From: Rusty Russell <rusty@rustcorp.com.au>
To: John Levon <levon@movementarian.org>
Cc: oprofile-list@lists.sf.net, torvalds@transmeta.com,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] Module load notification take 3
Date: Thu, 27 Mar 2003 16:26:29 +1100 [thread overview]
Message-ID: <20030327062921.3D8932C08F@lists.samba.org> (raw)
In-Reply-To: Your message of "Thu, 27 Mar 2003 04:17:59 -0000." <20030327041759.GA4367@compsoc.man.ac.uk>
In message <20030327041759.GA4367@compsoc.man.ac.uk> you write:
> On Thu, Mar 27, 2003 at 01:20:23PM +1100, Rusty Russell wrote:
> ... and it's the same ill. Half-cleaned up stuff sucks. Either remove it
> or don't.
I like that attitude: I'm not sure I have the energy to match it 8)
However, please look at patch below.
> > That's because everyone realizes that the return value is useless.
>
> It detects one variant of unmatched register/unregister, so it cannot be
> said to be entirely useless. I would not call it entirely useful,
> though, I admit.
BUG() in the unregister makes sense I think (see patch).
> Beside the point though really, I appear to have made onto Linus'
> shitlist at last ... does this mean I finally graduated Linux School ?
Linus fades every so often. Has more to do with phase of the moon, I
think, than individuals.
Rusty.
--
Anyone who quotes me in their sig is an idiot. -- Rusty Russell.
Name: notifier_unregister should return void
Author: Rusty Russell
Status: Tested on 2.5.66-bk2
D: Noone uses the return value of notifier_chain_unregister and its
D: children: make it BUG() when unregistering a non-existent notifier,
D: and return void.
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.66-bk2/include/linux/cpufreq.h working-2.5.66-bk2-notifier/include/linux/cpufreq.h
--- linux-2.5.66-bk2/include/linux/cpufreq.h 2003-03-18 12:21:40.000000000 +1100
+++ working-2.5.66-bk2-notifier/include/linux/cpufreq.h 2003-03-27 15:41:52.000000000 +1100
@@ -29,7 +29,7 @@
*********************************************************************/
int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list);
-int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list);
+void cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list);
#define CPUFREQ_TRANSITION_NOTIFIER (0)
#define CPUFREQ_POLICY_NOTIFIER (1)
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.66-bk2/include/linux/inetdevice.h working-2.5.66-bk2-notifier/include/linux/inetdevice.h
--- linux-2.5.66-bk2/include/linux/inetdevice.h 2003-01-02 12:34:08.000000000 +1100
+++ working-2.5.66-bk2-notifier/include/linux/inetdevice.h 2003-03-27 15:59:02.000000000 +1100
@@ -77,7 +77,7 @@ struct in_ifaddr
};
extern int register_inetaddr_notifier(struct notifier_block *nb);
-extern int unregister_inetaddr_notifier(struct notifier_block *nb);
+extern void unregister_inetaddr_notifier(struct notifier_block *nb);
extern struct net_device *ip_dev_find(u32 addr);
extern int inet_addr_onlink(struct in_device *in_dev, u32 a, u32 b);
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.66-bk2/include/linux/netdevice.h working-2.5.66-bk2-notifier/include/linux/netdevice.h
--- linux-2.5.66-bk2/include/linux/netdevice.h 2003-03-27 12:11:45.000000000 +1100
+++ working-2.5.66-bk2-notifier/include/linux/netdevice.h 2003-03-27 15:41:49.000000000 +1100
@@ -487,7 +487,7 @@ extern int dev_queue_xmit(struct sk_buf
extern int register_netdevice(struct net_device *dev);
extern int unregister_netdevice(struct net_device *dev);
extern int register_netdevice_notifier(struct notifier_block *nb);
-extern int unregister_netdevice_notifier(struct notifier_block *nb);
+extern void unregister_netdevice_notifier(struct notifier_block *nb);
extern int call_netdevice_notifiers(unsigned long val, void *v);
extern int dev_new_index(void);
extern struct net_device *dev_get_by_index(int ifindex);
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.66-bk2/include/linux/netlink.h working-2.5.66-bk2-notifier/include/linux/netlink.h
--- linux-2.5.66-bk2/include/linux/netlink.h 2003-02-07 19:16:27.000000000 +1100
+++ working-2.5.66-bk2-notifier/include/linux/netlink.h 2003-03-27 15:42:20.000000000 +1100
@@ -114,7 +114,7 @@ extern int netlink_broadcast(struct sock
__u32 group, int allocation);
extern void netlink_set_err(struct sock *ssk, __u32 pid, __u32 group, int code);
extern int netlink_register_notifier(struct notifier_block *nb);
-extern int netlink_unregister_notifier(struct notifier_block *nb);
+extern void netlink_unregister_notifier(struct notifier_block *nb);
/*
* skb should fit one page. This choice is good for headerless malloc.
