From: Thomas Gleixner <tglx@linutronix.de>
Date: Sat, 19 Apr 2008 19:31:26 +0000 (+0200)
Subject: hrtimer: optimize the softirq time optimization
X-Git-Tag: v2.6.26-rc1~1129^2
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=259aae864ceeb2b34e7bafa1ce18d096a357fab2;p=linux-2.6

hrtimer: optimize the softirq time optimization

The previous optimization did not take the case into account where a
clock provides its own softirq_get_time() function.

Check for the availablitiy of the clock get time function first and
then check if we need to retrieve the time for both clocks via
hrtimer_softirq_gettime() to avoid a double evaluation of time in that
case as well.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 70d4adc746..f78777abe7 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -1254,14 +1254,13 @@ void hrtimer_run_queues(void)
 		if (!base->first)
 			continue;
 
-		if (gettime) {
+		if (base->get_softirq_time)
+			base->softirq_time = base->get_softirq_time();
+		else if (gettime) {
 			hrtimer_get_softirq_time(cpu_base);
 			gettime = 0;
 		}
 
-		if (base->get_softirq_time)
-			base->softirq_time = base->get_softirq_time();
-
 		spin_lock(&cpu_base->lock);
 
 		while ((node = base->first)) {