x86/oprofile: Enable multiplexing only if the model supports it

This patch checks if the model supports multiplexing. Only then
multiplexing will be enabled. The code is added to the common x86
initialization.
Signed-off-by: Robert Richter <robert.richter@amd.com>

arch/x86/oprofile/nmi_int.c

@@ -258,6 +258,12 @@ static int nmi_switch_event(void)
 	return 0;
 }
 
+static inline void mux_init(struct oprofile_operations *ops)
+{
+	if (has_mux())
+		ops->switch_events = nmi_switch_event;
+}
+
 #else
 
 inline int op_x86_phys_to_virt(int phys) { return phys; }
@@ -265,6 +271,7 @@ static inline void nmi_shutdown_mux(void) { }
 static inline int nmi_setup_mux(void) { return 1; }
 static inline void
 nmi_cpu_setup_mux(int cpu, struct op_msrs const * const msrs) { }
+static inline void mux_init(struct oprofile_operations *ops) { }
 
 #endif
 
@@ -682,9 +689,6 @@ int __init op_nmi_init(struct oprofile_operations *ops)
 	ops->start		= nmi_start;
 	ops->stop		= nmi_stop;
 	ops->cpu_type		= cpu_type;
-#ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
-	ops->switch_events	= nmi_switch_event;
-#endif
 
 	if (model->init)
 		ret = model->init(ops);
@@ -694,6 +698,8 @@ int __init op_nmi_init(struct oprofile_operations *ops)
 	if (!model->num_virt_counters)
 		model->num_virt_counters = model->num_counters;
 
+	mux_init(ops);
+
 	init_sysfs();
 	using_nmi = 1;
 	printk(KERN_INFO "oprofile: using NMI interrupt.\n");