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.66-bk2/include/linux/notifier.h working-2.5.66-bk2-notifier/include/linux/notifier.h
--- linux-2.5.66-bk2/include/linux/notifier.h 2003-01-02 12:32:49.000000000 +1100
+++ working-2.5.66-bk2-notifier/include/linux/notifier.h 2003-03-27 15:37:31.000000000 +1100
@@ -22,7 +22,7 @@ struct notifier_block
#ifdef __KERNEL__
extern int notifier_chain_register(struct notifier_block **list, struct notifier_block *n);
-extern int notifier_chain_unregister(struct notifier_block **nl, struct notifier_block *n);
+extern void notifier_chain_unregister(struct notifier_block **nl, struct notifier_block *n);
extern int notifier_call_chain(struct notifier_block **n, unsigned long val, void *v);
#define NOTIFY_DONE 0x0000 /* Don't care */
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.66-bk2/include/linux/profile.h working-2.5.66-bk2-notifier/include/linux/profile.h
--- linux-2.5.66-bk2/include/linux/profile.h 2003-03-18 12:21:40.000000000 +1100
+++ working-2.5.66-bk2-notifier/include/linux/profile.h 2003-03-27 15:42:15.000000000 +1100
@@ -43,10 +43,10 @@ void profile_exit_mmap(struct mm_struct
int profile_event_register(enum profile_type, struct notifier_block * n);
-int profile_event_unregister(enum profile_type, struct notifier_block * n);
+void profile_event_unregister(enum profile_type, struct notifier_block * n);
int register_profile_notifier(struct notifier_block * nb);
-int unregister_profile_notifier(struct notifier_block * nb);
+void unregister_profile_notifier(struct notifier_block * nb);
/* profiling hook activated on each timer interrupt */
void profile_hook(struct pt_regs * regs);
@@ -58,9 +58,8 @@ static inline int profile_event_register
return -ENOSYS;
}
-static inline int profile_event_unregister(enum profile_type t, struct notifier_block * n)
+static inline void profile_event_unregister(enum profile_type t, struct notifier_block * n)
{
- return -ENOSYS;
}
#define profile_exit_task(a) do { } while (0)
@@ -72,9 +71,8 @@ static inline int register_profile_notif
return -ENOSYS;
}
-static inline int unregister_profile_notifier(struct notifier_block * nb)
+static inline void unregister_profile_notifier(struct notifier_block * nb)
{
- return -ENOSYS;
}
#define profile_hook(regs) do { } while (0)
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.66-bk2/include/linux/reboot.h working-2.5.66-bk2-notifier/include/linux/reboot.h
--- linux-2.5.66-bk2/include/linux/reboot.h 2003-02-07 19:17:54.000000000 +1100
+++ working-2.5.66-bk2-notifier/include/linux/reboot.h 2003-03-27 15:41:56.000000000 +1100
@@ -37,7 +37,7 @@
#include <linux/notifier.h>
extern int register_reboot_notifier(struct notifier_block *);
-extern int unregister_reboot_notifier(struct notifier_block *);
+extern void unregister_reboot_notifier(struct notifier_block *);
/*
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.66-bk2/include/net/addrconf.h working-2.5.66-bk2-notifier/include/net/addrconf.h
--- linux-2.5.66-bk2/include/net/addrconf.h 2003-03-25 12:17:31.000000000 +1100
+++ working-2.5.66-bk2-notifier/include/net/addrconf.h 2003-03-27 15:42:38.000000000 +1100
@@ -123,7 +123,7 @@ extern int ipv6_chk_acast_addr(struct
/* Device notifier */
