perf: provide sysfs_show for struct perf_pmu_events_attr

(struct perf_pmu_events_attr) is defined in include/linux/perf_event.h,
but the only "show" for it is in x86 and contains x86 specific stuff.

Make a generic one for those of us who are just using the event_str.

Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

2 files changed, 15 insertions, 0 deletions

diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 486e84ccb1f9..58f59bdb590b 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -897,6 +897,9 @@ struct perf_pmu_events_attr {
         const char *event_str;
 };
 
+ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr,
+                              char *page);
+
 #define PMU_EVENT_ATTR(_name, _var, _id, _show)                         \
 static struct perf_pmu_events_attr _var = {                             \
         .attr = __ATTR(_name, 0444, _show, NULL),                       \
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 4c1ee7f2bebc..934687f8d51b 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8276,6 +8276,18 @@ void __init perf_event_init(void)
                      != 1024);
 }
 
+ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr,
+                              char *page)
+{
+        struct perf_pmu_events_attr *pmu_attr =
+                container_of(attr, struct perf_pmu_events_attr, attr);
+
+        if (pmu_attr->event_str)
+                return sprintf(page, "%s\n", pmu_attr->event_str);
+
+        return 0;
+}
+
 static int __init perf_event_sysfs_init(void)
 {
         struct pmu *pmu;