linux-kernel - [PATCH] x86: remove unused code in set_cyc2ns

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Date:	Tue, 29 Jan 2008 22:15:01 +0100
From:	Guillaume Chazarain <guichaz@...oo.fr>
To:	Ingo Molnar <mingo@...e.hu>
Cc:	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	"H. Peter Anvin" <hpa@...or.com>,
	Guillaume Chazarain <guichaz@...oo.fr>
Subject: [PATCH] x86: remove unused code in set_cyc2ns_scale()

This should be fold into:
4f95bd6e2b21a8c724357463f8341502d47aba13
x86: scale cyc_2_nsec according to CPU frequency

Signed-off-by: Guillaume Chazarain <guichaz@...oo.fr>
---
 arch/x86/kernel/tsc_32.c |   14 +++++---------
 arch/x86/kernel/tsc_64.c |   14 +++++---------
 2 files changed, 10 insertions(+), 18 deletions(-)

diff --git a/arch/x86/kernel/tsc_32.c b/arch/x86/kernel/tsc_32.c
index 43517e3..e05e221 100644
--- a/arch/x86/kernel/tsc_32.c
+++ b/arch/x86/kernel/tsc_32.c
@@ -83,20 +83,16 @@ DEFINE_PER_CPU(unsigned long, cyc2ns);
 
 static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu)
 {
-	unsigned long flags, prev_scale, *scale;
-	unsigned long long tsc_now, ns_now;
+	unsigned long flags, *scale;
+
+	if (!cpu_khz)
+		return;
 
 	local_irq_save(flags);
 	sched_clock_idle_sleep_event();
 
 	scale = &per_cpu(cyc2ns, cpu);
-
-	rdtscll(tsc_now);
-	ns_now = __cycles_2_ns(tsc_now);
-
-	prev_scale = *scale;
-	if (cpu_khz)
-		*scale = (NSEC_PER_MSEC << CYC2NS_SCALE_FACTOR)/cpu_khz;
+	*scale = (NSEC_PER_MSEC << CYC2NS_SCALE_FACTOR)/cpu_khz;
 
 	/*
 	 * Start smoothly with the new frequency:
diff --git a/arch/x86/kernel/tsc_64.c b/arch/x86/kernel/tsc_64.c
index 947554d..e0e9d4f 100644
--- a/arch/x86/kernel/tsc_64.c
+++ b/arch/x86/kernel/tsc_64.c
@@ -44,20 +44,16 @@ DEFINE_PER_CPU(unsigned long, cyc2ns);
 
 static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu)
 {
-	unsigned long flags, prev_scale, *scale;
-	unsigned long long tsc_now, ns_now;
+	unsigned long flags, *scale;
+
+	if (!cpu_khz)
+		return;
 
 	local_irq_save(flags);
 	sched_clock_idle_sleep_event();
 
 	scale = &per_cpu(cyc2ns, cpu);
-
-	rdtscll(tsc_now);
-	ns_now = __cycles_2_ns(tsc_now);
-
-	prev_scale = *scale;
-	if (cpu_khz)
-		*scale = (NSEC_PER_MSEC << CYC2NS_SCALE_FACTOR)/cpu_khz;
+	*scale = (NSEC_PER_MSEC << CYC2NS_SCALE_FACTOR)/cpu_khz;
 
 	sched_clock_idle_wakeup_event(0);
 	local_irq_restore(flags);
-- 
1.5.3.7

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