x86: merge sched_clock handling

Move the basic global variable definitions and sched_clock handling in the
common "tsc.c" file.

 - Unify notsc kernel command line handling for 32 bit and 64bit.
 - Functional changes for 64bit.
        - "tsc_disabled" is updated if "notsc" is passed at boottime.
        - Fallback to jiffies for sched_clock, incase notsc is passed on
	  commandline.

Signed-off-by: Alok N Kataria <akataria@vmware.com>
Signed-off-by: Dan Hecht <dhecht@vmware.com>
Cc: Dan Hecht <dhecht@vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 11 insertions, 56 deletions

diff --git a/arch/x86/kernel/tsc_64.c b/arch/x86/kernel/tsc_64.c
index 9898fb01edfd..69cbe4c9f050 100644
--- a/arch/x86/kernel/tsc_64.c
+++ b/arch/x86/kernel/tsc_64.c
@@ -13,12 +13,8 @@
 #include <asm/timer.h>
 #include <asm/vgtod.h>
 
-static int notsc __initdata = 0;
-
-unsigned int cpu_khz;           /* TSC clocks / usec, not used here */
-EXPORT_SYMBOL(cpu_khz);
-unsigned int tsc_khz;
-EXPORT_SYMBOL(tsc_khz);
+extern int tsc_unstable;
+extern int tsc_disabled;
 
 /* Accelerators for sched_clock()
  * convert from cycles(64bits) => nanoseconds (64bits)
@@ -41,6 +37,7 @@ EXPORT_SYMBOL(tsc_khz);
  *
  *                      -johnstul@us.ibm.com "math is hard, lets go shopping!"
  */
+
 DEFINE_PER_CPU(unsigned long, cyc2ns);
 
 static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu)
@@ -63,41 +60,6 @@ static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu)
         local_irq_restore(flags);
 }
 
-unsigned long long native_sched_clock(void)
-{
-        unsigned long a = 0;
-
-        /* Could do CPU core sync here. Opteron can execute rdtsc speculatively,
-         * which means it is not completely exact and may not be monotonous
-         * between CPUs. But the errors should be too small to matter for
-         * scheduling purposes.
-         */
-
-        rdtscll(a);
-        return cycles_2_ns(a);
-}
-
-/* We need to define a real function for sched_clock, to override the
-   weak default version */
-#ifdef CONFIG_PARAVIRT
-unsigned long long sched_clock(void)
-{
-        return paravirt_sched_clock();
-}
-#else
-unsigned long long
-sched_clock(void) __attribute__((alias("native_sched_clock")));
-#endif
-
-
-static int tsc_unstable;
-
-int check_tsc_unstable(void)
-{
-        return tsc_unstable;
-}
-EXPORT_SYMBOL_GPL(check_tsc_unstable);
-
 #ifdef CONFIG_CPU_FREQ
 
 /* Frequency scaling support. Adjust the TSC based timer when the cpu frequency
@@ -281,14 +243,6 @@ __cpuinit int unsynchronized_tsc(void)
         return num_present_cpus() > 1;
 }
 
-int __init notsc_setup(char *s)
-{
-        notsc = 1;
-        return 1;
-}
-
-__setup("notsc", notsc_setup);
-
 static struct clocksource clocksource_tsc;
 
 /*
@@ -346,12 +300,13 @@ EXPORT_SYMBOL_GPL(mark_tsc_unstable);
 
 void __init init_tsc_clocksource(void)
 {
-        if (!notsc) {
-                clocksource_tsc.mult = clocksource_khz2mult(tsc_khz,
-                                                        clocksource_tsc.shift);
-                if (check_tsc_unstable())
-                        clocksource_tsc.rating = 0;
+        if (tsc_disabled > 0)
+                return;
 
-                clocksource_register(&clocksource_tsc);
-        }
+        clocksource_tsc.mult = clocksource_khz2mult(tsc_khz,
+                        clocksource_tsc.shift);
+        if (check_tsc_unstable())
+                clocksource_tsc.rating = 0;
+
+        clocksource_register(&clocksource_tsc);
 }