netdev - [PATCH net-next 7/7] openvswitch: Use RCU callback when detaching netdevices.

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

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1354214149-33651-8-git-send-email-jesse@nicira.com>
Date:	Thu, 29 Nov 2012 10:35:49 -0800
From:	Jesse Gross <jesse@...ira.com>
To:	David Miller <davem@...emloft.net>
Cc:	netdev@...r.kernel.org, dev@...nvswitch.org,
	Justin Pettit <jpettit@...ira.com>
Subject: [PATCH net-next 7/7] openvswitch: Use RCU callback when detaching netdevices.

Currently, each time a device is detached from an OVS datapath
we call synchronize RCU before freeing associated data structures.
However, if a bridge is deleted (which detaches all ports) when
many devices are connected then there can be a long delay.  This
switches to use call_rcu() to group the cost together.

Reported-by: Justin Pettit <jpettit@...ira.com>
Signed-off-by: Jesse Gross <jesse@...ira.com>
---
 net/openvswitch/vport-netdev.c |   14 ++++++++++----
 net/openvswitch/vport-netdev.h |    3 +++
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/net/openvswitch/vport-netdev.c b/net/openvswitch/vport-netdev.c
index a903348..a9327e2 100644
--- a/net/openvswitch/vport-netdev.c
+++ b/net/openvswitch/vport-netdev.c
@@ -114,6 +114,15 @@ error:
 	return ERR_PTR(err);
 }
 
+static void free_port_rcu(struct rcu_head *rcu)
+{
+	struct netdev_vport *netdev_vport = container_of(rcu,
+					struct netdev_vport, rcu);
+
+	dev_put(netdev_vport->dev);
+	ovs_vport_free(vport_from_priv(netdev_vport));
+}
+
 static void netdev_destroy(struct vport *vport)
 {
 	struct netdev_vport *netdev_vport = netdev_vport_priv(vport);
@@ -122,10 +131,7 @@ static void netdev_destroy(struct vport *vport)
 	netdev_rx_handler_unregister(netdev_vport->dev);
 	dev_set_promiscuity(netdev_vport->dev, -1);
 
-	synchronize_rcu();
-
-	dev_put(netdev_vport->dev);
-	ovs_vport_free(vport);
+	call_rcu(&netdev_vport->rcu, free_port_rcu);
 }
 
 const char *ovs_netdev_get_name(const struct vport *vport)
diff --git a/net/openvswitch/vport-netdev.h b/net/openvswitch/vport-netdev.h
index f7072a2..6478079 100644
--- a/net/openvswitch/vport-netdev.h
+++ b/net/openvswitch/vport-netdev.h
@@ -20,12 +20,15 @@
 #define VPORT_NETDEV_H 1
 
 #include <linux/netdevice.h>
+#include <linux/rcupdate.h>
 
 #include "vport.h"
 
 struct vport *ovs_netdev_get_vport(struct net_device *dev);
 
 struct netdev_vport {
+	struct rcu_head rcu;
+
 	struct net_device *dev;
 };
 
-- 
1.7.9.5

--
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