/be_main.c
@@ -2047,6 +2047,9 @@ static int be_tx_qs_create(struct be_adapter *adapter)
                 if (status)
                         return status;
 
+                u64_stats_init(&txo->stats.sync);
+                u64_stats_init(&txo->stats.sync_compl);
+
                 /* If num_evt_qs is less than num_tx_qs, then more than
                  * one txq share an eq
                  */
@@ -2108,6 +2111,7 @@ static int be_rx_cqs_create(struct be_adapter *adapter)
                 if (rc)
                         return rc;
 
+                u64_stats_init(&rxo->stats.sync);
                 eq = &adapter->eq_obj[i % adapter->num_evt_qs].q;
                 rc = be_cmd_cq_create(adapter, cq, eq, false, 3);
                 if (rc)
diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c
index 8cf44f2a8ccd..b6edb93a8fc1 100644
--- a/drivers/net/ethernet/intel/igb/igb_main.c
+++ b/drivers/net/ethernet/intel/igb/igb_main.c
@@ -1223,6 +1223,9 @@ static int igb_alloc_q_vector(struct igb_adapter *adapter,
                 ring->count = adapter->tx_ring_count;
                 ring->queue_index = txr_idx;
 
+                u64_stats_init(&ring->tx_syncp);
+                u64_stats_init(&ring->tx_syncp2);
+
                 /* assign ring to adapter */
                 adapter->tx_ring[txr_idx] = ring;
 
@@ -1256,6 +1259,8 @@ static int igb_alloc_q_vector(struct igb_adapter *adapter,
                 ring->count = adapter->rx_ring_count;
                 ring->queue_index = rxr_idx;
 
+                u64_stats_init(&ring->rx_syncp);
+
                 /* assign ring to adapter */
                 adapter->rx_ring[rxr_idx] = ring;
         }
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 0ade0cd5ef53..c1750364ddc0 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -4867,6 +4867,8 @@ int ixgbe_setup_tx_resources(struct ixgbe_ring *tx_ring)
         if (!tx_ring->tx_buffer_info)
                 goto err;
 
+        u64_stats_init(&tx_ring->syncp);
+
         /* round up to nearest 4K */
         tx_ring->size = tx_ring->count * sizeof(union ixgbe_adv_tx_desc);
         tx_ring->size = ALIGN(tx_ring->size, 4096);
@@ -4949,6 +4951,8 @@ int ixgbe_setup_rx_resources(struct ixgbe_ring *rx_ring)
         if (!rx_ring->rx_buffer_info)
                 goto err;
 
+        u64_stats_init(&rx_ring->syncp);
+
         /* Round up to nearest 4K */
         rx_ring->size = rx_ring->count * sizeof(union ixgbe_adv_rx_desc);
         rx_ring->size = ALIGN(rx_ring->size, 4096);
diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
index e35bac7cfdf1..cb4635c0cd73 100644
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c
@@ -2792,6 +2792,9 @@ static int mvneta_probe(struct platform_device *pdev)
 
         pp = netdev_priv(dev);
 
+        u64_stats_init(&pp->tx_stats.syncp);
+        u64_stats_init(&pp->rx_stats.syncp);
+
         pp->weight = MVNETA_RX_POLL_WEIGHT;
         pp->phy_node = phy_node;
         pp->phy_interface = phy_mode;
diff --git a/drivers/net/ethernet/marvell/sky2.c b/drivers/net/ethernet/marvell/sky2.c
index e09a8c6f8536..339d841a538b 100644
--- a/drivers/net/ethernet/marvell/sky2.c
+++ b/drivers/net/ethernet/marvell/sky2.c
@@ -4763,6 +4763,9 @@ static struct net_device *sky2_init_netdev(struct sky2_hw *hw, unsigned port,
         sky2->hw = hw;
         sky2->msg_enable = netif_msg_init(debug, default_msg);
 
