From: Cong Wang <amwang@redhat.com>
To: netdev@vger.kernel.org
Cc: Cong Wang <amwang@redhat.com>, "David S. Miller" <davem@davemloft.net>
Subject: [PATCH 02/14] netpoll: make __netpoll_cleanup non-block
Date: Fri, 10 Aug 2012 15:10:25 +0800 [thread overview]
Message-ID: <1344582637-18261-3-git-send-email-amwang@redhat.com> (raw)
In-Reply-To: <1344582637-18261-1-git-send-email-amwang@redhat.com>
Like the previous patch, slave_disable_netpoll() and __netpoll_cleanup()
may be called with read_lock() held too, so we should make them
non-block, by moving the cleanup and kfree() to call_rcu_bh() callbacks.
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
---
drivers/net/bonding/bond_main.c | 4 +--
include/linux/netpoll.h | 3 ++
net/8021q/vlan_dev.c | 6 +----
net/bridge/br_device.c | 6 +----
net/core/netpoll.c | 42 +++++++++++++++++++++++++++++---------
5 files changed, 38 insertions(+), 23 deletions(-)
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 8697136..e428916 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1257,9 +1257,7 @@ static inline void slave_disable_netpoll(struct slave *slave)
return;
slave->np = NULL;
- synchronize_rcu_bh();
- __netpoll_cleanup(np);
- kfree(np);
+ __netpoll_free_rcu(np);
}
static inline bool slave_dev_support_netpoll(struct net_device *slave_dev)
{
diff --git a/include/linux/netpoll.h b/include/linux/netpoll.h
index bf2d51e..907812e 100644
--- a/include/linux/netpoll.h
+++ b/include/linux/netpoll.h
@@ -23,6 +23,7 @@ struct netpoll {
u8 remote_mac[ETH_ALEN];
struct list_head rx; /* rx_np list element */
+ struct rcu_head rcu;
};
struct netpoll_info {
@@ -38,6 +39,7 @@ struct netpoll_info {
struct delayed_work tx_work;
struct netpoll *netpoll;
+ struct rcu_head rcu;
};
void netpoll_send_udp(struct netpoll *np, const char *msg, int len);
@@ -48,6 +50,7 @@ int netpoll_setup(struct netpoll *np);
int netpoll_trap(void);
void netpoll_set_trap(int trap);
void __netpoll_cleanup(struct netpoll *np);
+void __netpoll_free_rcu(struct netpoll *np);
void netpoll_cleanup(struct netpoll *np);
int __netpoll_rx(struct sk_buff *skb);
void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb,
diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c
index ee4ae09..b65623f 100644
--- a/net/8021q/vlan_dev.c
+++ b/net/8021q/vlan_dev.c
@@ -704,11 +704,7 @@ static void vlan_dev_netpoll_cleanup(struct net_device *dev)
info->netpoll = NULL;
- /* Wait for transmitting packets to finish before freeing. */
- synchronize_rcu_bh();
-
- __netpoll_cleanup(netpoll);
- kfree(netpoll);
+ __netpoll_free_rcu(netpoll);
}
#endif /* CONFIG_NET_POLL_CONTROLLER */
diff --git a/net/bridge/br_device.c b/net/bridge/br_device.c
index ed0e0f9..f41ba40 100644
--- a/net/bridge/br_device.c
+++ b/net/bridge/br_device.c
@@ -267,11 +267,7 @@ void br_netpoll_disable(struct net_bridge_port *p)
p->np = NULL;
- /* Wait for transmitting packets to finish before freeing. */
- synchronize_rcu_bh();
-
- __netpoll_cleanup(np);
- kfree(np);
+ __netpoll_free_rcu(np);
}
#endif
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index 37cc854..dc17f1d 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -878,6 +878,24 @@ static int __init netpoll_init(void)
}
core_initcall(netpoll_init);
+static void rcu_cleanup_netpoll_info(struct rcu_head *rcu_head)
+{
+ struct netpoll_info *npinfo =
