Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-fixes

[karo-tx-linux.git] / arch / x86 / kernel / tsc.c

diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index a62c201c97eccf31fa90d05dec5e5cf5102ead74..fc0a147e372726fb019b8873969dc1fca3e43109 100644 (file)
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -620,7 +620,8 @@ static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu)
 
        if (cpu_khz) {
                *scale = (NSEC_PER_MSEC << CYC2NS_SCALE_FACTOR)/cpu_khz;
-               *offset = ns_now - (tsc_now * *scale >> CYC2NS_SCALE_FACTOR);
+               *offset = ns_now - mult_frac(tsc_now, *scale,
+                                            (1UL << CYC2NS_SCALE_FACTOR));
        }
 
        sched_clock_idle_wakeup_event(0);
@@ -629,7 +630,7 @@ static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu)
 
 static unsigned long long cyc2ns_suspend;
 
-void save_sched_clock_state(void)
+void tsc_save_sched_clock_state(void)
 {
        if (!sched_clock_stable)
                return;
@@ -645,7 +646,7 @@ void save_sched_clock_state(void)
  * that sched_clock() continues from the point where it was left off during
  * suspend.
  */
-void restore_sched_clock_state(void)
+void tsc_restore_sched_clock_state(void)
 {
        unsigned long long offset;
        unsigned long flags;
@@ -932,6 +933,16 @@ static int __init init_tsc_clocksource(void)
                clocksource_tsc.rating = 0;
                clocksource_tsc.flags &= ~CLOCK_SOURCE_IS_CONTINUOUS;
        }
+
+       /*
+        * Trust the results of the earlier calibration on systems
+        * exporting a reliable TSC.
+        */
+       if (boot_cpu_has(X86_FEATURE_TSC_RELIABLE)) {
+               clocksource_register_khz(&clocksource_tsc, tsc_khz);
+               return 0;
+       }
+
        schedule_delayed_work(&tsc_irqwork, 0);
        return 0;
 }