linux-kernel - [tip:sched/core] sched/clock: Remove pointless test in cpu_clock/local

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Date:	Wed, 13 Apr 2016 04:48:25 -0700
From:	tip-bot for Daniel Lezcano <tipbot@...or.com>
To:	linux-tip-commits@...r.kernel.org
Cc:	torvalds@...ux-foundation.org, mingo@...nel.org,
	tglx@...utronix.de, linux-kernel@...r.kernel.org,
	daniel.lezcano@...aro.org, hpa@...or.com, peterz@...radead.org
Subject: [tip:sched/core] sched/clock: Remove pointless test in
 cpu_clock/local_clock

Commit-ID:  c78b17e28cc2c2df74264afc408bdc6aaf3fbcc8
Gitweb:     http://git.kernel.org/tip/c78b17e28cc2c2df74264afc408bdc6aaf3fbcc8
Author:     Daniel Lezcano <daniel.lezcano@...aro.org>
AuthorDate: Mon, 11 Apr 2016 16:38:33 +0200
Committer:  Ingo Molnar <mingo@...nel.org>
CommitDate: Wed, 13 Apr 2016 12:25:22 +0200

sched/clock: Remove pointless test in cpu_clock/local_clock

In case the HAVE_UNSTABLE_SCHED_CLOCK config is set, the cpu_clock() version
checks if sched_clock_stable() is not set and calls sched_clock_cpu(),
otherwise it calls sched_clock().

sched_clock_cpu() checks also if sched_clock_stable() is set and, if true,
calls sched_clock().

sched_clock() will be called in sched_clock_cpu() if sched_clock_stable() is
true.

Remove the duplicate test by directly calling sched_clock_cpu() and let the
static key act in this function instead.

Signed-off-by: Daniel Lezcano <daniel.lezcano@...aro.org>
Cc: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: Peter Zijlstra <peterz@...radead.org>
Cc: Thomas Gleixner <tglx@...utronix.de>
Link: http://lkml.kernel.org/r/1460385514-14700-1-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar <mingo@...nel.org>
---
 kernel/sched/clock.c | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c
index fedb967..30c4b20 100644
--- a/kernel/sched/clock.c
+++ b/kernel/sched/clock.c
@@ -375,10 +375,7 @@ EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event);
  */
 u64 cpu_clock(int cpu)
 {
-	if (!sched_clock_stable())
-		return sched_clock_cpu(cpu);
-
-	return sched_clock();
+	return sched_clock_cpu(cpu);
 }
 
 /*
@@ -390,10 +387,7 @@ u64 cpu_clock(int cpu)
  */
 u64 local_clock(void)
 {
-	if (!sched_clock_stable())
-		return sched_clock_cpu(raw_smp_processor_id());
-
-	return sched_clock();
+	return sched_clock_cpu(raw_smp_processor_id());
 }
 
 #else /* CONFIG_HAVE_UNSTABLE_SCHED_CLOCK */