From: Bhavana Nagendra <bnagendr@redhat.com>
Date: Tue, 12 Feb 2008 12:24:38 -0500
Subject: [cpufreq] xen: properly register notifier
Message-id: 20080212172436.29440.10846.sendpatchset@localhost.localdomain
O-Subject: [RHEL5.2 PATCH] Fix cpufreq notifier error message at boottime
Bugzilla: 430940

Resolves BZ 430940

While booting specific systems the kernel reports an failure "failed to set up
cpufreq notifier" with Xen configurations.  This was seen on RHTS by Red Hat
engineers and was reported as a regression.

The fix is trivial as the logic for printing the error is switched.
cpufreq_register_notifier returns 0 on success and the current code prints
the error mesage when !cpufreq_register_notifier(). Thus the check fails
everytime.

Tested on Barcelona Anaheim system, patch gets ride of the eror message.

Please ACK.

Acked-by: Prarit Bhargava <prarit@redhat.com>

diff --git a/arch/i386/kernel/time-xen.c b/arch/i386/kernel/time-xen.c
index 532ad14..2a6f8e1 100644
--- a/arch/i386/kernel/time-xen.c
+++ b/arch/i386/kernel/time-xen.c
@@ -1118,7 +1118,7 @@ static struct notifier_block time_cpufreq_notifier_block = {
 
 static int __init cpufreq_time_setup(void)
 {
-	if (!cpufreq_register_notifier(&time_cpufreq_notifier_block,
+	if (cpufreq_register_notifier(&time_cpufreq_notifier_block,
 			CPUFREQ_TRANSITION_NOTIFIER)) {
 		printk(KERN_ERR "failed to set up cpufreq notifier\n");
 		return -ENODEV;