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authorMichal Simek <monstr@monstr.eu>2012-03-30 12:10:03 +0200
committerMichal Simek <monstr@monstr.eu>2012-03-30 12:10:03 +0200
commit6a4770e335bd4df0a4577146f76e116ab6e23f40 (patch)
tree305056c20b6ccf3a4fed00e9e32f3a1dd039cd70 /arch/x86/kernel/tsc.c
parentac64a9caa55bdfd8d24784f25c68cb7919ddabe3 (diff)
parentf52b69f86e27903d6896ed5fa7cd280fec8de532 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into next
Diffstat (limited to 'arch/x86/kernel/tsc.c')
-rw-r--r--arch/x86/kernel/tsc.c17
1 files changed, 14 insertions, 3 deletions
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index a62c201c97ec..fc0a147e3727 100644
--- 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;
}