drivers/char/rtc.c: use time_before, time_before_eq, etc
authorJulia Lawall <julia@diku.dk>
Mon, 28 Apr 2008 09:11:59 +0000 (02:11 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Mon, 28 Apr 2008 15:58:17 +0000 (08:58 -0700)
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>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/char/rtc.c

index 5c3142b..e2ec2ee 100644 (file)
@@ -88,6 +88,7 @@
 
 #ifdef CONFIG_SPARC32
 #include <linux/pci.h>
+#include <linux/jiffies.h>
 #include <asm/ebus.h>
 
 static unsigned long rtc_port;
@@ -1316,7 +1317,8 @@ void rtc_get_rtc_time(struct rtc_time *rtc_tm)
         * Once the read clears, read the RTC time (again via ioctl). Easy.
         */
 
-       while (rtc_is_updating() != 0 && jiffies - uip_watchdog < 2*HZ/100)
+       while (rtc_is_updating() != 0 &&
+              time_before(jiffies, uip_watchdog + 2*HZ/100))
                cpu_relax();
 
        /*