linux-kernel - [PATCH V2 12/36] hrtimer: use base->hres_active directly instead of hrtimer_hres

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Date:	Fri,  4 Apr 2014 12:05:55 +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 12/36] hrtimer: use base->hres_active directly instead of hrtimer_hres_active()

retrigger_next_event() is defined within #ifdef CONFIG_HIGH_RES_TIMERS as we
already have pointer to base available. So it makes more sense to simple use
base->hres_active instead of doing this by calling hrtimer_hres_active():

	__this_cpu_read(hrtimer_bases.hres_active)

Also the same reason apply to code in __remove_hrtimer().

There is one more noticeable issue with __remove_hrtimer() without this patch.
We are checking hres_active of *this cpu's* base, where as it is not guanrateed
at all that __remove_hrtimer() would be called on this CPU. Specially from the
migration code, timer's CPU is already down.

Signed-off-by: Viresh Kumar <viresh.kumar@...aro.org>
---
 kernel/hrtimer.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index b0fbf12..ad5b7ba 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -672,7 +672,7 @@ static void retrigger_next_event(void *arg)
 {
 	struct hrtimer_cpu_base *base = &__get_cpu_var(hrtimer_bases);
 
-	if (!hrtimer_hres_active())
+	if (!base->hres_active)
 		return;
 
 	raw_spin_lock(&base->lock);
@@ -897,7 +897,7 @@ static void __remove_hrtimer(struct hrtimer *timer,
 	if (&timer->node == next_timer) {
 #ifdef CONFIG_HIGH_RES_TIMERS
 		/* Reprogram the clock event device. if enabled */
-		if (reprogram && hrtimer_hres_active()) {
+		if (reprogram && base->cpu_base->hres_active) {
 			ktime_t expires;
 
 			expires = ktime_sub(hrtimer_get_expires(timer),
-- 
1.7.12.rc2.18.g61b472e

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