x86: move vgetcpu mode probing to cpu detection

Take it out of time initialization and move it to
cpu detection time.

Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 088fbdb..f1af718 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -719,12 +719,24 @@
 #endif
 }
 
+#ifdef CONFIG_X86_64
+static void vgetcpu_set_mode(void)
+{
+	if (cpu_has(&boot_cpu_data, X86_FEATURE_RDTSCP))
+		vgetcpu_mode = VGETCPU_RDTSCP;
+	else
+		vgetcpu_mode = VGETCPU_LSL;
+}
+#endif
+
 void __init identify_boot_cpu(void)
 {
 	identify_cpu(&boot_cpu_data);
 #ifdef CONFIG_X86_32
 	sysenter_setup();
 	enable_sep_cpu();
+#else
+	vgetcpu_set_mode();
 #endif
 }