perf: New helper function for pmu name

Introduce perf_pmu_name() helper function that returns the name of the
pmu. This gives us a generic way to get the name of a pmu regardless of
how an architecture identifies it internally.

Signed-off-by: Matt Fleming <matt@console-pimps.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>

3 files changed, 15 insertions, 0 deletions

diff --git a/arch/sh/kernel/perf_event.c b/arch/sh/kernel/perf_event.c
index 2cb9ad59d4b1..55fe89bbdfe0 100644
--- a/arch/sh/kernel/perf_event.c
+++ b/arch/sh/kernel/perf_event.c
@@ -59,6 +59,15 @@ static inline int sh_pmu_initialized(void)
         return !!sh_pmu;
 }
 
+const char *perf_pmu_name(void)
+{
+        if (!sh_pmu)
+                return NULL;
+
+        return sh_pmu->name;
+}
+EXPORT_SYMBOL_GPL(perf_pmu_name);
+
 int perf_num_counters(void)
 {
         if (!sh_pmu)
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 1a0219247183..33f08dafda2f 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -850,6 +850,7 @@ extern int perf_max_events;
 extern const struct pmu *hw_perf_event_init(struct perf_event *event);
 
 extern int perf_num_counters(void);
+extern const char *perf_pmu_name(void);
 extern void perf_event_task_sched_in(struct task_struct *task);
 extern void perf_event_task_sched_out(struct task_struct *task, struct task_struct *next);
 extern void perf_event_task_tick(struct task_struct *task);
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 403d1804b198..e2534691db0d 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -85,6 +85,11 @@ void __weak hw_perf_enable(void)		{ barrier(); }
 
 void __weak perf_event_print_debug(void)        { }
 
+extern __weak const char *perf_pmu_name(void)
+{
+        return "pmu";
+}
+
 static DEFINE_PER_CPU(int, perf_disable_count);
 
 void perf_disable(void)