net: allow GFP_HIGHMEM in __vmalloc()
[linux-2.6.git] / net / core / drop_monitor.c
index a6c2ac2..36e603c 100644 (file)
 #include <linux/percpu.h>
 #include <linux/timer.h>
 #include <linux/bitops.h>
+#include <linux/slab.h>
 #include <net/genetlink.h>
 #include <net/netevent.h>
 
-#include <trace/skb.h>
-#include <trace/napi.h>
+#include <trace/events/skb.h>
+#include <trace/events/napi.h>
 
 #include <asm/unaligned.h>
 
@@ -41,7 +42,7 @@ static void send_dm_alert(struct work_struct *unused);
  * netlink alerts
  */
 static int trace_state = TRACE_OFF;
-static spinlock_t trace_state_lock = SPIN_LOCK_UNLOCKED;
+static DEFINE_SPINLOCK(trace_state_lock);
 
 struct per_cpu_dm_data {
        struct work_struct dm_alert_work;
@@ -52,6 +53,7 @@ struct per_cpu_dm_data {
 
 struct dm_hw_stat_delta {
        struct net_device *dev;
+       unsigned long last_rx;
        struct list_head list;
        struct rcu_head rcu;
        unsigned long last_drop_val;
@@ -170,27 +172,35 @@ out:
        return;
 }
 
-static void trace_kfree_skb_hit(struct sk_buff *skb, void *location)
+static void trace_kfree_skb_hit(void *ignore, struct sk_buff *skb, void *location)
 {
        trace_drop_common(skb, location);
 }
 
-static void trace_napi_poll_hit(struct napi_struct *napi)
+static void trace_napi_poll_hit(void *ignore, struct napi_struct *napi)
 {
        struct dm_hw_stat_delta *new_stat;
 
        /*
-        * Ratelimit our check time to dm_hw_check_delta jiffies
+        * Don't check napi structures with no associated device
         */
-       if (!time_after(jiffies, napi->dev->last_rx + dm_hw_check_delta))
+       if (!napi->dev)
                return;
 
        rcu_read_lock();
        list_for_each_entry_rcu(new_stat, &hw_stats_list, list) {
+               /*
+                * only add a note to our monitor buffer if:
+                * 1) this is the dev we received on
+                * 2) its after the last_rx delta
+                * 3) our rx_dropped count has gone up
+                */
                if ((new_stat->dev == napi->dev)  &&
+                   (time_after(jiffies, new_stat->last_rx + dm_hw_check_delta)) &&
                    (napi->dev->stats.rx_dropped != new_stat->last_drop_val)) {
                        trace_drop_common(NULL, NULL);
                        new_stat->last_drop_val = napi->dev->stats.rx_dropped;
+                       new_stat->last_rx = jiffies;
                        break;
                }
        }
@@ -213,14 +223,19 @@ static int set_all_monitor_traces(int state)
 
        spin_lock(&trace_state_lock);
 
+       if (state == trace_state) {
+               rc = -EAGAIN;
+               goto out_unlock;
+       }
+
        switch (state) {
        case TRACE_ON:
-               rc |= register_trace_kfree_skb(trace_kfree_skb_hit);
-               rc |= register_trace_napi_poll(trace_napi_poll_hit);
+               rc |= register_trace_kfree_skb(trace_kfree_skb_hit, NULL);
+               rc |= register_trace_napi_poll(trace_napi_poll_hit, NULL);
                break;
        case TRACE_OFF:
-               rc |= unregister_trace_kfree_skb(trace_kfree_skb_hit);
-               rc |= unregister_trace_napi_poll(trace_napi_poll_hit);
+               rc |= unregister_trace_kfree_skb(trace_kfree_skb_hit, NULL);
+               rc |= unregister_trace_napi_poll(trace_napi_poll_hit, NULL);
 
                tracepoint_synchronize_unregister();
 
@@ -241,11 +256,12 @@ static int set_all_monitor_traces(int state)
 
        if (!rc)
                trace_state = state;
+       else
+               rc = -EINPROGRESS;
 
+out_unlock:
        spin_unlock(&trace_state_lock);
 
-       if (rc)
-               return -EINPROGRESS;
        return rc;
 }
 
@@ -286,7 +302,7 @@ static int dropmon_net_event(struct notifier_block *ev_block,
                        goto out;
 
                new_stat->dev = dev;
-               INIT_RCU_HEAD(&new_stat->rcu);
+               new_stat->last_rx = jiffies;
                spin_lock(&trace_state_lock);
                list_add_rcu(&new_stat->list, &hw_stats_list);
                spin_unlock(&trace_state_lock);
@@ -331,9 +347,9 @@ static struct notifier_block dropmon_net_notifier = {
 
 static int __init init_net_drop_monitor(void)
 {
-       int cpu;
-       int rc, i, ret;
        struct per_cpu_dm_data *data;
+       int cpu, rc;
+
        printk(KERN_INFO "Initalizing network drop monitor service\n");
 
        if (sizeof(void *) > 8) {
@@ -341,21 +357,12 @@ static int __init init_net_drop_monitor(void)
                return -ENOSPC;
        }
 
-       if (genl_register_family(&net_drop_monitor_family) < 0) {
+       rc = genl_register_family_with_ops(&net_drop_monitor_family,
+                                          dropmon_ops,
+                                          ARRAY_SIZE(dropmon_ops));
+       if (rc) {
                printk(KERN_ERR "Could not create drop monitor netlink family\n");
-               return -EFAULT;
-       }
-
-       rc = -EFAULT;
-
-       for (i = 0; i < ARRAY_SIZE(dropmon_ops); i++) {
-               ret = genl_register_ops(&net_drop_monitor_family,
-                                       &dropmon_ops[i]);
-               if (ret) {
-                       printk(KERN_CRIT "Failed to register operation %d\n",
-                               dropmon_ops[i].cmd);
-                       goto out_unreg;
-               }
+               return rc;
        }
 
        rc = register_netdevice_notifier(&dropmon_net_notifier);