ARM: 6071/1: perf-events: allow modules to query the number of hardware counters
For OProfile to initialise oprofilefs correctly, it needs to know
the number of counters it can represent.
This patch adds a function to the ARM perf-events backend to return
the number of hardware counters available for the current PMU.
Cc: Jamie Iles <jamie.iles@picochip.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/include/asm/perf_event.h b/arch/arm/include/asm/perf_event.h
index fa4b326..48837e6 100644
--- a/arch/arm/include/asm/perf_event.h
+++ b/arch/arm/include/asm/perf_event.h
@@ -42,4 +42,7 @@
extern enum arm_perf_pmu_ids
armpmu_get_pmu_id(void);
+extern int
+armpmu_get_max_events(void);
+
#endif /* __ARM_PERF_EVENT_H__ */
diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index 381f121..c457686 100644
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -111,6 +111,18 @@
}
EXPORT_SYMBOL_GPL(armpmu_get_pmu_id);
+int
+armpmu_get_max_events(void)
+{
+ int max_events = 0;
+
+ if (armpmu != NULL)
+ max_events = armpmu->num_events;
+
+ return max_events;
+}
+EXPORT_SYMBOL_GPL(armpmu_get_max_events);
+
#define HW_OP_UNSUPPORTED 0xFFFF
#define C(_x) \