+        u64_stats_init(&sky2->tx_stats.syncp);
+        u64_stats_init(&sky2->rx_stats.syncp);
+
         /* Auto speed and flow control */
         sky2->flags = SKY2_FLAG_AUTO_SPEED | SKY2_FLAG_AUTO_PAUSE;
         if (hw->chip_id != CHIP_ID_YUKON_XL)
diff --git a/drivers/net/ethernet/neterion/vxge/vxge-main.c b/drivers/net/ethernet/neterion/vxge/vxge-main.c
index 5a20eaf903dd..44626ec1127b 100644
--- a/drivers/net/ethernet/neterion/vxge/vxge-main.c
+++ b/drivers/net/ethernet/neterion/vxge/vxge-main.c
@@ -2072,6 +2072,10 @@ static int vxge_open_vpaths(struct vxgedev *vdev)
                                 vdev->config.tx_steering_type;
                         vpath->fifo.ndev = vdev->ndev;
                         vpath->fifo.pdev = vdev->pdev;
+
+                        u64_stats_init(&vpath->fifo.stats.syncp);
+                        u64_stats_init(&vpath->ring.stats.syncp);
+
                         if (vdev->config.tx_steering_type)
                                 vpath->fifo.txq =
                                         netdev_get_tx_queue(vdev->ndev, i);
diff --git a/drivers/net/ethernet/nvidia/forcedeth.c b/drivers/net/ethernet/nvidia/forcedeth.c
index 098b96dad66f..2d045be4b5cf 100644
--- a/drivers/net/ethernet/nvidia/forcedeth.c
+++ b/drivers/net/ethernet/nvidia/forcedeth.c
@@ -5619,6 +5619,8 @@ static int nv_probe(struct pci_dev *pci_dev, const struct pci_device_id *id)
         spin_lock_init(&np->lock);
         spin_lock_init(&np->hwstats_lock);
         SET_NETDEV_DEV(dev, &pci_dev->dev);
+        u64_stats_init(&np->swstats_rx_syncp);
+        u64_stats_init(&np->swstats_tx_syncp);
 
         init_timer(&np->oom_kick);
         np->oom_kick.data = (unsigned long) dev;
diff --git a/drivers/net/ethernet/realtek/8139too.c b/drivers/net/ethernet/realtek/8139too.c
index 3ccedeb8aba0..c40e984868ad 100644
--- a/drivers/net/ethernet/realtek/8139too.c
+++ b/drivers/net/ethernet/realtek/8139too.c
@@ -791,6 +791,9 @@ static struct net_device *rtl8139_init_board(struct pci_dev *pdev)
 
         pci_set_master (pdev);
 
+        u64_stats_init(&tp->rx_stats.syncp);
+        u64_stats_init(&tp->tx_stats.syncp);
+
 retry:
         /* PIO bar register comes first. */
         bar = !use_io;
diff --git a/drivers/net/ethernet/tile/tilepro.c b/drivers/net/ethernet/tile/tilepro.c
index 106be47716e7..edb2e12a0fe2 100644
--- a/drivers/net/ethernet/tile/tilepro.c
+++ b/drivers/net/ethernet/tile/tilepro.c
@@ -1008,6 +1008,8 @@ static void tile_net_register(void *dev_ptr)
         info->egress_timer.data = (long)info;
         info->egress_timer.function = tile_net_handle_egress_timer;
 
+        u64_stats_init(&info->stats.syncp);
+
         priv->cpu[my_cpu] = info;
 
         /*
diff --git a/drivers/net/ethernet/via/via-rhine.c b/drivers/net/ethernet/via/via-rhine.c
index bdf697b184ae..dd99715e6645 100644
--- a/drivers/net/ethernet/via/via-rhine.c
+++ b/drivers/net/ethernet/via/via-rhine.c
@@ -987,6 +987,9 @@ static int rhine_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 
         rp->base = ioaddr;
 
+        u64_stats_init(&rp->tx_stats.syncp);
+        u64_stats_init(&rp->rx_stats.syncp);
+
         /* Get chip registers into a sane state */
         rhine_power_init(dev);
         rhine_hw_init(dev, pioaddr);
diff --git a/drivers/net/ifb.c b/drivers/net/ifb.c
index a3bed28197d2..c14d39bf32d0 100644
--- a/drivers/net/ifb.c
+++ b/drivers/net/ifb.c
@@ -265,6 +265,7 @@ MODULE_PARM_DESC(numifbs, "Number of ifb devices");
 static int __init ifb_init_one(int index)
 {
         struct net_device *dev_ifb;
+        struct ifb_private *dp;
         int err;
 
         dev_ifb = alloc_netdev(sizeof(struct ifb_private),
@@ -273,6 +274,10 @@ static int __init ifb_init_one(int index)
         if (!dev_ifb)
                 return -ENOMEM;
 
