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Diffstat (limited to 'arch/x86_64/kernel/tsc.c')
-rw-r--r--arch/x86_64/kernel/tsc.c17
1 files changed, 10 insertions, 7 deletions
diff --git a/arch/x86_64/kernel/tsc.c b/arch/x86_64/kernel/tsc.c
index 1a0edbbffaa..48f9a8e6aa9 100644
--- a/arch/x86_64/kernel/tsc.c
+++ b/arch/x86_64/kernel/tsc.c
@@ -13,6 +13,8 @@ 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);
static unsigned int cyc2ns_scale __read_mostly;
@@ -77,7 +79,7 @@ static void handle_cpufreq_delayed_get(struct work_struct *v)
static unsigned int ref_freq = 0;
static unsigned long loops_per_jiffy_ref = 0;
-static unsigned long cpu_khz_ref = 0;
+static unsigned long tsc_khz_ref = 0;
static int time_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
void *data)
@@ -99,7 +101,7 @@ static int time_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
if (!ref_freq) {
ref_freq = freq->old;
loops_per_jiffy_ref = *lpj;
- cpu_khz_ref = cpu_khz;
+ tsc_khz_ref = tsc_khz;
}
if ((val == CPUFREQ_PRECHANGE && freq->old < freq->new) ||
(val == CPUFREQ_POSTCHANGE && freq->old > freq->new) ||
@@ -107,12 +109,12 @@ static int time_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
*lpj =
cpufreq_scale(loops_per_jiffy_ref, ref_freq, freq->new);
- cpu_khz = cpufreq_scale(cpu_khz_ref, ref_freq, freq->new);
+ tsc_khz = cpufreq_scale(tsc_khz_ref, ref_freq, freq->new);
if (!(freq->flags & CPUFREQ_CONST_LOOPS))
- mark_tsc_unstable();
+ mark_tsc_unstable("cpufreq changes");
}
- set_cyc2ns_scale(cpu_khz_ref);
+ set_cyc2ns_scale(tsc_khz_ref);
return 0;
}
@@ -197,10 +199,11 @@ static struct clocksource clocksource_tsc = {
.vread = vread_tsc,
};
-void mark_tsc_unstable(void)
+void mark_tsc_unstable(char *reason)
{
if (!tsc_unstable) {
tsc_unstable = 1;
+ printk("Marking TSC unstable due to %s\n", reason);
/* Change only the rating, when not registered */
if (clocksource_tsc.mult)
clocksource_change_rating(&clocksource_tsc, 0);
@@ -213,7 +216,7 @@ EXPORT_SYMBOL_GPL(mark_tsc_unstable);
void __init init_tsc_clocksource(void)
{
if (!notsc) {
- clocksource_tsc.mult = clocksource_khz2mult(cpu_khz,
+ clocksource_tsc.mult = clocksource_khz2mult(tsc_khz,
clocksource_tsc.shift);
if (check_tsc_unstable())
clocksource_tsc.rating = 0;