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-rw-r--r--arch/x86/include/asm/tsc.h2
-rw-r--r--arch/x86/kernel/tsc.c2
-rw-r--r--arch/x86/kernel/tsc_sync.c4
3 files changed, 5 insertions, 3 deletions
diff --git a/arch/x86/include/asm/tsc.h b/arch/x86/include/asm/tsc.h
index 83e2efd181e2..15d99153a96d 100644
--- a/arch/x86/include/asm/tsc.h
+++ b/arch/x86/include/asm/tsc.h
@@ -51,6 +51,8 @@ extern int unsynchronized_tsc(void);
51extern int check_tsc_unstable(void); 51extern int check_tsc_unstable(void);
52extern unsigned long native_calibrate_tsc(void); 52extern unsigned long native_calibrate_tsc(void);
53 53
54extern int tsc_clocksource_reliable;
55
54/* 56/*
55 * Boot-time check whether the TSCs are synchronized across 57 * Boot-time check whether the TSCs are synchronized across
56 * all CPUs/cores: 58 * all CPUs/cores:
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index db483369f10b..eee465109e16 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -35,7 +35,7 @@ static int __read_mostly tsc_unstable;
35 erroneous rdtsc usage on !cpu_has_tsc processors */ 35 erroneous rdtsc usage on !cpu_has_tsc processors */
36static int __read_mostly tsc_disabled = -1; 36static int __read_mostly tsc_disabled = -1;
37 37
38static int tsc_clocksource_reliable; 38int tsc_clocksource_reliable;
39/* 39/*
40 * Scheduler clock - returns current time in nanosec units. 40 * Scheduler clock - returns current time in nanosec units.
41 */ 41 */
diff --git a/arch/x86/kernel/tsc_sync.c b/arch/x86/kernel/tsc_sync.c
index 0aa5fed8b9e6..9eba29b46cb7 100644
--- a/arch/x86/kernel/tsc_sync.c
+++ b/arch/x86/kernel/tsc_sync.c
@@ -113,7 +113,7 @@ void __cpuinit check_tsc_sync_source(int cpu)
113 if (unsynchronized_tsc()) 113 if (unsynchronized_tsc())
114 return; 114 return;
115 115
116 if (boot_cpu_has(X86_FEATURE_TSC_RELIABLE)) { 116 if (tsc_clocksource_reliable) {
117 if (cpu == (nr_cpu_ids-1) || system_state != SYSTEM_BOOTING) 117 if (cpu == (nr_cpu_ids-1) || system_state != SYSTEM_BOOTING)
118 pr_info( 118 pr_info(
119 "Skipped synchronization checks as TSC is reliable.\n"); 119 "Skipped synchronization checks as TSC is reliable.\n");
@@ -172,7 +172,7 @@ void __cpuinit check_tsc_sync_target(void)
172{ 172{
173 int cpus = 2; 173 int cpus = 2;
174 174
175 if (unsynchronized_tsc() || boot_cpu_has(X86_FEATURE_TSC_RELIABLE)) 175 if (unsynchronized_tsc() || tsc_clocksource_reliable)
176 return; 176 return;
177 177
178 /* 178 /*