+        dp = netdev_priv(dev_ifb);
+        u64_stats_init(&dp->rsync);
+        u64_stats_init(&dp->tsync);
+
         dev_ifb->rtnl_link_ops = &ifb_link_ops;
         err = register_netdevice(dev_ifb);
         if (err < 0)
diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c
index a17d85a331f1..ac24c27b4b2d 100644
--- a/drivers/net/loopback.c
+++ b/drivers/net/loopback.c
@@ -137,10 +137,16 @@ static const struct ethtool_ops loopback_ethtool_ops = {
 
 static int loopback_dev_init(struct net_device *dev)
 {
+        int i;
         dev->lstats = alloc_percpu(struct pcpu_lstats);
         if (!dev->lstats)
                 return -ENOMEM;
 
+        for_each_possible_cpu(i) {
+                struct pcpu_lstats *lb_stats;
+                lb_stats = per_cpu_ptr(dev->lstats, i);
+                u64_stats_init(&lb_stats->syncp);
+        }
         return 0;
 }
 
diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index 9bf46bd19b87..0924e51b9ee0 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -501,6 +501,7 @@ static int macvlan_init(struct net_device *dev)
 {
         struct macvlan_dev *vlan = netdev_priv(dev);
         const struct net_device *lowerdev = vlan->lowerdev;
+        int i;
 
         dev->state              = (dev->state & ~MACVLAN_STATE_MASK) |
                                   (lowerdev->state & MACVLAN_STATE_MASK);
@@ -516,6 +517,12 @@ static int macvlan_init(struct net_device *dev)
         if (!vlan->pcpu_stats)
                 return -ENOMEM;
 
+        for_each_possible_cpu(i) {
+                struct macvlan_pcpu_stats *mvlstats;
+                mvlstats = per_cpu_ptr(vlan->pcpu_stats, i);
+                u64_stats_init(&mvlstats->syncp);
+        }
+
         return 0;
 }
 
diff --git a/drivers/net/nlmon.c b/drivers/net/nlmon.c
index b57ce5f48962..d2bb12bfabd5 100644
--- a/drivers/net/nlmon.c
+++ b/drivers/net/nlmon.c
@@ -47,8 +47,16 @@ static int nlmon_change_mtu(struct net_device *dev, int new_mtu)
 
 static int nlmon_dev_init(struct net_device *dev)
 {
+        int i;
+
         dev->lstats = alloc_percpu(struct pcpu_lstats);
 
+        for_each_possible_cpu(i) {
+                struct pcpu_lstats *nlmstats;
+                nlmstats = per_cpu_ptr(dev->lstats, i);
+                u64_stats_init(&nlmstats->syncp);
+        }
+
         return dev->lstats == NULL ? -ENOMEM : 0;
 }
 
diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c
index 50e43e64d51d..6574eb8766f9 100644
--- a/drivers/net/team/team.c
+++ b/drivers/net/team/team.c
@@ -1540,6 +1540,12 @@ static int team_init(struct net_device *dev)
         if (!team->pcpu_stats)
                 return -ENOMEM;
 
+        for_each_possible_cpu(i) {
+                struct team_pcpu_stats *team_stats;
+                team_stats = per_cpu_ptr(team->pcpu_stats, i);
+                u64_stats_init(&team_stats->syncp);
+        }
+
         for (i = 0; i < TEAM_PORT_HASHENTRIES; i++)
                 INIT_HLIST_HEAD(&team->en_port_hlist[i]);
         INIT_LIST_HEAD(&team->port_list);
diff --git a/drivers/net/team/team_mode_loadbalance.c b/drivers/net/team/team_mode_loadbalance.c
index 829a9cd2b4da..d671fc3ac5ac 100644
--- a/drivers/net/team/team_mode_loadbalance.c
+++ b/drivers/net/team/team_mode_loadbalance.c
@@ -570,7 +570,7 @@ static int lb_init(struct team *team)
 {
         struct lb_priv *lb_priv = get_lb_priv(team);
         lb_select_tx_port_func_t *func;
-        int err;
+        int i, err;
 
