Sigh. /me wanted to be too clever and needs to order more brown
paperbags now.

The rework of the jiffy update code introduced a one off error, which
led to a one off accounting error for last_jiffy_update. This made
jiffies lag behind.

Noticed by Karsten Wiese (cpufreq_ondemand weirdness).

Signed-off-by: Thomas Gleixner <[EMAIL PROTECTED]>

Index: linux-2.6.20-rc6-mm/kernel/time/tick-sched.c
===================================================================
--- linux-2.6.20-rc6-mm.orig/kernel/time/tick-sched.c
+++ linux-2.6.20-rc6-mm/kernel/time/tick-sched.c
@@ -43,7 +43,7 @@ struct tick_sched *tick_get_tick_sched(i
  */
 static void tick_do_update_jiffies64(ktime_t now)
 {
-       unsigned long ticks = 1;
+       unsigned long ticks = 0;
        ktime_t delta;
 
        /* Reevalute with xtime_lock held */
@@ -60,12 +60,12 @@ static void tick_do_update_jiffies64(kti
                if (unlikely(delta.tv64 >= tick_period.tv64)) {
                        s64 incr = ktime_to_ns(tick_period);
 
-                       ticks += ktime_divns(delta, incr);
+                       ticks = ktime_divns(delta, incr);
 
                        last_jiffies_update = ktime_add_ns(last_jiffies_update,
                                                           incr * ticks);
                }
-               do_timer(ticks);
+               do_timer(++ticks);
        }
        write_sequnlock(&xtime_lock);
 }


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