linux-kernel - [PATCH V2 25/36] hrtimer: call hrtimer_get_softirq_time() only if cpu_base->active

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Date:	Fri,  4 Apr 2014 12:06:08 +0530
From:	Viresh Kumar <viresh.kumar@...aro.org>
To:	tglx@...utronix.de
Cc:	linaro-kernel@...ts.linaro.org, fweisbec@...il.com,
	linaro-networking@...aro.org, Arvind.Chauhan@....com,
	linux-kernel@...r.kernel.org,
	Viresh Kumar <viresh.kumar@...aro.org>
Subject: [PATCH V2 25/36] hrtimer: call hrtimer_get_softirq_time() only if cpu_base->active_bases is set

We need to call hrtimer_get_softirq_time() only once for a cpu_base from
hrtimer_run_queues(). And it shouldn't be called if there are no timers queued
for that cpu_base.

Currently we are managing this with help of a variable: gettime. This part of
code can be simplified by using cpu_base->active_bases instead. With this we can
get rid of the 'if' block from the loop iterating over all clock bases.

Signed-off-by: Viresh Kumar <viresh.kumar@...aro.org>
---
 kernel/hrtimer.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index b3ab19a..2d9a7e2 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -1458,19 +1458,16 @@ void hrtimer_run_queues(void)
 	struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases);
 	struct hrtimer_clock_base *base;
 	unsigned int active_bases;
-	int index, gettime = 1;
+	int index;
 
 	if (hrtimer_hres_active())
 		return;
 
-	for_each_active_base(index, base, cpu_base, active_bases) {
-		if (gettime) {
-			hrtimer_get_softirq_time(cpu_base);
-			gettime = 0;
-		}
+	if (cpu_base->active_bases)
+		hrtimer_get_softirq_time(cpu_base);
 
+	for_each_active_base(index, base, cpu_base, active_bases) {
 		raw_spin_lock(&cpu_base->lock);
-
 		while ((node = timerqueue_getnext(&base->active))) {
 			struct hrtimer *timer;
 
-- 
1.7.12.rc2.18.g61b472e

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