2007-12-24 14:45:48

by Julia Lawall

Subject: [PATCH 30/38] net/bridge: Use time_before, time_before_eq, etc.

From: Julia Lawall <[email protected]>

The functions time_before, time_before_eq, time_after, and time_after_eq
are more robust for comparing jiffies against other values.

A simplified version of the semantic patch making this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@ change_compare_np @
expression E;
@@

(
- jiffies <= E
+ time_before_eq(jiffies,E)
|
- jiffies >= E
+ time_after_eq(jiffies,E)
|
- jiffies < E
+ time_before(jiffies,E)
|
- jiffies > E
+ time_after(jiffies,E)
)

@ include depends on change_compare_np @
@@

#include <linux/jiffies.h>

@ no_include depends on !include && change_compare_np @
@@

#include <linux/...>
+ #include <linux/jiffies.h>
// </smpl>

Signed-off-by: Julia Lawall <[email protected]>
---

diff -r -u -p a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c
--- a/net/bridge/br_netfilter.c 2007-11-15 15:09:37.000000000 +0100
+++ b/net/bridge/br_netfilter.c 2007-12-23 20:30:40.000000000 +0100
@@ -46,6 +46,7 @@
#include "br_private.h"
#ifdef CONFIG_SYSCTL
#include <linux/sysctl.h>
+#include <linux/jiffies.h>
#endif

#define skb_origaddr(skb) (((struct bridge_skb_cb *) \
@@ -221,7 +222,7 @@ static void __br_dnat_complain(void)
{
static unsigned long last_complaint;

- if (jiffies - last_complaint >= 5 * HZ) {
+ if (time_before_eq(jiffies, last_complaint + 5 * HZ)) {
printk(KERN_WARNING "Performing cross-bridge DNAT requires IP "
"forwarding to be enabled\n");
last_complaint = jiffies;

2007-12-24 17:25:13

by Stephen Hemminger

Subject: Re: [PATCH 30/38] net/bridge: Use time_before, time_before_eq, etc.

On Mon, 24 Dec 2007 15:45:32 +0100 (CET)
Julia Lawall <[email protected]> wrote:

> From: Julia Lawall <[email protected]>
>
> The functions time_before, time_before_eq, time_after, and time_after_eq
> are more robust for comparing jiffies against other values.
>
> A simplified version of the semantic patch making this change is as follows:
> (http://www.emn.fr/x-info/coccinelle/)
>
> // <smpl>
> @ change_compare_np @
> expression E;
> @@
>
> (
> - jiffies <= E
> + time_before_eq(jiffies,E)
> |
> - jiffies >= E
> + time_after_eq(jiffies,E)
> |
> - jiffies < E
> + time_before(jiffies,E)
> |
> - jiffies > E
> + time_after(jiffies,E)
> )
>
> @ include depends on change_compare_np @
> @@
>
> #include <linux/jiffies.h>
>
> @ no_include depends on !include && change_compare_np @
> @@
>
> #include <linux/...>
> + #include <linux/jiffies.h>
> // </smpl>
>
> Signed-off-by: Julia Lawall <[email protected]>
> ---
>
> diff -r -u -p a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c
> --- a/net/bridge/br_netfilter.c 2007-11-15 15:09:37.000000000 +0100
> +++ b/net/bridge/br_netfilter.c 2007-12-23 20:30:40.000000000 +0100
> @@ -46,6 +46,7 @@
> #include "br_private.h"
> #ifdef CONFIG_SYSCTL
> #include <linux/sysctl.h>
> +#include <linux/jiffies.h>
> #endif
>
> #define skb_origaddr(skb) (((struct bridge_skb_cb *) \
> @@ -221,7 +222,7 @@ static void __br_dnat_complain(void)
> {
> static unsigned long last_complaint;
>
> - if (jiffies - last_complaint >= 5 * HZ) {
> + if (time_before_eq(jiffies, last_complaint + 5 * HZ)) {
> printk(KERN_WARNING "Performing cross-bridge DNAT requires IP "
> "forwarding to be enabled\n");
> last_complaint = jiffies;

I would recommend changing this to net_ratelimit() instead.


--
Stephen Hemminger <[email protected]>