extern int register_inet6addr_notifier(struct notifier_block *nb);
-extern int unregister_inet6addr_notifier(struct notifier_block *nb);
+extern void unregister_inet6addr_notifier(struct notifier_block *nb);
static inline struct inet6_dev *
__in6_dev_get(struct net_device *dev)
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.66-bk2/include/net/bluetooth/hci_core.h working-2.5.66-bk2-notifier/include/net/bluetooth/hci_core.h
--- linux-2.5.66-bk2/include/net/bluetooth/hci_core.h 2003-02-25 10:11:10.000000000 +1100
+++ working-2.5.66-bk2-notifier/include/net/bluetooth/hci_core.h 2003-03-27 15:42:35.000000000 +1100
@@ -467,7 +467,7 @@ static inline void hci_proto_encrypt_cfm
int hci_register_proto(struct hci_proto *hproto);
int hci_unregister_proto(struct hci_proto *hproto);
int hci_register_notifier(struct notifier_block *nb);
-int hci_unregister_notifier(struct notifier_block *nb);
+void hci_unregister_notifier(struct notifier_block *nb);
int hci_send_cmd(struct hci_dev *hdev, __u16 ogf, __u16 ocf, __u32 plen, void *param);
int hci_send_acl(struct hci_conn *conn, struct sk_buff *skb, __u16 flags);
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.66-bk2/kernel/cpufreq.c working-2.5.66-bk2-notifier/kernel/cpufreq.c
--- linux-2.5.66-bk2/kernel/cpufreq.c 2003-03-25 12:17:31.000000000 +1100
+++ working-2.5.66-bk2-notifier/kernel/cpufreq.c 2003-03-27 15:43:36.000000000 +1100
@@ -484,27 +484,22 @@ EXPORT_SYMBOL(cpufreq_register_notifier)
*
* Remove a driver from the CPU frequency notifier list.
*
- * This function may sleep, and has the same return conditions as
- * notifier_chain_unregister.
+ * This function may sleep.
*/
-int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list)
+void cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list)
{
- int ret;
-
down_write(&cpufreq_notifier_rwsem);
switch (list) {
case CPUFREQ_TRANSITION_NOTIFIER:
- ret = notifier_chain_unregister(&cpufreq_transition_notifier_list, nb);
+ notifier_chain_unregister(&cpufreq_transition_notifier_list, nb);
break;
case CPUFREQ_POLICY_NOTIFIER:
- ret = notifier_chain_unregister(&cpufreq_policy_notifier_list, nb);
+ notifier_chain_unregister(&cpufreq_policy_notifier_list, nb);
break;
default:
- ret = -EINVAL;
+ BUG();
}
up_write(&cpufreq_notifier_rwsem);
-
- return ret;
}
EXPORT_SYMBOL(cpufreq_unregister_notifier);
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.66-bk2/kernel/profile.c working-2.5.66-bk2-notifier/kernel/profile.c
--- linux-2.5.66-bk2/kernel/profile.c 2003-02-25 10:11:11.000000000 +1100
+++ working-2.5.66-bk2-notifier/kernel/profile.c 2003-03-27 15:44:06.000000000 +1100
@@ -97,26 +97,23 @@ int profile_event_register(enum profile_
}
-int profile_event_unregister(enum profile_type type, struct notifier_block * n)
+void profile_event_unregister(enum profile_type type, struct notifier_block * n)
{
- int err = -EINVAL;
-
down_write(&profile_rwsem);
switch (type) {
case EXIT_TASK:
- err = notifier_chain_unregister(&exit_task_notifier, n);
+ notifier_chain_unregister(&exit_task_notifier, n);
break;
case EXIT_MMAP:
- err = notifier_chain_unregister(&exit_mmap_notifier, n);
+ notifier_chain_unregister(&exit_mmap_notifier, n);
break;
case EXEC_UNMAP:
