[RFC PATCH 17/30] net/netpolicy: support CPU hotplug

kan.liang
2016-07-18T14:31:45Z

For CPU hotplug, the net policy module will rebuild the sys map and
object list.

Signed-off-by: Kan Liang <kan.liang@intel.com>
---
net/core/netpolicy.c | 78 ++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 78 insertions(+)

diff --git a/net/core/netpolicy.c b/net/core/netpolicy.c
index 2a04fcf..46af407 100644
--- a/net/core/netpolicy.c
+++ b/net/core/netpolicy.c
@@ -37,6 +37,7 @@
#include <net/net_namespace.h>
#include <linux/sort.h>
#include <linux/ctype.h>
+#include <linux/cpu.h>

static int netpolicy_get_dev_info(struct net_device *dev,
struct netpolicy_dev_info *d_info)
@@ -838,6 +839,75 @@ static struct notifier_block netpolicy_dev_notf = {
.notifier_call = netpolicy_notify,
};

+/**
+ * update_netpolicy_sys_map() - rebuild the sys map and object list
+ *
+ * This function go through all the available net policy supported device,
+ * and rebuild sys map and object list.
+ *
+ */
+void update_netpolicy_sys_map(void)
+{
+ struct net *net;
+ struct net_device *dev, *aux;
+ enum netpolicy_name cur_policy;
+
+ for_each_net(net) {
+ for_each_netdev_safe(net, dev, aux) {
+ spin_lock(&dev->np_lock);
+ if (!dev->netpolicy)
+ goto unlock;
+ cur_policy = dev->netpolicy->cur_policy;
+ if (cur_policy == NET_POLICY_NONE)
+ goto unlock;
+
+ dev->netpolicy->cur_policy = NET_POLICY_NONE;
+
+ /* rebuild everything */
+ netpolicy_disable(dev);
+ netpolicy_enable(dev);
+ if (netpolicy_gen_obj_list(dev, cur_policy)) {
+ pr_warn("NETPOLICY: Failed to generate "
+ "netpolicy object list for dev %s\n",
+ dev->name);
+ netpolicy_disable(dev);
+ goto unlock;
+ }
+ if (dev->netdev_ops->ndo_set_net_policy(dev, cur_policy)) {
+ pr_warn("NETPOLICY: Failed to set "
+ "netpolicy for dev %s\n",
+ dev->name);
+ netpolicy_disable(dev);
+ goto unlock;
+ }
+
+ dev->netpolicy->cur_policy = cur_policy;
+unlock:
+ spin_unlock(&dev->np_lock);
+ }
+ }
+}
+
+static int netpolicy_cpu_callback(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
+{
+ switch (action & ~CPU_TASKS_FROZEN) {
+ case CPU_ONLINE:
+ update_netpolicy_sys_map();
+ break;
+ case CPU_DYING:
+ update_netpolicy_sys_map();
+ break;
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block netpolicy_cpu_notifier = {
+ &netpolicy_cpu_callback,
+ NULL,
+ 0
+};
+
static int __init netpolicy_init(void)
{
int ret;
@@ -846,6 +916,10 @@ static int __init netpolicy_init(void)
if (!ret)
register_netdevice_notifier(&netpolicy_dev_notf);

+ cpu_notifier_register_begin();
+ __register_cpu_notifier(&netpolicy_cpu_notifier);
+ cpu_notifier_register_done();
+
return ret;
}

@@ -853,6 +927,10 @@ static void __exit netpolicy_exit(void)
{
unregister_netdevice_notifier(&netpolicy_dev_notf);
unregister_pernet_subsys(&netpolicy_net_ops);
+
+ cpu_notifier_register_begin();
+ __unregister_cpu_notifier(&netpolicy_cpu_notifier);
+ cpu_notifier_register_done();
}

subsys_initcall(netpolicy_init);
--
2.5.5