[PATCH 2/7] perf: New helper function for pmu name

[matt@console-pimps.org (Matt Fleming)]

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>
---
 arch/sh/kernel/perf_event.c |    9 +++++++++
 include/linux/perf_event.h  |    1 +
 kernel/perf_event.c         |    5 +++++
 3 files changed, 15 insertions(+), 0 deletions(-)

diff --git a/arch/sh/kernel/perf_event.c b/arch/sh/kernel/perf_event.c
index 2cb9ad5..55fe89b 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 1a02192..33f08da 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 db5b560..fc51268 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)
-- 
1.7.1