- err = notifier_chain_unregister(&exec_unmap_notifier, n);
+ notifier_chain_unregister(&exec_unmap_notifier, n);
break;
}
up_write(&profile_rwsem);
- return err;
}
static struct notifier_block * profile_listeners;
@@ -132,13 +129,11 @@ int register_profile_notifier(struct not
}
-int unregister_profile_notifier(struct notifier_block * nb)
+void unregister_profile_notifier(struct notifier_block * nb)
{
- int err;
write_lock_irq(&profile_lock);
- err = notifier_chain_unregister(&profile_listeners, nb);
+ notifier_chain_unregister(&profile_listeners, nb);
write_unlock_irq(&profile_lock);
- return err;
}
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.66-bk2/kernel/sys.c working-2.5.66-bk2-notifier/kernel/sys.c
--- linux-2.5.66-bk2/kernel/sys.c 2003-03-25 12:17:32.000000000 +1100
+++ working-2.5.66-bk2-notifier/kernel/sys.c 2003-03-27 16:07:33.000000000 +1100
@@ -111,11 +111,9 @@ int notifier_chain_register(struct notif
* @n: New entry in notifier chain
*
* Removes a notifier from a notifier chain.
- *
- * Returns zero on success, or %-ENOENT on failure.
*/
-int notifier_chain_unregister(struct notifier_block **nl, struct notifier_block *n)
+void notifier_chain_unregister(struct notifier_block **nl, struct notifier_block *n)
{
write_lock(¬ifier_lock);
while((*nl)!=NULL)
@@ -124,12 +122,12 @@ int notifier_chain_unregister(struct not
{
*nl=n->next;
write_unlock(¬ifier_lock);
- return 0;
+ return;
}
nl=&((*nl)->next);
}
write_unlock(¬ifier_lock);
- return -ENOENT;
+ BUG();
}
/**
@@ -187,13 +185,11 @@ int register_reboot_notifier(struct noti
*
* Unregisters a previously registered reboot
* notifier function.
- *
- * Returns zero on success, or %-ENOENT on failure.
*/
-int unregister_reboot_notifier(struct notifier_block * nb)
+void unregister_reboot_notifier(struct notifier_block * nb)
{
- return notifier_chain_unregister(&reboot_notifier_list, nb);
+ notifier_chain_unregister(&reboot_notifier_list, nb);
}
asmlinkage long sys_ni_syscall(void)
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.66-bk2/net/bluetooth/hci_core.c working-2.5.66-bk2-notifier/net/bluetooth/hci_core.c
--- linux-2.5.66-bk2/net/bluetooth/hci_core.c 2003-02-25 10:11:12.000000000 +1100
+++ working-2.5.66-bk2-notifier/net/bluetooth/hci_core.c 2003-03-27 15:44:54.000000000 +1100
@@ -83,9 +83,9 @@ int hci_register_notifier(struct notifie
return notifier_chain_register(&hci_notifier, nb);
}
-int hci_unregister_notifier(struct notifier_block *nb)
+void hci_unregister_notifier(struct notifier_block *nb)
{
- return notifier_chain_unregister(&hci_notifier, nb);
+ notifier_chain_unregister(&hci_notifier, nb);
}
void hci_notify(struct hci_dev *hdev, int event)
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.66-bk2/net/core/dev.c working-2.5.66-bk2-notifier/net/core/dev.c
--- linux-2.5.66-bk2/net/core/dev.c 2003-03-25 12:17:32.000000000 +1100
+++ working-2.5.66-bk2-notifier/net/core/dev.c 2003-03-27 15:45:14.000000000 +1100
@@ -912,13 +912,12 @@ int register_netdevice_notifier(struct n
*
* Unregister a notifier previously registered by
* register_netdevice_notifier(). The notifier is unlinked into the
- * kernel structures and may then be reused. A negative errno code
- * is returned on a failure.
