Re: [PATCH] Dynamic Tick version 050406-1

[Tony Lindgren]

* Frank Sorenson <frank@xxxxxxxxxxxx> [050406 14:16]:
> Tony Lindgren wrote:
> > Hi all,
> > 
> > Here's an updated dyn-tick patch. Some minor fixes:
> 
> Doesn't look so good here.  I get this with 2.6.12-rc2 (plus a few other patches).
> Disabling Dynamic Tick makes everything happy again (it boots).
> 
> [4294688.655000] Unable to handle kernel NULL pointer dereference at virtual address 00000000

Thanks for trying it out. What kind of hardware do you have? Does it
have HPET? It looks like no suitable timer for dyn-tick is found...
Maybe the following patch helps?

Tony
--- a/kernel/dyn-tick-timer.c	2005-03-01 16:41:05 -08:00
+++ b/kernel/dyn-tick-timer.c	2005-04-07 00:57:30 -07:00
@@ -232,10 +232,6 @@
 {
 	int ret = 0;
 
-	ret = sysdev_create_file(&device_timer, &attr_dyn_tick_state);
-	ret = sysdev_create_file(&device_timer, &attr_dyn_tick_int);
-	ret = sysdev_create_file(&device_timer, &attr_dyn_tick_dbg);
-
 	if (dyn_tick_cfg->arch_init == NULL ||
 	    !(dyn_tick->state & DYN_TICK_SUITABLE))
 		return -ENODEV;
@@ -245,6 +241,10 @@
 		printk(KERN_WARNING "dyn-tick: Init failed\n");
 		return -ENODEV;
 	}
+
+	ret = sysdev_create_file(&device_timer, &attr_dyn_tick_state);
+	ret = sysdev_create_file(&device_timer, &attr_dyn_tick_int);
+	ret = sysdev_create_file(&device_timer, &attr_dyn_tick_dbg);
 
 	printk(KERN_INFO "dyn-tick: Timer using dynamic tick\n");