Re: [patch 2/7] CAN: Add PF_CAN core module

Oliver Hartkopp
2007-05-18T21:06:54Z

Hello Paul,

as you may see in the attached SVN-log i changed some code according
your suggestions.
I additionally made some clarifications of function names.

If you would like to see the af_can.c completely please visit:
http://svn.berlios.de/svnroot/repos/socketcan/trunk/kernel/2.6/net/can/af_can.c

But this code in the projekt SVN is working for several kernel versions
(which is removed by some scripts when creating a LKML netdev patch) -
just for your information.

Best regards,
Oliver

-------- Original-Nachricht --------
Betreff: r311 - trunk/kernel/2.6/net/can
Datum: Fri, 18 May 2007 21:47:15 +0200
Von: hartkopp@mail.berlios.de
An: socketcan-commit@lists.berlios.de

Author: hartkopp
Date: 2007-05-18 21:47:14 +0200 (Fri, 18 May 2007)
New Revision: 311

Modified:
trunk/kernel/2.6/net/can/af_can.c
Log:
Updated RCU removal of dev_rcv_lists structures in the case of CAN-interfaces
going down (in can_notifier). Thanks to Paul E. McKenny (IBM) who gave this
hint on netdev kernel mailinglist.

Modified: trunk/kernel/2.6/net/can/af_can.c
===================================================================
--- trunk/kernel/2.6/net/can/af_can.c 2007-05-16 09:03:21 UTC (rev 310)
+++ trunk/kernel/2.6/net/can/af_can.c 2007-05-18 19:47:14 UTC (rev 311)
@@ -454,31 +454,48 @@
}
EXPORT_SYMBOL(can_rx_register);

-static void can_rcv_lists_delete(struct rcu_head *rp)
+static void can_rx_delete_list(struct hlist_head *rl)
{
+ struct receiver *r;
+ struct hlist_node *n;
+
+ hlist_for_each_entry_rcu(r, n, rl, list) {
+ hlist_del_rcu(&r->list);
+ kmem_cache_free(rcv_cache, r);
+ }
+}
+
+/*
+ * can_rx_delete_device - rcu callback for dev_rcv_lists structure removal
+ */
+static void can_rx_delete_device(struct rcu_head *rp)
+{
struct dev_rcv_lists *d = container_of(rp, struct dev_rcv_lists, rcu);
+ int i;

+ /* remove all receivers hooked at this netdevice */
+ can_rx_delete_list(&d->rx_err);
+ can_rx_delete_list(&d->rx_all);
+ can_rx_delete_list(&d->rx_fil);
+ can_rx_delete_list(&d->rx_inv);
+ can_rx_delete_list(&d->rx_eff);
+
+ for (i = 0; i < 2048; i++)
+ can_rx_delete_list(&d->rx_sff[i]);
+
kfree(d);
}

-static void can_rx_delete(struct rcu_head *rp)
+/*
+ * can_rx_delete_receiver - rcu callback for single receiver entry removal
+ */
+static void can_rx_delete_receiver(struct rcu_head *rp)
{
struct receiver *r = container_of(rp, struct receiver, rcu);

kmem_cache_free(rcv_cache, r);
}

-static void can_rx_delete_all(struct hlist_head *rl)
-{
- struct receiver *r;
- struct hlist_node *n;
-
- hlist_for_each_entry_rcu(r, n, rl, list) {
- hlist_del_rcu(&r->list);
- call_rcu(&r->rcu, can_rx_delete);
- }
-}
-
/**
* can_rx_unregister - unsubscribe CAN frames from a specific interface
* @dev: pointer to netdevice (NULL => unsubcribe from 'all' CAN devices list)
@@ -556,7 +573,7 @@

/* schedule the receiver item for deletion */
if (r)
- call_rcu(&r->rcu, can_rx_delete);
+ call_rcu(&r->rcu, can_rx_delete_receiver);

return ret;
}
@@ -945,7 +962,6 @@
struct net_device *dev = (struct net_device *)data;
struct notifier *n;
struct dev_rcv_lists *d;
- int i;

DBG("called for %s, msg = %lu\n", dev->name, msg);

@@ -986,25 +1002,16 @@
spin_lock_bh(&rcv_lists_lock);

d = find_dev_rcv_lists(dev);
- if (d) {
+ if (d)
hlist_del_rcu(&d->list);
-
- /* remove all receivers hooked at this netdevice */
- can_rx_delete_all(&d->rx_err);
- can_rx_delete_all(&d->rx_all);
- can_rx_delete_all(&d->rx_fil);
- can_rx_delete_all(&d->rx_inv);
- can_rx_delete_all(&d->rx_eff);
- for (i = 0; i < 2048; i++)
- can_rx_delete_all(&d->rx_sff[i]);
- } else
+ else
printk(KERN_ERR "can: notifier: receive list not "
"found for dev %s\n", dev->name);

spin_unlock_bh(&rcv_lists_lock);

if (d)
- call_rcu(&d->rcu, can_rcv_lists_delete);
+ call_rcu(&d->rcu, can_rx_delete_device);

break;
}

_______________________________________________
Socketcan-commit mailing list
Socketcan-commit@lists.berlios.de