+ * kernel structures and may then be reused.
*/
-int unregister_netdevice_notifier(struct notifier_block *nb)
+void unregister_netdevice_notifier(struct notifier_block *nb)
{
- return notifier_chain_unregister(&netdev_chain, nb);
+ notifier_chain_unregister(&netdev_chain, nb);
}
/**
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.66-bk2/net/ipv4/devinet.c working-2.5.66-bk2-notifier/net/ipv4/devinet.c
--- linux-2.5.66-bk2/net/ipv4/devinet.c 2003-02-11 14:26:21.000000000 +1100
+++ working-2.5.66-bk2-notifier/net/ipv4/devinet.c 2003-03-27 15:45:31.000000000 +1100
@@ -818,9 +818,9 @@ int register_inetaddr_notifier(struct no
return notifier_chain_register(&inetaddr_chain, nb);
}
-int unregister_inetaddr_notifier(struct notifier_block *nb)
+void unregister_inetaddr_notifier(struct notifier_block *nb)
{
- return notifier_chain_unregister(&inetaddr_chain, nb);
+ notifier_chain_unregister(&inetaddr_chain, nb);
}
/* Rename ifa_labels for a device name change. Make some effort to preserve existing
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.66-bk2/net/ipv6/addrconf.c working-2.5.66-bk2-notifier/net/ipv6/addrconf.c
--- linux-2.5.66-bk2/net/ipv6/addrconf.c 2003-03-25 12:17:33.000000000 +1100
+++ working-2.5.66-bk2-notifier/net/ipv6/addrconf.c 2003-03-27 15:45:42.000000000 +1100
@@ -2636,9 +2636,9 @@ int register_inet6addr_notifier(struct n
return notifier_chain_register(&inet6addr_chain, nb);
}
-int unregister_inet6addr_notifier(struct notifier_block *nb)
+void unregister_inet6addr_notifier(struct notifier_block *nb)
{
- return notifier_chain_unregister(&inet6addr_chain,nb);
+ notifier_chain_unregister(&inet6addr_chain,nb);
}
/*
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.66-bk2/net/netlink/af_netlink.c working-2.5.66-bk2-notifier/net/netlink/af_netlink.c
--- linux-2.5.66-bk2/net/netlink/af_netlink.c 2003-03-18 12:21:41.000000000 +1100
+++ working-2.5.66-bk2-notifier/net/netlink/af_netlink.c 2003-03-27 15:45:53.000000000 +1100
@@ -1023,9 +1023,9 @@ int netlink_register_notifier(struct not
return notifier_chain_register(&netlink_chain, nb);
}
-int netlink_unregister_notifier(struct notifier_block *nb)
+void netlink_unregister_notifier(struct notifier_block *nb)
{
- return notifier_chain_unregister(&netlink_chain, nb);
+ notifier_chain_unregister(&netlink_chain, nb);
}
struct proto_ops netlink_ops = {
prev parent reply other threads:[~2003-03-27 6:18 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-03-25 2:03 [PATCH 1/2] Module load notification take 3 John Levon
2003-03-25 2:13 ` [PATCH 2/2] " John Levon
2003-03-25 6:32 ` [PATCH 1/2] " Rusty Russell
2003-03-25 11:41 ` John Levon
2003-03-27 2:20 ` Rusty Russell
2003-03-27 4:17 ` John Levon
2003-03-27 5:26 ` Rusty Russell [this message]
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