[PATCH 31/38] net/decnet: Use time_before, time_before_eq, etc.

[PATCH 31/38] net/decnet: Use time_before, time_before_eq, etc.

[Julia Lawall]

From: Julia Lawall <julia@diku.dk>

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 <julia@diku.dk>
---

diff -r -u -p a/net/decnet/af_decnet.c b/net/decnet/af_decnet.c
--- a/net/decnet/af_decnet.c	2007-11-08 08:00:53.000000000 +0100
+++ b/net/decnet/af_decnet.c	2007-12-23 20:30:40.000000000 +0100
@@ -128,6 +128,7 @@ Version 0.0.6    2.1.110   07-aug-98   E
 #include <linux/stat.h>
 #include <linux/init.h>
 #include <linux/poll.h>
+#include <linux/jiffies.h>
 #include <net/net_namespace.h>
 #include <net/neighbour.h>
 #include <net/dst.h>
@@ -601,7 +602,7 @@ int dn_destroy_timer(struct sock *sk)
 	if (sk->sk_socket)
 		return 0;
 
-	if ((jiffies - scp->stamp) >= (HZ * decnet_time_wait)) {
+	if (time_before_eq(jiffies, scp->stamp + HZ * decnet_time_wait)) {
 		dn_unhash_sock(sk);
 		sock_put(sk);
 		return 1;
diff -r -u -p a/net/decnet/dn_dev.c b/net/decnet/dn_dev.c
--- a/net/decnet/dn_dev.c	2007-12-04 13:19:55.000000000 +0100
+++ b/net/decnet/dn_dev.c	2007-12-23 20:30:40.000000000 +0100
@@ -40,6 +40,7 @@
 #include <linux/skbuff.h>
 #include <linux/sysctl.h>
 #include <linux/notifier.h>
+#include <linux/jiffies.h>
 #include <asm/uaccess.h>
 #include <asm/system.h>
 #include <net/net_namespace.h>
@@ -926,7 +927,7 @@ static void dn_send_endnode_hello(struct
 static int dn_am_i_a_router(struct dn_neigh *dn, struct dn_dev *dn_db, struct dn_ifaddr *ifa)
 {
 	/* First check time since device went up */
-	if ((jiffies - dn_db->uptime) < DRDELAY)
+	if (time_before(jiffies, dn_db->uptime + DRDELAY))
 		return 0;
 
 	/* If there is no router, then yes... */
diff -r -u -p a/net/decnet/dn_nsp_out.c b/net/decnet/dn_nsp_out.c
--- a/net/decnet/dn_nsp_out.c	2007-06-02 22:32:45.000000000 +0200
+++ b/net/decnet/dn_nsp_out.c	2007-12-23 20:30:40.000000000 +0100
@@ -61,6 +61,7 @@
 #include <linux/init.h>
 #include <linux/poll.h>
 #include <linux/if_packet.h>
+#include <linux/jiffies.h>
 #include <net/neighbour.h>
 #include <net/dst.h>
 #include <net/flow.h>
@@ -364,7 +365,7 @@ void dn_nsp_queue_xmit(struct sock *sk, 
 	 * Slow start: If we have been idle for more than
 	 * one RTT, then reset window to min size.
 	 */
-	if ((jiffies - scp->stamp) > t)
+	if (time_after(jiffies, scp->stamp + t))
 		scp->snd_window = NSP_MIN_WINDOW;
 
 	if (oth)
diff -r -u -p a/net/decnet/dn_route.c b/net/decnet/dn_route.c
--- a/net/decnet/dn_route.c	2007-11-13 16:01:33.000000000 +0100
+++ b/net/decnet/dn_route.c	2007-12-23 20:30:40.000000000 +0100
@@ -76,6 +76,7 @@
 #include <linux/netfilter_decnet.h>
 #include <linux/rcupdate.h>
 #include <linux/times.h>
+#include <linux/jiffies.h>
 #include <asm/errno.h>
 #include <net/net_namespace.h>
 #include <net/netlink.h>
@@ -178,7 +179,7 @@ static void dn_dst_check_expire(unsigned
 		}
 		spin_unlock(&dn_rt_hash_table[i].lock);
 
-		if ((jiffies - now) > 0)
+		if (time_after(jiffies, now))
 			break;
 	}
 
diff -r -u -p a/net/decnet/dn_timer.c b/net/decnet/dn_timer.c
--- a/net/decnet/dn_timer.c	2006-11-30 19:05:46.000000000 +0100
+++ b/net/decnet/dn_timer.c	2007-12-23 20:30:40.000000000 +0100
@@ -21,6 +21,7 @@
 #include <linux/netdevice.h>
 #include <linux/timer.h>
 #include <linux/spinlock.h>
+#include <linux/jiffies.h>
 #include <net/sock.h>
 #include <asm/atomic.h>
 #include <net/flow.h>
@@ -96,7 +97,7 @@ static void dn_slow_timer(unsigned long 
 	 * since the last successful transmission.
 	 */
 	if (scp->keepalive && scp->keepalive_fxn && (scp->state == DN_RUN)) {
-		if ((jiffies - scp->stamp) >= scp->keepalive)
+		if (time_before_eq(jiffies, scp->stamp + scp->keepalive))
 			scp->keepalive_fxn(sk);
 	}
 

Re: [PATCH 31/38] net/decnet: Use time_before, time_before_eq, etc.

[YOSHIFUJI Hideaki / 吉藤英明]

In article <Pine.LNX.4.64.0712241547080.23999@ask.diku.dk> (at Mon, 24 Dec 2007 15:47:32 +0100 (CET)), Julia Lawall <julia@diku.dk> says:

> From: Julia Lawall <julia@diku.dk>
> 
> The functions time_before, time_before_eq, time_after, and time_after_eq
> are more robust for comparing jiffies against other values.


> - jiffies >= E
> + time_after_eq(jiffies,E)


> diff -r -u -p a/net/decnet/af_decnet.c b/net/decnet/af_decnet.c
> --- a/net/decnet/af_decnet.c	2007-11-08 08:00:53.000000000 +0100
> +++ b/net/decnet/af_decnet.c	2007-12-23 20:30:40.000000000 +0100
:
> @@ -601,7 +602,7 @@ int dn_destroy_timer(struct sock *sk)
>  	if (sk->sk_socket)
>  		return 0;
>  
> -	if ((jiffies - scp->stamp) >= (HZ * decnet_time_wait)) {
> +	if (time_before_eq(jiffies, scp->stamp + HZ * decnet_time_wait)) {
>  		dn_unhash_sock(sk);
>  		sock_put(sk);
>  		return 1;

ugh?

> --- a/net/decnet/dn_timer.c	2006-11-30 19:05:46.000000000 +0100
> +++ b/net/decnet/dn_timer.c	2007-12-23 20:30:40.000000000 +0100
> @@ -21,6 +21,7 @@
>  #include <linux/netdevice.h>
>  #include <linux/timer.h>
>  #include <linux/spinlock.h>
> +#include <linux/jiffies.h>
>  #include <net/sock.h>
>  #include <asm/atomic.h>
>  #include <net/flow.h>
> @@ -96,7 +97,7 @@ static void dn_slow_timer(unsigned long 
>  	 * since the last successful transmission.
>  	 */
>  	if (scp->keepalive && scp->keepalive_fxn && (scp->state == DN_RUN)) {
> -		if ((jiffies - scp->stamp) >= scp->keepalive)
> +		if (time_before_eq(jiffies, scp->stamp + scp->keepalive))
>  			scp->keepalive_fxn(sk);
>  	}
>  

ugh?

--yoshfuji