+ container_of(rcu_head, struct netpoll_info, rcu);
+
+ skb_queue_purge(&npinfo->arp_tx);
+ skb_queue_purge(&npinfo->txq);
+
+ /* we can't call cancel_delayed_work_sync here, as we are in softirq */
+ cancel_delayed_work(&npinfo->tx_work);
+
+ /* clean after last, unfinished work */
+ __skb_queue_purge(&npinfo->txq);
+ /* now cancel it again */
+ cancel_delayed_work(&npinfo->tx_work);
+ kfree(npinfo);
+}
+
void __netpoll_cleanup(struct netpoll *np)
{
struct netpoll_info *npinfo;
@@ -903,20 +921,24 @@ void __netpoll_cleanup(struct netpoll *np)
ops->ndo_netpoll_cleanup(np->dev);
RCU_INIT_POINTER(np->dev->npinfo, NULL);
+ call_rcu_bh(&npinfo->rcu, rcu_cleanup_netpoll_info);
+ }
+}
+EXPORT_SYMBOL_GPL(__netpoll_cleanup);
- /* avoid racing with NAPI reading npinfo */
- synchronize_rcu_bh();
+static void rcu_cleanup_netpoll(struct rcu_head *rcu_head)
+{
+ struct netpoll *np = container_of(rcu_head, struct netpoll, rcu);
- skb_queue_purge(&npinfo->arp_tx);
- skb_queue_purge(&npinfo->txq);
- cancel_delayed_work_sync(&npinfo->tx_work);
+ __netpoll_cleanup(np);
+ kfree(np);
+}
- /* clean after last, unfinished work */
- __skb_queue_purge(&npinfo->txq);
- kfree(npinfo);
- }
+void __netpoll_free_rcu(struct netpoll *np)
+{
+ call_rcu_bh(&np->rcu, rcu_cleanup_netpoll);
}
-EXPORT_SYMBOL_GPL(__netpoll_cleanup);
+EXPORT_SYMBOL_GPL(__netpoll_free_rcu);
void netpoll_cleanup(struct netpoll *np)
{
--
1.7.7.6
next prev parent reply other threads:[~2012-08-10 7:10 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-08-10 7:10 [PATCH v4 00/14] some netpoll and netconsole fixes Cong Wang
2012-08-10 7:10 ` [PATCH 01/14] netpoll: use GFP_ATOMIC in slave_enable_netpoll() and __netpoll_setup() Cong Wang
2012-08-10 7:10 ` Cong Wang [this message]
2012-08-10 7:10 ` [PATCH 03/14] netconsole: do not release spin_lock when calling __netpoll_cleanup Cong Wang
2012-08-10 7:10 ` [PATCH 04/14] netpoll: take rcu_read_lock_bh() in netpoll_rx() Cong Wang
2012-08-10 7:10 ` [PATCH 05/14] netpoll: use netpoll_rx_on() " Cong Wang
2012-08-10 7:10 ` [PATCH 06/14] netpoll: take rcu_read_lock_bh() in netpoll_send_skb_on_dev() Cong Wang
2012-08-10 7:10 ` [PATCH 07/14] bridge: add some comments for NETDEV_RELEASE Cong Wang
2012-08-10 7:10 ` [PATCH 08/14] bridge: use list_for_each_entry() in netpoll functions Cong Wang
2012-08-10 7:10 ` [PATCH 09/14] netpoll: check netpoll tx status on the right device Cong Wang
2012-08-10 7:20 ` Jiri Pirko
2012-08-10 7:52 ` Cong Wang
2012-08-10 8:32 ` Jiri Pirko
2012-08-10 7:10 ` [PATCH 10/14] netpoll: convert several functions to bool Cong Wang
2012-08-10 7:10 ` [PATCH 11/14] vlan: clean up vlan_dev_hard_start_xmit() Cong Wang
2012-08-10 7:14 ` Patrick McHardy
2012-08-10 7:47 ` Cong Wang
2012-08-10 7:10 ` [PATCH 12/14] netpoll: handle vlan tags in netpoll tx and rx path Cong Wang
2012-08-10 7:10 ` [PATCH 13/14] netpoll: re-enable irq in poll_napi() Cong Wang
2012-08-10 7:10 ` [PATCH 14/14] netconsole.txt: revision of examples for the receiver of kernel messages Cong Wang
-- strict thread matches above, loose matches on Subject: below --
2012-08-09 15:00 [PATCH v3 0/14] some netpoll and netconsole fixes Cong Wang
2012-08-09 15:00 ` [PATCH 02/14] netpoll: make __netpoll_cleanup non-block Cong Wang
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