From: Ingo Molnar <mingo@elte.hu>
Date: Sat, 8 Nov 2008 16:05:38 +0000 (+0100)
Subject: sched: optimize sched_clock() a bit
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=7cbaef9c;p=deliverable%2Flinux.git

sched: optimize sched_clock() a bit

sched_clock() uses cycles_2_ns() needlessly - which is an irq-disabling
variant of __cycles_2_ns().

Most of the time sched_clock() is called with irqs disabled already.
The few places that call it with irqs enabled need to be updated.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---

diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 2ef80e301925..424093b157d3 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -55,7 +55,7 @@ u64 native_sched_clock(void)
 	rdtscll(this_offset);
 
 	/* return the value in ns */
-	return cycles_2_ns(this_offset);
+	return __cycles_2_ns(this_offset);
 }
 
 /* We need to define a real function for sched_clock, to override the