X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=net%2Fcore%2Fdst.c;h=470c05bc4cb2bd513f1ba37002a81f46266c8905;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=571ef1f2c4678f122f82dceffc2914f07a4080f9;hpb=9213980e6a70d8473e0ffd4b39ab5b6caaba9ff5;p=linux-2.6.git

diff --git a/net/core/dst.c b/net/core/dst.c
index 571ef1f2c..470c05bc4 100644
--- a/net/core/dst.c
+++ b/net/core/dst.c
@@ -32,19 +32,19 @@ static struct dst_entry 	*dst_garbage_list;
 #if RT_CACHE_DEBUG >= 2 
 static atomic_t			 dst_total = ATOMIC_INIT(0);
 #endif
-static spinlock_t		 dst_lock = SPIN_LOCK_UNLOCKED;
+static DEFINE_SPINLOCK(dst_lock);
 
 static unsigned long dst_gc_timer_expires;
 static unsigned long dst_gc_timer_inc = DST_GC_MAX;
 static void dst_run_gc(unsigned long);
 static void ___dst_free(struct dst_entry * dst);
 
-static struct timer_list dst_gc_timer =
-	TIMER_INITIALIZER(dst_run_gc, DST_GC_MIN, 0);
+static DEFINE_TIMER(dst_gc_timer, dst_run_gc, DST_GC_MIN, 0);
 
 static void dst_run_gc(unsigned long dummy)
 {
 	int    delayed = 0;
+	int    work_performed;
 	struct dst_entry * dst, **dstp;
 
 	if (!spin_trylock(&dst_lock)) {
@@ -52,9 +52,9 @@ static void dst_run_gc(unsigned long dummy)
 		return;
 	}
 
-
 	del_timer(&dst_gc_timer);
 	dstp = &dst_garbage_list;
+	work_performed = 0;
 	while ((dst = *dstp) != NULL) {
 		if (atomic_read(&dst->__refcnt)) {
 			dstp = &dst->next;
@@ -62,6 +62,7 @@ static void dst_run_gc(unsigned long dummy)
 			continue;
 		}
 		*dstp = dst->next;
+		work_performed = 1;
 
 		dst = dst_destroy(dst);
 		if (dst) {
@@ -86,9 +87,14 @@ static void dst_run_gc(unsigned long dummy)
 		dst_gc_timer_inc = DST_GC_MAX;
 		goto out;
 	}
-	if ((dst_gc_timer_expires += dst_gc_timer_inc) > DST_GC_MAX)
-		dst_gc_timer_expires = DST_GC_MAX;
-	dst_gc_timer_inc += DST_GC_INC;
+	if (!work_performed) {
+		if ((dst_gc_timer_expires += dst_gc_timer_inc) > DST_GC_MAX)
+			dst_gc_timer_expires = DST_GC_MAX;
+		dst_gc_timer_inc += DST_GC_INC;
+	} else {
+		dst_gc_timer_inc = DST_GC_INC;
+		dst_gc_timer_expires = DST_GC_MIN;
+	}
 	dst_gc_timer.expires = jiffies + dst_gc_timer_expires;
 #if RT_CACHE_DEBUG >= 2
 	printk("dst_total: %d/%d %ld\n",
@@ -106,9 +112,9 @@ static int dst_discard_in(struct sk_buff *skb)
 	return 0;
 }
 
-static int dst_discard_out(struct sk_buff **pskb)
+static int dst_discard_out(struct sk_buff *skb)
 {
-	kfree_skb(*pskb);
+	kfree_skb(skb);
 	return 0;
 }
 
@@ -169,6 +175,8 @@ struct dst_entry *dst_destroy(struct dst_entry * dst)
 	struct neighbour *neigh;
 	struct hh_cache *hh;
 
+	smp_rmb();
+
 again:
 	neigh = dst->neighbour;
 	hh = dst->hh;
@@ -196,13 +204,15 @@ again:
 
 	dst = child;
 	if (dst) {
+		int nohash = dst->flags & DST_NOHASH;
+
 		if (atomic_dec_and_test(&dst->__refcnt)) {
 			/* We were real parent of this dst, so kill child. */
-			if (dst->flags&DST_NOHASH)
+			if (nohash)
 				goto again;
 		} else {
 			/* Child is still referenced, return it for freeing. */
-			if (dst->flags&DST_NOHASH)
+			if (nohash)
 				return dst;
 			/* Child is still in his hash table */
 		}
@@ -210,6 +220,38 @@ again:
 	return NULL;
 }
 
+/* Dirty hack. We did it in 2.2 (in __dst_free),
+ * we have _very_ good reasons not to repeat
+ * this mistake in 2.3, but we have no choice
+ * now. _It_ _is_ _explicit_ _deliberate_
+ * _race_ _condition_.
+ *
+ * Commented and originally written by Alexey.
+ */
+static inline void dst_ifdown(struct dst_entry *dst, struct net_device *dev,
+			      int unregister)
+{
+	if (dst->ops->ifdown)
+		dst->ops->ifdown(dst, dev, unregister);
+
+	if (dev != dst->dev)
+		return;
+
+	if (!unregister) {
+		dst->input = dst_discard_in;
+		dst->output = dst_discard_out;
+	} else {
+		dst->dev = &loopback_dev;
+		dev_hold(&loopback_dev);
+		dev_put(dev);
+		if (dst->neighbour && dst->neighbour->dev == dev) {
+			dst->neighbour->dev = &loopback_dev;
+			dev_put(dev);
+			dev_hold(&loopback_dev);
+		}
+	}
+}
+
 static int dst_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
 {
 	struct net_device *dev = ptr;
@@ -220,31 +262,7 @@ static int dst_dev_event(struct notifier_block *this, unsigned long event, void
 	case NETDEV_DOWN:
 		spin_lock_bh(&dst_lock);
 		for (dst = dst_garbage_list; dst; dst = dst->next) {
-			if (dst->dev == dev) {
-				/* Dirty hack. We did it in 2.2 (in __dst_free),
-				   we have _very_ good reasons not to repeat
-				   this mistake in 2.3, but we have no choice
-				   now. _It_ _is_ _explicit_ _deliberate_
-				   _race_ _condition_.
-				 */
-				if (event!=NETDEV_DOWN &&
-				    dst->output == dst_discard_out) {
-					dst->dev = &loopback_dev;
-					dev_hold(&loopback_dev);
-					dev_put(dev);
-					dst->output = dst_discard_out;
-					if (dst->neighbour && dst->neighbour->dev == dev) {
-						dst->neighbour->dev = &loopback_dev;
-						dev_put(dev);
-						dev_hold(&loopback_dev);
-					}
-				} else {
-					dst->input = dst_discard_in;
-					dst->output = dst_discard_out;
-				}
-				if (dst->ops->ifdown)
-					dst->ops->ifdown(dst, event != NETDEV_DOWN);
-			}
+			dst_ifdown(dst, dev, event != NETDEV_DOWN);
 		}
 		spin_unlock_bh(&dst_lock);
 		break;
@@ -252,7 +270,7 @@ static int dst_dev_event(struct notifier_block *this, unsigned long event, void
 	return NOTIFY_DONE;
 }
 
-struct notifier_block dst_dev_notifier = {
+static struct notifier_block dst_dev_notifier = {
 	.notifier_call	= dst_dev_event,
 };