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>
diff --git a/arch/x86/oprofile/op_model_amd.c b/arch/x86/oprofile/op_model_amd.c
index a9d1947..ef9d735 100644
--- a/arch/x86/oprofile/op_model_amd.c
+++ b/arch/x86/oprofile/op_model_amd.c
@@ -194,9 +194,18 @@
/* clear all counters */
for (i = 0; i < NUM_CONTROLS; ++i) {
- if (unlikely(!msrs->controls[i].addr))
+ if (unlikely(!msrs->controls[i].addr)) {
+ if (counter_config[i].enabled && !smp_processor_id())
+ /*
+ * counter is reserved, this is on all
+ * cpus, so report only for cpu #0
+ */
+ op_x86_warn_reserved(i);
continue;
+ }
rdmsrl(msrs->controls[i].addr, val);
+ if (val & ARCH_PERFMON_EVENTSEL0_ENABLE)
+ op_x86_warn_in_use(i);
val &= model->reserved;
wrmsrl(msrs->controls[i].addr, val);
}
diff --git a/arch/x86/oprofile/op_model_ppro.c b/arch/x86/oprofile/op_model_ppro.c
index 8eb0587..c344525 100644
--- a/arch/x86/oprofile/op_model_ppro.c
+++ b/arch/x86/oprofile/op_model_ppro.c
@@ -82,9 +82,18 @@
/* clear all counters */
for (i = 0; i < num_counters; ++i) {
- if (unlikely(!msrs->controls[i].addr))
+ if (unlikely(!msrs->controls[i].addr)) {
+ if (counter_config[i].enabled && !smp_processor_id())
+ /*
+ * counter is reserved, this is on all
+ * cpus, so report only for cpu #0
+ */
+ op_x86_warn_reserved(i);
continue;
+ }
rdmsrl(msrs->controls[i].addr, val);
+ if (val & ARCH_PERFMON_EVENTSEL0_ENABLE)
+ op_x86_warn_in_use(i);
val &= model->reserved;
wrmsrl(msrs->controls[i].addr, val);
}
diff --git a/arch/x86/oprofile/op_x86_model.h b/arch/x86/oprofile/op_x86_model.h
index 7b8e75d..59fa2bd 100644
--- a/arch/x86/oprofile/op_x86_model.h
+++ b/arch/x86/oprofile/op_x86_model.h
@@ -57,6 +57,17 @@
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);