         /* set default tx port selector */
         func = lb_select_tx_port_get_func("hash");
@@ -588,6 +588,13 @@ static int lb_init(struct team *team)
                 goto err_alloc_pcpu_stats;
         }
 
+        for_each_possible_cpu(i) {
+                struct lb_pcpu_stats *team_lb_stats;
+                team_lb_stats = per_cpu_ptr(lb_priv->pcpu_stats, i);
+                u64_stats_init(&team_lb_stats->syncp);
+        }
+
+
         INIT_DELAYED_WORK(&lb_priv->ex->stats.refresh_dw, lb_stats_refresh);
 
         err = team_options_register(team, lb_options, ARRAY_SIZE(lb_options));
diff --git a/drivers/net/veth.c b/drivers/net/veth.c
index eee1f19ef1e9..46e83e3fe999 100644
--- a/drivers/net/veth.c
+++ b/drivers/net/veth.c
@@ -230,10 +230,18 @@ static int veth_change_mtu(struct net_device *dev, int new_mtu)
 
 static int veth_dev_init(struct net_device *dev)
 {
+        int i;
+
         dev->vstats = alloc_percpu(struct pcpu_vstats);
         if (!dev->vstats)
                 return -ENOMEM;
 
+        for_each_possible_cpu(i) {
+                struct pcpu_vstats *veth_stats;
+                veth_stats = per_cpu_ptr(dev->vstats, i);
+                u64_stats_init(&veth_stats->syncp);
+        }
+
         return 0;
 }
 
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 9fbdfcd1e1a0..ee384f3d612b 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -1569,6 +1569,14 @@ static int virtnet_probe(struct virtio_device *vdev)
         if (vi->stats == NULL)
                 goto free;
 
+        for_each_possible_cpu(i) {
+                struct virtnet_stats *virtnet_stats;
+                virtnet_stats = per_cpu_ptr(vi->stats, i);
+                u64_stats_init(&virtnet_stats->tx_syncp);
+                u64_stats_init(&virtnet_stats->rx_syncp);
+        }
+
+
         vi->vq_index = alloc_percpu(int);
         if (vi->vq_index == NULL)
                 goto free_stats;
diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 2ef5b6219f3f..01ab64d5f9a4 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -1884,11 +1884,19 @@ static int vxlan_init(struct net_device *dev)
         struct vxlan_dev *vxlan = netdev_priv(dev);
         struct vxlan_net *vn = net_generic(dev_net(dev), vxlan_net_id);
         struct vxlan_sock *vs;
+        int i;
 
         dev->tstats = alloc_percpu(struct pcpu_tstats);
         if (!dev->tstats)
                 return -ENOMEM;
 
+        for_each_possible_cpu(i) {
+                struct pcpu_tstats *vxlan_stats;
+                vxlan_stats = per_cpu_ptr(dev->tstats, i);
+                u64_stats_init(&vxlan_stats->syncp);
+        }
+
+
         spin_lock(&vn->sock_lock);
         vs = vxlan_find_sock(dev_net(dev), vxlan->dst_port);
         if (vs) {
diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index 36808bf25677..54223ac6d8a6 100644
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -1338,6 +1338,12 @@ static struct net_device *xennet_create_dev(struct xenbus_device *dev)
         if (np->stats == NULL)
                 goto exit;
 
+        for_each_possible_cpu(i) {
+                struct netfront_stats *xen_nf_stats;
+                xen_nf_stats = per_cpu_ptr(np->stats, i);
+                u64_stats_init(&xen_nf_stats->syncp);
+        }
+
         /* Initialise tx_skbs as a free chain containing every entry. */
         np->tx_skb_freelist = 0;
         for (i = 0; i < NET_TX_RING_SIZE; i++) {