x86: round_jiffies() for i386 and x86-64 non-critical/corrected MCE p…

…olling

This helps to reduce the frequency at which the CPU must be taken out of a
lower-power state.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Acked-by: Tim Hockin <thockin@hockin.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/i386/kernel/cpu/mcheck/non-fatal.c

@@ -57,7 +57,7 @@ static DECLARE_DELAYED_WORK(mce_work, mce_work_fn);
 static void mce_work_fn(struct work_struct *work)
 { 
 	on_each_cpu(mce_checkregs, NULL, 1, 1);
-	schedule_delayed_work(&mce_work, MCE_RATE);
+	schedule_delayed_work(&mce_work, round_jiffies_relative(MCE_RATE));
 } 
 
 static int __init init_nonfatal_mce_checker(void)
@@ -82,7 +82,7 @@ static int __init init_nonfatal_mce_checker(void)
 	/*
 	 * Check for non-fatal errors every MCE_RATE s
 	 */
-	schedule_delayed_work(&mce_work, MCE_RATE);
+	schedule_delayed_work(&mce_work, round_jiffies_relative(MCE_RATE));
 	printk(KERN_INFO "Machine check exception polling timer started.\n");
 	return 0;
 }

arch/x86_64/kernel/mce.c

@@ -375,7 +375,8 @@ static void mcheck_timer(struct work_struct *work)
 	if (mce_notify_user()) {
 		next_interval = max(next_interval/2, HZ/100);
 	} else {
-		next_interval = min(next_interval*2, check_interval*HZ);
+		next_interval = min(next_interval*2,
+				(int)round_jiffies_relative(check_interval*HZ));
 	}
 
 	schedule_delayed_work(&mcheck_work, next_interval);
@@ -428,7 +429,8 @@ static __init int periodic_mcheck_init(void)
 { 
 	next_interval = check_interval * HZ;
 	if (next_interval)
-		schedule_delayed_work(&mcheck_work, next_interval);
+		schedule_delayed_work(&mcheck_work,
+				      round_jiffies_relative(next_interval));
 	idle_notifier_register(&mce_idle_notifier);
 	return 0;
 } 
@@ -720,7 +722,8 @@ static void mce_restart(void)
 	on_each_cpu(mce_init, NULL, 1, 1);       
 	next_interval = check_interval * HZ;
 	if (next_interval)
-		schedule_delayed_work(&mcheck_work, next_interval);
+		schedule_delayed_work(&mcheck_work,
+				      round_jiffies_relative(next_interval));
 }
 
 static struct sysdev_class mce_sysclass = {