oprofile/x86: warn user if a counter is already active

This patch generates a warning if a counter is already active.

Implemented for AMD and P6 models. P4 is not supported.

Cc: Naga Chumbalkar <nagananda.chumbalkar@hp.com>
Cc: Shashi Belur <shashi-kiran.belur@hp.com>
Cc: Tony Jones <tonyj@suse.de>
Signed-off-by: Robert Richter <robert.richter@amd.com>

arch/x86/oprofile/op_x86_model.h

@@ -57,6 +57,17 @@ struct op_x86_model_spec {
 
 struct op_counter_config;
 
+static inline void op_x86_warn_in_use(int counter)
+{
+	pr_warning("oprofile: counter #%d on cpu #%d may already be used\n",
+		   counter, smp_processor_id());
+}
+
+static inline void op_x86_warn_reserved(int counter)
+{
+	pr_warning("oprofile: counter #%d is already reserved\n", counter);
+}
+
 extern u64 op_x86_get_ctrl(struct op_x86_model_spec const *model,
 			   struct op_counter_config *counter_config);
 extern int op_x86_phys_to_virt(int phys);